Optimal Pulse Density Modulation for Voltage Source High Frequency Inverter with Transformer-Coupled Load

Abstract

For the voltage source inverter (VSI) controlled by a pulse density modulation (PDM) and having a load matching transformer, a method to obtain the optimal pattern of pulse sequence is discussed, with which the output current ripple is minimized and the transformer saturation can be avoided. The flux saturation problems in the transformer are investigated and the method of determination for the optimal pattern is explained. It is believed that the proposed technique is useful for a practical application such as the high frequency power supply of induction heating system.