Title :
An on-line groundwall and phase to phase insulation quality assessment technique for AC machine stator windings
Author :
Sang Bin Lee ; Jinkyu Yang
Author_Institution :
Dept. of Electr. Eng., Korea Univ., Seoul, South Korea
Abstract :
An on-line technique for monitoring the condition of groundwall (GW) and phase-to-phase (PP) insulation for 3 phase AC machine stator windings is proposed in this paper. Insulation condition indicators such as capacitance, dissipation factor (tanδ), and AC insulation resistance are calculated on-line based on the differential leakage current measurements for each phase. A model for a 3 phase AC machine insulation system is derived and analyzed for both off-line and on-line testing. Guidelines for interpreting the measured indicators for determining the 1) overall condition and 2) significant degradation for the individual GW and PP insulation for each phase of the stator are given based on the analysis. Experimental results on a 15 hp induction motor under intentional GW and PP insulation degradation conditions show that incipient insulation degradation can be detected and classified with high sensitivity.
Keywords :
AC machines; condition monitoring; electric current measurement; fault diagnosis; insulation testing; leakage currents; machine insulation; machine testing; stators; AC insulation resistance; AC machine insulation testing; AC machine stator windings; capacitance; dissipation factor; fault diagnosis; insulation degradation; insulation quality assessment technique; leakage current measurements; on-line condition monitoring; phase-to-phase insulation; AC machines; Capacitance; Condition monitoring; Degradation; Electrical resistance measurement; Insulation; Leakage current; Phase measurement; Quality assessment; Stator windings;
Conference_Titel :
Industry Applications Conference, 2005. Fourtieth IAS Annual Meeting. Conference Record of the 2005
Print_ISBN :
0-7803-9208-6
DOI :
10.1109/IAS.2005.1518285