Abstract:The virtual synchronous machine technology can make power electronic converters exhibit damping and inertia characteristics similar to conventional synchronous machines, which is beneficial to the friendly interaction of power sources or loads with the grid. However, due to the complicated conditions of the actual grid, the distortion of grid voltage always leads to serious grid-connected current distortion of virtual synchronous converters. Thus, this paper proposes a harmonic-current suppression method for the virtual synchronous rectifier to solve this problem. Firstly, the influence mechanism of grid harmonic voltage on grid-connected current of virtual synchronous rectifier was investigated through impedance analysis. Secondly, a feedforward method of grid harmonic voltage was proposed accordingly. By increasing the grid-side impedance at the harmonic frequency, the influence of grid harmonic voltage on grid-connected current was weakened, then the current harmonics were suppressed accordingly. Finally, the selection method of feedforward factor was developed by small signal analysis, and the system steady-state and dynamic performance was evaluated. Simulation and experimental results verified the proposed method.
徐健, 曹鑫, 郝振洋, 杨奇. 基于电网谐波电压前馈的虚拟同步整流器电流谐波抑制方法[J]. 电工技术学报, 2022, 37(8): 2018-2029.
Xu Jian, Cao Xin, Hao Zhenyang, Yang Qi. A Harmonic-Current Suppression Method for Virtual Synchronous Rectifier Based on Feedforward of Grid Harmonic Voltage. Transactions of China Electrotechnical Society, 2022, 37(8): 2018-2029.
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