solution for power evacuation of tanjung jati power plant

PLN:

Susanto WIBOVO

Singal SIHOMBING

Onda IRAWAN

Munawar FURQAN

AREVA T&D, Systems :

A-MAHER

Solutions for power evacuation of TANJUNG JATI POWER PLANT

March 2007

JAKARTA

PLN-AREVA - March 20072 2

Brief Conclusion Of Results

In normal operation

Even with reconductoring of the 150 kV lines, and addition of two more 150 kV lines, voltage level at Ungaran 500 kV is at its low limit

Series compensation of 500 kV lines prevents, primarily, under voltage in normal operation, in all cases , even without any modification in 150 level. The voltage conditions in post-fault period is also good.

It is important to be noted that, series compensation at Ungaran side of the lines permits to obtain very good results without any modification at 150 kV level. Specially, if these modifications are not necessary for area loading

In normal conditions 150 kV lines should not be used to transfer considerable power instead of 500 kV lines, as it generates 9 times more losses.


Brief Conclusion Of Results

In N-1 contingency; one 500 kV line is tripped:

For faulted conditions, with trip of one line, one generator is also temporarily tripped.

Temporary trip of one generator prevents any probable 500 kV line over loading, and it is supported by the system

A CIGRE reference is enclosed about this method

Ungaran 150 kV switch gear short circuit level

A 12 ohms series reactor is inserted into bus-coupler bay, with proposed operational method (see, the explanations)


Introduction

Subject introduction:

Two additional 600 MW units are planned for installation adjacent to the existing Tanjung- Jati power plant.

To investigate possible evacuation scenarios of the additional powers of the power plant PLN-Areva performed a joint study.

A preliminary meeting was held on Friday 30th March at PLN-PUSAT office; the followings were present:

PLN;

Susanto WIbovo

Singal Sihombing

Onda Irawan

Areva;

Liasta Singarimbun

Gregoire Bour

A - Maher

In this meeting, investigation scenarios were generally discussed, and from Monday, April 02, 2007, the calculation and studies were performed.

Objective of the present analysis is to determine the optimum solution for injection of the added power into the network taking into consideration the cost, right of way difficulties and time required of the construction of the solutions.


Studied Scenarios

Possible studied scenarios:

Configuration 1

Power plant is composed of 4 generators and two 500/150 kV transformers.

500 kV lines are only the two existing ones going to Ungaran.

The 150 kV transmission lines connected to the two power transformers, supply local area loads, and provide somehow a parallel rout to the two 500 kV lines to 500 kV system.

No Series compensation is added to the 500 kV lines

In this configuration two 150 kV lines are over loaded to 116% of their rated ampacities.

The voltages at Syung and Tbrok, 150 kV are low; 94% & 93%

Each 500 kV line is loaded to1100 MVA. The thermal capacity of each line is about 1985 MVA.

The voltage at Ungaran 500 kV is low; 94.9%

For a normal operation, this configuration, it is not acceptable


Studied Scenarios

Configuration 2 The same configuration as above, but the conductors of the 150

kV lines are replaced with new conductors having about two times ampacity as the existing ones, but with the same weight.

Overload of the 150 kV lines are removed. But, voltage at Ungaran 500 kV is low; 95%.

The voltage level of the PRW15(150 kV bus) is low. The reason is that the power flows down to KUDUS and then returns to consumer substations of SYUNG and TBROK. That is why the additional lines between Tanjung-Jati and Syung are proposed, in configuration 3.

When one 500 kV line of Ungaran is opened, the remaining line takes about 1910 MVA, which is less than thermal capacity of the line, and voltage at Ungaran 500 kV is low; 91%.

But, when, the line conditions, and system stability is studied after removal of a line fault, the remaining line may trip, see the study results.

So, for normal operation, some compensation is necessary, specially if the proposed 150 kV modifications are not implemented.


Studied Scenarios

Configuration 3

With configuration number 2, Two 150 lines are added between Tanjung jati and Syung.

Even with these additional 150 kV lines, the voltage at Ungaran 500 kV is low; 95.5%.

Therefore, if, the mentioned extensions are delayed, the voltage would be still lower.

When one 500 kV line trips, resulted conditions are similar to the previous case.

For normal operation 95.5%, seems low, some compensation will improve the conditions considerably (see config 5), specially if the proposed 150 kV modifications are not implemented.


