Dynamic Voltage Control Effect of Multiple SVCs with Coordinated Slops Setting

The static var compensators (SVCs) widely applied in power system have remarkable effect on fast voltage control and var compensation, and help to improve voltage stability and transmission capability. Their control function is decided by the reference voltage, the slope, and the time constant. Since there are possibly multiple SVCs closely located, the control parameters should be carefully set to fully utilize the operation margins while not violating the control limits. In this paper, the effect of the slope on reactive power output is analyzed. The two SVCs are reasonably coordinated by adjusting their different slopes in order not to violate their limits. The influence on the selected slopes of heavy load is discussed. The numerical results on the WCSS 9-bus test system are finally provided to validate the control effect.