一种电力电子变压器的控制策略研究

Control strategy research for power electronic transformer

对一种基于双向DC-DC变换器的电力电子变压器进行了深入分析,针对现有电力电子变压器整流侧所采用基于D-Q变换均压控制算法复杂的问题,提出一种基于电压排序的直流电容电压平衡控制算法,无需单相D-Q变换,简化了控制结构,提高了均压控制效果。针对现有电力电子变压器多DC-DC单元并联的功率均衡控制所需要信号采样多的问题,提出一种不需要电流采样DC-DC单元并联均功率控制策略,减小了采集信号数量。仿真和实验结果验证了文中所提出控制策略有效性。

Based on the in-depth analysis of PET with bi-directional DC-DC converter,a voltage balance control strategy based on voltage sorting is proposed to take the place of the existing excessive controller and complex control method of D-Q conversion based voltage control strategy.The proposed strategy,which needs fewer controllers,simplified the system control and made the voltage balance control effect better.The existing power balance control strategy needs increasing sampled current signals as the number of the series cascaded units rises,and a new power balance control method which does not need current sampling,is proposed in this paper.The validity of proposed control strategies is verified through simulation and experiment results.