Title :
Potential distribution on the stress grading system of high-voltage rotating machines ???I measuring system
Author :
Kumada, Akiko ; Nakamura, Takahiro ; Hidaka, Kunihiko ; Tsuboi, Yuichi ; Yoshimitsu, Tetsuo
Author_Institution :
Dept. of Electr. Eng. & Inf. Syst., Univ. of Tokyo, Tokyo, Japan
fDate :
12/1/2015 12:00:00 AM
Abstract :
A surface potential measuring system has been developed utilizing a Pockels sensor to measure the potential distribution of the stress grading (SG) system of form wound motor coils. A Pockels BGO crystal is positioned just above (<;1 mm) the SG, and the capacitively-induced voltage on the surface of the BGO crystal adjacent to the SG is measured by using Pockels effect of the BGO crystal. The sensing system is applicable to surface potential measurement over wide frequency region from 0.001 Hz to 100 MHz. The spatial resolution of the measuring system after enhancement through deconvolution is discussed with the result that the -3 dB spatial frequency of the measuring system is 0.22 cycle/mm which implies a resolution in the range of 4 mm.
Keywords :
Pockels effect; electric machines; machine insulation; measurement systems; sensors; surface potential; Pockels BGO crystal; Pockels effect; Pockels sensor; SG system; capacitively-induced voltage; frequency 0.001 Hz to 100 MHz; high-voltage rotating machines; stress grading system; surface potential measuring system; wound motor coils; Crystals; Dielectric measurement; Electric potential; Optical surface waves; Stator cores; Surface waves; Pockels sensor; Tikhonov???s regularization; end turn grading;
Journal_Title :
Dielectrics and Electrical Insulation, IEEE Transactions on
DOI :
10.1109/TDEI.2015.005581
