A Novel Multiphase Pulse-Width-Amplitude Modulation for Quasi Z-source Three-to-Six- Phase Direct Matrix Converter

Abstract

In order to improve the performance of electric vehicle drive system, multiphase technology is applied. For this, a three-phase quasi Z-source(QZS)network is coupled to the three-to-six phase direct matrix converter (DMC) and a new multiphase pulse-width-amplitude modulation (MP-PWAM) method is proposed. Compared with the traditional PWM method, MP-PWAM can greatly reduce the switching actions of each power device of the converter. Also, it can largely decrease the complexity of control for three-to-six phase DMC. The proposed topology of quasi Z-source three-to-six-phase direct matrix converter(QZS-SP-DMC)can effectively solve the defect of lower voltage transfer ratio of traditional matrix converter and allow the input voltage fluctuation within a certain range. Then, greatly improve the driving efficiency. The three-to-six DMC which introduced the QZS can allow the six-phase output side short circuit which defined shoot-through state. It can achieve the AC input voltage boost conversion by controlling the time of shoot-through state in one switch circle. The operating principle of QZS-SP-DMC and the MP-PWAM technique are presented in detail. The simulation is conducted in detail to verify the effectiveness of the research.