## Main Article Content

## Abstract

This paper investigates the effect of typical load model parameters on the static var compensator (SVC) stabilizers tuning. A proportional-Integral (PI) type stabilizer is considered and its gain-settings are tuned using the pole-placement technique to improve the damping of power systems. Tuning of SVC stabilizers (damping controllers) traditionally assumes that the system loads are voltage dependent with fixed parameters. However, the load parameters are generally uncertain. This uncertain behavior of the load parameters can de-tune the gains of the stabilizer; consequently the SVC stabilizer with fixed gain-settings can be adequate for some load parameters but contrarily can reduce system damping and contribute to system instability with loads having other parameters. The effect of typical load model parameters on the tuning gains of the SVC PI stabilizer is examined and it is found the load parameters have a considerable influence on the tuning gains. The time domain simulations performed on the system show that the SVC stabilizer tuned at fixed load parameters reduce the system damping under other load parameters and could lead system instability.

## Keywords

## Article Details

*How to Cite*

*The Journal of Engineering Research [TJER]*,

*5*(1), 71–78. https://doi.org/10.24200/tjer.vol5iss1pp71-78

* * References

- Alden, R.T.H. and Zein El-Din, H.M., 1976, "Effect of Load Characteristics on Power System Dynamic Stability," IEEE Trans on Power App. and Syst. Vol. PAS-95, pp. 1762-1768.
- Berg, G.J., 1973, "Power-System Load Representation," Proc. IEE, Vol. 120(3), pp. 344-348.
- Cheng, C.H. and Hsu, Y.Y., 1992, "Damping of Generator Oscillations Using an Adaptive Static VAR Compensator," IEEE Trans. on Power Systems, Vol. 7(2), pp. 718-725.
- Choudhry, M.A, Emarah, A.S., Ellithy, K.A. and Galanos, G.D., 1986, "Stability Analysis of a Modulated AC/DC System Using the Eigenvalue Sensitivity Approach", IEEE Transactions on Power Systems, Vol. PWRS-1(2), pp.128-137.
- Choudhry, M.A., Reza, M.A. and Ellithy, K.A., 1990, "Design of a Robust Modulation Controller over a Wide Range of Load Characteristics for AC/DC Systems," IEEE Trans. on Power Systems, Vol. 5(1), pp. 212-218.
- Concordia, C. and Ihara, S., 1982, "Load Representation in Power System Stability Studies," IEEE Trans. on Power App. And Syst, Vol. PAS-101, pp. 969-977.
- Craven, R.H. and Micheal, M.R., 1983, "Load Representation in the Dynamic Simulation of the Queensland Power System", J. of Electrical and Electronics Engineering, Vol. 3(1), pp. 1-7.
- Ellithy, K.A., 1997, "Effect of Voltage Dependent Load Models on Power System Stabilizers Design," Fifth Int. Middle East Power System Conference (MEPCON' 05), Vol. 1, pp. 370-376.
- Ellithy, K.A. and Choudhry, M.A., 1989, "Effect of Load Models on AC/DC System Stability and Modulation Control Design," IEEE Trans. on Power Systems, Vol. 4, pp. 411-418.
- Ellithy, K.A. Al-Alawi, S.M. and Zein El-Din, H.M., 1997, "Tuning Power System Stabilizers Over a Wide Range of Load Models Using an Artificial Neural Network," J. of Engineering and Applied Science, College of Engineering, Cairo University, Vol. 44(2), pp. 389-406.
- El-Metwally, K. and Ellithy, K., 2003, "A Self Organizing Fuzzy Controller for SVC Stabilizers Design in the Presence of Load Characteristics Uncertainty", IEEE International Middle East Power Conference (MEPCON 2003), Vol. 1, pp. 31-37.
- El-Saady, G., El-Sadek, M. and Abo-Elsaoud, M., 1998, "Fuzzy Adaptive Model Reference Approach-Based Power System Static VAR Stabilizer", Electric Power System Research, Vol. 45, pp. 1-11.
- Fang, D.Z., yang, X., Chung, T.S. and Wong, K.P., 2004, "Adaptive Fuzzy-Logic SVC Damping Controller Using Strategy of Oscillation Energy Descent" IEEE Trans. on Power Systems, Vol. 19(3), pp. 1414-1421.
- Farsangi, M.M., Song, Y.H. and Lee, K.Y., 2004, "Choice of FACTS Device Control Inputs for Damping
- Interarea Oscillations," IEEE Trans. On Power Systems, Vol. 19(2), pp. 1135-1143.
- Hammad, A.E. and El-Sadek, M., 1984, "Application of a Thyristor Controlled Var Compensator for Damping Subsynchronous Oscillations in Power Systems," IEEE Trans. Power App. And Syst, Vol. PAS-103, pp. 198-212.
- Hamoud, R.M., Irvani, M.R. and Hackam, R., 1987, "Coordinated Static Var Compensators and Power System Stabilizers for Damping Power System Oscillations," Presented at Power Winter Meeting, Paper '87, Vol. WM 045(8), pp. 1059-1067.
- Hsu, Y.Y. and Wu, C.J., 1988, "Adaptive Control of a Synchronous Machine Using the Auto-Searching Method", IEEE Trans. on Power Systems, Vol. 3(4),pp. 1434-1439.
- IEEE Special Stability Controls Working Group 1994, "Static Var Compensator Models for Power Flow and Dynamic Performance Simulation," IEEE Trans. on Power Systems, Vol. 9(1), pp. 229-239.
- IEEE Task Force on Load Representation for Dynamic Performance, 1995, "Bibliography On Load Models For Power Flow and Dynamic Performance Simulation," IEEE Trans. On Power System, Vol. 10(1), pp. 524-538.
- Langevin, M. and Auriol, P., 1986, "Load Response to Voltage Variations and Dynamic Stability," IEEE Trans. on Power Systems, Vol. PWRS-1(4), pp. 112- 118.
- Lee, S. and Liu, C.C., 1994, "An Adaptive Output Feedback Static VAR Controller for the Damping of Generator Oscillations," Electric Power System Research, Vol. 29, pp. 9-16.
- Mauricio, W. and Semlyen, A., 1972, "Effect of Load Characteristics on the Dynamic Stability of Power Systems," IEEE Trans. Power App. And Syte, Vol. PAS-91, pp. 2295-2304.
- Milianovic, J.V. and Hiskens, I.A., 1995, "Effect of Load Dynamic on Power System Damping," IEEE Trans. on Power Systems, Vol. 10(2), pp. 1022-1028.
- Ohyama, T., et al. 1985, "Voltage Dependence of Composite Load in Power Systems," IEEE Trans. on Power App. and Syst., Vol. PAS-104(11), pp. 3064- 3073.
- Xu, W. and Mansour, Y., 1994, "Voltage Stability Analysis Using Generic Dynamic Load Models Load," IEEE Trans. on Power Systems, Vol. 9(1), pp. 479-493.
- Xu, W., Vaahedi, E. Mansour, Y. and Tamby, J., 1997, "Voltage Stability Load Parameter Determination from Field Tests on B.C. Hydro's System," IEEE Trans. on Power Systems, Vol. 12(3), pp. 1290-97.
- Yu, X., Khammash, M. and Vittal, V., 2001, "Robust Design of Damping Controller for Static Compensator in Power Systems," IEEE Trans. on Power Systems, Vol. 16(3), pp. 456-462.
- Zein El-Din, H.M. and Price, W.W., 1988, "Dynamic Load Modeling in Large Scale Stability Studies", IEEE Trans. on Power Systems, Vol. 3(3), pp. 1039-1045.

