Fuzzy-logic-based maximum power point tracking strategy for Pmsg variable-speed wind turbine generation systems

In order to achieve maximum power point tracking (MPPT) for wind power generation systems, the rotating speed of wind turbines should be adjusted in the real time according to wind speeds. However, fast wind speed variations and heavy inertia compromise the MPPT control of a wind turbine. In this paper, a fuzzy-logic based MPPT strategy is proposed for PMSG variable speed wind turbine generation systems. The proposed MPPT strategy adopts a hill climbing searching (HCS) method, and thus is independent of the turbine and generator characteristics. The MPPT strategy locates the system operation points along the maximum power curves based on the inverter dc-link voltage, thus avoiding the generator speed detection. Two control loops are designed for the MPPT control. Both simulation and field tests have been conducted to validate the performance of the proposed MPPT strategy, and all results have verified the effectiveness of the MPPT strategy.