工频变化量距测试及应用

对工频变化量距离保护的校验方法进行了研究,《电力系统继电保护规定汇编》中的校验方法将工频变化量距离元件视为一个过电压继电器,而《电力系统继电保护实用技术问答》中的计算公式则是基于传统距离继电器的概念,比较了2种方法的优点及不足。国产继电保护试验仪一般都有针对工频变化量的专用测试菜单,而进口仪器则需预先计算和设置。结合上海电网具有短路容量大、电气距离短的特点,提出了使用进口仪器测试工频变化量距离保护的具体方法。最后,对工频变化量距离保护的开放条件的必要性作了分析。

Test and application of power frequency variation distance protection

Test methods of power frequency variation distance protection are researched.The method in" The rules of power system protection" takes power frequency variation distance element as an over-voltage relay while the computing formula of the method in "The technical questions and answers of power system protection" is based on the traditional distance relay,these two methods are compared.The appropriative test menu for"power frequency variation" is normally built in domestic relay protection test instruments,but it should be calculated and set beforehand for imported instruments.For Shanghai power grid,which has large short circuit capacity and short electrical distance,a method using imported instrument to test power frequency variation distance protection is presented.The necessity of the open condition for power frequency variation protection is analyzed.This project is supported by the Shanghai Key Project of Science and Technology(041612012)and the Shanghai Leading Academic Discipline Project(P1301).