高压电动机定子绕组绝缘薄弱点的有效定位

针对局部放电检测方法(无论在线还是离线)只能判断一相定子绕组绝缘的放电量,无法定位到绝缘薄弱点的问题,根据局部放电发生时会向周围辐射电磁波和超声波,利用定向天线和超声传感器检测出放电位置和放电强度,并与脉冲电流法检测的幅值和图谱进行比对,从而确定放电位置.根据现场情况,减少噪声、电磁干扰等干扰源对电动机定子绕组局放检测的影响,总结出高压电动机定子绕组声电局放综合检测正常情况、内部放电等情况的参考图形.进行大量现场测试并制定不同类型、不同放电级别的放电点,根据频谱信息验证定位的准确性.声电局放综合检测与脉冲电流检测视在放电量的结合使用,并根据探测器接收的局放信号图谱与脉冲电流检测图谱进行比对,判断高压电机定子绕组不同放电点.通过对高压电动机定子绕组绝缘薄弱点的定位试验, 掌握江都站主电动机绕组的绝缘状况及性能, 为保障机组安全运行以及大型泵站加固改造提供了重要数据.

High voltage motor stator winding insulation vulnerabilities of effective positioning

For partial discharge detection method(no matter online or off-line), it can only be used to determine the discharge capacity of a phase stator winding insulation, which can be used to detect the discharge position and discharge intensity. According to the situation of the field, reduce the noise, electromagnetic interference and other interference sources to the motor stator winding test, summed up the high voltage motor stator winding sound power of the test of the normal situation, internal discharge, etc.. A large number of field tests were carried out to establish the discharge points of different types and different discharge levels, and to carry out the accuracy of the spectrum information and verify the location. The combined detection of the sound and the pulse current is used in combination with the pulse current detection, and the different discharge points of the stator winding of high voltage motor are judged by comparing the signal spectrum and the pulse current detection. The insulation condition and performance of the main motor windings of the main motor of the Jiangdu Railway Station are provided by the positioning test of the weak point of the stator winding insulation of high voltage motor.