Title :
Measurement of stress grading conductivity to 1.6 MV/m and 155 oC Computation of grading power density and temperature rise for PWM waveforms
Author :
Boggs, S.A. ; Kumada, A. ; Yoshimitsu, Tetsuo
Author_Institution :
Inst. of Mater. Sci., Univ. of Connecticut, Storrs, CT, USA
Abstract :
The move to PWM-based waveforms with substantial high frequency content results in much greater capacitive currents in the stress grading (SG) material and the conductive armor tape (CAT) which increase power dissipation and electric fields within these elements. Treating this subject numerically is challenging for several reasons, viz., (i) the need to measure SG nonlinear properties as a function of field to at least 1.5 kV/mm over the operating temperature range and (ii) the difficulty of computing steady state temperature rise in a stator bar which results from a continuous PWM waveform. This contribution presents solutions to both problems.
Keywords :
cable sheathing; electrical conductivity measurement; pulse width modulation; stators; waveform analysis; CAT; SG nonlinear properties; capacitive currents; conductive armor tape; conductivity measurement; continuous PWM waveform; electric field effect; grading power density; operating temperature; power dissipation; stator bar; steady state temperature; stress grading materials; temperature 155 degC; Computational modeling; Current measurement; Dielectrics; Electrodes; Materials; Pulse width modulation; Temperature measurement; converter; corona protection; form wound coil; stator endturn; stress grading;
Conference_Titel :
Electrical Insulating Materials (ISEIM), Proceedings of 2014 International Symposium on
Conference_Location :
Niigata
DOI :
10.1109/ISEIM.2014.6870718
