Stability Enhancement of DFIG-Based Variable Speed Wind Turbine With a Crowbar by FACTS Device as Per Grid Requirement

Abstract

A crowbar protection switch is normally considered to protect the power converter of doubly fed induction generator (DFIG) during grid fault. However, the crowbar protection has some adverse effects on the operation of DFIG as to deteriorate the independent controllability of real and reactive powers. This paper investigates the effect of connecting FACTS (Flexible AC Transmission System) device such as a STATCOM (Static Synchronous Compensator) to the point of common coupling (PCC) of a wind farm composed of DFIG. Simulation results in power system computer aided design/electromagnetic transient including DC (PSCAD/EMTDC) show that a FACTS device can effectively enhance the performance of the DFIG, when it is disconnected by the crowbar switch during grid fault by providing additional reactive power to the system, thus improving the voltage instability performance of the DFIG and the wind farm as well.