A novel envelope curve modulation method for the SPWM controlled high frequency link matrix inverter

For acquiring of better quality and reducing the harmonic of the high frequency link matrix inverter-HFLMI output, a new envelope curve modulation method is discussed. The method can make the cycle duty of the front stage circuit of the HFLMI´s driving signals variable and the HFLMI can gain better output voltage and current by working with de-re -coupling SPWM modulation. The carrier wave for front stage circuit is not a DC voltage but the envelope curve output voltage of the three-phase bridge rectifier without wave filter. The cycle duty of the driving signals of the HFLMI is changed with the envelope curve of the three-phase voltage. Some details of this circuit´s operating principle and working states are analyzed, and the practicability and the feasibility of the envelope curve modulation method has been approved through PSpice simulation.