Smoothing of Wind Power Fluctuations for Permanent Magnet Synchronous Generator-Based Wind Energy Conversion System and Fault Ride-through Consideration

Abstract

Due to the increment of penetration level of wind power generation, output power fluctuation is one of the most important issue's that can destabilize the power system operation. This article mainly deals with the smoothing of the output power fluctuations of a wind energy conversion system based permanent magnet synchronous generator and fault ride-through enhancement during a grid fault. The concerned wind energy conversion system based permanent magnet synchronous generator adopts an AC-DC-AC converter system. The proposed control method limits the wind energy conversion system output power by adjusting the pitch angle of the wind turbine blades when wind speed is above the rated wind speed. In the grid-side converter, a fuzzy logic controller is used to determine the torque reference for which the kinetic energy stored by the inertia of wind turbine can smooth the output power fluctuations of the permanent magnet synchronous generator. Also, the DC-link voltage, controlled by the grid-side inverter, is adjusted in accordance with the output power fluctuations of the permanent magnet synchronous generator using a voltage smoothing index. Moreover, in this aticle, the proposed method ensures that the wind turbine stays operational during grid faults and provides fast restoration once the fault is cleared. To show the effectiveness of the proposed method, simulations under different conditions have been performed by using MATLAB/Simulink® (The Math Works, Natick, MA, USA).