Investigation of Partial Discharges at the High Voltage Electric Motor Bars

Abstract

It is well known the use of on-line partial discharge (PD) measurements as an indicator of stator winding insulation condition. The scheduled PD measurements could be used as a test to evaluate the quality of the equipment. The test results could help to diagnose the insulation problems in motors and generators for corresponding action before failure occurs. Although a number of PD measurement methods exists, but the tests results of on operating rotating machines can be influenced by conditions such as humidity, temperature, terminal voltage, and load. This paper describes the development of PD imitation mathematical model in stator insulation. The experimental investigation with physical model was performed for adequacy assessment. The capacitive sensor was used for PD online monitoring.

Two Stage Data Fusion of Acoustic, Electric and Vibration Signals for Diagnosing Faults in Induction Motors

“…Recently several new condition monitoring methods have been developed, which fuse different types of signals in order to achieve better accuracy in identifying faults. It has been observed in multiple works (see for example [1]- [6]) that different signals are most informative for different faults: vibration signals are well suited for monitoring bearing faults [1], [2], current signals are good for detecting problems such as broken rotor bars or eccentricity relatedfaults [1], [3] and capacitor sensors may be used to measure the partial discharges that are indicative of stator winding insulation problems [1], [4].…”