Active Damping Method Based on State-Feedback for Grid-Connected Inverter with LCL Filter
Zhang Qi1,2, Li Rui1, Zhang Yongping1, Ren Biying1, Sun Xiangdong1,2
1. Department of Electric Engineering Xi’an University of Technology Xi’an 710048 China;; 2. Shaanxi Key Laboratory of Complex System Control and Intelligent Information Processing Xi’an University of Technology Xi’an 710048 China;
Abstract：Based on discrete state space model analysis for LCL grid-connected inverter, an active damping method is proposed to settle down the stability problems caused by the grid impedance variation and the digital time delay. The common coupling point voltage vpcc is used as a system state, and its feedback characteristics is studied to reveal its damping effect. In addition, the states feedback characteristics of inverter current ii and grid current ig are evaluated respectively. Consequently, a state reconstruction method is provided, which relies on the sampling values of vpcc and ig. Meanwhile, the order of the space model is virtually enlarged to improve the system stability. The feasibility and effectiveness of the proposed control method are verified by Matlab/Simulink simulations and experiments.
张琦, 李锐, 张永平, 任碧莹, 孙向东. 具有主动阻尼特征的LCL并网逆变器状态反馈控制方法[J]. 电工技术学报, 2019, 34(8): 1698-1707.
Zhang Qi, Li Rui, Zhang Yongping, Ren Biying, Sun Xiangdong. Active Damping Method Based on State-Feedback for Grid-Connected Inverter with LCL Filter. Transactions of China Electrotechnical Society, 2019, 34(8): 1698-1707.
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2019, Vol. 34 
