The Transactions of the Korean Institute of Electrical Engineers C (대한전기학회논문지:전기물성ㆍ응용부문C)

The Korean Institute of Electrical Engineers (대한전기학회)
권호 표지

Analysis of Partial Discharge in High Voltage Motor Model Coils

고압전동기 모델 코일에서 부분방전 분석

  • Published : 2006.04.01
Download PDF
⟨ Previous Next ⟩

Abstract

Five model coils of 6.6 kV motor were manufactured with several defects. These stator coils have artificial defects such as void of groundwall insulation, removal of semi-conductive coating and damage of strand insulation. Epoxy-mica coupler(80 pF) was connected to five model coil terminals. The voltage applied to the coils was 3.81 kV, 4.76 kV, 6.0 kV and 6.6 kV, respectively. Partial discharge(PD) tests performed in the laboratory and shield room. Digital PD detector(PDD) and turbine generator analyzer(TGA) were used to measure PD activity. TGA summarizes each plot with two quantities such as the normalized quantity number(NQN) and the peak PD magnitude(Qm). The PD levels in pC were measured with PDD. PD patterns of model coils were indicated the internal and slot discharges. PD patterns are consistent with the result of measurement using PDD and TGA instruments. AC breakdown test was performed on five model coils in order to confirm the result of PD measurements. All the failures were located in a line-end coil at the exit from the core slot.

Keywords

References

  1. G. Griffith, S. Tucker, J. Milsom and G. C. Stone, 'Problems with Modern Air-Cooled Generator Stator Winding Insulation', IEEE Electrical Insulation Magazine, Vol. 16, No.6, pp. 6-10, 2000 https://doi.org/10.1109/57.887599
  2. IEEE Std 1434-2000, IEEE Trial-Use Guide to the Measurement of Partial Discharges in Rotating Machinery
  3. H. Zhu, V. Green, M. Sasic. and S. Halliburton, 'Increased Sensitivity of Capacitive Couplers for In-Service PD Measurement in Rotating Machines', IEEE Trans. on Energy Conversion, Vol. 14, No.4, pp. 1184-1192, 1999 https://doi.org/10.1109/60.815045
  4. L. Lamarre, D. Jean and Due Ngoc Nguyen, 'Laboratory studies of slot discharges on stator bars', IEEE Conference on Electrical Insulation and Dielectric Phenomena, pp, 490 - 494, 2002 https://doi.org/10.1109/CEIDP.2002.1048841
  5. G. C. Stone, Partial Discharge Seminar, Iris Power Engineering Inc., Vol. 1, pp, 56-78, 2005
  6. 김희동, '회전기 고정자 권선의 절연상태 평가', 대한전기학회 하계학술대회, pp. 1706-1708, 2001
  7. H. G. Sedding, R. Schwabe, D. Levin, J. Stein and B. K. Gupta, 'The Role of AC & DC Hipot Testing in Stator Winding Ageing', IEEE Electrical Insulation Conference, pp. 455-457, 2003