Abstract:The rapid and reliable identification and accurate isolation of fault elements in DC distribution network is one of the technical difficulties restricting its development. Aiming at the DC distribution mode of fault self-cleaning converter combined with quick disconnecting switch, this paper presents a method of identifying fault elements without detecting the electrical quantity at both ends of the line. Firstly, the calculation method of bus virtual voltage based on network structure and bus electrical quantity is studied. Based on the difference of virtual voltage of bus at different fault positions, a fast identification and location method of DC line faults is studied, and an auxiliary identification method for bus faults and line end faults is proposed by using the switching selection of submodules in the converter. The fault element identification method only uses the outlet current of the converter and the bus voltage to realize the rapid identification of the fault element of the full distribution network, without measuring the electrical quantity at both ends of the line, and is not limited by the distribution network structure, taking into account the economy and reliability.
李博通, 刘涛, 杨昕陆, 温伟杰, 李斌. 故障自清除型直流配电网新型双极短路故障元件识别方法[J]. 电工技术学报, 2022, 37(17): 4423-4434.
Li Botong, Liu Tao, Yang Xinlu, Wen Weijie, Li Bin. New Fault Element Identification Method of Bipolar Short-Circuit Fault in DC Distribution Network with Fault Self-Clearing. Transactions of China Electrotechnical Society, 2022, 37(17): 4423-4434.
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