Adaptive DC-link STATCOM for power system transient instability damping

Synchronous generator is the most common power source in power systems. However, when transient events such as load switching and fault occur, its mechanical input driving system may not be able to track the change of electrical power output. This results in instability of the generator, which possibly causes further failure of the overall system. This paper presents a technique to provide the system an ability to cope with transient events by improving the ability of STATCOMs that already installed in the network, in order to assist the system for damping electromechanical oscillation. The proposed idea gives the DC-link of STATCOMs the ability to react to real power variation adaptively. Simulation results illustrate that this adaptive DC-link STATCOM has a superior performance for both real and reactive power supports, compared to the ordinary ones. With this enhanced performance STATCOM inside, stability margin of the overall system will be increased.