交错控制双输入Buck变换器的工作模式及输出纹波电压分析

Analysis of Operation Mode and Output Ripple Voltage of Interleaved-Ccontrol Double-Input Buck Converters

针对两路输入电压大小不等而导致交错控制双输入Buck变换器工作模式复杂、参数设计困难的问题,将变换器的两路输入电压分3种情况进行分析和讨论,并且建立了变换器工作于连续导电模式(CCM)和不连续导电模式(DCM)的临界负载、电感电流和输出纹波电压数学模型。研究发现,变换器的临界负载随两路输入电压压差的减小而增大,电感电流纹波及输出纹波电压随两路输入电压压差的减小而减小;当两路输入电压相等时,变换器的临界负载达到最大,电感电流纹波及输出纹波电压达到最小。最后搭建了双输入Buck变换器实验平台,并通过给定的3组输入电压进行实验分析,实验结果验证了变换器的工作模式以及输出纹波电压数学模型的正确性。研究结果可为交错控制方式的双输入Buck变换器的参数设计提供理论依据。

In order to solve the problem of complex operation mode and difficult parameter design of the interleaved-control double-input Buck converter due to the difference of the two input voltages,three cases of the two input voltages of the converter are analyzed and discussed.Mathematical models of critical load,inductance current and output ripple voltage of the converter operating in continuous conduction mode(CCM)and discontinuous conduction mode(DCM)are established.It is found that the critical load of the converter increases as the difference between the two input voltages decreases,and the inductor current ripple and output ripple voltages decrease as the voltage difference between the two input voltages decreases.When the two input voltages are equal,the critical load of the converter reaches the maximum,and the inductor current ripple and output ripple voltages reach the minimum.Finally,an experimental platform for double-input Buck converter is built,and three groups of different input voltages are given for experimental study.The experimental results verify the correctness of the operation mode of the converter and the mathematical models of the output ripple voltage.The research results provide a theoretical basis for the parameter optimization design of the double-input Buck converter with interleaved control.