Research on Insulation Damp Diagnosis of Synchronous Motor Stator Winding

The insulation of synchronous motor is easily affected by its operation state and structure. Because the insulation of synchronous motor can only use solid insulation medium, which is embedded in the core groove, it can not be immersed in insulating oil like transformer, nor can it be sealed in metal shell full of SF6 like GIS, and the insulation of synchronous motor can only be exposed to air. In some cases, it is easy for the winding to get damp. In this paper, the frequency-domain dielectric spectroscopy method is used to detect the moisture of stator winding. The test results of several groups of samples are compared, and the cause analysis is given.