变压器励磁涌流的自适应二次谐波分相制动方案  

An Adaptive Secondary Harmonic Split-phase Restrained Scheme for Magnetizing Inrush Current in Transformers

作　　者：李贞 张明珠[2] 倪传坤 邹欣洁 

机构地区：[1]许继电气股份有限公司技术中心,河南省许昌市461000 [2]许昌学院数学与统计学院,河南省许昌市461000

出　　处：《电力系统自动化》2013年第6期121-124,共4页Automation of Electric Power Systems

基　　金：河南省教育厅科学技术研究重点资助项目(12A110022)

摘　　要：Yd接线方式的大型变压器由于无法测量三角形绕组环流而采用线电流差动保护,可能出现对称性涌流导致涌流制动判据失效。文中提出一种利用变压器两侧电流互感器测量线电流计算三角形绕组电流的方法,通过计算得到的三角形绕组电流实现相电流差动保护,基于该方法形成一种Yd接线方式的变压器励磁涌流的自适应二次谐波分相制动方案,既可以自适应调整二次谐波制动比,又保证了空合于故障时的差动保护的动作速度,大大提高了变压器差动保护的性能。MATLAB/Simulink仿真结果验证了所提出方案的正确性和有效性。Currents through delta windings of transformers connected in wye-delta mode cannot be measured directly therefore line differential current is used to realize differential protection.The symmetry inrush current resulted from line differential current may invalidate the restrained criterion for inrush current.A method for calculating the current through delta windings utilizing the measured current from current transformers is proposed.With this calculated current the phase differential current can be obtained.Based on the method an adaptive secondary harmonic split-phase restrained scheme for magnetizing inrush current for transformers connected in wye-delta mode is presented.The scheme can greatly improve the performance of transformer differential protection because it can adaptively adjust the secondary harmonic ratio of restrained current,and guarantee the fast action when transformers with internal faults are no-load energized.Simulation results in MATLAB/Simulink validate the proposed scheme.

关 键 词：差动保护 励磁涌流 二次谐波制动 分相制动 

分 类 号：TM407[电气工程—电器]