Comparison of two optimization techniques as applied to three-phase induction motor design

In order to develop the best method for the optimization of three-phase induction motor designs, two advanced optimization techniques, the method of boundary search along active constraints and the Han-Powell method, have been compared as applied to a 5 hp three-phase induction motor design. The relations between the optimal efficiency and the material cost, the power factor, the starting torque ratio, and the type of steel have been studied. The limited validity of motor model law is discussed based on extensive calculations. For the 5 hp motor under investigation the Han-Powell method results in a higher maximum efficiency than the method of boundary-search along active constraints. However, the latter method provides a clear visualization of the relations between the motor dimensions and the motor performance characteristics through plotting the results in planes, and it is very useful in the analysis of induction motor optimization from an engineering point of view