串联补偿线路电流反向对差动保护的影响及对策
Influence and Countermeasures for Current Reversal on Differential Protection of Series Compensated Lines
-
摘要: 随着电力系统的发展,串联补偿线路上原来并不存在的电流反向问题逐步显现。文中详细分析了串联补偿线路发生电流反向的机理,针对应用最广泛的电流差动保护分析电流反向对其的影响。分析结果表明,作为保护高阻接地的零序差动保护在电流反向时可能发生灵敏度降低甚至拒动的情况。提出了一种新的零序差动保护改进算法,不仅可以有效解决灵敏度降低的问题,同时具有普适性,可用于各种类型串联补偿线路。仿真实验和实际工程应用验证了该方法的有效性和可靠性。Abstract: With the development of power systems,the originally nonexistent problem of current reversal on series compensated transmission lines due to overcompensation is getting more and more apparent.An in-depth analysis is made on the factors related to current reversal,and the influence of current reversal on current differential protection.The results show that current reversal may cause reduced sensitivity of zero sequence differential protection for high resistance earth fault,and even rejection of operation for internal fault.A novel algorithm for zero sequence current differential protection is proposed,which is capable of not only solving the problem of sensitivity reduction,but also universal application to various types of series compensated lines.Simulation test and actual application have proved the effectiveness and reliability of the method proposed.
下载:
