跨电压等级同杆四回线接地距离保护的研究  

Ground distance protection for four joint transmission lines with different voltage grades on the same tower

作　　者：马晓明[1] 范春菊[1] 刘玲[2] 

机构地区：[1]上海交通大学电气工程系,上海200240 [2]江西省电力设计院,江西南昌330006

出　　处：《电力系统保护与控制》2011年第24期28-34,共7页Power System Protection and Control

基　　金：国家自然科学基金项目(50807037)~~

摘　　要：详细分析了零序互感对接地距离保护的整定计算以及保护的动作特性的影响,推导了在不同运行条件下同杆四回线的零序补偿系数的计算公式,并且对各种情况下的零序补偿系数进行比较以确定在整定计算中采用的算法从而保证接地距离保护的正确动作。在此基础上,给出了不同电压等级同杆四回线零序补偿系数的计算方法以及补偿电压的计算方法,且对于带补偿系数的接地距离保护进行了仿真研究,仿真结果表明,该接地距离保护的抗过渡电阻能力比较差。为了提高接地距离保护的抗过渡电阻能力,研究了接地多相补偿距离继电器在不同电压等级的同杆四回线的接地保护中的应用,详细分析了过渡电阻对零序电抗继电器的影响。该零序电抗继电器具有较强的抗过渡电阻的能力,对于不同电压等级的同杆四回线路,不失为一种有效的接地保护方式。The impact of mutual inductor on setting computation and operation characteristic of ground distance protection are analyzed in detail. A zero-sequence current compensation coefficient of ground-fault distance protection for four-parallel line on the same tower is discussed especially and algorithm of relay settings is presented for correct operation of ground distance protection. Algorithm of zero-sequence current compensation coefficient and compensate voltage for four-parallel line of different voltage grades is proposed. And simulation research is done for ground distance protection with compensation coefficient. Research shows that this protection scheme almost cannot reflect transition resistance. In order to increase the ability of anti-transition resistance, the multiphase-compensated ground distance protection is proposed to be used in four transmission lines. The zero sequence reactance relay and its ability of anti-transition resistance are analyzed in detail. Analysis shows that transition resistance has little effect on zero sequence reactance relay. The multiphase-compensated ground distance protection can be used in the ground protection of four-parallel line of different voltage grades.

关 键 词：四回线 零序补偿系数 接地距离保护 过渡电阻 零序电抗继电器 

分 类 号：TM773[电气工程—电力系统及自动化]