基于调制波重构的级联H桥型变流器直流电压均衡控制原理分析

摘要

为了抑制级联H桥型变流器直流电压的不均衡,分析变流器交流侧和直流侧的功率传输,然后以调制波重构的思想详细分析直流电压均衡控制的原理.提出基于单位化的变流器输出电流构造调制波微调量的改进直流电压均衡方法.根据分析结果,给出在整流、无功补偿、谐波补偿等应用场合直流电压均衡控制策略的构成方法及建议.仿真和实验结果表明直流电压均衡控制策略的有效性.%For imbalance suppression of the cascaded H-bridge DC voltages, the power flow in the AC and DC sides is analyzed. The principle of DC voltage balance control strategy is then illustrated in detail in the view of modulation signal reconstruction. Based on the modulation wave adjustment made up by the normalized converter current, an improved DC voltage balance control strategy is proposed. According to the analytical results, the methods and suggestions of the DC voltage balance control strategy are proposed in rectifier, reactive power compensation and harmonics compensation applications. Simulation and experimental results show the effectiveness of the DC voltage balance control strategy.