Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Harmonic filter design forelectrified railwaysDIgSILENT USER GROUP

Sydney — 5 September 2013

M Jansen, S Hagaman, T George

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Introduction

I Railway electrification projectI Adds significant unbalanced non-linear load to the gridI PowerFactory used for

I Harmonic emission/complianceI Filter design/ratingI EMT reviewI Protection design

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Feeder station topology

TNSP Network

132 kV

RL1 RL2 RL3 HF1 RL4 RL5 RL6 HF2

50 kV

(AB) (BC)

T1 T2

Note: (AB)/(BC) phasing is typical

I Requires single phase compensationI Limited output power

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Emission limits

Emis

sion

lim

it (%

of V

1)

0

0.5

1.0

1.5

Harmonic orderTHD 7 13 19 25 31 37 43 49

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Range of network conditions

Net

wor

k im

peda

nce

(Ω)

10

100

1000

Frequency (× 50 Hz)0 5 10 15 20 25 30 35 40 45 50

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Current spectra

MeasuredExpandedUsed

Cur

rent

em

issi

on (%

of V

1)

0.001

0.01

0.1

1

10

Harmonic orderTHD 7 13 19 25 31 37 43 49

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Voltage distortion without filters

PoC

vol

tage

dis

torti

on (%

of V

1)

0.001

0.01

0.1

1

10

Harmonic orderTHD 7 13 19 25 31 37 43 49

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Filter configuration

Shunt Third Fifth Ninth

Phase A

Phase B

From 50 kV switchroom

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Voltage distortion with filters

PoC

vol

tage

dis

torti

on (%

of V

1)

0.001

0.01

0.1

1

Harmonic orderTHD 7 13 19 25 31 37 43 49

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Filter parameters

Rating C L Rp Tuned toBranch Type (Mvar) (µF) (mH) (Ω) (Hz)

Shunt — 20 — 398 — —Third Single tuned 7 7.92 142 — 150Fifth Damped 5 6.11 66.3 800 250Ninth Damped 18 22.6 5.53 50 450

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Component ratings

Capacitor VN Reactor IRMS Resistor PR(kV) (A) (kW)

Third 78.2 178.78 –Fifth 64.8 117.21 16Ninth 61.0 414.45 80

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Electromagnetic study

I Design for electromagnetic transient (EMT) phenomena

I Peak voltage across capacitor banksI Peak currentsI Protection setting stability

I Studies for switching transients and lightning surgesI Specification of mitigation measures

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Model augmentation for EMT study

TNSP Network

132 kV

RL1

RL2

RL3 HF1 RL4 RL5

RL6

HF2

50 kV

T1 T2

Stray capacitance

Surge arrester

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

PowerFactory simulation

I Operational scenarios to define different switchingarrangements

I 1 or 2 transformers onlineI 1 or 2 filters onlineI Several different track feeder arrangementsI Lightning strike points

I Study cases for each switching/lightning caseI Analysis of different point on wave switchingI DPL scripts to automate study cases, print plots and

analyse waveforms

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Switching study

VC3 VC5 VC9

Cap

acito

r vol

tage

(kV)

0

200

Time (s)0.02 0.04 0.06 0.08 0.10

I3 I5 I9

Bran

ch c

urre

nt (k

A)

−1

0

1

Time (s)0.02 0.04 0.06 0.08 0.10

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Mitigation measures

I Switching transientI Surge arresters specified across the 3rd tuned branch

capacitor bank (approaching IEC 60871-1 peak limit)I Overcurrent protection graded to avoid spurious trips on

filter energisationI Lightning surge

I Surge arresters specified for the filter busbars

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Capacitor bank voltages with surge arresters

175.4 kV

-205.9 kV

IEC 60871 voltage withstand limit

V C3 (

kV)

−200

0

200

Time (s)0.005 0.010 0.015 0.020

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Surge arrester current — PoW switching

PoW time 6 ms, Ipeak = -380 A

I MO

V (k

A)

−0.4

−0.2

0

Time (s)0.005 0.010 0.015 0.020 0.025 0.030

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Surge arrester current — Lightning

Cur

rent

(kA)

0

10

Time (ms)−0.1 0 0.1 0.2

Ener

gy (k

J)

0

20

Time (ms)−0.1 0 0.1 0.2

Introduction

Harmonicimpact study

Filter design

EMT study

Conclusion

Conclusion

Thank you for your time

Questions?