用于单电感双输出Buck变换器的PCPV控制方案

为减小工作于连续导电模式(continue conduction mode,CCM)的单电感双输出(single-inductor dual-output,SIDO)Buck变换器的输出交叉影响,提出了峰值电流-峰值电压(peak-current and peak-voltage,PCPV)控制方法.分析了PCPV控制...

Peak-Current and Peak-Voltage Control Scheme for Single-Inductor Dual-Output Buck Converter

In order to reduce the output cross regulation of single-inductor dual-output (SIDO) buck converter in continuous conduction mode (CCM), a peak-current and peak-voltage (PCPV) control method is proposed. The circuit structure and operating principle of the PCPV-controlled SIDO buck converter are analyzed. The gain expressions of input voltage and output voltage are deduced according to the principle of inductor volt-second balance and capacitor ampere-second balance. The state space average model of PCPV-controlled SIDO buck converter is established by using the state space average method. On this basis, the small signal model of PCPV-controlled SIDO buck converter is established, which is compared with traditional peak-current-mode (PCM) controlled SIDO Buck converter in the cross regulation. The research results show that the cross regulation from the higher voltage output branch to lower voltage output branch of PCM controlled SIDO Buck converter is 300 mV, and its transient regulation time of load variation is 12.5 ms. However, the proposed converter can reduce the cross regulation to almost zero and reduce the transient regulation time to 10 ms. Compared to the PCM controlled SIDO buck converter, the proposed PCPV-controlled SIDO Buck converter can effectively reduce the cross regulation and improve the transient performance. Finally, the theoretical analysis of the proposed method is verified by experimental results.