Research on the Impacts of Digital Control Delay on the Effectiveness of Current Loop Decoupling
Zhang Sen1, Zhao Jianfeng1, Liu Kangli1, Zhao Zhihong2, Li Baorun1
1. School of Electrical Engineering Southeast University Nanjing 210096 China; 2. School of Automation Nanjing University of Science and Technology Nanjing 210094 China
Abstract：This paper analyzes the effect of digital control delay on the effectiveness of current loop decoupling (feed-forward decoupling and complex vector PI decoupling) in the synchronous rotating frame, revealing the nature of the decoupling failure under the condition of low switching frequency or high control frequency. And the delay compensation method for suppressing the current loop coupling is proposed. The advantages and disadvantages of the two decoupling methods are then compared in term of the decoupling effectiveness and the dynamic response speed of the current loop. Compared to the feed-forward decoupling, the coupling between d axis and q axis of complex vector PI decoupling is reduced by 50%, and the dynamic response speed is about twice. Simulation and experimental results are carried out to verify the correctness of the theoretical analysis.
张森, 赵剑锋, 刘康礼, 赵志宏, 李保润. 数字控制延时对电流环解耦有效性的影响[J]. 电工技术学报, 2020, 35(zk2): 484-493.
Zhang Sen, Zhao Jianfeng, Liu Kangli, Zhao Zhihong, Li Baorun. Research on the Impacts of Digital Control Delay on the Effectiveness of Current Loop Decoupling. Transactions of China Electrotechnical Society, 2020, 35(zk2): 484-493.
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2020, Vol. 35 
