Research And Design Of Resonant Soft-switching Power Supply Base On Self-sustained Oscillation Phase-shift Control

Switching power supply is widely used in the production of social life according onthe variety of demand for energy in different transformations. Due to its high efficiencycan bring huge economic benefits, and thus has a high value in engineering research anddesign of switching power supply. Based on self-sustained oscillation phase shift control,the resonant soft-switching power supply of1kW is designed.In this paper, DC/DC converter structure is adopted in the main circuit topology ofthe researched switching power supply, posed by the primary full-bridge LLC seriesresonant circuit and a secondary full bridgerectifier circuit filter. For the main work ofwaveforms in different switching mode of LLC full bridge series resonant circuit，anequivalent circuit model of the resonant circuit is created according on the fundamentalapproximation，and the input and output voltage conversion characteristics and operatingcharacteristics of the anti-load short of the full-bridge LLC series resonant converter isanalyzed，besides the work area of converter is determined，furthermore the detaileddesign of main circuit parameter is completed. In pace of self-sustained oscillation phaseshift control bright the system coverage, the hardware and software in the control systemof the designed switching power supply is completed, and the optimization design ofmagnetic component in the system are realized. The soft-switching problem of thedesigned switching power supply is resolved under any load conditions, and achieve highpower operation when work in steady-state. The designed power supply is simulated andanalyzed with the PSPICE9.2simulation software, come to power system is designedwith good dynamic response and steady state performance, the rationality of power supplydesign is verified.Finally, the main circuit experiment platform is built to the design of switching powersupply. The digital signal processor TMS320F2812of the TI company was used as thecontrol chip with the C language program of the DSP was finished, even the experiment ofthe resonant soft switching power supply system based on self sustained oscillation phaseshift control was completed, and the experiment results confirmed the rationality of the schemeand come to the design request.