一种双向隔离DC-DC变换器二次纹波电压抑制方法

摘要

针对双向隔离 DC-DC 变换器二次纹波电压抑制问题,提出一种基于该变换器大信号数学模型的反馈线性化二次纹波扰动前馈的移相控制方法.该方法以双向隔离 DC-DC 变换器大信号状态空间平均方程数学模型为基础,采用反馈线性化方法结合输出扰动量前馈移相控制,将非线性控制转换为线性控制,实现耦合控制变量的解耦,并推导出该方法下的控制规则.对控制规则进行详细推导,并根据控制规则设计基于可编程逻辑器件的控制核心.最后,通过小功率单相三电平二极管钳位 AC-DC-DC 变换器实验系统,验证了所提控制方法比传统 PI 控制和电压前馈控制具有更好的二次纹波电压抑制能力.%In order to suppress the second-order ripple voltage of bidirectional isolation DC-DC converter, a second order ripple feedforward phase-shift control with feedback linearization is proposed. Based on the large signal state-space-averaged modeling, this control includes a phase-shift algorithm of feedback linearization and an output disturbance feedforward algorithm. By converting the nonlinear to linear model, the coupling control variable is decoupled. Then the control rules according to this method is derived and designed on programmable logic device. Finally, a small scale single-phase three-level diode-clamped bidirectional isolation AC-DC-DC converter is tested. The experimental results verifies that the proposed control method has better suppression ability of the second-order ripple voltage suppression than conventional PI control and input voltage feedforward control.