基于工频变化量的序分量距离保护

摘要

In order to adapt to the low current fault characteristic of island operation, the protection of the distributed power island operation is different from the protection of the parallel operation. But as the increase of the frequency of input and resection of the distributed power, the set values of the protection must also frequently convert between different protection methods. So sequence components distance protection based on power frequency variation is put forward. Taking the short circuit fault of negative sequence voltage as an example, this paper analyzes the distribution of voltage, obtains the operating criterion of negative sequence and zero sequence relay, and builds the simulation module of negative sequence and zero sequence relay in the MATLAB. In the environment of grid-connected and islanding operation respectively, the simulation analysis of the action of the proposed method in the situation of different fault distance and transition resistance is conducted, which verifies its reliability.%　　为了适应孤岛运行低电流值的故障特性，一般分布式电源孤岛运行时的保护方法与并网运行时的不同。但是随着分布式电源投入和切除配电网频率的增加，保护的整定值也必须频繁地在不同保护方法之间转换。所以提出了基于工频变化量的序分量距离保护，以短路故障时负序电压为例，对其电压分布进行分析，得出了负序和零序继电器的动作判据，并在Matlab中搭建负序和零序继电器的仿真模块。通过仿真分析了在并网和孤岛两种情况下，该保护方法在不同故障距离和过渡电阻情况下的动作情况，从而验证了该保护方法在并网和孤岛两种方式下均能够可靠动作。