基于新型励磁电流偏差计算的发电机转子绕组匝间短路检测  

Inter-turn Short Circuit Detection of Rotor Winding in Turbine Generators based on the New Excitation Current Deviation Calculation

作　　者：白雨卉 武玉才[1] BAI Yuhui;WU Yucai(Department of Electric Power Engineering,North China Electric Power University,Baoding 071003,China)

机构地区：[1]华北电力大学电力工程系,河北保定071003

出　　处：《大电机技术》2024年第6期1-7,44,共8页Large Electric Machine and Hydraulic Turbine

基　　金：国家自然科学基金资助项目(52277048)。

摘　　要：为对汽轮发电机的转子故障做出精准识别,本文基于转子磁极线圈匝间短路造成的发电机磁场损失,推导得出电磁转矩的实际值小于期望值这一特点,从而提出一种在线检测转子磁极线圈不稳定匝间短路的新型方法。该方法首先通过发电机的二维静态电磁有限元仿真获取机组运行的励磁电流理论值;然后进行多工况下的仿真计算,生成励磁电流关于有功和无功的三维曲面,利用二元插值法实现任意工况的发电机励磁电流理论值的快速求解;最后通过理论值与实际值偏差判断转子磁极线圈是否存在匝间短路。故障实例表明,该诊断方法可在保证计算速度及精度的前提下,实现对转子磁极线圈匝间短路的有效监测。In order to accurately identify the rotor fault of the turbine generator,based on the magnetic field loss of the generator caused by inter-turn short circuit of the rotor pole coil,this paper deduces that the actual value of the electromagnetic torque is less than the expected value.Therefore,a new method for detecting unstable inter-turn short circuit of rotor magnetic pole coil is proposed.Firstly,obtain the theoretical value of the excitation current of the unit through 2-D static electromagnetic finite element simulation.Further,through the simulation calculation of multiple working conditions,the 3-D surface of excitation current about active and reactive power is generated.The binary interpolation method is used to quickly calculate the theoretical value of excitation current under any working condition of the generator.Finally,the rotor magnetic pole coil inter-turn short circuit fault is judged by the deviation between the theoretical and actual values.The fault case proves this method can effectively monitor the rotor magnetic pole coil inter-turn short circuit fault.

关 键 词：汽轮发电机 磁极线圈 匝间短路 电磁转矩 励磁电流 故障诊断 

分 类 号：TM311[电气工程—电机]