Stability enhancement of a grid connected wind farm by using STATCOM

Abstract

As wind power is the fastest growing renewable energy, it is essential to determine problems associated with maintaining a stable power system when it is connected to grid. In this article a simple strategy is described to stabilize a grid-connected wind farm by controlling reactive power and minimizing voltage fluctuation using a simple 6-pulse Static Synchronous Compensator (STATCOM). The STATCOM is controlled by using voltage control loop with PI controller and Pulse Width Modulation with carrier frequency of 9 times fundamental and varying dc voltage. This paper also presents a comparative study of stabilizing a wind farm using this STATCOM or using only a capacitor bank during wind speed change. Simulation results show that the wind farm could be more effectively stabilized by using STATCOM. The choice of this study is justified by simulation in PSCAD/EMTDC program.