一种适用于Y/△接线变压器的励磁电感计算方法  

An Algorithm to Calculate the Excitation Inductance of Power Transformer with Y-Delta Connection

作　　者：索南加乐[1] 焦在滨[1] 宋国兵[1] 张怿宁[1] 康小宁[1] 

机构地区：[1]西安交通大学电气工程学院,陕西省西安市710049

出　　处：《电力系统自动化》2007年第9期32-36,67,共6页Automation of Electric Power Systems

基　　金：国家自然科学基金资助项目(50677051)~~

摘　　要：现有的励磁电感计算方法需要使用变压器各侧绕组电流,按照典型的电流互感器配置方案,Y/△接线方式变压器△侧绕组电流未知,故不能直接利用现有方法求得励磁电感。提出了一种适用于Y/△接线变压器的励磁电感计算方法,不需要测量绕组电流,直接利用△侧线电流,在分相列写回路方程的基础上,消去绕组环流的影响,计算各相的励磁电感。EMTP仿真验证了该算法的正确性。结果表明,基于该算法得到的励磁电感能准确、有效、灵敏地识别励磁涌流和内部故障状态,在超高压大容量变压器及220kV以下电力变压器的保护方面具有较好的工程应用前景。A computational method of excitation inductance of power transformer needs current of all windings. However the excitation inductance of power transformer with Y-Delta connection cannot be calculated directly using any existed method because the winding currents on the Delta side cannot be measured based on existed TA. An algorithm to calculate the excitation inductance of power transformer with Y-Delta connection is proposed in the paper. Based on the equivalent circuit equation, the excitation inductance of power transformer with Y-Delta connection is calculated by using the line currents on the Delta side directly and by eliminating the internal currents of windings on the Delta side. The algorithm accuracy is verified by EMTP simulation. The result shows that the excitation inductance calculated using the algorithm proposed can reflect the transformer and its iron core status accurately, effectively and sensitively. It can be used as the criterion of transformer protection and has good project application prospect in the field of the transformer protection.

关 键 词：差动保护 励磁涌流 励磁电感 环流 Y/△接线变压器 

分 类 号：TM41[电气工程—电器]