摘要
这种新方法的基础是零序变压器在三相异步电动机断相时输出一个电压信号。经研究发现,零序变压器输出电压与断相点间电压U_(A'A)成正比。当外加电压一定时,各种电机的U_(A'A)在一定范围内变化。所以,这种保护器保护范围广,通用性强;同时,功耗小,价格便宜,很有发展前途。
Use is made of that zero-sequence transformer outputs a voltage signal when phase-failure occurs in three-phase induction motor. It is found that output voltage of zero-sequence transformer is proportional to voltage UA'A between phase-failure points.With constant applied voltage, UA'A for various motors varies in certain range. Therefore, the protector has potential prospects due to its wide range of protection, versatility, low power consumption and low price.
关键词
零序变压器
断相保护
异步电动机
zero-sequence transformer, zero-sequence flux, phase-failure protection, three-phase induction motor.