Abstract
With the rapid development of communication technology, computer and electronics, DC / DC converters are more and more widely used in long-distance and data communications, computer, office automation equipment, industrial instrumentation, military, aerospace and other fields, it also demands higher technology of soft-switching .
In this paper, because of the lack of hard-switching technology, it analyzes the definition about soft-switching clearly, as well as the working principle and classification. In full-bridge converter, this paper analyzes a transformation technology which combined with PWM technology method, in other way it calls full-bridge zero-voltage zero-current switching (ZVZCS) DC / DC PWM converter. The converter can use ultra-forearm parallel capacitor, with high-frequency resonance transformer leakage inductance to achieve zero forearm switch-voltage-switching (ZVS), and at the same time achieving the function zero-current switching (ZVS).
In this thesis, the main circuit of the entire design process is using phase-shifting to control the circuit while using UC3879 to achieve integrated circuits. Besides, it also tell the difference of UC3875 and UC3879 and set out to do. In addition, by setting the related parameters to better achieve the experimental requirements ,and using PSIM to simulate the circuit.