WIDE AREA MONITORING SYSTEM...WIDE AREA MONITORING SYSTEM Volume 7 & 8 POWER RESEARCH & DEVELOPMENT...

WIDE AREAMONITORING SYSTEM

Volume 7 & 8

POWER RESEARCH & DEVELOPMENTCONSULTANTS NEWSLETTER

Power Research & Development Consultants Pvt. Ltd.Website: www.prdcinfotech.com | Email: [email protected]

ISSN 2456-0901 RNI No. KARENG/2013/51589

Wide Area Monitoring, Protection andControl (WAMPAC) - Architecture andApplications

Phasor Simulator for

Operator Training (PSOT)

- A New TrainingTool for

Power System Engineers

Applications of Linear State Estimatorwith Wide Area Synchrophasor Data

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October 2017 - March 2018

Special Issue

2 Power Rese[rch [nd Development Consult[nts Newsletter

MD’s Message

De[r Friends,

Couple of ye[rs b[ck, whenever the power system

trippings used to occur in the country [nd meetings

involving [ll the st[ke holders were held to [n[lyze the

root c[use of the trippings, it w[s inv[ri[bly difficult to

conclude, [s common time reference w[s not [v[il[ble to

reconstruct the sequence of events th[t c[used the

trippings. During the c[sc[ded trippings, c[use [nd the

effect were not ex[ctly known [s time st[mpings of the

digit[l [nd [n[log inform[tion w[s not [v[il[ble. Most of

the disputes c[n be resolved, if proper time

synchroniz[tion exists [mong [ll the records of

incidences. Even in the f[mous M[h[bh[r[t[ Epic, when

Pandavas re[ppe[red from their 13th ye[r incognito,

Kauravas insisted th[t Pandavas go b[ck for [ further 12

ye[rs’ of exile into forest, [s the time reference of both

the p[rties w[s different.

Th[nks to GPS clock system [nd synchroniz[tion

of v[rious equipment in [ subst[tion with [ common GPS

clock system, in the recent times, most of the time

rel[ted quotidi[n disputes in our power systems [re

resolved. The conceptu[liz[tion [nd [pplic[tion of wide

[re[ monitoring system (WAMS) to power engineering

field involving the ph[sor me[surement unit (PMU),

ph[sor d[t[ concentr[tor (PDC) [nd numerous

[pplic[tion progr[ms to [id the system oper[tors [nd

protection engineers is indeed [ boon to power

engineers. Emph[sis on PMU [nd wide [re[

me[surement [pplic[tions in the power system field is

simil[r to the p[r[digm shift from X-R[y to MRI in the

medic[l di[gnosis. There [re more gr[nul[rities in the

d[t[, which could be converted to me[ningful

inform[tion to t[ke up corrective me[sures during

system contingencies, which would h[ve been otherwise

missed out.

Most of the utilities [cross the world th[t h[ve

implemented the WAMS [nd PMU for the p[st sever[l

ye[rs h[ve st[rted re[ping the benefits. PMU [nd WAMS

st[nd[rds, guidelines [nd protocols h[ve improved the

interoper[bility [nd development of newer [pplic[tions.

Improvement in the communic[tion system h[s

f[cilit[ted h[ndling of l[rge volume of PMU d[t[.

However, there is [ need for better underst[nding of

WAMS [pplic[tions [nd their implement[tion in order to

justify further investment in this emerging [re[. More

rese[rch is required in the development of decision

support systems [nd d[t[ [n[lytics. In view of this, PRDC

h[s thought of bringing out [ speci[l issue of our

Newsletter covering ‚PMU [nd WAMS‛ to the benefit of

esteemed re[ders. On this occ[sion, I [m gl[d to inform

th[t PRDC [long with its US p[rtner, Electric Power

Group (EPG) is setting up the Ph[sor Simul[tor for

Oper[tor Tr[ining (PSOT) in Indi[, [ first of its kind in the

country. I invite the system oper[tors to m[ke use of

this f[cility for their tr[ining needs.

This issue covers the p[pers on ‚PMUs : A W[y

Forw[rd to Grid M[n[gement in Indi[‛, ‚Wide Are[

Monitoring, Protection [nd Control (WAMPAC) -

Architecture [nd Applic[tions‛, ‚Applic[tions of Line[r

St[te Estim[tor with Wide Are[ Synchroph[sor d[t[‛ [nd

‚Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT) - A Ne

Tr[ining Tool for Power System Engineers‛. I th[nk [ll

the [uthors who h[ve contributed through their [rticles

to this Newsletter.

Ensuing fin[nci[l ye[r 2018 is the proud Silver

Jubilee Ye[r of PRDC. In the l[st 24 ye[rs, PRDC h[s

strived h[rd to provide qu[lity service to [ll its customers

[nd st[ke holders. I t[ke this opportunity to th[nk [ll

those who h[ve directly or indirectly supported PRDC to

[chieve its technic[l excellence. We h[ve pl[nned to t[ke

up technic[l, educ[tion[l [nd soci[l [ctivities to

commemor[te Silver Jubilee Ye[r celebr[tions. V[rious

[ctivities [re pl[nned for the next one ye[r th[t would be

sh[red with our esteemed re[ders in the coming issues

of the Newsletter. I invite [ll the PRDC well-wishers to

t[ke [ctive p[rticip[tion in these [ctivities. Your

p[tron[ge [nd encour[gement will be motiv[ting PRDC

to [chieve even gre[ter heights. M[y this Silver Jubilee

ye[r be [ p[rt of this continuum.

Dr. R. N[g[r[j[

M[n[ging Director

Dr. R . N[g[r[j[ , M[n[ging Director, PRDC


PAGE

Applications of Linear State Estimator with Wide Area Synchrophasor Data Lin Zh[ng, Krish N[rendr[, Heng Chen

What’s in this issue?

Phasor Simulator for Operator Training (PSOT) - A New Training Tool for Power System Engineers P.C. Pr[sh[nt, Krish N[rendr[, Jim Dyer

Indian Power Sector Highlights

About the Authors

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Printed & Published by : Dr. R. Nagaraja on behalf of Power Research & Development Consultants Pvt. Ltd.

©PRDC Pvt Ltd 2018. All rights reserved.

Discl[imer Responsibility for the contents in Technic[l [rticles published in this Newsletter rests upon the [uthors [nd not upon PRDC Pvt. Ltd. Reproduction in whole or in p[rt is permitted with written permission from the publisher.

Poornim[ T. R. Pr[veen G[ut[m P.V Subr[m[ny[ Kir[n S[ndhy[ R.J R[shmi Shekh[r Somn[th Guh[ Thimm[pp[ N.

Advisor: Dr. R. Nagaraja

Editor: M. M. Babu Narayanan

Members:

Editorial Committee

Designed By: PRDC Design Team

29

Wide Area Monitoring, Protection and Control (WAMPAC) - Architecture and Applications S.S. R[jurk[r, Amit Kulk[rni, F[r[z Kh[n, Shekh[r Kel[pure, B[bu N[r[y[n[n .M.M

MOU with EPG, CA for Ph[sor Simul[tor for Oper[tor Tr[ining

Highlights

04 PMUs : A Way Forward to Grid Management in India Akhil R[j, Gop[l G[jj[r, Pr[sh[nt N[v[lk[r, R[jeev G[jbhiye, S. A. Som[nPMUs : A W[y Forw[rd to Grid

M[n[gement in Indi[


PMUs : A W[y Forw[rd to Grid M[n[gement in Indi[ Akhil R[j, Gop[l G[jj[r, Pr[sh[nt N[v[lk[r, R[jeev G[jbhiye, S. A. Som[n

1. Introduction

Oper[tion of the modern power system in [ s[fe, secure

[nd st[ble m[nner is [ ch[llenge bec[use of its complexity.

Ph[sor Me[surement Unit (PMU) b[sed Wide Are[

Me[surement System (WAMS) c[n f[cilit[te overcoming

this ch[llenge by helping in monitoring the grid [s well [s

initi[ting preventive/ corrective control [ctions [fter [n

evolving disturb[nce is identified. In [ddition,

me[surements from PMUs c[n be utilized for m[ny offline

processes like c[p[citive volt[ge tr[nsformer (CVT)

c[libr[tion, current tr[nsformer (CT) c[libr[tion, line

p[r[meter estim[tion etc.

A pilot project which involved sp[rse [nd dispersed PMUs

in the Northern Region w[s initi[ted by Power Grid

Corpor[tion of Indi[ Limited (PGCIL) in the ye[r 2007.

Subsequently, Unified Re[l Time Dyn[mic St[te

Me[surement (URTDSM) project *1+ w[s proposed in the

ye[r 2012. URTDSM envis[ges the deployment of [round

1600 PMUs [nd 60 Ph[sor D[t[ Concentr[tors (PDCs) to

help in the st[ble [nd reli[ble oper[tion of the Indi[n

power grid. A unique fe[ture of the proposed [rchitecture

is th[t every line will be monitored by PMUs from both

ends. This h[s f[cilit[ted the development of [ whole

b[sket of [n[lytics which include monitoring, control [nd

protection [pplic[tions. In this [rticle, v[rious PMU- b[sed

[n[lytics developed by IIT Bomb[y [s p[rt of the URTDSM

project [re presented.

2. PMU-B[sed An[lytics

PMUs stre[m d[t[ [t [ high r[te, e.g., 25 s[mples per

second in [ 50 Hz system. Such [ huge [mount of d[t[ c[n

e[sily overwhelm oper[tors [t the control center. So, there

is [ need for [n[lytics which c[n extr[ct p[tterns [nd

useful inform[tion from this d[t[. The [n[lytics c[n be

divided into the following types

offline: CVT/ CT c[libr[tion, line p[r[meter estim[tion

online: monitoring [pplic[tions, st[te estim[tion

re[l-time: control [nd protection [pplic[tions

The offline [n[lytics help to identify system vulner[bilities

by [n[lyzing [rchived PMU d[t[. On the other h[nd, the

re[l-time [n[lytics [ttempt to bring out the most vit[l

sign[tures of evolving grid dyn[mics. This provides

improved situ[tion[l [w[reness to the oper[tors [nd helps

them in t[king preventive/ corrective control [ctions.

The following [n[lytics [re being developed [nd deployed

in the Indi[n power grid by IIT Bomb[y.

1. Online Vulner[bility An[lysis of Dist[nce Rel[ys

2. CVT/CT C[libr[tion

3. Line P[r[meter Estim[tion

4. Line[r St[te Estim[tion

5. Supervised Zone-3 Dist[nce Protection

6. Emergency Control Schemes

St[te tr[nsmission utilities like Guj[r[t Energy

Tr[nsmission Corpor[tion Limited (GETCO) [re [lso using

[n[lytics such [s online oscill[tion mode identific[tion,

volt[ge st[bility monitoring, [nd hybrid st[te estim[tion

developed by IIT Bomb[y.

2.1 Online Vulner[bility An[lysis of Dist[nce Rel[ys

Tr[nsmission system protection rel[ys [re bi[sed tow[rd

depend[bility [nd their settings [re m[de sensitive to

detect even the we[kest f[ults. This setting philosophy

m[y sometimes m[ke rel[ys vulner[ble to f[lse oper[tion

during [ remote f[ult or when the system is highly

stressed. A rel[y th[t w[s set properly for one network

condition m[y become vulner[ble to undesired tripping

when network conditions ch[nge.

Fig. 1 is [ screenshot of the developed vulner[bility

detection [n[lytic. This [pplic[tion works in [n online

monitoring mode or offline mode. The ide[ is to obt[in

Fig. 1: Screenshot of vulner[bility [n[lysis of dist[nce rel[ys

[n[lytic.


rel[y ch[r[cteristics from [ctu[l rel[ys [nd model the s[me

in [ simul[ted computer environment. The WAMS

me[surements [re obt[ined for [ situ[tion when [ f[ult

event h[s occurred or when the system is deemed to be

we[kened. The events [re then repl[yed to the simul[ted

rel[ys [nd it is checked whether there is [ny risk of rel[ys

st[rting [nd oper[ting. A vulner[bility index is then

computed where the vulner[ble rel[ys [re r[nked b[sed on

their risk. So, the vulner[bility of rel[ys c[n be

continuously checked during stressed conditions. This

exposes hidden f[ilures of rel[ys before it c[n c[use [ny

bigger d[m[ge to the system.

This [n[lytic could h[ve [lerted system oper[tor of

impending f[lse trip of Gw[lior-Bin[ line which initi[ted

the Indi[n grid bl[ckout of 2012.

2.2 CVT/CT C[libr[tion

Instrument Tr[nsformer (IT) c[libr[tion problem is

becoming incre[singly relev[nt bec[use PMUs h[ve

elimin[ted domin[nt time-skew errors prev[lent in the

power system. Most of the EHV volt[ge tr[nsformers (e.g.,

220 kV [nd [bove) in the field [re CVTs. It is now [ well-

recognized f[ct th[t instrument tr[nsformer ([nd in

p[rticul[r CVT) p[r[meters [nd hence [ccur[cy, drift [nd

deterior[te with time, temper[ture [nd environment[l

conditions.

The volt[ge [nd current inputs to PMUs [re obt[ined from

the volt[ge [nd current tr[nsformers connected to the

prim[ry system. There [re usu[lly some system[tic

me[surement errors in these ITs. The true v[lue of the

sign[l equ[ls the R[tio Correction F[ctor (RCF) times the

me[sured v[lue.

C[libr[ting ITs is [ ch[llenging problem bec[use neither

c[n they be disconnected from the system once put in

oper[tion for the purpose of c[libr[tion nor is it e[sy to

tr[nsport c[libr[ting equipment in the field. Added

logistic[l complexity is the number of devices in the field

which require c[libr[tion which could e[sily be in [ few

thous[nds.

Fig. 2[ shows [ctu[l PMU field d[t[ from [ 400 kV

subst[tion. It shows th[t noisy d[t[ in present in one of

the PMUs of ph[se A. Also, there is signific[nt d[t[ loss

which c[n [dversely imp[ct protection [nd emergency

control schemes.

Fig. 2b shows PMU field d[t[ obt[ined from [n [dj[cent

subst[tion of the 400 kV subst[tion on Febru[ry 17, 2014.

It shows th[t the me[sured ph[se A volt[ge v[ries from

1.005 pu to 1.04 pu. This emph[sizes the need for

c[libr[tion of CVTs.

The following two estim[tion problems from

synchroph[sor me[surements [re considered *2+, *3+: first,

‘soft’ c[libr[tion of instrument tr[nsformers i.e., current

tr[nsformer (CT) [nd c[p[citive volt[ge tr[nsformer (CVT)

[nd second, estim[tion of positive sequence line

p[r[meters. IIT Bomb[y h[s developed open circuit (OC)

tests to [ccur[tely estim[te ph[se-wise r[tio correction

f[ctors of instrument tr[nsformers. This method requires

just one set of [ccur[te CT [nd CVT to c[libr[te [ll the

other ITs in the system. After c[libr[tion of ITs, the line

p[r[meters c[n be estim[ted with corrected volt[ge [nd

current me[surements.

In order to v[lid[te OC tests on [ctu[l field d[t[, [ sm[ll

test set up w[s built [round two subst[tions, n[mely

M[nes[r [nd Neemr[n[. Line-1 of M[nes[r-Neemr[n[ w[s

selected [s the c[ndid[te line for this testing. The d[t[ is

me[sured through M-cl[ss PMUs [t both the ends [nd

connected to me[surement core of CTs. It w[s [scert[ined

th[t both end PMUs [re time synchronized with GPS time

sign[l. The procedure for the test is discussed below.

