1000MW发电机出口半绝缘电压互感器交流耐压试验方法研究

Research on AC Withstand Voltage Test Method of Semi-insulation Voltage Transformer of 1000MW Generator Export

对1000MW火力发电机组的发电机出口浇筑型电磁式电压互感器(简称PT)进行交流耐压试验时,因为PT变比较大且单个二次绕组对一次绕组、其他二次绕组及地的电容较大,如果采用传统的三倍频感应耐压试验,其二次绕组很容易过载,解决办法有两个:其一可以采用电抗器并联补偿的方式减少流过二次绕组的电流;其二采用串联谐振装置直接从一次侧加压。

When conducting AC withstand voltage test on the cast in electromagnetic voltage transformer(PT)at the generator outlet of 1000MW thermal power generation unit,because the PT transformer is relatively large and the capacitance of a single secondary winding to the primary winding,other secondary windings and the ground is relatively large,if the traditional triple frequency induction withstand voltage test is adopted,its secondary winding is easy to overload.There are two solutions:The shunt compensation of reactors can be used to reduce the current flowing through the secondary winding;The series resonant device is used to pressurize directly from the primary side.