The Research on the Control Strategy of PET under unbalanced Load
Zhou Ke1, Ge Qin2, Ge Pingjuan2, Li Yuantao2, Wang Bin3
1. Electric Power Research Institute of Guangxi Power Grid Nanning 530023 China; 2. National Electric Power Conversion Control Engineering Technology Research Center Hunan University Changsha 410082 China; 3. Beihai Power Supply Bureau of Guangxi Power Grid Beihai 536000 China
Abstract:The symmetry of the output voltage is an important indicator for evaluating the performance of a power electronic transformer (PET). The main cause of the asymmetry of the PET output voltage is the presence of unbalanced loads. This paper proposes an unbalanced operation optimization strategy based on its topological characteristics for modular output parallel power electronic transformers. First, this paper briefly analyzes the modular parallel operation strategy of PET output stage and establishes the output stage control model. Then, the adverse effects of unbalanced load on the output voltage of the power electronic transformer are analyzed, and then the classic master-slave control strategy of the output stage is improved. Based on the operation of the master power module, power follow control is performed through the slave power. Finally, the effectiveness and feasibility of the proposed topology and control strategy are verified by simulation and experiments.
周柯, 葛钦, 葛平娟, 李元涛, 王斌. 不平衡负荷下输出并联型电力电子变压器的优化控制策略[J]. 电工技术学报, 2018, 33(zk1): 149-156.
Zhou Ke, Ge Qin, Ge Pingjuan, Li Yuantao, Wang Bin. The Research on the Control Strategy of PET under unbalanced Load. Transactions of China Electrotechnical Society, 2018, 33(zk1): 149-156.
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