大功率移相全桥变换器变压器副边全波整流电路寄生振荡研究

Research on Parasitic Oscillation of Transformer Secondary Side Full- wave Rectifier Circuit in High Power Phase- shifted Full Bridge Converter

针对大功率低压大电流应用的移相全桥变换器的变压器副边全波整流二极管上的寄生振荡问题，建立了一种包含高频变压器漏感、高频变压器副边整流二极管寄生电容以及RC吸收电路等的等效电路模型。利用PSIM软件进行仿真分析，分析了RC吸收参数的影响并提出了一种参数整定方法。另外，对实际RC吸收电路中吸收电阻的寄生电感所引起高频振荡的问题也进行了分析，给出了吸收电阻选择的建议。最后，在21kW的大功率移相全桥变换器实验平台上进行了相关实验，验证了苓文所提出的参数整定方法的有效性。

Aiming at the parasitic oscillation in the full wave rectifier diode of a phase shift full bridge converter with high power low voltage and large current, an equal effect circuit model including the leakage inductance of high frequency transformer,the parasitic capacitance of the high frequency transformer secondary rectifier diode and the RC absorption circuit is established in this paper. Through the simulation analysis of PSIM software, the influence of RC absorption parameters is analyzed, and a parameter tuning method is put forward. In addition, the high frequency oscillation caused by the parasitic inductance of the absorption resistance in the actual RC absorption circuit is also analyzed, and the suggestion of the selection of the absorption resistance is given. Finally, relevant experiments were carried out on the 21kW high power phase shifted full bridge converter experimental platform, and the effectiveness of the proposed parameter tuning method was verified.