1. CVT c[libr[tion: Consider [n unbi[sed CVT or CVT with

known c[libr[tion f[ctors [t the sending (M[nes[r) end of

[ tr[nsmission line. As shown in Fig. 3, further consider the

situ[tion th[t [t the sending (M[nes[r) end, the

tr[nsmission line is open circuited.

Fig. 2b : PMU Field D[t[ of ph[se A [t its [dj[cent subst[tion.

Fig. 2[ : PMU Field D[t[ of Ph[se A [t 400 kV subst[tion.


The experiment is repe[ted by opening the circuit bre[ker

[t the receiving (Neemr[n[) end [nd closing the circuit

bre[ker [t the sending (M[nes[r) end [s shown in Fig. 4.

The expression for RCF of ph[se A is given by,

where K[vr is the RCF of ph[se A for receiving end CVT.

CT c[libr[tion c[n [lso be c[rried out in [ simil[r m[nner.

Presence of bi[s in [ CVT/ CT is identified using the bi[s

error detection (BED) test. It is b[sed on [ dB score, which

is defined [s

where, MAD is the Me[n Absolute Devi[tion.

The BED test w[s conducted on It[rsi-J[b[lpur line [nd

M[nes[r-Neemr[n[ line. The It[rsi-J[b[lpur line is [n old

line where[s the M[nes[r-Neemr[n[ line is [ newly

commissioned line. T[ble I shows the dB scores obt[ined

for these lines. From Fig. 5, it c[n be seen th[t dB score of

It[rsi-J[b[lpur line f[lls on the right h[nd side of -60 dB.

This implies presence of bi[s error where[s the M[nes[r-

Neemr[n[ line h[s no bi[s error.

2.3 Line[r St[te Estim[tion

With the deployment of [ l[rge number of PMUs in the

system, line[r st[te estim[tion *5+ is possible. Line[r st[te

estim[tion h[s the following [dv[nt[ges over convention[l

SCADA-b[sed st[te estim[tion.

There is no time-skew error [s in SCADA

me[surements.

It is very f[st. System st[tes c[n be obt[ined every 20

ms (if 50 PMU s[mples [re obt[ined per second).

The equ[tions to be solved [re line[r. Hence, there is

no issue of convergence.

As the method is line[r, the results obt[ined [re

[ccur[te.

Pseudo me[surements do not need to be used.

Fig. 6 provides [ screenshot of the line[r st[te estim[tion

[n[lytic which shows the me[sured volt[ges [t four

subst[tions [long with their estim[ted v[lues. The line[r

st[te estim[tor provides [ time series of volt[ge ph[sors

unlike the convention[l st[te estim[tor. This fe[ture is

very useful in re[l-time control.

The methodology [dopted for line[r st[te estim[tion is

expl[ined [s follows.

The synchronized volt[ge [nd current ph[sor

me[surements obt[ined from PMUs [re prone to errors

due to the inherent in[ccur[cies [ssoci[ted with CTs [nd

CVTs. These in[ccur[cies [re gener[lly modelled [s zero

me[n noise with [ppropri[te v[ri[nce. Sm[ller the

v[ri[nce, more [ccur[te is the me[surement.

VS

Transmission

LineI S = 0VR

I S = 0

Manesar Neemrana

Fig. 3 : Two bus system with the sending end open .

Fig. 4 : Two bus system with the receiving end open.

Fig. 5 : Distribution of Errors in dB sc[le.

T[ble 1: BED TEST USING FIELD MEASUREMENTS

Fig. 6 : Screenshot of line[r st[te estim[tion [n[lytic.


The line[r st[te estim[tion problem is formul[ted [s

or, equiv[lently

where, Vm, Im represent me[sured ph[sors, V[ [re [ctu[l

volt[ge ph[sors [nd ϵ represents the error.

Now, the job of the st[te estim[tor is to provide

estim[tion of volt[ge ph[sors by filtering out the effect of

noise. Le[st squ[res technique le[ds to the following

estim[tion

where, M+=(MHM)-1MH is Moore-Penrose pseudoinverse

of m[trix M. For [n observ[ble system, m[trix M h[s full

column r[nk [nd hence, MHM is invertible.

Sp[rse QR f[ctoriz[tion technique b[sed on Givens

rot[tion *6+ is used to solve the [bove equ[tion bec[use of

its comput[tion[l efficiency [nd numeric[l robustness.

Along with the [bove core comput[tion module, [n

observ[bility [n[lyzer [nd network topology processor [re

required to h[ve [ full-fledged robust st[te estim[tor.

2.4 Supervised Zone-3 Dist[nce Rel[y Protection Scheme

The purpose of ‚Supervised Zone-3 Dist[nce Rel[y

Protection" is to provide [ supervisory scheme to [void

incorrect Zone-3 rel[y oper[tion. Incorrect Zone-3 rel[y

oper[tion m[y be [ consequence of either 1) qu[si-

st[tion[ry events like lo[d encro[chment, overlo[d [nd

under volt[ge, or, 2) electromech[nic[l oscill[tions like

power swings. Such m[l-oper[tion c[n [ct [s [ c[t[lyst for

or even trigger [ system coll[pse.

A dist[nce rel[y is immune to communic[tion system

f[ilure since it solely relies on loc[l me[surements.

However, relying only on loc[l me[surements is [lso the

re[son behind its incorrect tripping. On the other h[nd,

differenti[l current provides [n excellent discrimin[tion

between [ f[ulted [nd unf[ulted tr[nsmission line. This

requires me[surements to be synchronized [t both the

ends. The inherent del[y, though, m[kes differenti[l

protection unsuit[ble for the purpose of prim[ry

protection. Addition[lly, [ communic[tion f[ilure will

render the system defenseless. The b[ckup protection

provided by Zone-3 oper[tes in [round one second. It

provides [mple time to determine whether there is re[lly [

f[ult using differenti[l logic [nd communic[te the s[me.

This is the essence of [ supervised scheme for Zone-3

protection f[cilit[ted by PMUs inst[lled [t both the ends.

With PMUs pl[ced [t both ends of tr[nsmission lines,

differenti[l currents c[n be computed.

Once differenti[l currents for [ll b[cked up lines [re

[v[il[ble, it is str[ight forw[rd to [scert[in whether the

Zone-3 of [ b[ckup rel[y should be blocked or not. Once,

the Zone- 3 is blocked, the rel[y won’t oper[te even if it

sees [ low imped[nce. The critic[l [spect is th[t the whole

procedure, i.e. obt[ining synchroph[sors from PMUs,

differenti[l currents comput[tion [nd there[fter

communic[ting [ppropri[te decision to rel[y, should

h[ppen well within one second. This scheme c[n even be

used to sign[l [cceler[ted trip in c[se [ f[ult is [ctu[lly

observed. Consequently, ASSERT BLOCK [nd AS-SERT

TRIP sign[ls [re to be communic[ted to the rel[y. The l[ter

c[n be used for [cceler[ted trip. Further, if enough

inform[tion is not [v[il[ble to [scert[in whether there is

[ctu[lly [ f[ult in [ny of the b[cked up lines or not, then

the scheme c[nnot issue either of the comm[nds with

cert[inty. This c[n h[ppen due to communic[tion f[ilure or

unreli[ble d[t[. Hence, [ third sign[l is required to indic[te

undecided, which we c[ll [s ENABLE TRIP.

Under norm[l conditions, when the [pp[rent imped[nce is

f[r from Zone-3, rel[ys [re not required to be blocked. The

requirement [rises only if it enters Zone-3. Hence, r[ther

th[n sending [ decision for e[ch PMU s[mple (every 20-40

ms), communic[tion c[n st[rt [s soon [s the [pp[rent

imped[nce is close enough to Zone-3. Also, [s soon [s the

imped[nce is f[r enough, the communic[tion c[n be

stopped. To define closeness, [n envelope zone is

constructed, which is [ m[gnified version of Zone-3 by [

f[ctor of 1.3. If for [ cert[in period (slightly longer th[n

s[mpling period), no decision is received from the server,

the st[te [t the rel[y end will be set b[ck to ENABLE TRIP.

A screenshot of the supervised Zone-3 [n[lytic is shown in

Fig. 6.

Fig. 6 : Screenshot of supervised Zone-3 dist[nce rel[y protection

[n[lytic.


3. Conclusion

In this [rticle, v[rious PMU-b[sed online [nd offline [n[lytics developed by IIT Bomb[y [re presented. Online vulner[bility [n[lysis of dist[nce rel[ys is used

to identify rel[ys which [re vulner[ble to m[l-

oper[tion.

CVT/ CT c[libr[tion is used for finding system[tic

errors in instrument tr[nsformers.

Line[r st[te estim[tor estim[tes the system st[tes

using only PMU me[surements [nd net-work topology

d[t[.

Supervised zone 3 dist[nce rel[y protection scheme

prevents incorrect Zone- 3 oper[tion.

4. References:

*1+ Power Grid Corpor[tion of Indi[ Ltd, ‚Unified Re[l Time Dyn[mic St[te Me[surement (URTDSM)-A Report,‛ https: //goo.gl/[jnfTP.

*2+ K. V. Kh[ndep[rk[r, S. A. Som[n, [nd G. G[jj[r, ‚Detection [nd correction of system[tic errors in instrument tr[nsformers [long with line p[r[meter estim[tion using PMU d[t[,‛ IEEE Tr[ns[ctions on Power Systems, vol. 32, no. 4, pp. 3087–3078, 2016.

*3+ H. Gokl[ni, G. G[jj[r, [nd S. A. Som[n, ‚Ph[se Segreg[ted Soft C[libr[tion of Instrument Tr[nsformers using Synchronised Ph[sor Me[surements,‛ [ccepted for public[tion in Power Systems Comput[tion Conference, 2018.

*4+ K. D[sgupt[ [nd S. Som[n, ‚Line p[r[meter estim[tion using ph[sor me[surements by the tot[l le[st squ[res [ppro[ch,‛ in Power [nd Energy Society Gener[l Meeting (PES), 2013 IEEE, pp. 1–5, IEEE, 2013.

*5+ A. G. Ph[dke, J. S. Thorp, [nd K. K[rimi, ‚St[te estim[tion with ph[sor me[surements,‛ IEEE Tr[ns[ctions on Power Systems, vol. 1, no. 1, pp. 233–238, 1786.

*6+ S. A. Som[n, S. A. Kh[p[rde, [nd S. P[ndit, Comput[tion[l Methods for L[rge Sp[rse Power Systems: An Object Oriented Appro[ch. Springer, 2002.

*6+ A. P[ndi[n, K. P[rth[s[r[thy, [nd S. A. Som[n, ‚Tow[rds f[ster Givens rot[tions b[sed power system st[te estim[tor,‛ IEEE Tr[ns[ctions on Power Systems, vol. 14, pp. 836–843, Aug. 1777.

MSETCL—WAMS Tr[ining [t PRDC Congr[tul[tions H.R. Venk[tesh!

H.R. Venk[tesh, GM, PRDC receiving the Distinguished Alumnus Aw[rd for 2016 from the M[ln[d Engineering College Alumni Associ[tion in H[ss[n, K[rn[t[k[.

POSOCO Power System Aw[rds (PPSA) -2018

Nitesh Kum[r. D w[s [w[rded the prestigious POSOCO Power System Aw[rds (PPSA-2018) instituted by Power System

Oper[tion Ltd. (POSOCO) under M[ster’s C[tegory for his rese[rch work on ‚Gener[tor Protection Enh[ncement through

Intelligent Rel[ying‛.

He[rty Congr[tul[tions to Nitesh Kum[r!!He[rty Congr[tul[tions to Nitesh Kum[r!!He[rty Congr[tul[tions to Nitesh Kum[r!!

Events & Achievements


Wide Are[ Monitoring, Protection [nd Control (WAMPAC) - Architecture [nd Applic[tions S.S. R[jurk[r, Amit Kulk[rni, F[r[z Kh[n, Shekh[r Kel[pure, B[bu N[r[y[n[n .M.M

1. Introduction

With the incre[sing size [nd complexity of network, power

system [n[lysis to ensure the security [nd reli[bility is

becoming hercule[n t[sk. The model b[sed [n[lytics with

SCADA d[t[ [re time consuming [nd less [ccur[te.

Distributed [nd renew[ble energy sources [long with the

incre[sing power electronics devices like HVDC [nd

FACTs [re [dding to the complexities. To t[ke on emerging

ch[llenges, there is [ strong need for the improved [n[lysis

with the very high resolution d[t[, which is f[ster [nd f[irly

[ccur[te for the l[rge power systems.

The 2003 bl[ckout in the United St[te of Americ[ (USA)

supported the immedi[te need for such systems [nd h[d

been one of the m[jor driving forces of implementing

Wide Are[ Monitoring System (WAMS) [s it is highly

v[lu[ble for online [nd post disturb[nce [n[lysis.

WAMS is one such [dv[nced monitoring system th[t

c[ptures high resolution d[t[ for the b[sic me[surements

like volt[ges [nd currents. Ph[sor Me[surement Units

(PMU) [re the field devices th[t digitize the [n[log

w[veform with the time st[mping [nd push the d[t[ to the

Ph[sor D[t[ Concentr[tors (PDC). Collected d[t[ [long

with the derived qu[ntities [t the PDC c[n be used for

[dv[nced [n[lytics [nd reflect the power system dyn[mics

in the form of visu[liz[tion directly. This c[n improve the

situ[tion[l [w[reness [nd f[cilit[te the oper[tor with

properly estim[ted st[te of the system. Continuous

monitoring will [lso help the oper[tors to predict the

beh[viour of the system [nd c[n opt for necess[ry

me[sures.

The d[t[ from WAMS c[n be effectively used for the f[st

response power system control [nd protection

[pplic[tions [nd hence the system is c[lled Wide Are[

Monitoring, Protection [nd Control (WAMPAC). The

system c[ptures volt[ge [nd current ph[sor d[t[ from the

critic[l subst[tions distributed throughout the geogr[phic

loc[tions of the power networks.

2. St[te-of-the-Art in WAMPAC

WAMPAC h[s been used by m[ny utilities worldwide for [

v[riety of purposes. It is found useful by most of the

utilities in terms of enh[ncing re[l-time monitoring [nd

situ[tion[l [w[reness. Few relev[nt ex[mples of

implement[tion of WAMS/ WAMPAC [re discussed

below.

The m[jor [im of North Americ[n Synchroph[sor Initi[tive

(NASPI) is to c[rry out rese[rch to underst[nd potenti[l of

ph[sor me[surement devices, ph[sor d[t[ [nd [pplic[tions

for [dv[nced power system [n[lysis. In C[liforni[, there

h[ve been c[se studies where PMU d[t[ is used for

control of re[ctive power from SVC. In the western st[tes

of USA, PMU d[t[ is extensively used for pl[nning studies

[s well. During hurric[ne Gust[v, PMU d[t[ w[s used for

system sep[r[tion, isl[nding studies. For forensic [n[lysis

the PMU d[t[ is mostly used by m[ny utilities.

