电力系统保护与控制2011，Vol.39Issue(18)：72-79,8.
不同电压等级的四回线的纵联差动保护方案
New longitudinal differential protection scheme for four-circuit transmission line with different voltage grades
摘要
Abstract
To solve the problem that the traditional longitudinal differential protection used in four-circuit transmission line on the same pole with different levels will be seriously affected by coupling inductance, a new longitudinal differential protection scheme based on inverse-sequence negative sequence difference current is proposed. Four-circuit transmission lines with different voltage grades generally consist of two double circuit transmission lines at the same tower. However, when line parameters are symmetry, the inverted sequence current is zero when the system operates normally or external faults occur. Once internal faults occur, there is inverted current in the transmission line, and the sum of inverted current at both sides is large, so the differential protection based on inverted current can operate correctly. For this method, the reliability and sensitivity under big fault resistance can be kept. And it will not be affected by capacitive current when it is applied to the main protection of four-circuit transmission line with different voltage grades. The theoretical analysis and EMTP simulation results show that the proposed principle is correct and reliable.关键词
同杆四回线/反序环流量/分相电流差动保护/不同电压等级/EMTP仿真Key words
four-circuit transmission lines at the same tower/ inverted current/ single-phased current differential protection/ different voltage grades/ EMTP simulation分类
信息技术与安全科学引用本文复制引用
陈金熠,范春菊,刘玲..不同电压等级的四回线的纵联差动保护方案[J].电力系统保护与控制,2011,39(18):72-79,8.基金项目
国家自然科学基金项目(50807037) （50807037）
