用于直流微电网线路的新型不平衡保护研究

Research on Novel Imbalance Protection for DC Microgrid Lines

直流微电网中所配置的线路保护需要兼顾速动性与选择性,为解决这一难题,提出了一种基于双回供电线路的直流微电网线路保护方案。通过分析直流微电网双回路供电下的线路故障特征,发现双回路的供电形式能提供故障状态下的不平衡信息,使得保护装置通过基于单端测量获取的电流信号量实现故障检测,同时双回路的供电方式采用本方案能清除线路的故障部分而不会影响供电。针对典型的极地故障,通过仿真的形式验证了所提保护方案的可行性。

The line protection in DC microgrid needs to be both quick and selective.To solve this problem,a line protection scheme of DC microgrid based on double-circuit power supply line is proposed.In this paper,by analyzing the fault characteristics of the line under the double-circuit power supply of the DC microgrid,it is found that the power supply form of the double-circuit can provide imbalanced information under the fault state,so that the protection device can realize fault detection through the semaphore of current obtained based on the single-end measurement.Meanwhile,the power supply mode of the double-circuit can clear the fault part of the line without affecting the power supply.For typical polar faults,this paper verifies the feasibility of the proposed protection scheme through simulation.