Abstract：The maximum power point tracer (MPPT) of doubly-fed wind power generation is generally based on the curve of optimal wind speed-power-wind turbine rotational speed extracted from experiment results. After long-term operation, the actual maximum power point will deviate from the original curve due to the change of system parameters, which influences the effect of maximum power point tracer. Based on analysis of the characteristic of wind turbine, the mathematical model of doubly-fed induction generator and the relation of powers and currents, this paper presents a MPPT strategy to realize the decoupling control of stator active power and stator reactive power which doesn't rely on the characteristic curve of wind turbine. The simulation and experimental results show that in the wind speed changing process the doubly-fed wind power generation system can search and trace the maximum power point automatically by using this method. Moreover, this control method is comparatively easy, reliable and has high practical value.
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2009, Vol. 24 
