Full Capability of Harmonic Current Mitigation for a Wind Energy System

摘要

In this article, a novel control strategy is proposed to exploit the full capability, in terms of active filtering, of a wind energy conversion system based on a doubly fed induction generator. To achieve control of the wind energy conversion system, the rotor of the doubly fed induction generator is connected to the grid through a back-to-back pulse-width modulation converter. The proposed algorithm is applied to the rotor-side converter to ensure simultaneous active power production and power quality improvement. Depending on the nominal rotor-side converter power, the control strategy manages the wind energy conversion system function priorities between active power production, reactive power compensation, and current active-selective filtering without any system overrating. This study's main goal is to exploit the full capability of the rotor-side converter in terms of active and selective filtering. In fact, it is proposed to eliminate the whole harmonic currents if possible, or to compensate the fifth and the seventh predominant components and a part of the rest of the harmonic currents. Otherwise, one may filter a part of these two predominant harmonics in such a way that the rotor-side converter operates at its full capacitance. Simulation results demonstrate the effectiveness of the proposed strategy.