A Neutral Point Potential Balancing Strategy for Three-Level T-Type Inverter Based on Deadbeat Control
Feng Teng1,2, Kang Longyun1,2, Hu Bihua1,2, Feng Yuanbin1,2
1. School of Electric Power South China University of Technology Guangzhou 510640 China; 2. Guangdong Key Laboratory of Clean Energy Technology South China University of Technology Guangzhou 510640 China
Abstract:To solve the problem of neutral point (NP) potential unbalancing of three-level T-type inverter, this paper puts forward a NP potential balancing strategy based on deadbeat control algorithm. Firstly, a mathematical relationship among NP potential variation, phase current and duty cycle of switch vectors was built. Then, an evaluation index describing the ability of regulating NP potential of short vector was introduced, i.e. when two short vectors existed simultaneously, different switching modulation methods were chosen through comparing their regulation capabilities. Thereby, a NP potential balancing method based on a deadbeat control algorithm was established. The duty cycle of the short vector, whose regulation ability was stronger, was adjusted to fast realize the NP potential balancing. The simulation and experimental results show that the proposed method has a good performance on NP potential balancing. It can suppress the NP potential fluctuation while reducing the harmonics of output voltage and current.
冯腾, 康龙云, 胡毕华, 冯元彬. 基于无差拍控制的T型三电平逆变器中点电位平衡策略[J]. 电工技术学报, 2018, 33(8): 1827-1834.
Feng Teng, Kang Longyun, Hu Bihua, Feng Yuanbin. A Neutral Point Potential Balancing Strategy for Three-Level T-Type Inverter Based on Deadbeat Control. Transactions of China Electrotechnical Society, 2018, 33(8): 1827-1834.
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