Novel Partial Discharge Monitoring Scheme for Rotating Machine

Summary

Authors' early work had introduced a novel on-line partial discharge monitoring sensor CSC (Capacitive Slot Coupler), which frequency band was between 100 kHz and 20 MHz. However, after intensive laboratory work and on-site experiment, it was found that the upper limit frequency of CSC PD sensor could be widely extended from 20 MHz to 250 MHz. In this paper, an equivalent partial discharge detection circuit is introduced considering the various PD sources. And it is also suggested that the novel sensor could be applied to identify the partial discharge sources such as internal discharge, slot discharge and end winding discharge via the concept of OPDC (On-site Partial Discharge Calibration) and TAF (Time of flight analysis, Attenuation ratio analysis in Frequency domain). Furthermore, from the on-site experiment for small motor, it is suggested that the CSC PD sensor could be effectively adopted in discriminating the various external noises and locating PD activities. In addition, the laboratory developed instrument for simultaneous measurement of PD signals obtained from three phases is introduced as the first step for the market production.

Additional informations

Authors

Shao Yingyu, Li Yuquan