DESIGN OF REACTIVE CURRENT CONTROLLER FOR STATCOM USING GA AND PSO

Abstract

The STATic synchronous COMpensator (STATCOM) is a voltage source converter (VSC) based FACTS controller. It is a shunt connected FACTS controller and most suitable in long transmission line for regulating voltage, improving stability and enhancing power transfer capability. STATCOM with PI controller based reactive current control experiences oscillatory instability in inductive mode. The incorporation of nonlinear state variable feedback with PI controller can overcome the oscillatory instability predicted in the inductive operation mode of STATCOM. However, the response or performance of the STATCOM depends primarily on the parameters of controller. This paper presents optimization of controller parameters based on Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), and the results are compared. The performance of the designed controller is evaluated by transient simulation. The two methods have good ability in searching global optimum, and it is observed that GA outperforms PSO, and efficient in searching global minimum, fast convergence, less computational time and guarantees global or near global minimum with less number of function evaluations. The transient response of STATCOM with optimized controller parameters for large deviation (step change) in reactive current reference shows excellent response. The design of controller and eigenvalue analysis are based on D-Q model,and the transient simulation is based on both D-Q and three phase (considers switching a