输电线路纵差保护动作的影响因素及补救措施

Influence Factors and Remedial Measures of Transmission Line Differential Protection Action

针对输电线路不平衡电流、分布电容电流以及负荷电流对差动保护的影响,通过对差动保护原理的分析和线路中的电流计算.结果表明,采用同型号的电流互感器、对分布电容电流进行补偿、把电流的故障分量作为纵差保护的判据等措施,可以明显提高纵差动保护的灵敏度和可靠性.

The unbalance current on transmission line,the distributed capacitance current and the load current have an influence on the differential protection. Through the analysis of the differential protection principle and the calculation of current in a circuit,the results show that it can significantly improve the sensitivity and reliability of differential protection that applying the same model of current transformer to compensate the distributed capacitance current and taking the current fault component as differential protection criterion.