N. Jordan Jameson, 1, Michael H. Azarian, 1, and Michael Pecht 1
1 Center for Advanced Life Cycle Engineering, University of Maryland at College Park, College Park, MD 20742, USA
Impedance monitoring of electromagnetic coils is a means of monitoring insulation degradation, a major cause of failures of these coils. This paper develops an equivalent circuit model aimed at identifying diagnostic and prognostic features in the coil impedance frequency response that can be leveraged into a health-monitoring scheme. To identify impedance and frequency components that provide the greatest correlation with insulation degradation, a sensitivity analysis was performed and compared with experimental data. In contrast to previous research, the results reveal features in the impedance spectrum that are more sensitive to insulation health than the coil resonant frequency.