Abstract：In a microgrid, the point of common coupling (PCC) voltage is easily featured by distortion, imbalance, frequency offset and phase mutation due to high renewable energy penetration, large line impedance and random variation of the generators’ output power and loads. This will cause the voltage and current detection errors of grid-connected inverters and thus lead to unexpected operation of the inverters if a traditional detection algorithm is employed. In this paper, the voltage phase and current are detected based on a virtual synchronization frame (VSF) given rotation speed and direction. This VSF-based detection algorithm is suitable for the grid condition of voltage distortion, imbalance and frequency offset, can detect any specified voltage phase and current components in parallel, doesn’t need to set PI parameters, has better dynamic performance than the detection algorithm using improved phased-locked loop (PLL) when voltage phase mutation occurs. In simulations and experiments, the detection algorithm, applied to the active power filter (APF), not only can accurately detect the voltage phase and current under non-ideal voltage condition mentioned above, but also the dynamic delay is less than one cycle.
张晓滨, 黄佳敏, 伍文俊, 苏战停. 基于虚拟同步坐标变换的交流微电网并网逆变器电压相位和电流检测算法[J]. 电工技术学报, 2018, 33(13): 3119-3129.
Zhang Xiaobin, Huang Jiamin, Wu Wenjun, Su Zhanting. A Voltage Phase and Current Detection Algorithm Based on Virtual Synchronization Frame for AC Microgrid Grid-Connected Inverters. Transactions of China Electrotechnical Society, 2018, 33(13): 3119-3129.
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