Direct Power Control of a PWM Rectifier Fed Autonomous Induction Generator for Wind Energy Applications

In this paper, a control strategy for a stand alone induction generator (IG) driven by a variable speed wind turbine for use in remote area power supply is presented. The IG is excited simultaneously by a capacitor bank and a PWM rectifier. During the voltage build up process, there is a variation in the flux linkage of the induction generator. The variation of the magnetising inductance is taken into account due to saturation of the core. To achieve the main goal of the control system, which consists to keeping the DC link voltage constant regardless of the magnitude of the load power, a direct power control (DPC) technique is proposed. In DPC approach, the converter switching states are selected directly by a switching table based on the instantaneous errors between the controlled and estimated values of active and reactive power.The simulation calculation was achieved using MATLAB®-SIMULINK® package and results are presented to support the theoretical discussion.