核电站无刷励磁系统的电枢电流谐波分析研究

Analysis on Harmonic of Armature Current for Brushless Excitation System of Nuclear Plant

摘要:

无刷励磁系统是核电站汽轮发电机组的重要组成部分。无刷励磁系统的旋转整流器同转子一起旋转时，旋 转整流器由于承受着强离心力的作用会出现各种故障，而不同故障时电枢电流的谐波是不同的。针对六相无刷励磁 系统励磁机旋转整流器在正常运行、一臂开路和一臂短路 3 种情况下的电枢电流谐波进行理论分析，并在 Matlab 中 Simulink 的环境下搭建三相、六相无刷系统进行仿真分析。通过与三相无刷励磁系统进行比较，得出六相无刷励磁系 统的故障特征与三相无刷励磁系统相似，三相无刷励磁系统故障检测方法可以用于六相无刷励磁系统。

Abstract:

Brushless excitation system is an important part of turbine － generator unit in nuclear plants． When the rotating rectifier of brushless excitation system rotates with the rotor together，there will be some different failures because the rotating rectifier bears a strong centrifugal force，and the harmonic of armature current of different failures is different． The harmonic of armature current is analyzed theoretically aiming at three conditions，that is，exciter rotating rectifier of six phase brushless excitation system in normal operation，one arm open and one arm to be short circuit． The three － phase and six － phase brushless system are established in Matlab /Simulink for simulation analysis． Through comparing with three － phase brushless excitation system，it is concluded that the fault characteristics of six － phase brushless excitation system are similar to three － phase brushless excitation system． So the fault detection method of three － phase brushless excitation system can be used for six － phase brushless excitation system．