Studied Scenarios

Configuration 4

This configuration is the configuration 1; only existing system, with series compensation of the 500 kV lines.

500 kV lines are only the two existing ones going to Ungaran.

The voltages, (figure of this simulation is not available to author), The voltage at Ungaran 500 kV is very good

Detailed simulation results will be placed here by PLN


Tripping a generator in case of a fault in one of the 500 kV lines


Configuration number 5; steady state operation:

Equivalent to configuration 3, but with about 60% series compensation on 500 kV lines.At steady state all voltage conditions become perfect: 98.3%, for normal operation, and 97% for one line steady state operation.Faulted operation results , se later in this report

Configuration number 5:

Config. 3; plus series compensation, in faulted conditions


Configuration number 6; steady state operation:

At steady state voltage conditions are not good

Faulted operation results , see later in this report, when one generator is tripped, the conditions become almost acceptable for a contingency period

For faulted conditions, with trip of one generator, Ungaran voltage is about 94%


Config. 3; in faulted conditions


Simulation data and results


Configuration number 1; with existing 150 kV lines


Configuration number 2; 150 kV lines are reconductoredSteady state conditions;

Still, Ungaran voltage is at low limit: 95%Comments; reconductoring can be justified, if 150 kV loads are high


Configuration number 2, 150 kV lines are reconductored


Configuration number 2, one 500 kV line is out;150 kV lines are reconductored

One 500 kV line is out, but without any fault, atsteady stateThe remaining line power(2030 MVA) is slightly higher than thermal limit of line(1985 MVA) Ungaran 500 kV bus voltage is very low(90.8%)The conditions are not acceptable

When line is tripped due to a fault, conditions will be worse

N-1, in Configuration number 2


one 500 kV line is out, but without any fault


Configuration number 3;150 kV lines are reconductored and;Two 150 kV lines are added between Tbrok & Syung

Both 500 kV lines are in at steady stateOperating conditions are almost normal

Ungaran 500 kV bus voltage is still low(95.5%)The voltage conditions for steady state are not very favourable



Configuration number 3


N-1, in configuration number 3; steady state:

150 kV lines are reconductored and;Two 150 kV lines are added between Tbroka & Syungone 500 kV line is out, but without any fault;Steady stateThe remaining line power(1905 MVA) is slightly smaller than thermal limit of line(1985 MVA) Ungaran 500 kV bus voltage is still very low(91.8%)These conditions are not acceptable

When line is tripped due to a fault, conditions will be worse



One 500 kV line is out, but without any fault at Steady state


N-1 of configuration number 3, but in faulted conditions ;150 kV lines are reconductored and;Two 150 kV lines are added between Tbroka & Syung

A 3-ph fault is simulated on a 500 kV line close to power plant and is removed after 90 ms;The remaining line power is about 2000 MVA, it is slightly higher than thermal limit of line(1985 MVA);In case 150 kV loads are less than what is declared, this line would trip too. Ungaran 500 kV bus voltage is still very low(92%)The conditions are not acceptable

Nevertheless the system stability is not lost; (see, 3 coming slides)

Configuration number 3, faulted N-1


LOADING OF UNGARAN-TJATI & IBT 500/150 kVCONFIG-3 (3 PH FAULT AT 1 CKT UNGRAN-TJATI)

UNGARAN-TJATI 500 kV

IBT 500/150 kV


VOLTAGE AT UNGARANCONFIG-3 (3 PH FAULT AT 1 CKT UNGRAN-TJATI)

ROTOR ANGLE STABILITY CONFIG-3 (3 PH FAULT AT 1 CKT UNGRAN-TJATI)


Configuration number 5;Equivalent to configuration 3, but with about 60% series compensation on 500 kV lines.At steady state all voltage conditions become perfect: 98.3%, for normal operation, and 97% for one line steady state operation.

Configuration number 5; series compensation;

steady state operation


Equivalent to configuration 3, but with about 60% series compensation on 500 kV lines.

