峰值电流模式的移相半桥三电平DC/DC变换器闭环系统建模研究

半桥三电平变换器拓扑解决了PFC技术带来的功率管应力过高问题,非常适合于大功率高压输出场合,峰值电流模式采用电压外环,电流内环的双环控制,是开关电源闭环系统最实用的控制模式.对移相半桥三电平DC/DC变换器进行了小信号建模分析;建立了峰值电流内环和电压外环的小信号传递函数,在此基础上给出了峰值电流模式的移相半桥三电平变换器闭环系统结构图,推导出相关闭环传递函数;给出了补偿网络参数设计步骤;对建立的双闭环系统模型进行了MATLAB仿真,结果表明经过补偿后的闭环系统具有满意的性能指标.

Modeling Study on Closed-Loop System of Phase-Shifted Half-Bridge Three-Level DC/DC Convertor Based on Peak Current Mode

The technology of PFC is originated from clearance-up of power line harmonic wave,but it has brought forth the problem of high stress of power transistors.The topology of half-bridge Three-Level convertor has solved the problem and suit the application of high voltage and large power output.As most practical control mode in switch power supply systems,Peak-current control mode is composed of peak current inner loop and voltage outer loop.The paper analyzes the small-signal model for phase-shifted half-bridg...