Research On Three-phase High Power Factor PWM Converter

This thesis analyses and studies the three-phase voltage source and three-phase current source high power factor PWM converter. Firstly, the mathematical model, the operating principle and the method of control of the three-phase voltage source converter are explained. On the basis of this, the hysteresis current controller (HCC) and the space vector modulation (SVM), as the popular techniques at present, are combined and applied to the control of three-phase voltage source high power factor PWM rectifier. This technique reduces significantly the number of switching and the switching loss. The validity of this technique is proved by MATLAB simulation. Secondly, the operating principle and the mathematical model and the control method about the three-phase current source PWM converter are analysed .The generation of the PWM signal and its difference from voltage source converter's are introduced emphatically. On the basis of this, the main circuit of three-phase current source converter is applied to the design of battery discharge circuit. The discharge circuit carries out the discharge with constant current, at the same time the discharge energy is delivered to power line. The feasibility of the circuit is verified by the simulation basis on MATLAB.