A 3-ph fault is simulated on a 500 kV line close to power plant and is removed after 90 ms;The remaining line power is about 2000 MVA, it is slightly higher than thermal limit of line(1985 MVA);Ungaran 500 kV bus voltage is good (97%)The voltage conditions are good, but from power carrying point of view, there is possibility of the line tripping, specially, in case 150 kV loads are less than what is declared, this line may trip too. For such an important power outlet, this risk should not be taken

System stability is not lost

Configuration number 5; series compensation; faulted conditions


Configuration number 5; faulted conditionsProposed solution

In order to remove the eventual probability of the remaining line trip, one of the generators is intentionally tripped simultaneously with the faulted line.

This action removes MVA constraint of the line.

And as can be seen from the three coming slides, All points from stability point of view are also all right.

Incidentally the combination of the loads are such, that tripping one generator removes that much of power, which line load becomes about 1500 MVA. With such resulted loading, we may not need series compensation.

Nevertheless, series compensation for normal operation is needed

Voltage at Ungaran without compensation, in similar conditions, is about 94%


Configuration number 5; faulted conditionsProposed solution, summary

upon detection of a fault at any of the two lines, along with line trip order, a trip signal is also sent to one of the generators. This action automatically brings the power of the line within the thermal capacity of it. The tripped unit power is supplied and replaced by the spinning reserve of the network.And as can be seen from the three coming slides, All conditions are all right.

Series compensation of lines prevents, primarily, under voltage in normal operation, and also in post-fault condition.

For faulted conditions, with trip of one generator, series compensation effect is less

Temporary trip of one generator prevents any probable 500 kV line over loading.


Configuration number 5; series compensation; normal operation


LOADING OF UNGARAN-TJATI & IBT 500/150 kVCONFIG-5 WITH SERIES CAPASITOR(3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)


VOLTAGE LEVEL AT UNGARAN 500 KVCONFIG-5 WITH SERIES CAPASITOR(3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)

ROTOR ANGLE STABILITY CONFIG-5 WITH SERIES CAPASITOR(3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)



Config. 3; in faulted conditions


Configuration number 6; no compensation;generator tripping upon line fault :

In normal operation prior to fault occurrence, Ungaran 500 kV bus voltage is low(95.5%)The voltage conditions for steady state are not favourable.

Temporary trip of one generator prevents any probable 500 kV line over loading, in this case too.For faulted conditions, with trip of one generator, Ungaran voltage is about 94%

LOADING OF UNGARAN-TJATI & IBT 500/150 kVCONFIG-6 (3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)

UNGARAN-TJATI 500 Kv

IBT 500/150 kV


VOLTAGE LEVEL AT UNGARAN 500 KVCONFIG6 (3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)


ROTOR ANGLE STABILITYCONFIG-6 (3 PH FAULT AT 1 CKT UNGRAN-TJATI& TRIP 1 UNIT TJATI)


