Analysis of fault signatures for the diagnosis of induction motors fed by voltage source inverters using ANOVA and additive models

Condition monitoring of voltage source inverters-fed induction motors is challenging since the influence of the supply complicates the use of methods valid for utility fed motors. Analysis of variance is performed over data obtained in a controlled laboratory experiment where a hole was progressively drilled into a rotor bar. Additive models are obtained to stand out the influence of the operating conditions and the supply on the amplitude of the fault signatures. Useful conclusions for the design of diagnosis systems for the detection of broken bars in induction motors are drawn from the analysis.