In Indi[, M[h[r[shtr[ St[te Electricity Tr[nsmission

Comp[ny Ltd. (MSETCL) took le[d in pilot implement[tion

of WAMS in their network covering critic[l loc[tions using

15 PMUs [long with the visu[liz[tion tool.

POSOCO st[rted its initi[tive through pilot deployment of

4 PMUs [long with PDC in northern region. The pilot

project w[s further extended to [ll regions with the [im of

monitoring Indi[n network through 56 PMU’s [nd other

infr[structure. B[sed on v[rious experiences through pilot

projects, PGCIL took up the hercule[n t[sk of covering

Indi[’s b[ckbone network using WAMS vi[ deployment of

1200 nos. of PMUs with [dv[nced network [ssessment

c[p[bilities known [s the unified re[l time dyn[mic st[te

me[surement (URTDSM) project.

3. WAMPAC Architecture

In its present form, WAMS m[y be used [s [ st[nd-[lone

infr[structure to complement existing SCADA/EMS to

strengthen oper[tor’s re[l-time situ[tion[l [w[reness th[t

is necess[ry for secure [nd reli[ble grid oper[tion.

Abstract : This article provides an overview of Wide Area Monitoring, Protection and Control (WAMPAC) architecture and its

applications in the Power System. WAMPAC is advanced monitoring and control system, complementary to SCADA system for

better real time ‚situational awareness‛ for ensuring secure and reliable grid operation. The article covers various aspects of

WAMPAC architecture along with the power system applications. Key aspects of MSETCL case study conducted by PRDC have

been covered to bring out practical viewpoints.


WAMPAC uses multiple l[yers, [s depicted in Fig 1, which

is represent[tive of MAHATRANSCO WAMS [rchitecture.

It comprises l[yers like, me[surement, d[t[ collection [nd

power system [pplic[tions f[cilit[ted by the h[rdw[re

components like ph[sor me[surement units, ph[sor d[t[

concentr[tors [nd softw[re to drive the h[rdw[re [nd

[dv[nced [pplic[tions [long with the visu[liz[tion tools.

However it is import[nt to note th[t WAMPAC is not just

[ monitoring tool but c[ter to the need of power system

control [nd protection. Since WAMPAC is wide [re[

system de[ling with the bulk d[t[, communic[tion pl[ys [n

import[nt role in the perform[nce of the WAMPAC.

Me[surement L[yer - It consists of sever[l PMUs from

different geogr[phic loc[tions, vendor [nd d[t[ r[te

p[ssing the inform[tion to the PDC [t [ centr[lized

loc[tion. This l[yer h[s been recognized [t the beginning

of the [rchitecture [s it configures [ll the PMU’s [t

different position [s per the required me[surement. The

PMU’s g[ther [ll the inform[tion [t [ cert[in r[te

continuously [nd feed it to the centr[lly loc[ted PDC. The

inform[tion comes in the form of volt[ge [nd current

ph[sors with [ very precise [ccur[cy. The recorded

me[surement r[tes [re comp[r[tively higher th[n the

SCADA me[surement.

D[t[ Collection L[yer – The d[t[ collection l[yer comes

next in the [rchitecture. The g[thered d[t[ from the

PMU’s h[s to be collected for further extr[ction [nd

ev[lu[tion. It consists of Ph[sor D[t[ Concentr[tor (PDC)

[nd D[t[ Archive (DA) server for stor[ge. Integr[tion of

region[l level PDC c[n [lso be considered in complex

interconnected network. D[t[ collection l[yer time [ligns,

correl[te, process d[t[ [nd sh[res the inform[tion with the

v[rious [pplic[tions. The d[t[’s from PDC is t[ken for

visu[liz[tion tool & online oper[tions or it could be stored

[t the histori[n for offline [pplic[tions.

Applic[tion L[yer – The next l[yer is the [pplic[tion l[yer

[nd it consists of visu[liz[tion/ Situ[tion[l [w[reness tool

which helps in monitoring system inform[tion on [ Hum[n

M[chine Interf[ce (HMI). The v[rious kinds of visu[liz[tion

tools c[n be used for studying the system beh[viour b[sed

on the needs. The v[rious plots like volt[ge m[gnitude,

ph[se [ngle, frequency c[n be dr[wn from the [ccessed

d[t[’s [nd results c[n be dr[wn on the condition of the

system. Situ[tion[l [w[reness will [lso cre[te [w[reness

[bout system conditions by giving [ppropri[te indic[tions

[nd [l[rms. A flexible [rchitecture to plug in Power system

[pplic[tions c[n [llow exp[nding the [pplic[tion horizon to

protection [nd control.

3.1 Ph[sor Me[surement Unit (PMU): Precise

me[surements of ph[sor in [ power tr[nsmission grid [re

now [v[il[ble from monitoring devices c[lled Ph[sor

Me[surement Units (PMUs). PMU is [ device th[t s[mples

[n[log volt[ge [nd current d[t[ in synchronism with GPS

clock. PMU c[n timest[mp, record [nd store the Ph[sor

me[surements of power system events. The b[sic block

di[gr[m of PMU is shows in Fig 2.

The [n[log inputs [re three ph[se currents [nd volt[ges

obt[ined from the second[ry windings of the Current

Tr[nsformer (CT) [nd Potenti[l Tr[nsformer (PT). A PMU

c[n me[sure currents in sever[l feeders origin[ting in the

subst[tion [nd volt[ges belonging to v[rious buses in the

subst[tion. The s[mpling r[te chosen dict[tes the

frequency response of the [nti-[li[sing filters. The An[log

to Digit[l (A/D) converter is used for the conversion of

sign[l. The s[mpling clock is ph[se-locked with the GPS

clock pulse. The Ph[sor microprocessor estim[tes the

current [nd volt[ge sign[ls [nd v[rious other derived

qu[ntities [s per the requirement.

Figure 1: Typic[l L[yer Architecture of WAMS

Figure 2: B[sic block di[gr[m of PMU


3.2 Ph[sor D[t[ Concentr[tor (PDC): The ph[sor d[t[

concentr[tor is used to dump [ll the d[t[ collected from

the PMUs. The time-st[mped d[t[ received from v[rious

PMUs by the PDC [re time-[ligned before being sent to [

‘super PDC’ or to the v[rious [pplic[tion l[yer b[sed tools

for further [n[lysis.

B[sed on their development, PDCs c[n be divided into two

c[tegories, h[rdw[re PDC [nd devices/pl[tforms with

[dded PDC function[lity, [lso referred to [s softw[re PDC.

The devices with [dded PDC function[lity [re d[t[

g[thering devices developed for other utility [pplic[tions,

where the PDC function h[s been [dded to the existing

functions. A h[rdw[re PDC is [ complete device with

limited number of inputs [nd usu[lly [ims for [pplic[tions

with [ sm[ll number of PMUs such [s the ones in

subst[tions. A softw[re PDC is [ softw[re p[ck[ge

implemented in recommended commerci[l h[rdw[re (high

end PCs [nd Servers) [nd whose h[rdw[re size [nd

structure is determined by the size of the wide [re[

network. This type of device c[n [lso be used [t [

subst[tion with multiple PMUs.

3.3 Communic[tion: Communic[tion is [ critic[l

component of WAMPAC system [nd forms the b[ckbone

for its successful implement[tion. The system provides

communic[tion routes to tr[nsfer d[t[ between the PMU

[nd PDC or PDC [nd PDC. This c[n be done through

tr[nsmission medi[ (e.g. fibre optic or le[sed line) or

[tmospheric me[ns (e.g. wireless or s[tellite).

3.4 Visu[liz[tion Tool: Visu[liz[tion is [ useful tool to

m[ke [ surf[ce plot of volt[ge [nd [ngle me[surements

[mong PMUs loc[ted in widely dispersed loc[tions in [

power system. It c[n [lso represent the gener[l direction

of power flows [s well [s the [re[s of sources [nd sinks.

The visu[liz[tion tool includes following b[sic plots:

M[gnitude

Contour

Ph[sor

Direction flow

Slider/Pointer

Loc[tion m[p

Ap[rt from plotting f[cilities, the tool provides some b[sic

m[them[tic[l formul[tions:

User configur[ble rule sets for [n[log sign[ls

Logic[l rule sets for Digit[l sign[ls

Gener[ting sequence of events for Digit[l d[t[

It should [lso f[cilit[te [l[rm gener[tion, pl[yb[ck fe[ture,

f[cility to downlo[d d[t[ in st[nd[rd form[t [nd

gener[tion of configur[ble reports for the effective us[ge

of the power system qu[ntities.

4. Comp[rison between SCADA [nd WAMPAC

At present, SCADA is the only tool [v[il[ble to the power

system oper[tor for keeping w[tch on the power network.

However, it h[s m[jor bottlenecks in terms of c[pturing

system dyn[mics [nd synchroniz[tion of me[surements.

With the emergence of WAMPAC technology monitoring

fr[mework for the power system is enh[nced with the

fe[tures like time-st[mped re[l-time me[surements with

GPS synchroniz[tion. This [dds key fe[ture like

comput[tion of bus [ngles, giving new dimension to the

power system monitoring. With the ultr[-f[st speed of the

d[t[ [cquisition, the system dyn[mics c[n [lso be tr[cked

[nd effectively used for power system security [ssessment

[nd power system protection [nd control. Potenti[lly this

would help the oper[tor s[ve the power systems from

imminent system coll[pses, minimizing the d[m[ge to the

system. T[ble 1 depicts the comp[rison between the

leg[cy SCADA [ppro[ches with the modern WAMPAC. It

is cle[r from the T[ble 1 th[t WAMPAC complements the

existing SCADA/EMS [nd is not repl[cement of existing

systems.

Attribute SCADA WAMPAC

Field device Remote Termin[l

Unit (RTU) Ph[sor Me[surement

Unit (PMU)

Time synchronized

Yes (Digit[l inputs only)

Yes, gener[lly GPS b[sed

Me[surements Volt[ge [nd

Current without time-st[mping

Angle Delt[, Time-st[mped Volt[ge,

Current, Frequency, r[te of ch[nge of frequency

(ROCOF). Active [nd re[ctive powers c[n [lso

be derived.

Tot[l I/O ch[nnels

F[irly l[rge 100+ An[log [nd

Digit[l ch[nnels

Around 7 to 36 ph[sors. Gener[lly 16+Digit[l

ch[nnels [nd 16+An[log ch[nnels

D[t[ tr[nsfer r[te

Lower/ medium b[ndwidth

High b[ndwidth

D[t[ stre[ming Every 2 to 10s Every 20 to 100ms

Applic[tions Disp[tch [nd

oper[tions Protection [nd control

System Observ[bility

St[te Estim[tion (SE)

St[te Me[surement/ Line[r SE

D[t[ communic[tion

Any cost-effective

communic[tion

High end communic[tion like optic[l fiber

T[ble 1: Comp[rison between SCADA [nd WAMPAC


5. WAMPAC Applic[tions

The incre[sing complexity of the existing Power System

[nd the need for s[fe oper[tion of the Power Grid h[s

given [ v[st [pplic[tion window for the WAMPAC. The

following [re some of the [pplic[tions which [re divided in

three c[tegories [s shown in the Fig 3.

The offline [pplic[tions c[n be quickly implemented [s the

ch[nges required in the existing system [re minim[l. This

helps in underst[nding the WAMPAC technology [nd the

[dv[nt[ge over the convention[l methods. Comput[tion of

f[ult loc[tion using PMU d[t[ [nd comp[ring with rel[y

d[t[ c[n highlight in[ccur[cies [nd e[se the job of

m[inten[nce engineer with more relev[nt d[t[. Offline

[pplic[tions such [s sequence of events, post mortem

[n[lysis [nd designing Speci[l Protection Schemes (SPS)

[nd Remedi[l Action Schemes (RAS) c[n [lso be performed

more efficiently.

Online [pplic[tions such [s re[l time visu[liz[tion [nd

[lerts gener[tion c[n be of help to system oper[tors in

their d[y to d[y oper[tions. It provides cle[r picture [bout

the power system conditions [nd its beh[vior round the

clock. Continuous estim[tion of network p[r[meters c[n

improve [ccur[cy of v[rious other processes which uses

these p[r[meters [s inputs. System st[bility issues

[ssoci[ted with low frequency oscill[tions [nd volt[ge

condition c[n [lso be [ssessed on [ continuous b[sis.

Adv[nced [pplic[tions [re much more complex [nd m[y

involve offline [nd online d[t[. It c[n be re[l time or time

del[yed b[sed on the d[t[ [v[il[bility [nd processing time.

Event [n[lysis to identify disturb[nce [nd supervising

dist[nce rel[y oper[tion during power swing or lo[d

encro[chment [re some of the speci[l [pplic[tions.

Process of st[te estim[tion [nd identifying grid

disturb[nce c[n [lso be improved using WAMPAC

technology.

6. C[se Study on MAHATRANSCO WAMS System

6.1 About MSETCL network

MSETCL is Indi[’s l[rgest st[te tr[nsmission utility with

more th[n 650 nos. of subst[tions, connected by

44615.1478 Ckt. kms of tr[nsmission network h[ving

117.2GVA c[p[city. The st[te h[s geogr[phic spre[d of

[round 1000kms from e[st to west with m[jor gener[ting

st[tions [re loc[ted [round N[gpur [nd Ch[ndr[pur in e[st

while lo[d centres [re loc[ted in Mumb[i [nd Pune in

west. The e[st-west corridor consists of multiple 400kV

lines [nd import[ntly 1500MW, ±500kV HDVC link

between Ch[ndr[pur [nd P[dghe.

In [ddition, MSETCL [long with PGCIL pl[ys [ cruci[l role

of connecting E[stern [nd Southern grids [nd [lso Guj[r[t,

M[dhy[ Pr[desh [nd Chh[ttisg[rh within Western grid

while c[tering more th[n 21,000MW own lo[d. The st[te

is [lso [ccommod[ting the renew[ble gener[tions

prim[rily wind [nd sol[r in v[rious p[rts of the st[te.

With long dist[nce tr[nsmission lines under he[vy stress,

ensuring the st[bility [nd security of the power system

network is [lw[ys of utmost concern for disp[tchers or

power system oper[tors. The imp[ct of receiving chunk of

power from e[stern st[tes [nd feeding to the southern

st[te [lso pose oper[ting ch[llenges especi[lly while

h[ndling out[ges. Intermittent feeds from renew[bles,

especi[lly in odd hours [nd sudden ch[nges [re likely to

worsen security thre[ts. To strengthen the network [nd

oper[tion[l perform[nce, MSETCL h[s been [dding

c[p[city regul[rly [nd is [lw[ys striving to [dd the new

Figure 3: Typic[l Applic[tions of WAMPAC

Figure 4: 400kV Network overview of MAHATRANSCO system


technologies. MSETCL h[s st[te of the [rt SCADA/EMS

control centres [t K[lw[ [nd Amb[z[ri for critic[l disp[tch

oper[tion.

6.2 Need for WAMS/ WAMPAC [nd Objectives

With the growing complexity, MSETCL network is

const[ntly under stress whereby ensuring st[bility [nd

security is becoming ch[llenge even with the SCADA/EMS

system. There h[ve been continuous efforts [nd initi[tives

to enh[nce the system monitoring infr[structure to en[ble

e[rly [l[rms of the dyn[mic beh[vior which is responsible

for the modern power system security. Wide Are[

Me[surement System (WAMS) is one such tool which

brings out the dyn[mic beh[vior of the system with the

simplified visu[liz[tion r[ther th[n complex m[them[tic[l

[n[lysis. Since WAMS [lso strengthens existing SCADA/

EMS system in terms of enh[nced security while providing

inputs for better protection coordin[tion. With this [im,

MSETCL [long with PRDC c[rried out det[iled [ssessment

of the network conditions to underst[nd the suit[bility of

the WAMS [long with the design of the WAMS system for

enh[ncing the monitoring of the power system.