#### References

Alden, R.T.H. and Zein El-Din, H.M., 1976, "Effect of Load Characteristics on Power System Dynamic Stability," IEEE Trans on Power App. and Syst. Vol. PAS-95, pp. 1762-1768.

Berg, G.J., 1973, "Power-System Load Representation," Proc. IEE, Vol. 120(3), pp. 344-348.

Cheng, C.H. and Hsu, Y.Y., 1992, "Damping of Generator Oscillations Using an Adaptive Static VAR Compensator," IEEE Trans. on Power Systems, Vol. 7(2), pp. 718-725.

Choudhry, M.A, Emarah, A.S., Ellithy, K.A. and Galanos, G.D., 1986, "Stability Analysis of a Modulated AC/DC System Using the Eigenvalue Sensitivity Approach", IEEE Transactions on Power Systems, Vol. PWRS-1(2), pp.128-137.

Choudhry, M.A., Reza, M.A. and Ellithy, K.A., 1990, "Design of a Robust Modulation Controller over a Wide Range of Load Characteristics for AC/DC Systems," IEEE Trans. on Power Systems, Vol. 5(1), pp. 212-218.

Concordia, C. and Ihara, S., 1982, "Load Representation in Power System Stability Studies," IEEE Trans. on Power App. And Syst, Vol. PAS-101, pp. 969-977.

Craven, R.H. and Micheal, M.R., 1983, "Load Representation in the Dynamic Simulation of the Queensland Power System", J. of Electrical and Electronics Engineering, Vol. 3(1), pp. 1-7.

Ellithy, K.A., 1997, "Effect of Voltage Dependent Load Models on Power System Stabilizers Design," Fifth Int. Middle East Power System Conference (MEPCON' 05), Vol. 1, pp. 370-376.

