A novel fuzzy integral sliding mode current control strategy for maximizing wind power extraction and eliminating voltage harmonics

A novel fuzzy integral sliding mode current control strategy is proposed to extract the maximum wind power and eliminate the high-order voltage harmonics at the generator side for a direct-driven wind energy system. In this control strategy, a fuzzy logic generator is employed to derive the peak power points based on the variations of measured DC-side voltage and current. An integral sliding mode current controller is then designed in this control strategy to track the peak power points. A harmonic compensator is also built inside the fuzzy logic generator for minimizing the voltage harmonics. Major issues in the design and implementation of the control strategy such as detailed design procedure and stability condition have been presented. Comparative experimental results have demonstrated the achievable significant improvements on the maximum power extraction and harmonic elimination by using the proposed control strategy as compared with a conventional control method.