发电机定子局部放电检测中励磁干扰耦合规律的研究  

RESEARCH ON COUPLING MECHANISM OF EXCITATION INTERFERENCE DURING PARTIAL DISCHARGE DETECTION OF GENERATOR STATOR

作　　者：程养春[1] 李成榕[1] 王伟[1] 林耀洲[1] 

机构地区：[1]华北电力大学电气工程学院

出　　处：《电网技术》2005年第3期50-54,共5页Power System Technology

摘　　要：发电机定子局部放电在线监测的技术关键之一是将定子局部放电信号与噪声信号区别开来,在线监测中会遇到许多干扰,其中包括来自励磁系统的脉冲干扰。作者通过在小型发电机上进行耦合试验,研究了励磁系统中整流元件的脉冲和转子滑环火花放电脉冲通过励磁绕组向定子电枢绕组耦合的规律,分析得出了这类脉冲干扰在励磁绕组与电枢绕组之间的电场和磁场耦合机理,认为低频脉冲干扰通过磁场耦合进入电枢绕组,现场试验结果证实了这一结论。A key technique of on-line partial discharge detection of generator's stator winding is to distinguish partial discharge signal of stator winding from noise signal, and various interference including the pulse interference from excitation system,. may be met during the on-line partial discharge monitoring. On the basis of the coupling test with small-scale generator, the rules that pulse interference from rectifying component of excitation system and' sparkle discharge of slip-ring in rotor are coupled into armature winding through excitation winding are researched. After analyzing above coupling rules, the electric filed coupling mechanism and magnetic field coupling mechanism between excitation winding and armature winding for these kinds of pulse interference are found out, and low frequency pulse interference is coupled into armature winding by magnetic field. This conclusion is verified by on-site test.

关 键 词：大型发电机 定子 局部放电 检测 励磁系统 励磁干扰 耦合规律 脉冲干扰 

分 类 号：TM31[电气工程—电机]