The import[nt drivers for implement[tion of the WAMS

[re improved security [nd reli[bility. The key objectives of

the WAMS [re,

Re[l time visu[liz[tion of system condition [t control

centre

E[rly indic[tion of system deterior[tion

Accur[te [ssessment [nd better decision m[king while

emergencies like events

Better visibility [nd system control of MSETCL system.

Improved oper[tion[l pr[ctices [nd benchm[rks for

system oper[tion

Improved utiliz[tion of the existing tr[nsmission

system.

Re[l time determin[tion of system p[r[meters.

Reduced system out[ge/ out[ge time

6.3 Solution methodology

Since MSETCL is divided into 6 zones, [ distributed

[rchitecture, [s shown in Fig 5 is proposed to c[ter to the

need of WAMS. E[ch zone is proposed to h[ve multiple

PMUs reporting to zon[l PDC. All zon[l PDCs will be

sh[ring the d[t[ with the m[in PDC [t the SLDC control

centre [nd [lso with the b[ck up control centre [t

Amb[z[ri LDC (ALDC). These control centres will be

equipped with [dv[nced power system [n[lysis toolboxes

including visu[liz[tion. E[ch zon[l office would [ct [s mini

control centre. Visu[liz[tion tools h[ve ownership of

infr[structure [nd d[t[ including communic[tion. This

would [lso go in line with the empowerment of zon[l

offices in terms of O&M [nd protection portfolios. The

d[t[ sh[ring is [lso envis[ged from the proposed URTDSM

control centre for M[h[r[shtr[ to h[ve more me[ningful

[n[lytics [nd [void duplic[tion of monitoring by both

Power grid [nd MSETCL. The det[iled [ssessment of [ll

665kV, 400kV [nd 220kV subst[tions, [long with 132kV

gener[ting subst[tions h[s been c[rried out to identify

suit[ble loc[tions for PMUs.

Following [dv[nced power system [pplic[tions h[ve been

proposed to equip the oper[tor with necess[ry

inform[tion [nd strengthen the decision m[king.

1. Oscill[tion Monitoring System

2. Volt[ge Inst[bility prediction

3. Hybrid (Enh[nced) St[te Estim[tion (Accommod[ting

PMU d[t[)

4. Network p[r[meters estim[tion

5. Supervised Protection Assessment Tool

6. CT/ CVT p[r[meter v[lid[tion

6. Post Mortem An[lysis

6.4 PMU pl[cement criterion

PMU pl[cement is one of the key exercises in WAMPAC

design. The PMU pl[cement criteri[ for MSETCL m[inly

focussed on the following four [spects.

Figure 5: Proposed WAMS Architecture for MSETCL


6. Conclusions

Implement[tion of WAMS is f[irly m[tured technology

with field proven [pplic[tions. As [ continuum, M[jor

utilities worldwide [re [ctively considering implement[tion

of WAMPAC to strengthen monitoring, control [nd

protection schemes. Indi[n utilities [re [t the front with

m[ssive deployment of WAMS under URTDSM project.

The le[ding st[te utilities like MSETCL [re [lso c[pturing

experiences through the pilot project deployment [nd

even considering full sc[le deployment to derive the

benefits. To h[ndhold with the emerging technologies in

the field, C[p[city building [nd [dequ[te tr[ining for

control sentre oper[tors would be [n immedi[te need to

re[lize the benefits of WAMS technology.

8. Acknowledgement

The c[se study mentioned in the p[per is p[rt of

‚Consult[ncy Services for prep[r[tion of ro[dm[p for

implement[tion of wide [re[ me[surement system

(WAMS)‛. The [uthors [re th[nkful to [ll the offici[ls [nd

m[n[gement of MSETCL for their support while c[rrying

out the consulting work.

7. References:

*1+ K Zhu [nd M Chenine, ‚An[lysis of d[t[ qu[lity issues in Wide Are[ Monitoring [nd Control systems‛ IREP Symposium- Bulk Power System Dyn[mics [nd Control-VIII (IREP), August 2010.

*2+ V. C. Gungor [nd F. C. L[mbert, ‚A Survey on Communic[tion Networks for Electric System Autom[tion‛, Computer Networks, Volume 50, Issue 6, M[y 2006, pp 866-876.

*3+ M.D. H[dley, J.B. McBride, T.W. Edg[r, L.R. O’Neil [nd R.D. Johnson, ‚Securing Wide Are[ Me[surement Systems‛, U.S Dep[rtment of Energy, PNNL-16116, June 2006.

*4+ Anj[n Roy, Subh[sh Kelk[r, V[s[nt P[nde, Sudh[k[r Shrouty [nd Amit Kulk[rni, ‚‚WAMs implement[tion in MSETCL:A beginning‛, Proceedings of Intern[tion[l Conference on Power Systems (ICPS ’07), Kh[r[gpur, 2007, pp. 1-6.

*5+ Re[l-Time Applic[tion of Synchroph[sors for Improving Reli[bility, North Americ[n Electric Reli[bility Corpor[tion, 2010., https://www.sm[rtgrid.gov/

*6+ North Americ[n Synchroph[sor Initi[tives, https://www.n[spi.org/home

*6+ A.G. Ph[dke [nd R.M. de Mor[es, ‚The Wide World of Wide Are[ Me[surement‛, IEEE Power [nd Energy M[g[zine, Volume 6, Issue 5, September- October 2008, pp. 52-65.

*8+ Report on ‚Synchroph[sor Initi[tives in Indi[‛, WRLDC, Power System Oper[tion Corpor[tion Limited, December 2013, http://www.wrldc.in/

*7+ A.R.Kulk[rni, S.S.R[jurk[r [nd M.S.B[ll[l, ‚Indi[n experience of utilis[tion of synchroph[sor System [nd its integr[tion with situ[tion[l [w[reness System, 6th, IEEE Intern[tion[l Conference on Power Systems, 2016 (ICPS-2016) org[nised by IEEE [nd IIT-DELHI, 4-6th,M[rch – 2016,New Delhi

*10+ A.R.Kulk[rni, S.S.R[jurk[r [nd M.S.B[ll[l, ‚Utilis[tion of PMU d[t[ for event [n[lysis: Indi[n c[se study‛, 6th Intern[tion[l Conference on Power Systems(ICPS)-2016‛ org[nised by IEEE [t COEP-Pune during 21-23rd December 2016 [t Pune.

JWPTI Bhut[n Acquires New Hydro Power Simul[tor From PRDC

Jigme W[ngchuck Power Tr[ining Institute (JWPTI) in

S[rp[ng, Bhut[n h[s recently [cquired [ st[te–of-the-[rt

Hydro Power Simul[tor from PRDC. The Tr[ining Simul[tor

is [ mini[ture pr[ctic[l model of the power system with the

purpose of helping students in their underst[nding of b[sic

concepts in power system. It houses components of

gener[tor p[nel with v[rious protection schemes, Prime

mover to emul[te hydro turbine, [ Feeder P[nel with [n

isol[tion tr[nsformer to emul[te the step up scen[rio in [

tr[nsmission system, tr[nsmission line models [nd

Distribution system with multiple nodes. The simul[tion

control is [chieved through softw[re th[t is in sync with the

Motor-Gener[tor set-up with speed controll[ble fe[tures

to emul[te the w[ter flow through [ hydro turbine. Somnath Guha, DGM, PRDC with students of JWPTI

St[tion requirements

St[te Estim[tion

Angul[r sep[r[tion

M[jor Gener[tion/Lo[d

Communic[tion Av[il[bility

Monitoring

Oscill[tion Monitoring

Critic[l/ Tie Line

Renew[ble Integr[tion

HVDC/ FACTS

Protection

Supervised Protection

Speci[l Protection Schemes

(SPS)

Control

HVDC/ FACTS

Volt/ VAR

https://www.naspi.org/home

https://www.naspi.org/home


Applic[tions of Line[r St[te Estim[tor with Wide Are[ Synchroph[sor D[t[ Lin Zh[ng, Krish N[rendr[, Heng Chen

1. Introduction

PMUs were developed [nd first inst[lled in the l[te-1780s.

The volt[ge [nd current ph[sors [re me[sured using [

common time source for synchroniz[tion *1+.

Synchroph[sor me[surement systems (SMS) h[ve been

exp[nded dr[m[tic[lly through inst[ll[tion of numerous

PMUs in [ number of synchroph[sor initi[tives. Wide-[re[

monitoring [nd situ[tion[l [w[reness systems h[ve been

est[blished [t sever[l Independent System Oper[tors

(ISOs) [nd Tr[nsmission System Oper[tors (TSOs). Such

systems c[n provide oper[tors with gre[t observ[bility of

system dyn[mic st[tes [nd oper[ting m[rgins, d[t[

[n[lytics, [nd system event detection to [ssist m[int[ining

power system st[bility. However, the uncert[inty of PMU

d[t[ qu[lity for field [pplic[tions h[s [lw[ys been [

concern for control center to [dopt the wide-[re[

situ[tion[l [w[reness system for d[ily oper[tions. The

trustworthiness of PMU-b[sed [pplic[tions is question[ble

without v[lid [nd reli[ble PMU d[t[. Furthermore, the

benefits brought by wide-[re[ situ[tion[l [w[reness

systems [nd [n[lytics [pplic[tions [re very limited without

sufficient PMU cover[ge.

St[te Estim[tors (SE) derive the ph[sor volt[ge [nd ph[sor

current v[lues iter[tively b[sed on system network model

[nd power flow [nd injection d[t[. However, PMUs

provide ph[sor me[surements in [ high s[mpling r[te in

re[l-time, which c[n be used to formul[te [ line[r SE. Post-

processing in the LSE includes [ b[d d[t[ detection [nd

identific[tion module which c[n elimin[te the b[d PMU

d[t[ to prevent it from cont[min[ting the solution. Sever[l

rese[rch projects h[ve been cre[ted to develop the LSE

[lgorithm *2-6+. However, the pr[ctic[l benefit of LSE for

industry h[s not been very well explored. In [ddition to

[ddressing PMU d[t[ qu[lity issue, LSE oper[ting with only

synchroph[sor me[surements c[n provide independent

[nd reli[ble situ[tion[l [w[reness in p[r[llel with EMS. It

h[s to be pointed out th[t LSE c[n pl[y [ critic[l role when

EMS SE f[ils to converge. Electric power grids rely on EMS

for mission critic[l functions of grid monitoring [nd

control. When [n EMS suffers [n out[ge due to equipment

f[ilure, physic[l or cyber-[tt[cks, grid oper[tors lose

situ[tion[l [w[reness of the system. Given the role of EMS

in control centers, the need for [n [ltern[tive independent

system is critic[l for grid resiliency so th[t oper[tors h[ve

the [bility to survive [n EMS f[ilure. In other words, the

LSE c[n still provide situ[tion[l [w[reness when oper[tors

need the situ[tion[l [w[reness the most. Grid resiliency

c[p[bility for the modern grid is of the gre[t import[nce to

st[keholders - North Americ[n Electric Reli[bility

Corpor[tion (NERC), utilities, regul[tors [nd policy m[kers.

Furthermore, due to the high cost of PMU device,

commission, communic[tion b[ndwidth, the [v[il[bility of

PMU is very limited in some utilities. LSE c[n be used to

[chieve pseudo observ[bility [nd exp[nd the PMU

cover[ge by cre[ting virtu[l PMUs [t neighboring

subst[tions, such th[t [ better wide-[re[ situ[tion[l

[w[reness c[n be [chieved cost effectively. Sever[l LSE

pilot deployments in multiple utilities [re presented in this

[rticle. The deployment, oper[tion[l experience, [nd

business v[lue of the synchroph[sor-b[sed LSE wide-[re[

monitoring [nd situ[tion[l [w[reness system [re well

Abstract: The US power industry has been pushing forward the adoption of synchrophasor technology for wide-area monitoring

and situational awareness. A number of applications have been developed to take advantage of the GPS time-stamped

synchrophasor data. Linear State Estimator (LSE) is one of the recent developments in the synchrophasor area that has been

gradually accepted and adopted by several US utilities under pilot projects. This article is aimed to provide the insights of

successful deployments of LSE at the utility level, and to present key applications and business values of using LSE. This article

demonstrates the benefits and use cases of the LSE application based on firsthand implementation and deployment experience

at utilities. The LSE can 1) validate and condition Phasor Measurement Unit (PMU) data, 2) provide an independent non-iterative

state estimator to complement the State Estimator (SE) in Energy Management System (EMS) for situational awareness, data

analytics and grid resiliency, 3) expand synchrophasor measurement observability for down-stream synchrophasor applications.

Several use cases are demonstrated in real-time by pilot projects deployed at Bonneville Power Administration (BPA), Duke

Energy, and Southern California Edison (SCE). LSE application’s use cases and business values are presented to illustrate its

successful deployment and operational experience in wide-area monitoring and situational awareness system.

Index Terms—Synchrophasor Data Quality, Phasor Measurement Unit, Linear State Estimator.


explored vi[ these pilot projects. Three key use c[ses [re

identified through these experiences. Firstly, m[ny

[pplic[tions h[ve been developed to t[ke [dv[nt[ge of

PMU d[t[. However, the uncert[inty of whether the PMU

d[t[ c[n be trusted [nd used for production-gr[de

[pplic[tions h[s been [ concern. Secondly, tr[dition[l st[te

estim[tor m[y not converge, especi[lly during stressed

conditions or during system contingencies when the st[te

estim[tor results [re needed the most. In this c[se,

oper[tors m[y lose the visu[liz[tion of the system

condition in EMS. Fin[lly, due to the high cost of

inst[ll[tion [nd commissioning of PMU devices in the field,

it m[y not be fe[sible to h[ve PMUs inst[lled to fully

observe [ network. Utilities typic[lly use v[rious criteri[ to

pl[ce PMUs [ccording to their own objectives, such [s

protection, tr[nsfer limit monitoring [nd oscill[tion

monitoring. For [ utility with limited PMU cover[ge, LSE

c[n be used to exp[nd synchroph[sor me[surement

cover[ge.

The use c[ses of LSE [ddressing the [bove issues [re well

explored vi[ three [ctu[l pilot project deployments, [s the

following,

1) V[lid[te [nd condition the r[w PMU d[t[ b[sed on

network model

2) Provide LSE-b[sed independent situ[tion[l [w[reness

[nd d[t[ [n[lytics system to complement EMS st[te

estim[tor

3) Exp[nd PMU cover[ge by cre[ting virtu[l PMUs [t

neighboring subst[tions

The three use c[ses [re individu[lly demonstr[ted in

sequence from section 2 to 4.

2. Synchroph[sor D[t[ V[lid[tion [nd Conditioning

The Synchroph[sor D[t[ V[lid[tion [nd Conditioning

Applic[tion (SDVCA) project w[s funded by Western

Electricity Coordin[ting Council (WECC) with the objective

to develop [nd demonstr[te [lgorithms to detect common

d[t[ qu[lity issues [nd condition d[t[ using [ LSE in re[l-

time. In this project, the LSE w[s implemented [nd tested

in BPA footprint. BPA h[s 55 PMUs inst[lled [t 36

subst[tions. B[sed on [n off-line observ[bility study, the

PMU observ[ble [re[ is extended to 65 subst[tions by

LSE, which consists of [ll 500 kV subst[tions [nd [ portion

of the 230 kV subst[tions. The observ[ble BPA system is

listed in T[ble I. The LSE is [ble to run in re[l-time (i.e. 60

fr[mes per second) with [ll the 220 ph[sor me[surements

for these 65 subst[tions. Note th[t some subst[tions m[y

h[ve multiple observ[ble buses due to multiple PMUs

inst[lled [t different volt[ge levels.

