Estimating induction motor efficiency under no-controlled conditions in the presences of unbalanced and harmonics voltages

This paper presents the application of a method to determine the output power, losses, and efficiency of induction motors, working in no-controlled conditions, in the presences of unbalanced and harmonics voltages. The method uses the steady state equivalent circuits, with some considerations for the analysis of motor performance, fed with unbalanced and harmonic voltages. The parameters of circuits are determined with low invasiveness, by applying a Bacterial Foraging Algorithm as technique of evolutionary search. With this, the efficiency and other operational parameters can be estimated at any operating point. The method was tested in a 12.6 kW motor working in an industrial network, with harmonics and voltage unbalanced.