两级宽输入DC/DC变换器设计与建模分析

宽输入DC/DC变换器功率器件承受电压应力变化范围大,增加了电路损耗,减小了使用寿命。两级式变换器能够减小电路中功率器件的电压应力,但控制较为复杂。此处研究了一种电流控制型双Buck级联形式的宽输入开关电源,仅对后级电路进行闭环控制,简化了控制,有效减小了电路体积。建立了电路传递函数模型,讨论了电路的稳态特性及动态特性,进行了电路的稳定性分析,并通过仿真与实验分析,证明了电路具有良好的动态性能和输出稳定性,从而验证了设计方案的可行性。

Design and Modeling of Two-stage Wide-input DC/DC Converter

Power components of wide-input DC/DC converter withstand large range of voltage stress change,which lead the circuit loss increasing and life decreasing.Two-stage converter can reduce the voltage stress of power compo-nents,but it needs complicated control method.A research on a current-controlled double-Buck cascade converter of wide-input switching power supply is done.Only the second-stage is closed-looped,which simplify control circuit and reduce the volume of circuit.The model of the transfer function is established,and the circuit’s steady state charac-teristics and the dynamic characteristics and the stability are discussed and analysed.The simulation and experimental results improve that the circuit has good dynamic performance and output stability.