Application of PWM Static Var Compensatorsin Increasing Power System Damping

In the long distance and large power transmission system, the vibration of power angle hardly decays. The main reason is the shortage of system damping. This paper demonstrates that PWM static var compensator (PSVC) increases the system damping. And by the use of equal area principle, the most optimal damping is tested when PSVC adopts frequency as a control signal. And then the PSVC model is presented. Finally the simulation and calculation results certify the damping characteristics of PSVC. 