双级式储能变流器波形控制策略研究

Research of waveform control strategy for dual-stage power conversion system

针对储能变流器双向能量控制的电流谐波问题,提出了一种基于双级式主电路拓扑的电流波形综合控制策略。在直流侧为减小滤波电感体积,采用双重化电路和载波移相控制方法有效抑制输出电流纹波,降低开关损耗;在交流侧为提高系统并网电能质量,采用PI控制和重复控制并联的复合控制方法有效抑制了并网电流的谐波含量,提高了系统的动态响应速度。实验结果验证了该控制策略的有效性和可行性。

In view of problem of harmonic current existed in power conversion system with bi- directional energy control, an integrated current waveform control strategy based on dual-stage main circuit topology was proposed. Double circuit and carrier phase-shifting control method are used in DC side in order to reduce volume of filter inductor, which effectively decreases output current ripple and switching losses. A hybrid control method based on PI control and repetitive control is applied in AC side in order to improve grid-connected power quality, which effectively suppresses harmonic content of grid-connected current, and improves dynamic response speed. The experimental results verify effectiveness and feasibility of the control strategy.