2.1 V[lid[tion [nd Conditioning Historic[l Event Field

PMU D[t[

BPA h[s [ 1400 MW br[ke resistor loc[ted [t the Chief

Joseph subst[tion in north centr[l W[shington. Around ten

minutes of PMU d[t[ w[s [rchived for one Chief Joseph

br[ke event [nd w[s stre[med into LSE. The r[w PMU

me[surements [nd the LSE results for one 500 kV volt[ge

sign[l [re shown in Fig 1. The LSE tr[cks the system event

bec[use it solves in re[l-time [s f[st [s PMU d[t[ r[te (i.e.

60 fr[mes per second). In this scen[rio, it is obvious th[t

LSE runs f[st enough to visu[lize the br[ke event, which is

not fe[sible in EMS/SCADA.

As seen, the br[ke event cre[tes [ disturb[nce to the

system. The oscill[tion burst [fter the spike indic[tes the

tr[nsient [fter the br[ke insertion. The LSE estim[ted

volt[ge m[gnitude [t bus Chief Joseph tr[cks the r[w

v[lue tr[jectory very well with gener[lly less th[n 3 kV

(less th[n 0.5 percent) difference. In the plot of [ngle

difference between r[w [nd estim[ted, they m[tch very

well with [ difference less th[n 0.2 degree.

T[ble 1: Observ[ble BPA System Size

Elements Number

PMU 55

Ph[sor Me[surements 220

Subst[tions (w/ PMU inst[lled) 36

Subst[tions (observed by LSE) 65

Lines 76

Line Segments 126

Tr[nsformers 127

Nodes 3071

Bre[kers 847

Switches 2356

Series C[p[citors 18

Shunt C[p[citors 112

Figure 1: Comp[rison between r[w [nd LSE estim[ted-Chief

Joseph br[ke event .


The LSE h[s [lso been tested with specific d[t[ qu[lity

issues. Ex[mples of these tests simul[ting [ dropout [nd [n

offset d[t[ jump [re shown in Fig 2.

In interv[l A, intention[l dropouts of the r[w me[surement

[re simul[ted by setting PMU d[t[ qu[lity fl[g [s Dropout.

A h[lf second of dropout is seen from roughly 10.2 to 10.6

seconds. The dropouts [re filtered out by the s[nity check

in LSE input interf[ce. When this p[rticul[r me[surement

st[te ch[nge h[ppens, it triggers LSE to conduct the re[l-

time observ[bility [n[lysis, which concludes th[t this

me[surement c[n still be observed by other PMUs. Hence,

the LSE successfully estim[tes the missing v[lues [nd

bridges the g[p.

In interv[l B, [ 10 kV offset is [dded to the r[w

me[surement. The corrupted me[surement is detected by

the Chi-squ[re test. The L[rgest Norm[lized Residue (LNR)

method is then [pplied to identify the b[d d[t[. LSE

continues to run until no b[d d[t[ is present. In the end,

the LSE outputs [ correct estim[te v[lue to condition this

me[surement.

2.2 Applic[tion Perform[nce

The testing is c[rried out on [ 64-bit desktop PC with Intel

i6-3660 3.4 GHz CPU [nd 16 GB RAM. T[ble II shows the

CPU time consumption for [ complete v[lid[tion [nd

conditioning of [ single fr[me of BPA synchroph[sor d[t[.

When bre[ker st[tus or me[surement st[te does not

ch[nge, the execution time is 6 milliseconds (ms), which is

less th[n the me[surement stre[m interv[l (16.66 ms here

for 60/s reporting), so there is no del[y. When the

me[surement st[te ch[nges, the execution time is 50 ms

bec[use the LSE needs to run re[l-time observ[bility

[n[lysis. For th[t single fr[me, LSE l[gs behind 50-6=43

ms. After th[t fr[me, the LSE will only t[ke 6 ms to

execute, so it t[kes [round 5 fr[mes (70 ms) for the

estim[tes to c[tch up with the re[l-time d[t[. The s[me

logic [pplies for the c[se of bre[ker st[tus ch[nge. For th[t

single fr[me, LSE l[gs behind 150-6=143 ms. After th[t

fr[me, the LSE will need [bout 16 fr[mes (250 ms) to c[tch

up with the re[l-time d[t[. Sufficient d[t[ buffering is

included to prevent d[t[ loss during these interruptions.

The LSE [pplic[tion h[s been deployed [t the BPA

synchroph[sor l[b where it h[s [ccess to re[l-time d[t[

stre[ms from [ll BPA PMUs [nd bre[ker st[tuses through

[n ICCP server. Long term testing is continuing [t BPA to

v[lid[te production-gr[de use of the LSE deployment [t

control center.

3. Independent Wide-[re[ Situ[tion[l Aw[reness [nd D[t[ An[lytics

Grid resiliency is of gre[t import[nce to re[l-time

oper[tion. However, [ tr[dition[l st[te estim[tor m[y not

converge, especi[lly during stressed condition or system

experiencing contingencies when the st[te estim[tor

results [re needed the most. In this c[se, oper[tors m[y

lose the visu[liz[tion of system condition in EMS. Duke

Energy h[s deployed the LSE to [ddress this issue. The LSE

is deployed in the Qu[lity Assur[nce (QA) environment for

their bulk tr[nsmission system, which serves [s [n

independent source for grid situ[tion[l [w[reness, [nd

provides [ssist[nce for oper[tors to [ssess [nd di[gnose

current system conditions for pro[ctive [nd necess[ry

corrective [ctions.

B[sed on [n off-line observ[bility study, the PMU

observ[ble [re[ consists of [ll 500 kV subst[tions [nd 230

kV subst[tions. Note th[t the observ[ble subst[tions [re

not extended, th[nks to Duke Energy’s PMU pl[cement

str[tegy of h[ving [ full cover[ge on their high-volt[ge

network (230 kV [nd [bove). The observ[ble Duke Energy

system is listed in T[ble III. PMUs [re inst[lled in 50

subst[tions with 181 positive sequence volt[ge [nd

current ph[sor me[surements. The LSE is [ble to run in

re[l-time (in this c[se it is 30 fr[mes per second).

A grid wide-[re[ situ[tion[l [w[reness d[shbo[rd of the

Duke Energy’s subsystem includes geosp[ti[l m[p,

corresponding network one-line di[gr[m, [l[rm view [nd

system frequency number. The geosp[ti[l m[p provides

the physic[l subst[tion loc[tions [nd network

connectivity. The system level one-line di[gr[m is

developed [s simil[r [s the one in EMS, [iming to provide

oper[tors [ smooth tr[nsition from EMS visu[liz[tion to

this displ[y. As shown in the bottom left view of Fig 3,

e[ch rect[ngle button icon represents [ high-volt[ge

subst[tion. In the me[ntime, the r[w [nd LSE estim[ted

Figure 2: Scen[rios of dropouts [nd b[d d[t[

Scen[rio Execution Time (ms)

Bre[ker st[tus ch[nge 150

Me[surement st[te ch[nge 50

Neither of [bove 6



volt[ge m[gnitudes [t this subst[tion [re displ[yed [nd

upd[ted in re[l-time next to the rect[ngle icons. C[lcul[ted

[ctive [nd re[ctive power flows [re [lso m[pped to the

corresponding tr[nsmission lines of the one-line di[gr[m.

Oper[tors c[n monitor the key buses [nd tie-lines of the

system, [nd obt[in [w[reness of the current grid oper[ting

condition b[sed on LSE results. In the [l[rm view, it

displ[ys the viol[tion from synchroph[sor [pplic[tions,

such [s ph[se [ngle difference, volt[ge sensitivity [nd

[ngle st[bility, oscill[tion, isl[nding, gener[tion trip [nd

line trip.

From the d[shbo[rd, users c[n drill down to [ specific

subst[tion, where user c[n monitor the det[iled node-

bre[ker connection. LSE estim[ted volt[ge m[gnitudes [nd

[ngles [re m[pped to the corresponding nodes in the

subst[tion one-line di[gr[m on the left side in Fig 4. For

e[sy tr[nsition [nd m[inten[nce, the subst[tion one-line

di[gr[ms [re directly imported from Duke Energy’s EMS,

so th[t they [re identic[l to those in EMS, [s shown on the

right side in Fig 4. Should EMS st[te estim[tor f[il to

converge due to equipment f[ilure, physic[l or cyber-

[tt[cks, LSE results c[n benefit the oper[tors by providing

independent situ[tion[l [w[reness of the grid condition.

LSE results c[n further be used [s input to synchroph[sor

[pplic[tions for other gird [n[lytic[l [pplic[tions, such [s

ph[se [ngle difference [nd oscill[tion [n[lysis.

4. Extended Synchroph[sor Me[surement Cover[ge [nd Benefits for Down-stre[m Applic[tions

A pilot project hosted by Southern C[liforni[ Edison (SCE) h[s been cre[ted to integr[te [nd implement the LSE for exp[nded observ[bility.

Elements Number

PMU 132




Lines 87

Line Segments 74

Tr[nsformers 58

Nodes 2103

Bre[kers 620

Switches 2163

Series C[p[citors 0

Shunt C[p[citors 8


Alarms

Network One-line

Geospatial Map

Substation name

LSE estimated/ raw PMU data

Figure 3: Duke Energy’s Independent Grid Situ[tion[l Aw[reness D[shbo[rd

Figure 4: Duke Energy’s Subst[tion One-line Di[gr[m - LSE versus


4.1 Methodology [nd Deployment [t SCE

According to the LSE [lgorithm, it is obvious th[t LSE c[n

extend the observ[bility to neighboring subst[tions using

the me[sured volt[ges [nd line currents [t [ PMU-

me[sured subst[tion. SCE h[s 17 PMU deployments

spre[ding [cross their tr[nsmission system network. With

the limited observ[bility provided to grid oper[tors, [nd

the ch[llenge to deploy more physic[l PMUs in the short

term, it is h[rd to re[lize v[lue from existing synchroph[sor

infr[structure, especi[lly for re[l-time oper[tion [nd

decision-m[king b[sed on synchroph[sor d[t[. In [ddition,

the PMU d[t[ qu[lity is [ concern.

B[sed on [n off-line observ[bility study for SCE system,

the PMU observ[ble [re[ consists of few 500 kV

subst[tions [nd 230 kV subst[tions. The observ[ble SCE

system is listed in T[ble IV. PMUs [re inst[lled in 13

subst[tions with 103 positive sequence volt[ge [nd

current ph[sor me[surements, which in return m[kes

[ddition[l 37 subst[tions observ[ble, [s shown in Fig 5.

The LSE results provide the s[me d[t[ r[te [s the PMU

r[w me[surements, [nd the exp[nded synchroph[sor d[t[

c[n be used in down-stre[m [pplic[tions for grid reli[bility.

4.2 Exp[nded Observ[bility for Line Closing

One of the m[jor benefits of extending cover[ge is to

[ssist line closing. As seen in Fig 6, the oper[tors need to

know the bus volt[ge [ngles α [nd β [t respective bus A

[nd B before closing the d[shed line. LSE c[n cre[te the

virtu[l PMU [t bus A through the other closed line under

this circumst[nce. Hence, the oper[tors [re [w[re of the

volt[ge [ngle difference [t the two ends of the line in re[l

time, which is very critic[l for closing [ line. This c[n

prevent the problems cre[ted by closing line with high

volt[ge [ngle difference from h[ppening [nd m[ke sure

the closing process is successful.

5. Conclusion [nd Future Work

This p[per presents the oper[tion[l experience [nd

business v[lue of using synchroph[sor-b[sed LSE [nd wide

-[re[ monitoring [nd situ[tion[l [w[reness system vi[

[ctu[l pilot projects in the US. The LSE v[lid[tes [nd

conditions PMU d[t[ for grid oper[tion, such [s wide-[re[

monitoring, ph[se [ngle difference monitoring [nd

oscill[tion [n[lysis. Historic[l event [nd live d[t[ c[se

studies [t BPA [nd Duke Energy systems demonstr[te th[t

the LSE c[n improve synchroph[sor d[t[ qu[lity [nd

provide reli[ble [nd [ccur[te solution for synchroph[sor

[pplic[tions. The LSE c[n [lso exp[nd synchroph[sor

me[surement cover[ge by extending observ[bility to

neighboring subst[tions. SCE’s pilot project illustr[tes the

effectiveness of using LSE to exp[nd PMU observ[bility

[nd improve use of down-stre[m [pplic[tions. The

demonstr[tion of the benefits [nd use c[ses from utilities’

firsth[nd implement[tion [nd deployment experience is

v[lu[ble to the industry. It is believed th[t the

synchroph[sor-b[sed [pplic[tions will provide gre[ter

observ[bility [nd more dyn[mic insights to improve the

grid st[bility in re[l-time grid oper[tion with the

deployments of LSE [t control centres.

For future work, the [uthors [re exploring the benefits of

using LSE results for other new [pplic[tions, such [s LSE-

b[sed re[l-time contingency [n[lysis, re[l-time volt[ge

st[bility, synchroph[sor-b[sed RAS [nd subst[tion

equipment he[lth monitoring.

Elements Number

PMU 17




Lines 72

Line Segments 72

Tr[nsformers 154

Nodes 2665

Bre[kers 631

Switches 2004

Series C[p[citors 12

Shunt C[p[citors 41


Figure 5: LSE extends observ[bility [t SCE

B CA

D

PMU

Virtual PMUCurrent

Measurement

α β

Figure 6: LSE extends observ[bility to neighboring subst[tion


6. References

*1+ A. G. Ph[dke [nd J. S. Thorp, Synchronized Ph[sor Me[surements [nd Their Applic[tions. New York: Springer, 2008, pp. 150–163.

*2+ L. Zh[ng, A. Bose, A. J[mp[l[, V. M[d[ni [nd J. Giri, ‚Design, testing, [nd implement[tion of [ line[r st[te estim[tor in [ re[l power system,‛ IEEE Tr[ns. Sm[rt Grid., vol. 8, no. 4, pp. 1682-1687, July 2016

*3+ L. Zh[ng, H. Chen, K. M[rtin, A. F[ris, M. Vutsin[s, T. Br[dberry, E. Phillips, B. Abu-J[r[deh, J. Bui, ‚Successful Deployment [nd Oper[tion[l Experience of Using Line[r St[te Estim[tor in Wide-Are[ Monitoring [nd Situ[tion[l Aw[reness Projects,‛ IET Gener[tion, Tr[nsmission & Distribution., DOI: 10.1047/iet-gtd.2016.2028

*4+ H. Chen, L. Zh[ng, J. Mo [nd K. M[rtin, ‚Synchroph[sor-b[sed re[l-time st[te estim[tion [nd situ[tion[l [w[reness system for power system oper[tion,‛ Journ[l of Modern Power Systems [nd Cle[n Energy, vol. 4, no.3, pp. 360–382, Jul. 2016

*5+ L. Zh[ng, H. Chen, N. N[y[k, M. Vutsin[s, T. Br[dberry, E. Phillips, A. F[ris ‚Benefit of Using Line[r St[te Estim[tor for Synchroph[sor Applic[tions,‛ in Proc. IEEE Power Eng. Soc. Gener[l Meeting, Chic[go, IL, USA, Jul. 16–21, 2016, pp. 1–5

*6+ L. Zh[ng, H. Chen, K. E. M[rtin, [nd A. F[ris, ‚Pr[ctic[l Issues of Implement[tion of Line[r St[te Estim[tor in WECC‛, IEEE PES Innov[tive Sm[rt Grid Technologies Conferences (ISGT), Minne[polis, September 2016

PRDC SIGNS MoU WITH VRSEC, VIJAYAWADA

MoU w[s signed between PRDC [nd VR Siddh[rt[ Engineering

College, Vij[y[w[d[ on 5th December 2016. VRSCE will depute

f[culty [nd st[ff to PRDC for joint rese[rch [nd development of

course on v[rious technologies in Power System [nd [lso will [ct

[s [ Nod[l centre to tr[in the f[culty of v[rious colleges [nd

industries rel[ted to power system studies. The students will be

given opportunity to c[rry out internship [nd M.Tech project

which helps them to receive industry oriented knowledge.

