单电感双输出CCM Buck变换器输出交叉影响分析

Cross-regulation Analysis of SIDO CCM Buck Converters

以工作于电感电流连续导电模式(continuous conduction mode,CM)的单电感双输出(single-inductor dual-output,IDO)Buck变换器为研究对象,采用时间平均等效电路方法,给出SIDO CCM Buck变换器的直流电压增益及系统的输出/控制、交叉影响、耦合等传递函数。在此基础上,得到一种分析SIDO CCM Buck变换器交叉影响的功率级小信号模型。论文建立电压控制SIDO CCM Buck变换器的闭环小信号模型,分析变换器两路输出负载变化对两路输出支路的交叉影响。最后,通过仿真和实验结果验证理论分析的正确性。

As the single-inductor dual-output （SIDO） Buck converter in the continuous conduction mode （CCM） for the study, the expressions for DC voltage gains and control to the output transfer function, cross-regulation transfer function and cross-coupled transfer function of the system are derived by the time averaging equivalent circuit approach. Based on this, a power stage small signal model to analyze the cross-regulation of SIDO CCM Buck converters was proposed. With the voltage-feedback controlled SIDO CCM Buck converter as an example, the closed small signal model was established and the cross-regulation was analyzed with changing loads. Finally, the simulation and experiment results show that the theoretical analysis is reliable.