Effect of multistress on the lifetime characteristics of magnet wires used in flyback transformer

Abstract

This work presents the results of the effect of multistress on the lifetime characteristics of fine gauge magnet wires used in the flyback transformers, adjustable speed drives, motor windings, ignition coils. Accelerated life tests are performed on AWG 43 gauge Polyesterimide insulated magnet wires. This study uses pulse voltages. Multistress includes high temperature, high frequency, and high voltages. Lifetime analysis provides statistical information such as lifetime characteristics, probability of failures, and lifetime percentiles. This study uses Weibull distribution to model life characteristics. The failure data of the aging tests is used to obtain parameters of the frequency-electrical-thermal life model. The life model is used to describe the behavior of insulation in the presence of multistress and is also used to estimate the lifetime of magnet wires at any desired stress level. The parameters of the frequency-electrical-thermal life model used in this study are obtained by regression analysis.