I still find it amazing that people are coming out with the same thing that we came out with in the 1990s when PWM drives made their dramatic push into industry – and presenting it all as somehow ‘new.’ In any case, here is another IEEE Electrical Insulation Conference paper published in 1997 from research I initially published in book form in 1995.
Abstract: It is necessary to present a motor repair specification for the repair of low voltage polyphase induction motors intended for PWM inverter application. The specification must approach electric motor repair from the standpoint of maintaining efficiency, not damaging the electromechanical components of the machine, and improving the insulation system. Through the use of the specification, an electric motor should be able to withstand most inverter duty environments upon completion of repair and commission. The purpose of this paper is to present a recommended repair specification meant to reduce the chance of inverter duty failure on repaired low voltage polyphase induction motors.
penrose-low-voltage-inverter