A computer-aided diagnostic system has been designed and developed for the measurement of partial discharge (PD) activity in high-voltage generator insulation. Through a novel software mapping, a high-bandwidth digitizing oscilloscope can be used as a full-feature discharge detector despite a limited memory. The scheme employs an acquisition system which permits real-time data to be accumulated over a complete 60 Hz cycle by a multi-pass algorithm. The arrangement contrasts with many conventional discharge measurement methods which discard, inevitably, much of the information during high voltage tests. A number of noise reduction, manipulation and analysis routines are presented which permit reconstruction of stored data in order to extract many PD-related characteristics; such as the time and frequency of occurrence, the magnitude, and the polarity of the recorded pulses. Use of the method is illustrated by presenting results using data from an experimental research program. A version of the system is also outlined which is suitable for electrically hostile environments where external interference could contaminate the measurement.
[1]
E. Gulski,et al.
Computer-aided recognition of discharge sources
,
1992
.
[2]
T. Okamoto,et al.
Novel Partial Discharge Measurement Computer-Aided Measuremnet Systems
,
1986,
IEEE Transactions on Electrical Insulation.
[3]
J. K. Nelson,et al.
Assessment of deterioration in epoxy/mica machine insulation
,
1992
.
[4]
G.C. Stone,et al.
Digital recording techniques for electrical insulation measurements
,
1989,
IEEE Electrical Insulation Magazine.
[5]
R. Bartnikas,et al.
Digital techniques for partial discharge measurements. Discussion
,
1992
.
[6]
C. Mayoux,et al.
Corona frequency analysis in artificial cavities in epoxy resins
,
1973
.