Ellithy, K.A. and Choudhry, M.A., 1989, "Effect of Load Models on AC/DC System Stability and Modulation Control Design," IEEE Trans. on Power Systems, Vol. 4, pp. 411-418.

Ellithy, K.A. Al-Alawi, S.M. and Zein El-Din, H.M., 1997, "Tuning Power System Stabilizers Over a Wide Range of Load Models Using an Artificial Neural Network," J. of Engineering and Applied Science, College of Engineering, Cairo University, Vol. 44(2), pp. 389-406.

El-Metwally, K. and Ellithy, K., 2003, "A Self Organizing Fuzzy Controller for SVC Stabilizers Design in the Presence of Load Characteristics Uncertainty", IEEE International Middle East Power Conference (MEPCON 2003), Vol. 1, pp. 31-37.

El-Saady, G., El-Sadek, M. and Abo-Elsaoud, M., 1998, "Fuzzy Adaptive Model Reference Approach-Based Power System Static VAR Stabilizer", Electric Power System Research, Vol. 45, pp. 1-11.

Fang, D.Z., yang, X., Chung, T.S. and Wong, K.P., 2004, "Adaptive Fuzzy-Logic SVC Damping Controller Using Strategy of Oscillation Energy Descent" IEEE Trans. on Power Systems, Vol. 19(3), pp. 1414-1421.

Farsangi, M.M., Song, Y.H. and Lee, K.Y., 2004, "Choice of FACTS Device Control Inputs for Damping

Interarea Oscillations," IEEE Trans. On Power Systems, Vol. 19(2), pp. 1135-1143.

Hammad, A.E. and El-Sadek, M., 1984, "Application of a Thyristor Controlled Var Compensator for Damping Subsynchronous Oscillations in Power Systems," IEEE Trans. Power App. And Syst, Vol. PAS-103, pp. 198-212.

Hamoud, R.M., Irvani, M.R. and Hackam, R., 1987, "Coordinated Static Var Compensators and Power System Stabilizers for Damping Power System Oscillations," Presented at Power Winter Meeting, Paper '87, Vol. WM 045(8), pp. 1059-1067.

Hsu, Y.Y. and Wu, C.J., 1988, "Adaptive Control of a Synchronous Machine Using the Auto-Searching Method", IEEE Trans. on Power Systems, Vol. 3(4),pp. 1434-1439.

IEEE Special Stability Controls Working Group 1994, "Static Var Compensator Models for Power Flow and Dynamic Performance Simulation," IEEE Trans. on Power Systems, Vol. 9(1), pp. 229-239.

IEEE Task Force on Load Representation for Dynamic Performance, 1995, "Bibliography On Load Models For Power Flow and Dynamic Performance Simulation," IEEE Trans. On Power System, Vol. 10(1), pp. 524-538.

Langevin, M. and Auriol, P., 1986, "Load Response to Voltage Variations and Dynamic Stability," IEEE Trans. on Power Systems, Vol. PWRS-1(4), pp. 112- 118.

Lee, S. and Liu, C.C., 1994, "An Adaptive Output Feedback Static VAR Controller for the Damping of Generator Oscillations," Electric Power System Research, Vol. 29, pp. 9-16.

Mauricio, W. and Semlyen, A., 1972, "Effect of Load Characteristics on the Dynamic Stability of Power Systems," IEEE Trans. Power App. And Syte, Vol. PAS-91, pp. 2295-2304.

Milianovic, J.V. and Hiskens, I.A., 1995, "Effect of Load Dynamic on Power System Damping," IEEE Trans. on Power Systems, Vol. 10(2), pp. 1022-1028.

Ohyama, T., et al. 1985, "Voltage Dependence of Composite Load in Power Systems," IEEE Trans. on Power App. and Syst., Vol. PAS-104(11), pp. 3064- 3073.

Xu, W. and Mansour, Y., 1994, "Voltage Stability Analysis Using Generic Dynamic Load Models Load," IEEE Trans. on Power Systems, Vol. 9(1), pp. 479-493.

Xu, W., Vaahedi, E. Mansour, Y. and Tamby, J., 1997, "Voltage Stability Load Parameter Determination from Field Tests on B.C. Hydro's System," IEEE Trans. on Power Systems, Vol. 12(3), pp. 1290-97.

Yu, X., Khammash, M. and Vittal, V., 2001, "Robust Design of Damping Controller for Static Compensator in Power Systems," IEEE Trans. on Power Systems, Vol. 16(3), pp. 456-462.

Zein El-Din, H.M. and Price, W.W., 1988, "Dynamic Load Modeling in Large Scale Stability Studies", IEEE Trans. on Power Systems, Vol. 3(3), pp. 1039-1045.