Method for Estimating a Residual Resource of Induction Motor Winding Insulation Based on Capacitive Leakage Currents

The paper presents an approach to estimating resource expenditure and predicting the induction motors windings insulation residual life based on the measurement of capacitive leakage currents created by a continuous sequence of rectangular voltage pulses. Experiments show an exponential decrease in leakage currents due to the development of insulation degradation processes in the long term. It was proposed to estimate the residual resource value using a modeling exponent, whose parameters are determined in the current time mode using parameter identification methods such as the least squares method (OLS) or methods based on the Kalman algorithm. The advantage of the proposed method is the comparative simplicity of the technical means used and the ability to assess the residual life of the winding insulation, relying only on the data experimentally obtained through measurement. The article describes the operation of the algorithm for the prediction of the insulation condition based on the parameters identification of the modeling exponent.