Adjustable frequency and current high frequency quasi-resonant inverter with series connected power MOSFET for induction heating

In this paper, the performance and experimental results of adjustable frequency and current high frequency quasi-resonant inverter is described. This inverter circuit includes the first resonant capacitor and that of the second resonant capacitor with one-way short-circuit switch and can output the variable frequency from 160kHz to 400kHz by using power Metal Oxide Semiconductor Field Effect Transistors (MOSFETs). Synthetic series capacitance is varied by manipulating the switch and then the resonant frequency can be adjusted. The power MOSFET has the disadvantage of withstand voltage and current. To solve this problem by the methods of connected switching devices to series, and using output transformer. Voltage across the series connected power MOSFETs are balanced by magnetically coupling all gate lines using a simple two-winding transformer.