The limitation of theDC protection device confines the development of MV/LVDC grids. This paper presents a DC dynamic voltage restorer to exploit DC custom power devices for DC distribution networks in principle. It is based on an improved AC/DC dual active bridge and battery energy storage to maintain the voltage profile of sensitive loads in DC networks. The principle of the improved DC-DVR has been analyzed from the perspectives of the range of compensated voltage, current characteristics, and control strategy. Compared with other existing methods, the proposed DC-DVR features a simple structure, an easy control strategy, and the ability to mitigate both voltage sag and swell by injecting forward or reverse voltage. Experiment results demonstrate the correctness of the theoretical analysis and the feasibility of the proposed structure. A case study of DC doubly-fed induction generator (DFIG) interfaced with power grid is carried out, integrated with the proposed DC-DVR to verify the operation principle of the proposed scheme.

中文翻译：

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一种用于直流可再生电源保护的基于电池储能的直流动态电压恢复器

直流保护装置的局限性限制了MV/LVDC电网的发展。本文提出了一种直流动态电压恢复器，原则上利用直流配电网络的直流定制功率设备。它基于改进的 AC/DC 双有源桥和电池储能，以维持 DC 网络中敏感负载的电压分布。从补偿电压范围、电流特性、控制策略等方面分析了改进型DC-DVR的原理。与其他现有方法相比，所提出的 DC-DVR 结构简单，控制策略简单，并且能够通过注入正向或反向电压来缓解电压骤降和骤升。实验结果证明了理论分析的正确性和所提结构的可行性。