Title :
Diagnosis of stator winding insulation of large generator based on partial discharge measurement
Author :
Yue, Bo ; Chen, Xiaolin ; Cheng, Yonghong ; Song, Jiancheng ; Xie, Hengkun
Author_Institution :
State Key Lab. of Electr. Insulation & Power Equip., Xi´´an Jiaotong Univ., China
fDate :
6/1/2006 12:00:00 AM
Abstract :
The Stator winding insulation is aged by exposure to a combination of thermal, electrical, mechanical, and environmental stresses. Diagnosis of stator winding insulation is an important measure of ensuring the safe operation and extending the remaining life of large generator. In the paper, two new parameters are proposed for the diagnosis of stator winding insulation based on the test results of multistress accelerating aging test of stator bars. The test results show that the skewness of partial discharge phase resolved distribution and the high-frequency crest of partial discharge (PD) impulse change much more remarkably with the aging time than do the conventional parameters. Therefore, the two parameters could be considered as characteristic parameters for the diagnosis of stator winding insulation of the large generator. With these characteristic parameters, authors successfully assessed the insulation condition of actual stator bars removed from several large generators.
Keywords :
electric generators; machine insulation; machine testing; partial discharge measurement; stators; thermal stresses; electrical stress; environmental stress; large generator remaining life; mechanical stress; partial discharge measurement; stator winding insulation diagnosis; thermal stress; Accelerated aging; Character generation; Dielectrics and electrical insulation; Insulation testing; Life estimation; Partial discharge measurement; Partial discharges; Stator bars; Stator windings; Thermal stresses; Diagnosis; generator; partial discharge; stator bar insulation;
Journal_Title :
Energy Conversion, IEEE Transactions on
DOI :
10.1109/TEC.2006.874223