Point of Common Coupling Voltage Control of a DFIG Wind Turbine Connected to Weak Grid

Control of a DFIG Wind Turbine Connected to Weak Grid

Abstract

DFIG wind turbine system is the most popular wind power generator in current market. Even though the active and reactive power output of DFIG can be controlled independently, the active power output of those wind turbines varies with wind speed. The converters in DFIG have limited capacity as a result it cannot supply usually required reactive power hence the terminal voltage of the wind turbine system connected to weak distribution grid fluctuates. So voltage regulation device is required for safe operation of power grid. This paper proposes the use of Static Synchronous Compensator (STATCOM) as a voltage regulating device at the point of common coupling to minimize terminal voltage fluctuation of the wind turbine system operating at maximum power point tracking mode (MPPT) during varying wind speed. The control scheme for DFIG wind turbine system and STATCOM is systematically developed and the effectiveness of the proposed system is verified by simulating in MATLAB/Simulink software.