Study On High Frequency High-current DC Switching Paralleled Module Basic Technology

With the progress of industrial production, industries need more stringent high-current converter device. The traditional DC converter usd power frequency rectification program, so there is a large mass and volume, lack of flexibility, low power factor, can not satisfy the needs of the modern industry. In contrast switching power supply with digital control are reliable, stable, flexible, and easy to expand so gradually accepted by the industry. As single power electronic devices limit the total power output. So multiple modules in parallel outputs become the mainstream of development, current sharing problems becomes the key technology in multiple modules in parallel working to achieve large power output.In this paper, a brief review of the high-frequency switching power supply development is made. Analyze the important role of phase-shifted full-bridge soft-switching technology in improving power factor, reducing device dissipation, extending device lifetime. Discusses the working principle of high-frequency switching power supply, analyzed and compared current sharing methods in multiple modules in parallel. To design a high-current switching DC power modules can be connected in parallel, including the rectifier bridge rectifier, the rectifier bridge rectifier, IGBT inverter bridge, high-frequency transformer, output full-wave rectifier, DC output filter. This design of switching power supply system with DSP chip as the core control device to protect the power module, produce the drive phase-shifted full-bridge PWM pulse with fuzzy PID algorithm, monitor power modules and other real-time status. In order to expand the output current between the parallel modules the maximum current sharing method are used.Simulation and some experimental results show that the thesis of the study design high current switching power supply achieve a high power factor, the output voltage reaches a stable. DSP as the core control device achieve voltage adjustable. The maximum current sharing method can ensure the current output is not very different when multi modules in parallel.Through the paper make contribute to the high current in parallel soft switching power supply analysis, design and modeling. For the application of full bridge phase shifting soft switch circuit laid a foundation.