Abstract

Frequency inverters are largely used as induction motor drives, so that a linear model for the torque of an induction motor can be useful for making computational simulations about that control technique. This paper propose to develop a model for a torque of an induction motor based on the torque versus speed characteristic, using the linearization method applied in a specific operating range, which normally work the frequency inverters. This model becomes interesting for evaluating the performance and calculating parameters of the motor, when it’s driven by the frequency inverter. From a specific expression for the torque versus speed, the application of the linearization method leads to a linear expression to the torque relating the induction motor parameters. The validation of this linear model is obtained comparing with some original torque curves of the induction motor given by manufacturers. Results showed accordance with curves values in the range of interest.

Key words: Induction motors, linearization methods, mathematical models.