Study On The Improvement Of Performance Of The Low-Voltage High-Current DC Power Supply

With the high speed development and the progress of the power source technology, the power source is used more and more widespread. It is commonly used in national defense, communication and consumer industry, however, the requirement of the power source used in these industries is more and more strictly, especially it requires that the power source possess the advantage of high efficiency and small volume and high frequency for the sake of achieving the purpose of the use under the different situation.The design process of the low-voltage and large current power supply is introduced in this paper . Its basic work process is the conversion of AC-DC-AC-DC, each part of the work process of the system is analyzed and introduced detailedly, including the electric circuit topology choice,the parameter computation and the component choice of the system, especially it has carried on the exhaustive analysis and the computation to the work process of the high frequency inverter part and the rectified output part. We have carried on the simulation analysis to the work mode of the switch by choosing the reasonable electric circuit topology and the driven control mode of the switches. This article uses the full bridge phase shifting PWM control mode which is controlled by the novel digital control mode called DSP-control. The DSP(digital signal processor) that can carry on the precise control to the work process of the switches by providing the precise control signal so that it can improve the performance of the power supply. Meanwhile the use of low on-resistance MOSFET rectifier tube to replace the traditional ordinary rectifier diodes in the rectification output can greatly reduce loss and improve the efficiency of the power supply. We have also carried on the computation and design and analysis to the transformer, the DC blocking capacitor and the resonant inductance as well as the filters inductance and the filter electric capacitor of the rectification output. Finally we carry on the simulation to the design power source and the result proves that the power supply feasible.