Induction motors mechanical failure: influence of the converter on torque pulsation

The aim of this paper is a study of the induction motor mechanical wear when it is used in a variable speed drive: the influence of the inverter output voltage harmonics are particularly taken into account. There are three causes of mechanical wear: induction motor mechanical structure, supply voltage type influence, and load type influence. The authors study only classical induction motor structures. They study the supply type which minimises mechanical wear. The study is in two parts: firstly the authors study the most common converter output voltage waveforms which influence the electromagnetic torque, and secondly, they study the electromagnetic torque pulsation repercussions on the motor reliability