笼型异步电动机转子断条检测的一种新方法

本文提出一种检测异步电机笼型转子断条的新方法。该方法是基于转子断条时气隙磁场中存在脉振分量这一事实。转子断条时 ,气隙磁场可看作是一个圆形旋转磁场和一个脉振磁场的叠加。在定子铁心上放置一个节距为二倍极距的探测线圈 ,即可探测脉振磁场的存在。该方法中转子既不通电也不转动 ,给使用带来方便。实验证明该方法简单有效 ,灵敏度高。

New Method for Detection of Broken Bars in Induction Motors

A new method and apparatus for detection of broken bars in the rotor of squirrel-cage induction motor are described. The test method is easy to implement, no electrical connections need be made to the rotor, and it is no necessary to run the rotor. The effect of the broken bar is modeled as imaginary current in a direction opposite to the current if were intact and a corresponding returning imaginary current in the bars. Sensing coils encompassing 180 degree are examined and the coil is wound in the slots near the gap. The main signal induced in the coils is greatest when the broken bar is near the edge of the sensing coils. A test apparatus with 4 pole 36 slots was constructed and results of measurement on a rotor with 31 intact and 1 broken bar are presented.