Abstract When a fault occurs at a grid-connected photovoltaic (PV) system, the grid voltage drops significantly, and this causes a spike in the DC link voltage. The high DC voltage, in turn, causes faults in the Power-Electronics inverters and choppers. In addition, PV plants form a significant portion of modern power systems and disconnecting them during faults (as conventional) is no longer an option. This work proposes the dynamic voltage restorer (DVR) to improve the fault ride-through (FRT) capability of PV systems under a three-phase-to-ground fault. In order to evaluate the effectiveness of the proposed DVR method, its performance is compared with that of the series dynamic braking resistor (SDBR). The comparison is made in terms of performance and control complexity. Simulation results show that the DVR can improve the FRT capability seamlessly. Also, despite its higher cost and controller complexity, the proposed DVR outperforms the SDBR in all aspects.

中文翻译：

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使用动态电压恢复器提高并网光伏系统的故障穿越能力

摘要 当并网光伏（PV）系统发生故障时，电网电压会显着下降，从而导致直流母线电压出现尖峰。反过来，高直流电压会导致 Power-Electronics 逆变器和斩波器出现故障。此外，光伏电站是现代电力系统的重要组成部分，在出现故障时将其断开（如常规）不再是一种选择。这项工作提出了动态电压恢复器 (DVR)，以提高光伏系统在三相接地故障下的故障穿越 (FRT) 能力。为了评估所提出的 DVR 方法的有效性，将其性能与串联动态制动电阻器 (SDBR) 的性能进行比较。比较是在性能和​​控制复杂度方面进行的。仿真结果表明，DVR 可​​以无缝地提高 FRT 能力。此外，尽管其成本和控制器复杂性更高，但所提出的 DVR 在所有方面都优于 SDBR。