换相失败对距离保护的影响分析及防范措施的研究  

Effect of commutation failure on distance protection and the countermeasures

作　　者：黄少锋[1] 费彬[1] 申洪明[1] 赵远[1] 

机构地区：[1]华北电力大学新能源电力系统国家重点实验室,北京102206

出　　处：《电力系统保护与控制》2014年第20期123-128,共6页Power System Protection and Control

基　　金：国家重点基础研究发展计划(2012CB215206)~~

摘　　要：交直流互联系统换相失败时引起的电磁暂态过程与纯交流环境时不同,因而会对距离保护的动作性能产生影响。以交流系统单相接地故障引发换相失败为例,将换相失败等效为双故障源模型,详细分析了换相失败对接地距离继电器的影响。分析结果表明传统的傅氏算法在换相失败时不能很好地准确测量短路电抗值。然后定义了混联系统中交流保护风险因子的概念及其表达式,并进一步地从风险因子和算法两方面提出了相应的解决措施。最后通过PSCAD/EMTDC仿真验证了结论的准确性,并对几种可能的解决措施进行了比较,比较结果表明解微分方程算法在换相失败时性能更好。The transient process caused by commutation failure in AC-DC interconnected system is not the same as that in pure AC system, which has effect on the performance of distance protection. This paper takes single-phase earth fault as an example to analyze the effect of commutation failure on ground distance relay based on double fault sources model. Analysis results show that the calculated short circuit reactance is not accurate by using Fourier algorithm during commutation failure. Then, AC risk factor is defined and its expression is also provided. Then, the countermeasures are put forward based on AC risk factor and protection algorithm. At last, a large amount of simulation results using PSCAD/EMTDC prove the conclusion to be reasonable and the countermeasures are compared. The comparison results show that differential equation algorithm has better performance in commutation failure environment.

关 键 词：换相失败 距离保护 非周期分量 风险因子 微分方程算法 

分 类 号：TM773[电气工程—电力系统及自动化]