| The application of power electronics especially power diode and thyristor's application has brought a great deal of current harmonic pollution to grid, and then reduced the grid's power factor. PWM rectifier has excellent characteristics such as undistorted sinusoidal current waveform, unity power factor, so it has been used in wind powe converter, active filter, and high performance converter.Three-phase Voltage-source PWM Rectifier (VSR) is mainly studied in this thesis. The modeling of three-phase VSR, the design and simulink of the controller under different control strategy, the design of hardware and software are discussed in this thesis.Firstly using the method of average switching period an average model of three-phase VSR is set up; separate the disturbance obtained the steady-state model and small-signal model. Based on this model using simpowe modul of matlab the models of three-phase VSR system under phase and amplitude control, hysteresis current control, single hysteresis SVPWM current control, double hysteresis SVPWM current control, double cloop control are set up. The simulation results show that under different control strategy the VSR system can realize the stability of dc voltage, the sinusoidal of ac current and unity power factor of power gird. But under different control strategy the performance of VSR system has large difference. In the end, the three-phase VSR system based on TMS320LF2812 DSP is designed in this thesis with SVPWM hysteresis current control. The experimental results show that the VSR system can realize the stability of dc voltage, reduce the harmonic content and can run under unity power factor.
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