Evaluation of Induction Motor Groundwall Insulation using Infrared Thermography

In this research work, an attempt has been made to study the behavior of medium voltage stator bar specimens that are subjected to steep-front pulse voltage waveforms by using infrared thermography. In this regard, an accelerated aging test is developed by using electrical and thermal stress conditions. The test conditions include; voltage amplitudes up to 3.5 kVp, pulse switching frequencies up to 3000 pps and test temperatures up to 1550C. During the aging process surface temperature profiles are recorded with an infrared camera as a means for determining the highest stress regions. The experimental results show that both the voltage stress and the thermal losses are quantitatively higher with converter supply than in the case of power frequency