Abstract:During the grid synchronization of the distributed generation units, phase-locked loop(PLL) is well accepted as an efficient approach to detect grid phase angle. For the conventional PLL scheme, there’s a compromise between tracking accuracy and dynamic performance if the grid voltage is distorted. However, the delayed signal cancellation(DSC) operators can eliminate unbalance component and low order harmonics effectively, and thus the bandwidth of the system can be improved. Based on the DSC operators, this paper proposes a two-type three-order controller which can significantly improve the ability of the PLL to reject high order harmonics, and also proposed a method which can directly calculate the control parameters based on phase margin and harmonic rejection requirements without the try and error procedure. A phase-locked loop system prototype is built and tested in the lab. The experimental results are given to verify the validity of theoretical analysis presented above.
吴恒, 杨东升, 阮新波. 基于串联信号延迟对消法的三相非理想电网锁相控制策略[J]. 电工技术学报, 2014, 29(8): 255-264.
Wu Heng, Yang Dongsheng, Ruan Xinbo. Phase-Locked Loop Based on Cascaded Delayed Signal Cancellation for Distorted Grid. Transactions of China Electrotechnical Society, 2014, 29(8): 255-264.
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