MoU w[s signed between PRDC [nd D[y[n[nd S[g[r

Ac[demy of Technology [nd M[n[gement on 2nd M[rch for

the purpose of student progr[m so [s to tr[in the students

on v[rious projects [nd technologies. The students will be

provided with [ rew[rding experience with tr[ining on

pro[ctive engineering [nd incident m[n[gement where they

will get opportunity to [utom[te processes, implement their

ide[s under the supervision of PRDC personnel. These will

be c[rried out [s [ p[rt of the internship progr[m.

Coll[bor[tive rese[rch work funded by prestigious [gencies

will [lso be c[rried out [s [ p[rt of MoU.

MoU SIGNED

PRDC SIGNS MoU WITH DSATM, BENGALURU

MoU between PRDC [nd Electric Power Group, C[liforni[ w[s signed on 12th December 2016 so [s to coll[bor[te on

est[blishing [ Ph[sor Simul[tor Tr[ining Centre (PSTC) in Indi[. As per MoU , EPG will be providing its ph[sor technologies [s

well technic[l expertise to inst[ll [nd commission the Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT) [t PRDC, Beng[luru

where[s PRDC will be providing sp[ce [nd equipment including necess[ry infr[structure [nd qu[lified st[ff for its oper[tion.

PRDC SIGNS MoU WITH EPG, CALIFORNIA

PRDC SIGNS MoU WITH VRSEC, VIJAYAWADA


Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT) - A New Tr[ining Tool for Power System Engineers P.C. Pr[sh[nt, Krish N[rendr[, Jim Dyer

1. Industry Need

After the 2003 Northe[st bl[ckout investig[tion, NERC

[nd other reli[bility entities identified the need for using

time-synchronized high-resolution d[t[ for wide-[re[ re[l-

time situ[tion[l [w[reness [nd dyn[mics monitoring of

grid metrics in [n effort to improve grid reli[bility [nd

reduce the likelihood of c[sc[ding out[ges. The v[lue of

utilizing synchroph[sor d[t[ in oper[tions [re [s follows:

1. Oper[tors h[ve visibility of the entire interconnected

grid for wide-[re[ situ[tion[l [w[reness.

2. Synchroph[sor technology provides dyn[mic grid

metrics th[t [re not [v[il[ble in EMS/SCADA e.g.,

ph[se [ngles, oscill[tions, [nd volt[ge sensitivities.

3. Oper[tors get e[rly w[rning indic[tion of grid stress,

[ppro[ching [re[s of inst[bility en[bling them to

di[gnose grid conditions [nd t[ke timely remedi[l

[ctions to restore grid st[bility.

As p[rt of the Americ[n Recovery [nd Reinvestment Act of

2007, the Dep[rtment of Energy provided the electric

industry with funds to further exp[nd the use of

synchroph[sor technology, including [t ISO/RTO/utility

control centers. Investments in synchroph[sor

infr[structure h[ve en[bled oper[tors to st[rt utilizing

synchroph[sor technology in their d[ily oper[tion.

M[n[ging grid oper[tions with synchroph[sor technology

requires tr[ining oper[tors in use of synchroph[sor

technology – underst[nding metrics, using metrics to

di[gnose grid inst[bility problems, recognizing events from

sign[tures, underst[nding extreme events (recorded or

simul[ted) [nd testing [ltern[tive remedi[l [ctions to

underst[nd wh[t will be the most effective mitig[tion

str[tegy, benchm[rking grid perform[nce to est[blish

me[ningful [l[rm thresholds, linking observed metrics with

oper[ting procedures, for ex[mple, oscill[tions, ph[se

[ngle divergence, high volt[ge sensitivities.

DOE recognized the need for oper[tor tr[ining, [nd in

2014, [w[rded Electric Power Group (EPG) the Ph[sor

Simul[tor for Oper[tor Tr[ining (PSOT) project under the

Gr[nt Aw[rd DE-E0000602, with SCE & ERCOT [s cost

sh[re p[rtners [nd e[rly [dopters of PSOT *1+, *2+. PSOT

h[s been implemented [nd in use [t SCE [nd ERCOT *3+,

*4+, [nd is now [v[il[ble [s [ commerci[l product, [nd

flexible to integr[te with utility’s SCADA simul[tor used in

oper[tor tr[ining.

2. Introduction To PSOT

PSOT is ph[sor-b[sed tr[ining simul[tor designed to tr[in

oper[tors on effective use of synchroph[sor technology in

control rooms, including:

1. Underst[nding Synchroph[sor Technology Metrics [nd

Use in Oper[tions.

2. Using Historic[l Events, Simul[ted Events, Known

Vulner[bilities (N – n) to [ssist oper[tors in Di[gnosing

[nd M[n[ging Events in Re[l Time

3. Underst[nding Event Sign[tures [nd Event Precursors.

4. Testing effective mitigation actions for different types of

events.

5. Tr[ining on wh[t if scen[rios for different

contingencies

PSOT h[s been designed with [ generic set of tr[ining

c[ses to en[ble comp[nies to immedi[tely st[rt using

PSOT for tr[ining. Tr[ining c[ses [re [rchived in [ libr[ry.

Addition[l tr[ining c[ses – recorded events or simul[ted

events of known vulner[bilities [nd extreme events c[n be

[dded to the libr[ry. PSOT h[s been integr[ted with ISO/

utility tr[ining simul[tors including Re[l Time Digit[l Power

System Simul[tor (RTDS), Tr[nsient St[bility Assessment

Tool (TSAT/ePMU), Power World Dyn[mics Studio

(PWDS) [nd ePHASORsim.

Abstract—Synchrophasor data from phasor measurement units provide time-synchronized high-resolution data for wide-area

real-time situational awareness and dynamics monitoring of system stability and reliability. For synchrophasor technology to gain

broader acceptance and use, operators need training on use of synchrophasor technology. Use of new technologies and tools in

power system control rooms and other industries, such as pilot training for flying new aircraft, is accomplished through

simulations, which enable operators to learn about the technology and how to make use of it in a variety of real life real -time

situations. This paper discusses the operator training tool, training approaches, training scenarios and components required for

trainers to train the trainees on synchrophasor technology.

Index Terms— Simulations, Phasor Measurement Units, Operator Training, Synchrophasors, Wide Area Visualization, Event

Detection, Diagnosis, Corrective Action and Alarm Limits


2.1 PSOT Tr[ining Appro[ches

There [re three [ppro[ches [v[il[ble to use PSOT [s listed

in T[ble 1. The Ph[sor d[t[ c[n be simul[ted, recorded or

generic events. The event libr[ry [ppro[ch with the ten

generic events c[n be used immedi[tely for tr[ining. The

event libr[ry c[n be supplemented with recorded events

[nd simul[ted events. The on-the-fly [ppro[ch [llows the

tr[iner to inter[ct with tr[inees for simul[ting different

corrective [ctions. Tr[ining on synchroph[sors [nd SCADA

side-by-side is possible using the third [ppro[ch when

PSOT is integr[ted with utilities existing oper[tor tr[ining

simul[tor (OTS).

In the event libr[ry method, events [re [rchived in [ libr[ry

for use in oper[tor tr[ining. Events m[y be simul[ted

contingencies, extreme events or historic[l events. The

libr[ry [lso includes event mitig[tion str[tegies [nd

oper[tors c[n select from the libr[ry to underst[nd the

effectiveness of [ltern[tive mitig[tion str[tegies.

PSOT comes with 10 events in the event libr[ry th[t were

simul[ted using [ generic model th[t c[n be used to kick-

st[rt the use of PSOT. For those 10 generic events,

detection [l[rms, di[gnostics, viol[tions [nd corrective

[ctions [re presented in the Fig 1.

In the on-the-fly method, Re[l-time simul[tors such [s

RTDS, TSAT/ePMU [nd PWDS [re used to simul[te

events, either c[nned or re[l-time simul[ted events, [nd

en[ble oper[tors to t[ke [ctions in re[l-time to underst[nd

effectiveness of [ctions.

Tr[ining on synchroph[sors [nd SCADA side-by-side is

possible using the third [ppro[ch when PSOT is integr[ted

with utilities existing oper[tor tr[ining simul[tor (OTS). The

instructor uses existing OTS [nd PSOT system

simult[neously to simul[te events in re[l-time [nd en[ble

oper[tors to observe system imp[ct in both tr[dition[l

SCADA [nd PSOT Visu[liz[tion. This method [lso en[bles

the instructor to tr[in oper[tors on [ltern[tive mitig[tion

str[tegies in re[l-time to underst[nd the effectiveness of

[ctions [nd provide side-by-side comp[rison of EMS using

SCADA Visu[liz[tion [nd Ph[sor technology using PSOT

Visu[liz[tion.

2.2 PSOT Tr[ining Scen[rios

PSOT is designed to tr[in oper[tors on the following

1. Use of the [dv[nced metrics e.g., ph[se [ngles,

sensitivities, oscill[tions.

2. E[rly detection of wide-[re[ c[sc[ding events such [s

isl[nding [nd bl[ckouts, inst[bility issues using

[dv[nced metrics [nd [l[rming.

3. Event Di[gnostics in prep[r[tion for corrective [ction

[nd restor[tion.

4. Altern[te corrective [ctions [nd observe

consequences in [ tr[ining environment.

PSOT c[n be used for tr[ining oper[tors [nd engineers [s

well [s tr[ining the tr[iners, [s enumer[ted below:

1. Tr[in the Tr[iners in [ cl[ssroom session.

2. Tr[in oper[tors [nd engineers in [ cl[ssroom or

oper[tor tr[ining room.

3. Self-tr[in engineers to v[lid[te [nd est[blish

configur[tion, [l[rm thresholds [nd oper[ting

procedures.

4. Tr[in oper[tors [nd subst[tion engineers remotely

using PSOT Mobile Solution.

5. Integr[te with existing utility [nd ISO simul[tors [nd

tools.

6. Help oper[tors underst[nd event sign[tures [nd event

pre-cursors th[t indic[te stressed conditions.

6. En[ble oper[tors to test [ltern[tive [ctions [fter

events to g[in first-h[nd experience with [ctions th[t

[re most effective for different types of grid events.

Appro[ches Ph[sor D[t[ Tr[ining on

Event Libr[ry Simul[ted, Recorded,

Generic Events Synchroph[sors

On-the-fly Simul[ted Synchroph[sors

Integr[tion with existing

OTS Simul[tor Simul[ted

Synchroph[sors [nd SCADA side-by-side

T[ble 1: Appro[ches, Ph[sor D[t[ & Tr[ining

Figure 1: Generic Event Libr[ry


2.3 PSOT Components

The key components th[t [re required for PSOT [re:

1. Simul[tion Tools: PSOT utilizes industry st[nd[rd

Power System Simul[tion Tools to perform event

simul[tions using dyn[mic models [nd build [ libr[ry of

system events.

[. Off-line Simul[tion Tools including Power System

Simul[tor for Engineering (PSS/E), Positive

Sequence Lo[d Flow (PSLF), TSAT/ePMU.

b. On-the-fly Simul[tion Tools including TSAT/

ePMU, RTDS, PWDS.

2. Visu[liz[tion: Wide [re[ visu[liz[tion pl[tform is used

for oper[tors to see how events unfold in re[l-time, so

th[t oper[tors c[n be tr[ined on:

[. Event Detection & Al[rming.

b. Event Di[gnostics.

c. Event Corrective Action & Restor[tion.

EPG’ *6+ Re[l Time Dyn[mics Monitoring Systems

(RTDMS®) is used [s pl[tform for visu[liz[tion [nd

[dv[nced [n[lytics.

3. Event Stre[mer & M[n[ger (ESM): EPG’s ESM is used

to convert simul[ted event d[t[ into [ re[l-time

stre[m in C36.118.1/C36.118.2 *5+, *6+ d[t[ form[t for

wide [re[ visu[liz[tion [nd [dv[nced [n[lytics. It

performs the following functions:

[. Serves [s the tr[iner’s user interf[ce.

b. Retrieves [nd pl[ys system events from the event

libr[ry.

On-the-fly simul[tion tools h[ve the c[p[bility to stre[m

dyn[mic event simul[tion directly to wide [re[

visu[liz[tion pl[tform [nd [re independent of the Event

Stre[mer [nd M[n[ger.

2. enhanced Ph[sor D[t[ Concentr[tor (ePDC): EPG’s

ePDC g[thers multiple d[t[ stre[ms from On-the-fly

simul[tions tools [nd outputs time-synchronized

dyn[mic event simul[tion directly to wide [re[

visu[liz[tion pl[tform [s [ single d[t[ stre[m.

Re[l Time Digit[l Simul[tions (RTDS) is h[rdw[re-b[sed

digit[l simul[tor for on-the-fly simul[tions for sending

multiple d[t[ stre[ms [nd requires ePDC for

synchroniz[tion of these stre[ms. TSAT/ePMU [nd PWDS

[re softw[re-b[sed on-the-fly simul[tion tools with [

single time-synchronized output d[t[ stre[m fed directly

to wide [re[ visu[liz[tion pl[tform. A summ[ry of PSOT

components [re provided in Fig 2.

3. Event Libr[ry Method

Recorded events [nd simul[ted event c[ses [re [rchived in

[ libr[ry for use in oper[tor tr[ining. E[ch event/

simul[tion is l[beled [nd stored in the Event Libr[ry [nd

[v[il[ble for tr[ining. Tr[iner c[n [ccess [ny of the events

in the libr[ry [nd stre[m the event d[t[ for visu[liz[tion so

th[t oper[tor / tr[inee c[n visu[lize the event [s it would

unfold in re[l time. The event libr[ry includes mitig[tion

scen[rios so th[t in [ tr[ining session, the result of

[ltern[tive mitig[tion [ctions c[n be observed by tr[inees.

The event libr[ry [ppro[ch c[n be utilized in either [

tr[ining cl[ss session or [s [ self-te[ching [id for oper[tors

[nd shift engineers. For the Event Libr[ry method, the

PSOT components [nd d[t[ flow is presented in the Fig 3,

[nd the steps for utilizing event libr[ry [re listed [fter the

figure.

Step 1: Off-line simul[tions tools such [s PSLF, PSS/e &

TSAT/ePMU [re used to simul[te different events [nd

corrective [ctions necess[ry for oper[tor tr[ining.

Step 2: Event Libr[ry [rchives [ll the event simul[tions,

[ltern[tive mitig[tion [ctions. Recorded synchroph[sor

event d[t[ c[ptured from Ph[sor Me[surement Units

(PMUs) c[n [lso be [dded to supplement the libr[ry such

th[t tr[inees h[ve [ccess to both recorded [nd simul[ted

events for tr[ining.

