Abstract：The grid-connected inverter which employs phase lock loop (PLL) with drooped characteristic can obtain unity power factor. However, the islanding can’t be detected when the resonant frequency of parallel RLC load is in the range of normal power grid frequency. Compared to other islanding detecting method, this zone is relatively larger. In order to decrease the NDZ, an improved PLL is proposed, which introduces a phase difference disturbance to the drooped PLL. The principle of parameters selecting is given and the NDZ of the improved PLL strategy is significant decreased. The simulation and experimental results verify that the proposed method is effective for islanding detection without affecting the quality of grid current.
阚加荣, 罗运虎, 谢少军, 顾春雷, 吴云亚, 姚志垒. 基于下垂特性锁相环的反孤岛性能分析[J]. 电工技术学报, 2013, 28(4): 165-170.
Kan Jiarong, Luo Yunhu, Xie Shaojun, Gu Chunlei, Wu Yunya, Yao Zhilei. Analysis with Anti-Islanding Performance of Grid-Connected Inverters Based on Drooped PLL. Transactions of China Electrotechnical Society, 2013, 28(4): 165-170.
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