Study Of MOSFET Application And Design Of Main Circuit

This article is based on CFUBMSIP technics. Firstly, ascertain the ZVS PWM of current doubler rectifier as the power supply main circuit. It can realize the zero switches in a wider load range. Meanwhile, designed parameter of the main circuit and simulated. Secondly, because fruquency and power ,select power MOSFET as the main device. Studied the drive method ,designed proper drive circuit for MOSFET. Thirdly, the methods of paralleling MOSFETs are presented to enlarge output power of the power supply. When MOSFET paralleled, due to tolerances of semiconductors, gate-drive, and mechanical parameters, the total load current is not shared equally between paralleled MOSFETs . The methods to achieving balanced current are presented and simulated in this paper. Finally, the snubbers are designed to compress the switching voltage transient. When MOSFET is abruptly turned off, trapped energy in the circuit stray inductance is dissipated in MOSFET, causing a voltage overshoot and damaging MOSFET. This paper analyzes the principle of the snubber and discusses the impact of the parameters of the snubber on voltage overshoot. Under different number of snubber circuit, switch frequency, characteristic of load and circuit parameters, the performance of full-bridge inverter is simulated.