负序磁场中同步发电机转子绕组匝间短路故障恶化的分析  

Deterioration Analysis of Inter-Turn Short Circuit Fault in Synchronous Generator Rotor Windings Under Negative Sequence Magnetic Field

作　　者：武玉才[1] 马倩倩 王逸仙 蔡波冲 WU Yucai;MA Qianqian;WANG Yixian;CAI Bochong(School of Electrical and Electronic Engineering,North China Electric Power University, Baoding 071003,China;Xingtai Power Supply Branch of National Grid Hebei Power Co.,Ltd.,Xingtai 055450,China)

机构地区：[1]华北电力大学电气与电子工程学院,河北保定071003 [2]国网河北省电力有限公司邢台供电分公司,河北邢台055450

出　　处：《电机与控制应用》2018年第10期126-133,共8页Electric machines & control application

基　　金：河北省自然科学基金项目(E2016502031);中央高校基本科研业务费专项资金项目(2017MS106)

摘　　要：以1台300 MW同步发电机为例,考虑了阻尼系统,在不对称运行条件下,研究了励磁绕组匝间短路后发电机的相关故障特征量,包括励磁电流、励磁绕组的感应电动势、被短路的励磁回路电流以及阻尼绕组电流等。在此基础上研究了负序磁场中励磁短路线圈的匝数、节距以及短路点过渡电阻等因素对励磁短路电流的影响,并粗略地计算了短路点的发热量。研究结果可为发电机经历恶劣工况后的励磁匝间短路故障的维修提供可靠的决策支持。The rotor windings inter-turn short circuit fault is one of the common faults in turbine generator.When a generator runs in asymmetric condition emerging negative sequence magnetic field,the deterioration rate of inter-turn short circuit fault in rotor windings can be accelerated.In this paper,a 300 MW turbine generator running under asymmetric operation was studied as an example.Considering damping system,the variations of generator fault characteristics after rotor winding inter-turn short circuit were studied,including rotor current,rotor winding induced electromotive force,short circuit loop current and damping current.What’s more,the influences of rotor short circuit coil turns and pitch and short-circuit point transition resistance under negative sequence magnetic field on the rotor short current were studied,also the heating condition of the short circuit point was roughly analyzed.The results provided a reliable decision support for repairing inter-turn short circuit in rotor winding after a generator experienced bad operating conditions.

关 键 词：同步发电机 负序磁场 转子绕组 阻尼系统 过渡电阻 

分 类 号：TM31[电气工程—电机]