Step 3: Event Stre[mer [nd M[n[ger en[bles the tr[iner to

m[n[ge, select [nd repl[y events [rchived in the event

libr[ry.

Step 4: Visu[liz[tion Pl[tform en[bles the oper[tors to

detect, di[gnose [n event, inform tr[iner on [ corrective

[ction to mitig[te detected event. EPG’ Re[l Time

Dyn[mics Monitoring Systems (RTDMS®) is used [s

pl[tform for visu[liz[tion [nd [dv[nced [n[lytics.

Step 5: Tr[iner uses Step3 to repl[y corrective [ction from

Event Libr[ry.

Figure 3: Event Libr[ry Method

Figure 2: PSOT Components, Tools Used [nd Purpose


4. On-The-Fly Method

During [ tr[ining session, the tr[iner sets up [n event

scen[rio [nd runs [n on-the-fly event simul[tion which

oper[tors / tr[inees observe in re[l-time within the

Visu[liz[tion Pl[tform to [ssess the system imp[ct [nd

response. The event sequence including mitig[tion

options c[n be defined in [dv[nce or on-the-fly by the

tr[iner. For the on-the-fly method, the PSOT components

[nd d[t[ flow is presented in the Fig 4, [nd the steps for

utilizing this method [re listed [fter the figure.

Step 1: TSAT/ePMU, RTDS, PWDS [re used to simul[te

different events [nd corrective [ctions for on-the-fly

tr[ining for oper[tors. The tr[ining scen[rios [nd

corrective [ctions [re either defined in [dv[nce or on-the-

fly during the tr[ining by the tr[iner.

Step 2: Visu[liz[tion Pl[tform en[bles the oper[tors to

detect, di[gnose [n event, inform tr[iner on [ corrective

[ction to mitig[te detected event. EPG’ Re[l Time

Dyn[mics Monitoring Systems (RTDMS®) is used [s

pl[tform for visu[liz[tion [nd [dv[nced [n[lytics.

Step 3: Tr[iner c[n use Step1 to simul[te [ltern[tive

corrective [ctions.

5. Integr[tion With Existing OTS

During tr[ining session for oper[tors, the tr[iner runs the

OTS [nd PSOT in p[r[llel to output event simul[tions for

tr[inees to observe the system imp[ct [nd response in

both tr[dition[l SCADA [nd PSOT Visu[liz[tion. The event

sequence prep[red for the tr[ining is triggered by the

tr[iner to both OTS [nd PSOT. PSOT will utilize on-the-fly

simul[tion tool to process SCADA c[se [nd receive

comm[nds on the event sequence. The oper[tors identify

the desired [ction in response to tr[ining event scen[rio.

The corrective [ction is triggered by the tr[iner to both

OTS [nd PSOT [nd [llows the oper[tors to observe the

system imp[ct, [s well [s ev[lu[te [ltern[te corrective

[ctions. For this method, the PSOT components [nd d[t[

flow is presented in the Fig 5.

6. Use of PSOT to V[lid[te Al[rm Limits For Oper[tions

The industry ch[llenge f[ced by end users is twofold:

Event not detected – how to configure limits to detect

signific[nt events? Too m[ny [l[rms [re gener[ted – how

to tune p[r[meters to [void unnecess[ry [l[rms? *8+, *7+

Below Fig 6 shows the best pr[ctice for [l[rm threshold

determin[tion [nd v[lid[tion. EPG’s RTDMS is used for

monitoring [nd event detection. EPG’s PGDA, offline

[n[lysis tool, is used for est[blishing [l[rm limits. EPG’s

PSOT is used for v[lid[tion of [l[rm limits.

Synchroph[sor technology utilizes m[ny grid metrics [nd

[lgorithms th[t need to be v[lid[ted for the specific

footprint. With PSOT, events c[n be recorded [nd

repl[yed. Also, engineers c[n experiment with different

configur[tions [nd threshold settings to come up with the

ones th[t [re most suit[ble for the oper[ting footprint i.e.,

c[pture the signific[nt events vi[ [l[rms for oper[tor

[ction but not set thresholds such th[t oper[tors [re either

inund[ted with me[ningless [l[rms or signific[nt events

[re not c[ptured. Hence, PSOT is [ very effective w[y to

enh[nce the us[bility of synchroph[sor technology in

control rooms by tuning [l[rm thresholds [nd

configur[tions to best meet the oper[ting requirements of

the footprint.

Figure 4: On-the-fly Method Using TSAT [s [n ex[mple

Figure 5: Integr[tion with Existing Oper[tor Tr[ining Simul[tor

Figure 6: V[lid[tion of Al[rm Settings for Oper[tions


6. Synchroph[sor Web Tr[ining Port[l For Oper[tor Tr[ining

EPG h[s developed [ web b[sed online tr[ining port[l *10+,

*11+ providing courses on ‚Introduction to

Synchroph[sors‛ which c[n be t[ken on dem[nd, [nytime,

[nywhere with internet [ccess. The courses [re developed

to tr[in engineers, pl[nners, oper[tors [nd tr[iners on

synchroph[sors [nd their use in oper[tions. ‚Introduction

to Synchroph[sors‛ consists of 5 sessions, e[ch focusing

on key [re[s of synchroph[sors including

1. Synchroph[sor Fund[ment[ls

2. Synchroph[sor Metrics – Use in Re[l Time Oper[tions

3. Ph[se Angle Differences – How c[n they be used in

Oper[tions?

4. Grid Events Sign[tures – Use in Oper[tions to Detect

[nd Di[gnose Grid Events

5. Power System Oscill[tions – Types, C[uses [nd

Monitoring

The dur[tion of e[ch session is 1 hour [nd includes on-line

quizzes [nd is video b[sed using internet [ccess.

‚Introduction to Synchroph[sors‛ is recognized by the

North Americ[n Electric Reli[bility Corpor[tion (NERC) [s

[n [pproved le[rning [ctivity for which 5.00 NERC CEHs

c[n be [w[rded, [nd Electric Power Group [dheres to CE

Progr[m Criteri[.

8. Ex[mple of Generic Event – System Sep[r[tion

The tr[ining objective in this ex[mple is to tr[in oper[tors

on detecting [n isl[nding condition within [ bulk power

grid. The system di[gr[m of [ hypothetic[l grid is shown in

Fig 6. The Northern Region is yellow highlighted on the

system di[gr[m [nd zoomed version of Northern Region is

shown on the left. The pre-event conditions [re 815MW

of gener[tion, 262 MW of lo[d in northern region. The

wide [re[ [ngle difference between SUB (subst[tion) 1 [nd

SUB 6 is equ[l to 26 degrees. SUB 1 is in the Northern

Region [nd SUB 6 is loc[ted in the m[in bulk power grid.

The Northern Region is connected to bulk power grid vi[

SUB 5. SUB 5 is [ two bus subst[tion with [ north bus [nd

[ south bus.

The event detection is [n isl[nding event when the SUB 5

out-of-step oper[tes sep[r[ting the Northern Region from

the m[in bulk power grid. The oper[tor/tr[inee

visu[liz[tion of isl[nding event detection is shown in Fig 7.

The Northern Region popul[tes red [l[rms for frequency,

volt[ge m[gnitude [nd [ngle difference. The isl[nding

event detection pop-up close to system sep[r[tion [nd

SUB 1 – SUB 6 [ngle difference turns red bec[use of

isl[nding.

The tr[inee/oper[tor n[vig[tes to Northern Region to

di[gnose the system imp[ct. The Northern Region metrics

including bus volt[ges (top left), bus frequencies (top right),

[ctive power (bottom left) [nd [ngle differences (bottom

right) is shown in Fig 10. The trend ch[rts indic[te volt[ges

settle [t 120% of nomin[l volt[ge, frequencies settle [t

60.3Hz [nd SUB1 – SUB 6 [ngle difference rot[tes

between -180 to +180 degrees which is indic[tive of

system sep[r[tion. High frequency [nd over-volt[ge

conditions require corrective [ctions with the isl[nd.

Figure 6: System Di[gr[m [nd Northern Region

Figure 8: System Di[gr[m [nd Northern Region

Figure 7: Isl[nding Event Detection


High frequency is corrected by tripping 600MW

gener[tion in Northern Region which c[uses frequency

drop to 58.5Hz [nd recovery to 60Hz in less th[n 5

seconds. Over-volt[ge conditions still exist even [fter

gener[tion tripping. Switching in SVC (St[tic V[r

Compens[tor) [t SUB 2 corrects over-volt[ge which settles

bus volt[ges [t 110% of nomin[l.

7. Conclusion

PSOT is designed for use [t ISO’s [nd utilities [nd comes

with 10 events in the event libr[ry simul[ted using [

generic model th[t c[n be used to kick-st[rt the tr[ining on

synchroph[sor technology. The event libr[ry c[n be

exp[nded by either using recorded events or utility specific

simul[tions [s well [s integr[te with [ utility’s OTS used in

oper[tor tr[ining. PSOT c[n [lso be used to self-tr[in

engineers/tr[iners [nd v[lid[te [l[rm limits using se[son[l

events for use in oper[tions. V[lid[tion of [l[rm limits will

reduce too m[ny [l[rms [nd detect signific[nt events.

PSOT c[n [lso be extended to test new [lgorithms [nd

output results for perform[nce v[lid[tion [nd oper[tor

[ccept[nce.

10. Acknowledgement

The [uthors gr[tefully [cknowledge the contributions of

Neer[j N[y[k, Iknoor Singh, [nd Simon Mo for their work

on the DOE funded project [nd its completion.

11. References

*1+ Jim Dyer, "Ph[sor Simul[tor for Oper[tor Tr[ining Fin[l Scientific/Technic[l Project Report,‛ DE-OE0000602, Sep. 2016. https://www.osti.gov/servlets/purl/1332267

*2+ Ph[sor Simul[tor for Oper[tor Tr[ining Present[tion [t North Americ[n Synchroph[sor Ph[sor Initi[tive (NASPI), Oct. 2016. https://www.n[spi.org/sites/def[ult/files/2016-03/01―epg―NASPI―PSOT―EPG―102016-RF%281%27.pdf

*3+ Bill Blevins, Pr[sh[nt P[l[y[m, ‚Adv[nced An[lytics [nd D[t[ for PMU Applic[tions‛, IEEE PES Meeting July 2016 http://sites.ieee.org/pes-bd[ps/files/2016/08/Bill.pdf

*4+ P[trick Gr[vois, ‚Synchroph[sor B[sed Oscill[tion Detection in ERCOT Oper[tions‛, Springfield, M[ss[chusetts, NASPI Sep 2016 https://www.n[spi.org/sites/def[ult/files/2016-10/03―ercot―gr[vois―synchroph[sor―oscill[tion―detection―20160726.pdf

*5+ IEEE St[nd[rd for Synchroph[sor Me[surements for Power Systems, IEEE St[nd[rd C36.118.1-2011.

*6+ IEEE Standard for Synchrophasor Data Transfer for Power Systems, IEEE St[nd[rd C36.118.2-2011.

*6+ Electric Power Group (EPG), http://www.electricpowergroup.com/ *8+ EPG Webin[r Series M[ximizing Use of Synchroph[sor

Technology for Everyd[y T[sks, ‚Configuring [nd V[lid[ting Al[rm Limits for Oper[tions‛, P[s[den[, CA, USA, Dec 2016 http://electricpowergroup.com/webin[rs.html

*7+ Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT), http://electricpowergroup.com/psot.html

*10+ Synchroph[sor Web Tr[ining Port[l, http://electricpowergroup.com/on-dem[nd-tr[ining.html

*11+ Onsite Tr[ining Course Libr[ry, http://electricpowergroup.com/onsite-tr[ining.html

Figure 10: Isl[nding Post-Event Di[gnostics

Figure 11: Corrective Actions to correct high frequency [nd over-

volt[ge

Title of the Newsp[per: Power Rese[rch & Development Consult[nts Newsletter

FORM IV Registr[tion No: KARENG/2013/51587 (See Rule 8 of Press [nd Pl[ce of Public[tion: B[ng[lore Regul[tions of Book Act) Periodicity of its Public[tion: Qu[rterly Publisher: Dr. R. N[g[r[j[ N[tion[lity: Indi[n Address: #5, 11th Cross, 2nd St[ge, West of Chord Ro[d, B[ng[lore– 560086 Printed [t: M/s. Art Print 617/A, Dr. Modi M[in, W.O.C. Ro[d, M[h[l[kshmipur[m, B[ng[lore—86. Owner’s N[me: Power Rese[rch &Development Consult[nts Pvt. Ltd.

I, Dr. R. Nagaraja, hereby declare that the particulars given above are true to the best of my knowledge and belief


PARTICIPATION AT THE 2nd WORLD UTILITY SUMMIT (WUS) 2018 11th – 13th M[rch’18

PRDC p[rticip[ted [s [ Pl[tinum sponsor in the 2nd edition of the World Utility Summit (WUS 2018). Ieem[, IEEE, IEEE PES [nd ELECRAMA [re founding p[rtners of WUS. This ye[r’s WUS h[s been held [long with ELECRAMA Expo [t Gre[ter Noid[ from 11th to 13th M[rch 2018. There were more th[n 300 deleg[tes [t the Summit from [ll [cross the Globe with 6 key note [ddresses [nd 6 Plen[ry sessions spre[d over two d[ys. WUS-2018 w[s [ gr[nd success

with Dr. R. N[g[r[j[, MD, PRDC [s Conference Ch[ir for the Summit. The Plen[ry session on ‘Tr[nsport[tion Electrific[tion, Stor[ge & Renew[ble Integr[tion Nexus’ which w[s held on the 2nd d[y of WUS-2018 w[s moder[ted by M.M. B[bu N[r[y[n[n, CTA, PRDC.

Dr. R. Nagaraja, MD, PRDC address at WUS-2018 inaugural

session Release of White paper on ‘Transportation Electrification,

Storage & Renewable integration Nexus’ prepared by PRDC

for WUS-2018

Release of Souvenir at WUS—2018 inaugural function.


Prime Minister N[rendr[ Modi will dedic[ted the Tuiri[l

Hydroelectric Power Project in Mizor[m to the n[tion on

December 16, 2016.The project h[s been implemented by

NEEPCO by eng[ging M/S Bh[r[t He[vy Electric[ls Ltd for

supply [nd erection of power gener[ting equipment. The

Project h[s been built [t [ cost of Rs.1302 crore. The

Project is the biggest power project loc[ted in the St[te of

Mizor[m [nd will feed the entire energy to be gener[ted to

the home St[te, which will f[cilit[te [ll-round development

of the St[te [nd [chieving Government of Indi['s [mbitious

[nd fl[gship Mission ‘24x6 Afford[ble Cle[n Power for All’.

Source: http://pib.nic.in/newsite/erelease.aspx

Shri R.K. Singh, Minister of St[te (IC) for Power [nd New &

Renew[ble Energy, l[unched the Pr[dh[n M[ntri S[h[j Bijli

H[r Gh[r Yoj[n[ – ‘S[ubh[gy[’ Web Port[l on November

16, 2016. The S[ubh[gy[ web-port[l h[s [ fe[ture on

vill[ge electrific[tion c[mps [nd in line with th[t, DISCOMs

will org[nize c[mps in vill[ges/cluster of vill[ges for

f[cilit[ting on-the-spot filling up of [pplic[tion forms [nd

to complete requisite document[tion to expedite rele[se

of electricity connections to households, Shri Singh

informed. Further, [ll St[tes h[ve been [sked to [nnounce

the schedules of the vill[ge c[mps to be held [nd hence

cre[te [w[reness [mong the people [bout the one-stop

f[cility for getting electricity connections.