Short circuit level at Ungaran 150 kV sun-station


AL 3 X 4 X 400 mm2

PUDAKPAYUNGtower (33a - 33m)+34 - 69

10,912 kM

KRAPYAKtower 01 - 69

21,819 kM

II I

Mitsubishi PC 14 S

1600-1200-800-400/1A

III

AEG S1-170 F33150 A 40 kA

I.B.TI

500 MVA

II

500 MVA

1000/1 A 600/1 A1000-2000/1A

1000-2000/1A

KOPEL UGN.3

Rel 20 KV ALSTHOM 1250 A

III

TAMBAKLOROKtower 01 - 9529,100 kM

III

PURWODADItower 01 - 7956,784 kM

II I

BAWENtower 01 - 27

8,281 kMII I

JELOKtower 01 - 4516,569 kM

ABB LTB 170 D13150 A 40 kA

BBC-ELF 1703150 A 40 kA

AEG S1-170 F13150 A 40 kA

Siemens 3AQ1EE3150 A 40 kA

ABB IMBD 170 A4

2000-1000-300-150/1A

Mitsubishi PC 14 S

1600-1200-800-400/1AMitsubishi PC 14 S

1600-1200-800-400/1A

ABB - IMBD 170 A4

600-450-300-150/1A

ABB - IMBE 170 A4

2000-1600-800-400/1A

Mitsubishi PC 14 S1600-1200-800-400/1A

PS.1

Rel 22 KV MITSUBISHI - 1250 A

600/5 A 600/5 A

UPB.2PS.2

CADCADUGN.4

600/5 A600/5 A

UGN.2

600/5 A

UPB.1

25/5 A

Mitsubishi PC 14 S

1600-1200-800-400 /1A

Mitsubishi PC 14 S

1600-1200-800-400/1A

Mitsubishi PC 14 S

1600-1200-800-400/1A

Mitsubishi PC 14 S1600-1200-800-400/1 A

ABB - IMBD 170 A4

600-450-300-150/1A

Trafo 3-60 MVA

XIAN SFZ 150 kV / 20 kVImp: 13,31 %YNyn0

1600 A 1600 A 1600 A 1600 A 1600 A 1600 A 1600 A 1600 A 1600 A 1600 A

1600 A 1600 A

20 kA 20 kA 20 kA 20 kA 20 kA 20 kA 20 kA20 kA 20 kA20 kA

20 kA20 kA

20 kA20 kA

1600 A 1600 A 2500 A 2500 A

2500 A1600 A 1600 A 1600 A1600 A 1600 A 1600 A 1600 A1600 A

AEG S1-170 F3

3150 A 40 kA

AEG S1-170 F3

3150 A 40 kAAEG S1-170 F33150 A 40 kA

AEG S1-170 F33150 A 40 kA

AEG S1-170 F33150 A 40 kA

AEG S1-170 F33150 A 40 kA

AEG S1-170 F3

3150 A 40 kASiemens 3AQ1EE3150 A 40 kA

Siemens 3AQ1EE3150 A 40 kA

AEG S1-170 F33150 A 40 kA

AEG S1-170 F33150 A 40 kA

AEG S1-170 F13150 A 40 kA

Trafo 2-15 MVA

ASEA TBA 33150 kV / 20 kVImp: 11,7 %YNyn0(d1)

ABB - IMBE 170 A4

2000-1600-800-400/1A

Mitsubishi PC 14 S

1600-1200-800-400/1A

400 A 630 A 630 A 630 A

INC. II

630 A1250 A12,5 A 630 A 630 A

Bus Bar 150 kV

Mitsubishi PC 14 S1600-1200-800-400/1A

BusSection2500 A

Rel 20 KV MERLIN GERIN - 2500 A

200-400/1A 200-400/1A 200-400/1A 200-400/1A

630 A630 A 630 A630 A 630 A25 kA

INC. III

2500 A25 kA

200-400/1A

CAD CAD UGN.7CAD

200-400/1A

UGN.6

680 A

200-400/1A 200-400/1A

630 A630 A

UGN.5UGN.1

AL 3 X 2 X 400 mm2

AL 3 X 1 X 400 mm2

400 A 400 A 400 A

25/5 A 25/5 A 25/5 A

III

RJTD/FML/04-3028

Tanggal RevisiDisetujui

02-05-2006

GI 150 kV UNGARAN

DERI 01

Digambar Diperiksa

File: \\Evop1\D\Single Line Diagram\UPT semarang\GI Ungaran.cdr

PT PLN (Persero)

REGION JAWA TENGAH DAN DIYPENYALURAN DAN PUSAT PENGATUR BEBAN JAWA BALI

Unit Pelayanan Transmisi Semarang

CAHYONO MARDI S


Ungaran short circuit level

Total short circuit level at Ungaran 150 kV bus reaches to about 49 kA, and this is the case in all the configurations with very little difference

The contribution to this current is made from many feeders, therefore inserting series reactors to all the feeders is; firstly impractical from space and equipment point of view, secondly large voltage drops will be resulted on all feeders.

It is proposed to insert a series reactor (12 ohms) into the bus-coupler circuit, and one of each double circuit lines will be connected to one bus, the other to the second bus.


Ungaran short circuit level

Bus-coupler is kept closed, but usually very small power is flowing through it, therefore it has no adverse effect. Even when mismatch is temporarily equal to one feeder current its effect is not high.

Total short circuit level at Ungaran 150 kV bus, then reaches to about 40 kA. But any feeder breaker will have 40 kA minus its own contribution. So it is always much less than 40 kA. Short circuit level of each breaker can be calculated by PLN, to have detailed values


Simulation with three 500 kV lines

A third line is added between TANJUNG JATI and MANDIRANCAN

The 150 kV modifications are also included

N-1 conditions and normal conditions are all right

The short circuit level of the Ungaran 150 kV should however be corrected.

solution for power evacuation of tanjung jati power plant

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