Effects of transmission belt looseness on electrical and mechanical measurements of an induction motor

This article explores the impact of belt looseness on electrical and mechanical quantities of a system driven by an induction motor and a belt-pulley transmission. The effects of this defect, for example the belt slipping or the apparition of spectral signatures in some measurements, are first investigated under steady state operation. Transient state tests are then performed to analyse, in the time domain, the system response to a step of the speed reference. The behaviour of different variables (slip, speed, currents, etc.) is studied for different health conditions and the increase of the belt looseness clearly impact the electric and mechanical variables´ waveforms. The experimental tests carried out in this study, under steady or transient state, show promising results for the diagnosis of belt degradations. Perspectives of this work are therefore detailed at the end of this paper.