Power system stabilizing control using variable series capacitor based on H∞ control theory considering AVR and governor

With the progress of power electronics, power system control systems using flexible AC transmission systems (FACTS) have been eagerly studied. Variable series capacitor (VSrC) for power system stabilization control is a typical application. For effective control of VSrC, the optimal control theory has been applied. However, H^∞ control theory is expected to be more robust than the optimal control, because there are uncertain parameter changes and various disturbances in power systems. In this paper, the authors apply H^∞ control theory to the power system stabilization control including the characteristics of conventional equipment such as AVR and governor. VSrC equipment is integrated into the power system stabilization control and its effect of enhancing stabilization was investigated. Numerical analyses have been done on a power system model to demonstrate the effectiveness of the proposed control scheme. Encouraging results have been obtained for H^∞ control of VSrC through the simulation