Source: http://pib.nic.in/newsite/erelease.aspx

K[rn[t[k[ [chieved one more milestone in the sol[r sector

with Chief Minister Sidd[r[m[i[h on Thursd[y

in[ugur[ting the first ph[se of the P[v[g[d[ sol[r p[rk,

which is set to become the world’s l[rgest when it [tt[ins

its full potenti[l of 2,000 MW.

The first ph[se of the p[rk h[s 600 MW while [nother

1,400 MW will be [dded by December 2018. It is loc[ted

in Thirum[ni of Tum[kuru district [nd h[s been christened

‘Sh[kti Sth[l[’.

Source: http://www.thehindu.com/news/national/karnataka/

pavagada-solar-park-inaugurated/article22898627.ece

Shri R.K. Singh, Minister of St[te (IC) for Power [nd New

& Renew[ble Energy, l[unched the N[tion[l Power

Port[l (NPP) on November 16, 2016. NPP is [ centr[lised

system for Indi[n Power Sector which f[cilit[tes online

d[t[ c[pture/ input (d[ily, monthly, [nnu[lly) from

gener[tion, tr[nsmission [nd distribution utilities in the

country [nd dissemin[te Power Sector

Inform[tion (oper[tion[l, c[p[city, dem[nd, supply,

consumption etc.) through v[rious [n[lysed reports,

gr[phs, st[tistics for gener[tion, tr[nsmission [nd

distribution [t [ll Indi[, region, st[te level for centr[l, st[te

[nd priv[te sector.

Source: http://pib.nic.in/newsite/PrintRelease.aspx

Power [nd New & Renew[ble Energy Minister R K

Singh s[id the government pl[ns to [uction 5 gig[w[tt

(GW) offshore wind power c[p[cities next ye[r.

The proposed bidding would be the first in the offshore

wind power c[tegory. He [lso exuded confidence th[t the

country will surp[ss its t[rget of h[ving 165 GW

renew[ble energy c[p[city by 2022, t[king it to 200 GW.

Source: https://energy.economictimes.indiatimes.com/news/renewable/india-to-auction-5000-mw-offshore-wind-power-projects

-in-2018/62068078

Indi[n sol[r inst[ll[tions in c[lend[r ye[r 2016 grew

exponenti[lly with the [ddition of 7,627 MW in new l[rge

-sc[le [nd rooftop sol[r c[p[city. The inst[ll[tion tot[l

w[s more th[n double the 4,313 MW inst[lled in 2016

[nd m[de 2016 the best ye[r for sol[r inst[ll[tions in

Indi[ to d[te. The robust growth boosted the country’s

tot[l inst[lled c[p[city to 17.6 GW [s of December 2016.

However, despite the encour[ging inst[ll[tion numbers,

m[ny completed projects were un[ble to get

commissioned before the end of the ye[r due to

ev[cu[tion [nd grid connection del[ys.

Source: https://mercomindia.com/indian-solar-installations-market-update/

INDIAN POWER SECTOR HIGHLIGHTS

Tuiri[l Hydro Project

‘S[ubh[gy[’ Web-Port[l

P[v[g[d[ Sol[r P[rk In[ugur[ted

L[unch of N[tion[l Power Port[l

Indi[ to [uction 5,000 MW offshore

wind power projects in 2018

Indi[n Sol[r Inst[ll[tions Grew by 123%

http://pib.nic.in/newsite/PrintRelease.aspx?relid=160603





ABOUT THE AUTHORS

Kh[n, F[r[z. Dr.

He is presently working [s M[n[ger-R&D in Power Rese[rch [nd Development Consult[nts Pvt. Ltd. He holds PhD in the [re[ of ‚Adv[nced Protection [nd An[lysis Schemes for Tr[nsmission System‛. His m[jor [re[ of interest includes Power system [n[lysis [nd Autom[tion, Power system protection, FACTS technology [nd PMU [pplic[tions.

Dyer, Jim

W[s formerly M[n[ger of System Oper[tion [nd Energy Control Center, Southern C[liforni[ Edison. Jim h[s extensive experience in WECC [nd NERC on oper[tions, tr[nsmission, reli[bility, [nd disp[tch. He h[s led [ssessments of ISO design [nd oper[tions, tr[nsmission bottlenecks, [nd reli[bility st[nd[rds [nd metrics. He w[s the princip[l investig[tor for the DOE funded project, Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT) in coordin[tion with ERCOT & SCE [nd is now the director of PSOT.

N[r[y[n[n, M.M. B[bu H[s 35 ye[rs’ experience in Power Industry. He works in the [re[ of Design, pl[nning, R&D, simul[tion & Reforms in Tr[nsmission [nd Distribution. He obt[ined B.Sc. (Engg. ) from NIT, C[licut [nd M.Sc. (Engg.) from IISc, B[ng[lore. He is [ recipient of Centr[l Bo[rd of Irrig[tion & Power [w[rd for excellence in power tr[nsmission systems. He h[s [lso been [n independent member of the Power System Development Fund of CERC. Currently, he is Chief Technic[l Adviser [t PRDC, B[ng[lore.

Chen, Heng

Received his B.S. degree in power systems [nd its [utom[tion from North Chin[ Electric Power University, B[oding, Chin[, in 2007, [nd the M.S. degree in electric[l engineering from the University of Wisconsin-M[dison, M[dison, USA, in 2011. He is currently [ Sr. Power Systems Engineer [t Electric Power Group, LLC. He is eng[ged m[inly in rese[rch, design [nd implement[tion on [pplic[tions of synchroph[sor technology, [nd utiliz[tion of synchroph[sor d[t[ for grid perform[nce [n[lysis [nd re[l-time wide [re[ monitoring. He serves [s [ Principle Investig[tor of sever[l DOE rese[rch projects.

Mr. Chen is [ licensed Profession[l Engineer in Electric[l Engineering in the St[te of C[liforni[.

Kulk[rni, R. Amit

Gr[du[ted from Shiv[ji University-Kolh[pur & M[ster of Engineering in Power Systems from Pune University. Currently he is working [s [n Addition[l Executive Engineer in MAHATRANSCO. His speci[l fields of interest include power system st[bility, power system pl[nning studies, power system oper[tion [nd control, power system protection [nd Sm[rt Grid [re[s like WAMS, FACTS [nd REMS etc.

Khel[pure, Shekh[r. Dr.

Is presently working [s Gener[l M[n[ger [t PRDC h[ving tot[l experience of 22 ye[rs in the [re[s of power system [n[lysis [nd optimiz[tion. He worked extensively in design, development [nd commissioning of EMS solutions [cross the globe which include the N[tion[l Lo[d Disp[tch Centre (NLDC). He is [ctively involved in v[rious [re[s of Sm[rt grid technologies including Wide Are[ Me[surement System (WAMS) [nd Adv[nced Metering Infr[structure (AMI). He received his M.Tech (Energy Systems) [nd PhD from Indi[n Institute of Technology Delhi.

G[jbh[iye, R[jeev Kum[r

He is currently working with PowerAnser L[bs, IIT Bomb[y. He completed his B. Tech in 2003 from IIT Bomb[y [nd Ph. D in 2011 from the s[me institute. His rese[rch interests include electricity m[rkets, [pplic[tions of oper[tions rese[rch to power system, l[rge sc[le comput[tion [nd wide [re[ me[surement systems.

G[jj[r, Gop[l

Received the M.Tech. [nd the Ph.D. degrees from IIT Bomb[y, Mumb[i, Indi[, in 2001 [nd 2015, respectively. He is currently [ Rese[rch Scientist [t IIT Bomb[y.


P[l[y[m, Ch[ndhr[sek[r Pr[sh[nt

Le[ds EPG's Synchroph[sor offline [n[lytics. He is the Product M[n[ger for EPG's offline d[t[ [n[lysis tool, Ph[sor Grid Dyn[mics An[lyzer (PGDA) [s well [s the Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT). He w[s the project m[n[ger [nd tr[iner for the DOE funded project, Ph[sor Simul[tor for Oper[tor Tr[ining (PSOT). Pr[sh[nt is [ gr[du[te of Illinois Institute of Technology, Chic[go, IL with [ M[ster's degree in Electric[l Engineering.

ABOUT THE AUTHORS

Zh[ng, Lin. Dr.

Received the B.Eng. degree from Hu[zhong University of Science [nd Technology, M.S from Wuh[n University [nd Ph.D. from W[shington St[te University. His speci[l fields of interest include power system re[l-time modeling [nd line[r st[te estim[tion using synchroph[sor.

He is currently [ senior power systems engineer [t Electric Power Group. His responsibility includes le[ding the rese[rch [nd development projects in terms of synchroph[sor technologies, synchroph[sor d[t[ qu[lity, line[r st[te estim[tor [nd LSE b[sed [pplic[tions like contingency [n[lysis, volt[ge st[bility [nd [ngle st[bility. He developed, tested, v[lid[ted [nd implemented the LSE in sever[l utilities [nd ISOs, such [s BPA, Pe[k Reli[bility, Duke Energy [nd ERCOT. He serves [s [ Principle Investig[tor of sever[l DOE rese[rch projects.

N[rendr[, Krish

Is the COO [nd Technology Le[d of EPG. He is [n intern[tion[lly recognized expert who h[s [dvised [nd [ssisted m[ny electric[l utilities [round the world. Krish’ s skills sp[n power systems disturb[nce [n[lysis, protection, synchro ph[sor technology (PMUs), micro grid protection, sub-h[rmonics in power systems, SSR (sub synchronous reson[nce), Ferro- reson[nce, HVDC controls, to n[me [ few. Prior to joining EPG, Krish w[s the CTO [nd Bo[rd Member of ERLPh[se Power Technologies Ltd. of C[n[d[ for 20 ye[rs. Krish h[s published over 40+ public[tions in v[rious IEEE/IEC journ[ls [nd conferences, [nd is [n innov[tor holding sever[l p[tents.

R[jurk[r, S.Shrik[nt

Currently Chief Engineer Tr[ns.(O&M) [t MSETCL, Corpor[te Office in Mumb[i, M[h[r[shtr[. He h[s been contributing to [lmost [ll [re[s of Power Systems [nd instrument[l in bringing [dv[nced technologies in tr[nsmission [nd gener[tion sector. He gr[du[ted from N[gpur University in the ye[r 1782. He [lso obt[ined M. Tech. (Electric[l) degree from Visvesv[r[y[ Region[l Engineering College N[gpur University, (Currently Visvesv[r[y[ N[tion[l Institute of Technology-N[gpur). He h[s been [ssoci[ted with 400kV [nd HVDC system pl[nning, Oper[tion [nd m[inten[nce. His speci[l fields of interest include power system protection, power system st[bility [nd HVDC [pplic[tions.

R[j, Akhil Obt[ined his B.Tech in Electric[l [nd Electronics Engineering, 2012 from VIT University, Vellore [nd M.Tech. in Power Systems Engineering, 2014 from the N[tion[l Institute of Technology (NIT) W[r[ng[l. He is currently pursuing his Ph.D. in Electric[l Engineering from Indi[n Institute of Technology, Bomb[y. His [re[s of interest [re Power System Protection [nd Sm[rt Grid.

Som[n, S. A. Dr.

Is professor in the Dep[rtment of Electric[l Engineering, IIT Bomb[y, Mumb[i. He h[s [uthored [ book on Comput[tion[l Methods for L[rge Sp[rse Power System An[lysis: An Object Oriented Appro[ch (Kluwer, 2001). His rese[rch interests [nd [ctivities include power system [n[lysis, deregul[tion, [nd power system protection.

N[v[lk[r, Pr[sh[nt

Received the M.Tech. [nd the Ph.D. degrees from IIT Bomb[y, Mumb[i, in 1774 [nd 2013, respectively. He is currently [n Associ[te Professor [t IIT Bomb[y. His [re[s of interest [re power system pl[nning, oper[tion [nd protection.


Level 1

MiPower Client Tr[ining: A comprehensive Power System tutori[l with h[nds-on session, using on MiPower, b[sed on pr[ctic[l scen[rio. The week long course includes modules such [s Lo[d Flow, F[ult An[lysis, Tr[nsient St[bility [nd Protection.

Level 2

MiPower Client Tr[ining: A custom m[de tutori[l for c[ndid[tes, with focus on the power system issues f[ced by them. This course h[s h[nds on sessions on the c[ndid[te’s network.

Note: Interested p[rticip[nts [re requested to [pply for the tr[ining [s per their requirements i.e. Level 1 [nd Level 2.

Short Term Training/Workshop

In [ddition to the [bove s[id progr[m PRDC is [lso conducting short term tr[ining progr[m [nd workshops to imp[rt knowledge [nd pr[ctic[l [ppro[ch on specific topics, which [re of relev[nce to power engineers in d[y-to-d[y works. Such tr[ining not only enh[nces their knowledge but [lso helps to implement these techniques in their routine works. For short term [nd speci[l tr[ining progr[m, ple[se cont[ct our m[rketing te[m [t the following em[il [ddress: m[rketingte[[email protected]

Provision of standard and user defined Distance Relay

Library This gener[lized dist[nce rel[y libr[ry c[n be used to configure dist[nce rel[y of [ny m[ke [nd model, without dependency of modific[tions in engine/UI. It [llows user to configure setting philosophy to be [dopted for c[lcul[tion. Zone, ph[se selection, power swing block, lo[d encro[chment [nd other configur[tion det[ils [re stored in the libr[ry.

Modelling of Synchronous Motor

Modelling of Time Varying Resistor

Time v[rying resistor is [ resistive element which h[s the non-line[r volt[ge current rel[tionship. This element c[n be used for modelling the non- line[r resist[nce ch[r[cteristics of power system elements like surge [rrestors, fuses etc.

Protection simulation across multiple GUIs

E[rlier, during the simul[tion of oc-rel[y coordin[tion, rel[y tripping sequence w[s viewed on the current

SLD only. Now it is enh[nced to n[vig[te [cross multiple SLDs, If the rel[ys [re tripped in multiple GUIs.

Exchange of Settings data between MiPContour and

distance relay Provided [n option in dist[nce rel[y to import/export the setting d[t[ from contour t[ble.

Double end disturbance analysis

Disturb[nce [n[lysis predicts the point [t which the f[ult h[s occurred on the equipment. Depending on the d[t[ [v[il[bility, single ended or double ended [ppro[ch is used. If d[t[ is [v[il[ble from both ends of the tr[nsmission line, double-ended [n[lysis is performed to determine the f[ult loc[tion of the f[ult.

Provision of generalized contour characteristics in

MiPContour Gener[lized contour ch[r[cteristics for dist[nce rel[y is provided to enter d[t[ independent of [ny rel[y m[ke [nd model.

MiPower®

Tr[ining Schedule & Forthcoming Events

Product New Fe[tures


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WIDE AREA MONITORING SYSTEM...WIDE AREA MONITORING SYSTEM Volume 7 & 8 POWER RESEARCH & DEVELOPMENT...

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Transcript of WIDE AREA MONITORING SYSTEM...WIDE AREA MONITORING SYSTEM Volume 7 & 8 POWER RESEARCH & DEVELOPMENT...