Abstract
At present, the switching power supply developed high frequency, high reliability, low energy consumption, low noise, interference and modular direction. That is to develop the inverter power source controlled by microcomputer which adopts soft-switches .
This researching task is put forward on the base of discussing the characteristics and virtues of the welding inverter. The phase-shift chip UC3875 is adopted phase-shift pulse width modulate. The design about high frequency transformer is given .The amplified circuit and the commuted circuit are designed. The paper mostly researches and designs the soft-switch control system.
Secondly, the control circuit, the protect circuit of the power supply are analyzed and designed. Its control circuit is centered on UC3875, uses a control that based regulation to realize the function is composed of analog of voltage-stabilization and current-limited.
In addition, the safeguard circuit that mainly consists of over current, over heat, over voltage and circuit are studied and designed in the paper.
And the circuit is simulated by the SABER, Simulation results show that the design is correct.