© Copyright 2009 ABB. All rights reserved. - 1 -04/21/23

Development and testing of 1100 kV GIS

HOLAUS Walter, RIECHERT Uwe, SOLOGUREN Diego, KRÜSI Urs

ABB Switzerland Ltd.

IEC/CIGRE UHV Symposium, New Dehli 29.-30.01.2009

ELK-5 equipment at ”Jingmen” substation

© C

opyr

ight

200

9 A

BB

-

2 -

Dr. HOLAUS Walter

Development of UHV GIS: Environment

Only a few potential markets worldwide e.g. China, India, .. Huge development effort for a limited number of customers

Chinese market supplied by local suppliers

International standards (so far) do not cover 1100 kV AC Development is based on customer specification

Limited possibilities to test 1100 kV GIS equipment Only a few test labs worldwide are equipped for UHV testing

Test items and test poles tend to be huge -> transport & space limitations

Rated power of one UHV GIS bay is 6‘9 GW Robustness is key factor for UHV GIS and other components

Substation layouts to support high availability

ABB finished UHV GIS development and type testing in 2008 Equipment assembled by Xian Shiky in China

Equipment is installed and in operation at “Jingmen” substation

© C

opyr

ight

200

9 A

BB

-

3 -

Dr. HOLAUS Walter

ELK-5 GIS: Main ratings

Um 1100 kV System Voltage 1000 kV Rated lightning impulse withstand level 2400 kV Rated short-duration pfwv to ground 1100 kV, 1 min Rated short-duration pfwv across isol. distance 1100 + 635 kV Rated lightning impulse wv. across open gap 2400 + 900 kV Rated switching impulse wv. to ground 1800 kV Rated switching impulse wv. across open gap 1675 + 900 kV Rated frequency 50 Hz Rated normal current for feeder circuits 4000 A Rated normal current for main busbar circuits 8000 A Rated short time withstand current 50 kA, 3s Rated peak withstand current 125 kA Partial discharge level of each GIS component <3pC at Um/3

© C

opyr

ight

200

9 A

BB

-

4 -

Dr. HOLAUS Walter

Layout proposal for Hybrid GIS, 2 CB layout

18.5 m

DES

CT

CB

Closing resistorCB drive

Top view 1 phase:

BB1

BB2

Exit

15 m

© C

opyr

ight

200

9 A

BB

-

5 -

Dr. HOLAUS Walter

Layout characteristics

All GIS equipment close to floor level

“Hook” shape compensates elongations

All drives placed within 1.5 m height

Density sensors close to floor level

No platforms required for GIS installation

CB drive and CB tank can be removed without disassembling other GIS parts

Only small steel structures required

Biggest transport unit less than 8 tons

Most spacers are arranged vertically

© C

opyr

ight

200

9 A

BB

-

6 -

Dr. HOLAUS Walter

Design of 1100 kV circuit breaker

Circuit breaker: 4 interrupters

Closing resistorCO switch

Drive

Linkage

9300 mm

CB

Switch R

Existing interrupting units applied

4 interrupter units connected in series,

A high-speed switch for closing resistor

One drive operating interrupters and switch

Closing resistor in separate tank as an option

Overall weight: 7.5 tons

© C

opyr

ight

200

9 A

BB

-

7 -

Dr. HOLAUS Walter

Drive energy for 1100 kV circuit breaker

aTarc

iiOdrive Eiti

gapmmE 100

2

min,0, 2

1

Calculation of drive energy

4 interrupting units connected in series require the least drive energy for 1100 kV

Using less interrupting units increases opening speed and drive energy demand

Result

i1

Circuit breaker

i2 i3 ix

Drive

Min. distance: 370 mmMin. arcing time 10 ms

0

5000

10000

15000

20000

25000

30000

35000

0 1 2 3 4 5 6 7 8# of int.units

[J]

0

5

10

15

20

25

30

35

[m/s]

Opening speed

Drive Energy requirement for O

Drive Energy requirement for O-CO

© C

opyr

ight

200

9 A

BB

-

8 -

Dr. HOLAUS Walter

Thermal dimensioning of closing resistor

2 x Phase opposition within 30 min,

11 ms pre-insertion each

Resistance value: 560 Ohm at 20°C

Starting temperature 50 °C

Cooling time constant: 3000 s

Example: Assumptions for simulation

Resistance value changes due to Temperature Voltage

Dissipated Energy 91.7 MJ

Temperature rise 120.3 °K

Max temp of resistor discs 170.3 °C

Results for this simulation

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.04350

400

450

500

550

Time (s)R

esis

tanc

e (O

hm) Resistance (Ohm)

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.040

50

100

Time (s)

Ene

rgy

(MJ)

Energy (MJ)

0 0.005 0.01 0.015 0.02 0.025 0.03 0.035 0.040

50

100

150

Time (s)

Tem

pera

ture

ris

e (°

K)

DeltaT (°K)

