电容箝位五电平H桥变换器拓扑及调制策略

Topology and Modulation Strategy of Capacitor-clamped Five-level H-bridge Converter

在电容箝位三电平电路基础上,借鉴常规H桥级联电路结构,构建了电容箝位五电平H桥变换器,对该变换器拓扑结构采用梯形波脉冲宽度调制策略,即将单个三角载波信号与多个梯形波调制信号进行规则对称采样的方法进行控制。与其他常用脉冲宽度调制方法相比,该调制方法下的输出基波电压幅值更高。仿真结果表明,该拓扑结构和控制策略是可行的。

Capacitor-clamped five-level H-bridge converter was researched based on capacitor-clamped three-level circuit and structure of general cascaded multilevel H-bridge.The modulation strategy of trapezoidal PWM was adopted.The single triangle carrier signal and multi trapezoidal modulation signals were symmetrically sampled by rule.The amplitude of output fundamental component by the proposed scheme was higher than that by other common used PWM methods.Finally,detailed simulation results verified the proposed topology and control method.