Open AccessAnalysis of Off-Line and On-Line Partial Discharge in High Voltage Motor Stator Windings
Author(s) -
HeeDong Kim,
TaeSik Kong,
Sang-Kil Lee,
Beom Soo Kim,
Doo-Young Kim
Publication year - 2015
Publication title -
journal of electrical engineering and technology/journal of electrical engineering and technology
Language(s) - English
Resource type - Journals
eISSN - 2093-7423
pISSN - 1975-0102
DOI - 10.5370/jeet.2015.10.3.1086
Subject(s) - stator , partial discharge , electromagnetic coil , line (geometry) , voltage , electrical engineering , universal motor , high voltage , materials science , spare part , terminal (telecommunication) , engineering , ac motor , mechanical engineering , mathematics , telecommunications , geometry
The off-line and on-line partial discharge (PD) in the stator winding of three high-voltage (HV) motors (1,400 HP, 6.6 kV) is measured and analyzed in this paper. The off-line PD is measured at high values between 24,300~36,100 pC after 18 years of motor operation. Spare replacement motors were not available for testing the degree of deterioration of the stator windings in standstill status. Therefore, on-line periodic analysis was conducted to monitor the trend of PD after installing a ceramic sensor (110 pF, 6.6 kV) in the terminal box for each phase of each motor. In the stator winding of the No.1 and No.2 HV motors, which showed high magnitudes of off-line PD and low magnitudes of on-line PD, defects are expected to appear in the neutral end of the winding. On the contrary, in the stator windings of the No.3 HV motor, which exhibits high off-line and on-line PD magnitude, defects are expected to appear in the terminal end of the winding where a voltage close to the phase voltage is applied.