paper 149

STABILITY ENHANCEMENT

OF GUJARAT GRID

THROUGH SHUNT

COMPENSATION

By

1. Yagnik Utsav P. (M.E. Scholar, SSEC)

2. Solanki Mehul D. (Asst. Prof., SSEC)

Electrical Engineering

Paper ID - 149

04 April 2016 NCERTE-2016 1

Outline


• Abstract (4)

• Network Considered (5)

• Network Parameters (6)

• Why this network? (7)

• Other considerations (8)

• Computation using Power World Simulator (9)

• Power World Simulator results without compensation (10)

Outline • Power World Simulator results with

compensation (11)

• Computation using MATLAB (12)

• MATAB results (13)

• Table of improvement (14)

• Another observation in simulation (15)

• Conclusion (16)

• Future work (17)

• I am thankful to… (18)

• References (19)


Abstract

• Blackout is a major concern to the power system administrator, as it can lead to the collapse of whole system or grid and this situation is arising out of maintaining the supply to the buses tackling bulk of power and is considered to be weaker and left uncompensated. In this paper, Gujarat power system network of 220kV has been considered and its power flow simulation has been carried out to identify the weak bus in case of given loading. Weak bus has been compensated with shunt compensation to keep the voltage of that particular bus regulated within a tight band and not allowed to collapsing below specified limits.


Network considered


Network parameters

• Total 11, 220kV buses showing maximum loading conditions during April-2013.

• 1 slack bus(Gandhinagar)

• 3 Generator buses(Wanakbori, Kadana, Ukai)

• 7 Load buses(Soja, Karamsad, Asoj, Godhara, Mehsana, Jambuva, Ranasan)

• Transmission lines made up of Zebra Conductors having r = 0.08 Ω/km and x = 0.402 Ω/km


Why this network?

• The considered buses in the network are to be energized first in case of blackout, so if these buses can maintain their voltage limits, then it will be easier to maintain the network alive in case of sudden load changes and an island of Gujarat grid system will survive.

• But if we can’t do the same, these buses will also go into the blackout.


Other Considerations

• Here considering maximum loadings in the April-2013, the load flow study has been run to identify the weakest buses in the network i.e. Karamsad and Jambuva.

• Once identified, proper compensation has been provided on Karamsad bus to compensate and to bring its voltage limits back in to tolerable limits.


Creating the

network

Running Load Flow

Identifying the weak

bus

Providing compensation

Computation using Power World Simulator


Power World Simulator Results without compensation

Name Nom kV PU Volt Volt (kV) Angle (Deg) Load MW Load Mvar Gen MW Gen Mvar Switched Shunts Mvar Act G Shunt MW

Gandhinagar 1 220 1.0000 220.0000 0.0000 103.0000 58.0000 263.1100 391.2200 0.0000

Wanakbori 2 220 1.0000 220.0010 19.7700 196.0000 96.0000 875.0000 386.4000 0.0000

Kadana 3 220 1.0000 220.0010 16.3400 203.0000 126.0000 240.0000 193.5300 0.0000

Ukai 4 220 1.0000 220.0010 27.0700 150.0000 87.0000 300.0000 147.3800 0.0000

Soja 5 220 0.9518 209.3860 -3.4500 123.0000 60.0000 0.0000

Karamsad 6 220 0.8700 191.4010 8.4100 88.0000 52.0000 0.0000 0.0000 0.0000 0.0000

Asoj 7 220 0.9066 199.4540 14.5200 80.0000 52.0000 0.0000

Godhra 8 220 0.9537 209.8130 15.4600 256.0000 139.0000 0.0000

Mehsana 9 220 0.9122 200.6750 -6.7700 177.0000 77.0000 0.0000

Jambuva 10 220 0.8871 195.1650 13.2100 120.0000 64.0000 0.0000

Ranasan 11 220 0.9324 205.1300 6.3800 134.0000 65.0000 0.0000

04 April 2016 NCERTE-2016 10

Power World Simulator Results with compensation

Name Nom kV PU Volt Volt (kV) Angle (Deg)Load MW Load Mvar Gen MW Gen Mvar Switched Shunts Mvar

Gandhinagar 1 220 1.0000 220.0000 0.0000 103.0000 58.0000 258.8200 348.3300

Wanakbori 2 220 1.0000 220.0000 19.2600 196.0000 96.0000 875.0000 297.2400

Kadana 3 220 1.0000 220.0000 15.8200 203.0000 126.0000 240.0000 193.5300

Ukai 4 220 1.0000 220.0000 25.9700 150.0000 87.0000 300.0000 116.6300

Soja 5 220 0.9518 209.3860 -3.4500 123.0000 60.0000

Karamsad 6 220 0.9702 213.4540 7.3500 88.0000 52.0000 0.0000 0.0000 141.21

Asoj 7 220 0.9406 206.9260 13.6800 80.0000 52.0000

Godhra 8 220 0.9537 209.8120 14.9400 256.0000 139.0000

Mehsana 9 220 0.9122 200.6750 -6.7700 177.0000 77.0000

Jambuva 10 220 0.9353 205.7750 12.2400 120.0000 64.0000

Ranasan 11 220 0.9574 210.6200 6.0700 134.0000 65.0000

04 April 2016 NCERTE-2016 11

Computation using MATLAB

• Weak bus considered PV bus injecting reactive power

• In this case Karamsad

• All generator buses considered operating at their limit

Enter the case data

• Gauss Seidel method

Run load flow

• Voltage profile improvement over Power World Simulator results

Observing the improved

voltage profile

04 April 2016 NCERTE-2016 12

MATLAB results Bus No.