Cooling during 30 min

First PO insertion Second PO insertion

Resistance Ohm

Energy MJ

Temperature K

© C

opyr

ight

200

9 A

BB

-

9 -

Dr. HOLAUS Walter

Size comparison ABB circuit breaker & drive

300 kV

550 kV

550 kV with closing resistor

1100 kV with closing resistor

Closing resistorCO switch

1 interrupter

Linkage

2 interrupters

2 interrupters + closing resistor

4 interrupters

HMB 4

HMB 8

HMB 8

HMB 16

© C

opyr

ight

200

9 A

BB

-

10 -

Dr. HOLAUS Walter

Size comparison ABB circuit breaker & drive

300 kV

550 kV

550 kV with closing resistor

1 interrupter

2 interrupters

2 interrupters + closing resistor

HMB 4

HMB 8

HMB 8

© C

opyr

ight

200

9 A

BB

-

11 -

Dr. HOLAUS Walter

Voltage grading along the 4 interrupters

Voltage grading capacitance Inner: CP=2.5 nF, Outer: CP=2.7 nF

Stray capacitance: CE=75.5 pF AC 50 Hz calculations Voltage grading factor: 1.056

Simulation circuit

Series resistance: 25 Ohm Inductance: 500 nH Using worst-case

assumptions for tolerances Specific calculations required

for half-pole testing

Static calculations

Dynamic voltage distribution

© C

opyr

ight

200

9 A

BB

-

12 -

Dr. HOLAUS Walter

Dielectric Type Tests

Lightning impulse voltage Overshoot of 7 – 10 %

Combined voltages Overcoupling of 20 %

PD measurement Background noise level of 7 pC

at 1000 kV Non-conventional PD

measurement methods (UHF)UHV PD Sensor 1

UHV PD Sensor 2

UHV PD Sensor 3UHV PD

Sensor 4

AC: 1100 kV, 1 min

AC-AC: 1100 + 635 kV

LI-AC: 2400 + 900 kV

SI: 1800 kV

SI-AC 1675 + 900 kV

Specific remarks

© C

opyr

ight

200

9 A

BB

-

13 -

Dr. HOLAUS Walter

Power tests on UHV Circuit breaker Breaking and switching tests at

XIHARI lab as half-pole tests Two interrupters under test

The other two breaks act as auxiliary breaker.

T100a and T100s additionally as full-pole tests TRV voltages at both sides of

the circuit breaker

The enclosure was connected to one side TRV

© C

opyr

ight

200

9 A

BB

-

14 -

Dr. HOLAUS Walter

Examples: TRV’s from power testing

T100a

Major loop

Half pole test

T100a (half pole test major loop)

-600

-400

-200

0

0 0.5 1 1.5 2 2.5 3

N080293Requirement

RRRV = 1.2

Voltage

Time [ms]

T60 (half pole test)

-1000

-800

-600

-400

-200

0

0 0.2 0.4 0.6 0.8 1 1.2 1.4 1.6 1.8 2

N080427Requirement

RRRV = 2.2

Voltage

Time [ms]

T60a

Half pole test

© C

opyr

ight

200

9 A

BB

-

15 -

Dr. HOLAUS Walter

Making Tests T100s(a) Laboratories have synthetic making

circuits capable to ignite 550 kV CB For longest pre-striking arc in the

1100 kV breaker, SF6 pressure was reduced to 0.2 MPa

The pre-arcing time of the 1100 kV circuit breaker with four breaks was similar to the pre-arcing time of a 550 kV circuit breaker with two breaks of the same design.

Advantages by reducing pressure Simple measure to perform a

making test without having the full making voltage available.

Multiple making operations without disassembly

Correct mechanical forces for the drive

Correct pre-arcing distance

© C

opyr

ight

200

9 A

BB

-

16 -

Dr. HOLAUS Walter

Design of TV5 disconnector

Designed as 90 ° angle disconnector

Existing DES drive from ABB 550 kV applied

No linkage between the three phases

No VFT resistor applied VFT calculations show, that VFT resistor is

not required. VFT levels remain below 2.2 pu.

BIL levels is 2.6 pu. This provides margins for VFT stress.

Enclosure as welded construction

Contact area optimized for improved bus transfer switching capability

Earthing switch as an option

Simple design with small number of parts

Antrieb

FestkontaktBewegter Kontakt

Isolator Isolator

Drive

Moving contact Fixed contact

Insulator Insulator

Active parts of disconnector

© C

opyr

ight

200

9 A

BB

-

17 -

Dr. HOLAUS Walter

UHV Disconnector switching tests at STRI lab

TD1, TD2, TD3 tests performed

Huge effort for testing Max. VFT peaks of

2.23 pu measured Confirmed simulations

Average arcing time 280 ms at TD2

Test set-up for disconnector switching tests in STRI, Ludvika, Sweden Test circuit TD2

© C

opyr

ight

200

9 A

BB

-

18 -

Dr. HOLAUS Walter

Conclusions UHV GIS equipment rated 1100 kV, 4/8 kA, 50 kA has been designed

and fully type tested

Design of the UHV GIS components has been done for optimum layouts and flexibility in GIS or hybrid GIS substations

Energization done in 12/2008 at Jingmen substation in China

Although test laboratories have invested in facilities for testing at UHV voltage levels, type testing remains a very challenging task