Application of search methods in modeling integral horsepower AC motors with microprocessor-based power electronic controllers

An optimum model is found for a three-horsepower AC motor and load controlled by a modern microprocessor-based power electronic controller. The proposed model includes the introduction of an integration term into the linear dynamics as well as two nonlinear terms, one of which depends upon user-selected parameters in the controller. The model form for a particular motor-load combination is optimized by minimizing a performance criterion based upon the difference in speed between test data and data predicted by the model in which parameters are varied. The simulation of the model indicates that in open-loop operation the motor dynamics are typically masked by user-selected controller parameters. A suggested method of operating the actual system allows the motor dynamics to be observed and estimated. Simulation results are compared with test data in both modes