Study And Implementation Of Three Phase Voltage PWM Rectifier

Rectifier, which is also called AC/DC converter, is widely used in industry and dailylife. The traditional rectifiers of diodes and thyristors have low power factor and bringharmonic pollution to the grid. With the development of semiconductor and powerelectronics technology, PWM rectifier is more and more noticeable. PWM rectifiershave the characteristics of high power factor, controlled DC-link voltage andbidirectional power flow. It is widely used in motor control, active filtering and newenergy resources fields. Researches on PWM rectifier have been carried out in this thesis.Firstly, the principle of three-phase voltage source PWM rectifier has been analyzedin the thesis. Based on different coordinate systems, the mathematical models ofthree-phase voltage source PWM rectifier have been discussed. Also, the details of spacevector modulation(SVPWM) and the function of the switch time based on SVPWM havebeen studied.Secondly, the control technologies of three-phase voltage source PWM rectifierbased on the mathematical model have been carried out. The voltage orientedcontrol(VOC) and the predicted current control (PCC) technology have been mainlystudied in the thesis. The current control of VOC based on a fully decoupled method hasbeen proposed. Also,the design methods of the voltage loop and the current loopparameters have been studied. The implementation of the predicted current control hasbeen given out based on both the static and the rotating coordinate system. Simulationmodels of three-phase voltage source PWM rectifier based on different control methodshave been built in Matlab/Simulink with the SimPowerSystems library. The simulationresults based on both the voltage oriented control and the predicted current control havebeen analyzed.An experiment platform of three-phase voltage source PWM has been designed. The experiments of three-phase PWM rectifier have been completed. The results have beenverified that the power factor unity and the bidirectional flow of the power based on theVOC and PCC can be achieved.