Output power smoothing of PMSG-based wind energy conversion system

This paper presents a control method for output power smoothing of a wind energy conversion system (WECS) with a permanent magnet synchronous generator (PMSG) using the inertia of wind turbine and pitch control. The WECS used in this paper adopts an AC-DC-AC method with voltage-source converters (VSC). The generator-side converter controls the generator torque of the PMSG, while the grid-side inverter controls the DC-link voltage and the grid voltage, respectively. In the generator-side converter, the generator torque command is determined by using a fuzzy logic. By means of the proposed method, the generator torque is smoothed and the kinetic energy can be utilized to smooth the output power fluctuations of the PMSG. The effectiveness of the proposed method is validated by numerical simulations.