2009 Volume 3 Issue 3 Pages 296-308
A verified hybrid optimization procedure, which combines the genetic algorithm (GA) with traditional optimization methods, is presented in this paper with a disc type piezoelectric motor. The optimization objectives include minimizing the frictional loss of the rotor and maximizing the efficiency and spin speed of the piezoelectric motor. The behavior constraints include spin speed, natural frequency, and stability. The Runge-Kutta method is applied to determine the dynamic response of this motor, and the Floquet theory is employed to analyze the motor's stability. The optimization algorithm (hybrid genetic algorithm, HGA) applies GAs to provide an initial design variables set, thereby avoiding the trial process; thereafter, traditional algorithms are employed to determine optimum results. With the single-objective and multi-objective optimizations by using the HGA, both the efficiency and spin speed of the motor can be improved, and the frictional loss of the coating can be decreased effectively, either individually or simultaneously. The designs of the designated performances can be derived as well.
