| As the two-quadrant converter using diode-bridge rectifier, bi-directional energy flow cannot be achieved. Moreover, in some high-power applications, the diode-bridge rectifier can arouse the serious harmonic pollution to power system. Since the three-phase PWM rectifiers are of the characteristics of sinusoidal input currents, unity power factor, steady output voltage, good dynamics and bi-directional energy flow, the design of three-phase PWM rectifier is discussed. The main contributions are made as following:The principle of the three-phase PWM rectifier is introduced in terms of the main circuit topology. The mathematics models of the three-phase PWM converter under the balanced source voltage are studied in three-dimension coordinate and d-q coordinate.The three-phase voltage-type PWM rectifier control method is discussed. Based on the model of PWM voltage rectifier in d-q synchronization reference frame, the voltage and electric current double closed-loop control method is adopted, and the unity power factor and DC voltage stability is achieved by means of three PI regulators.A simulation model is presented by means of MATLAB/Simulink. The simulation result show the PWM system can adjust the DC voltage in a certain range and make the current in AC side of the rectifier keep sinusoid. Furthermore it can create unity power factor and make power reversible.Based on the mathematics model and control model of the three-phase PWM rectifier, the hardware and software design of the digital control system using TMS320F2808 chip is provided. The feasibility of the control system was verified by relevant tests.
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