适用于含新能源交流电网继电保护整定计算的故障计算方法研究

Research on Fault Calculation Methods for Relay Protection Setting Calculation in AC Power Grids Containing New Energy Sources

基于阻抗矩阵的故障计算方法以其计算量小、适用于局部求解等特性,在交流电网继电保护整定计算中得到了广泛应用。新能源的大范围接入改变了整定计算中故障计算的局部性特征,增加了故障计算所需内存、降低了故障计算效率。针对这一问题,该文基于含新能源的故障计算公式,根据新能源对故障节点的影响因素,提出了适用于含新能源交流电网继电保护整定计算的故障计算方法。首先,从网络结构方面,筛选对故障电气量具有强影响的新能源,构建初始计算域;其次,从新能源输出方面对初始计算域进一步增补和修正;最后,经过逐层外扩,形成最终计算域。在保证工程所需计算精度的同时,降低了矩阵元素使用率,减少了故障计算的计算量,提高了计算效率。在IEEE39节点、IEEE118节点系统中验证了该方法的准确度和计算效率。

The impedance matrix-based fault calculation method has been widely used in measuring relay protection for AC networks due to its small calculation size and applicability to local solutions.The widespread access to new energy sources has changed the local character of fault calculation,increasing the memory required for fault calculation and reducing the efficiency of fault calculation.This paper proposes a fault calculation method based on the formula for new energy sources and the influence of new energy sources on the fault nodes.This applies to the fault calculation of relay protection in AC networks with new energy sources.Firstly,the initial calculation domain is constructed by screening the new energy sources with strong influence on the fault electrical quantities from the network structure;secondly,the initial calculation domain is further supplemented and modified from the new energy output;finally,the final calculation domain is formed by layer-by-layer expansion.While ensuring the calculation accuracy required by the project,the usage rate of matrix elements is reduced,the calculation volume of fault calculation is reduced,and the calculation efficiency is improved.The accuracy and computational efficiency of the method were verified in the IEEE39 node and IEEE118 node systems.