Mitigation of disturbances in DFIG-based wind farm connected to weak distribution system using STATCOM

Abstract

DFIG (Doubly Fed Induction Generator) based wind farm is gaining popularity these days because of its inherent advantages like variable speed operation and independent controllability of active and reactive power over conventional Induction Generators. When interconnected into power grid, it brings voltage stability problems during grid-side disturbances. So integration of DFIG-based wind farm to power grid, especially to weak distribution system is major concern for power system engineers today with the recent grid code requirements. This paper examines the use of Static Synchronous Compensator (STATCOM) as a dynamic reactive power compensator at the point of common coupling to maintain stable voltage by protecting DFIG-based wind farm interconnected to weak distribution system from going offline during and after the disturbances. The developed system is simulated in MATLAB/Simulink and the results show that STATCOM mitigates the effects of transient disturbances viz., three phase fault, step load change, voltage swelling and sagging in the system and hence improves the stability and performance of wind farm.