Bus Name Bus type

Nominal

Voltage (kV)

Per Unit Voltage

Voltage (kV)

Angle (Degree)

Real Load (MW)

Reactive Load

(MVAR)

Real Power

Generation

(MW)

Reactive Power

Generation (MVAR)

Shunt Capacitor (MVAR)

1 Gandhinagar 1 232 1.05 231 0 103 58 0.00 0.00

2 Wanakbori 2 230 1.03 226.6 12.2805 196 96 875 656.00

3 Kadana 2 230 1.03 226.6 9.09780 203 126 240 180.00

4 Ukai 2 230 1.03 226.6 17.1885 150 87 300 225.00

5 Soja 3 220 0.9962 219.164 -3.0102 123 60

6 Karamsad 2 220 1.0000 216.678 1.0292 88 52 0 141.21 141.21

7 Asoj 3 220 0.9352 204.578 5.1492 80 52

8 Godhra 3 220 0.9888 217.536 8.2266 256 139

9 Mehsana 3 220 0.9560 210.320 -5.9675 177 77

10 Jambuva 3 220 0.9446 206.206 4.2883 120 64

11 Ranasan 3 220 1.0029 219.846 2.4452 134 65

04 April 2016 NCERTE-2016 13

Table of improvement Bus No. and Name Voltage (p.u.)

without compensation

Voltage (p.u.) with compensation in PWS

Voltage (p.u.) with compensation in MATLAB

1 Gandinagar 1.0000 1.0000 1.0500

2 Wanakbori 1.0000 1.0000 1.0300

3 Kadana 1.0000 1.0000 1.0300

4 Ukai 1.0000 1.0000 1.0300

5 Soja 0.9518 0.9518 0.9962

6 Karamsad 0.8700 0.9702 1.0000

7 Asoj 0.9066 0.9406 0.9352

8 Godhra 0.9537 0.9537 0.9888

9 Mehsana 0.9122 0.9122 0.9560

10 Jambuva 0.8871 0.9353 0.9446

11 Ranasan 0.9324 0.9574 1.0029

04 April 2016 NCERTE-2016 14

Another observation in simulation

• Slack bus is Gandhinagar instead of Wanakbori so 4 buses other than slack and generator (i.e. Asoj, Godhara, Jambuva, Ranasan) showing positive angles as they are in between load buses and generation buses.

04 April 2016 NCERTE-2016 15

Conclusion

• Gujarat island with its most heavily loaded buses considered in April 2013 with maximum loads in the season of summer.

• Weak bus Karamsad and Jambuva identified and provided required compensation at Karamsad bus but still slack bus operates at very poor power factor.

• Once the capacitor value is found out, the voltage profile is further improved in MATLAB by considering all generator buses (PV buses) operating at 0.8 power factor which is minimum required limit. So that slack bus gets little less burden of providing reactive power.

04 April 2016 NCERTE-2016 16

Future Work

• A self operating load dependent FACT device can be realized in place of fixed capacitor at weak bus.

04 April 2016 NCERTE-2016 17

I am thankful to…

• Mr. Mukund Upadhyaya (Ex. Chief Engineer, GSECL)

• Asst. Prof. Neepa Shah (Project Guide in B.E. at VGEC)

• My colleagues at B.E. level…

1. Mr. Keyur Dhagia (Hindalco)

2. Mr. Karan Gandhi (S.K. Power)

3. Mr. Arpit Kothari (Infosys)

4. Mr. Santosh Grampurohit (Infosys)

04 April 2016 NCERTE-2016 18

References

1. D.P. Kothari, I.J. Nagrath, ‘Modern Power System Analysis’, Vol. 16, Tata McGraw Hill Education Private Limited, pp. 204-213, 2003.

2. John J. Grainger, William D. Stevenson, ‘Power System Analysis’, McGraw Hill Publications, pp. 5-11 & pp. 335-342, 1994.

3. P. Srikanth, O. Rajendra, A. Yesuraj, M. Tilak, “Load Flow Analysis of IEEE 14 Bus System Using MATLAB”, International Journal of Engineering Research & Technology (IJERT), Vol. 2 Issue 5, May – 2013.

4. ‘Recovery procedure for western region’, Power System Operation Corporation Ltd.(POSCO), pp. 22-37, December – 2013,

5. Dharamjit, D.K.Tanti, “Load Flow Analysis on IEEE 30 bus System”, International Journal of Scientific and Research Publications, Volume 2, Issue 11, November 2012

04 April 2016 NCERTE-2016 19

THANK YOU

04 April 2016 NCERTE-2016 20

Documents

paper 149