Research On Hybrid Optimal Design And The Development Of CAD For Asynchronous Motor

Optimal design of electric machine is a complex nonlinear programming problem with constraint, multi-objective, multi-variable and multi-peak, due to the complication of the design process. It has important practical significance to improving the performance of three-phase asynchronous motor, because they are widely applied in every industry. Therefore, it is a research focus how to realize the efficient optimization design of the three-phase asynchronous motor, with the goal of improving the performance of the motors or reducing costs. To solve the global optimization problem, this thesis presents a hybridize optimization to the parameters of motor, combined improved genetic algorithm with random algorithm. And then software development on the optimization design of small and medium sized three-phase asynchronous motor utilizing VB visual programming technology is completed. The main work is as follows.Firstly, this thesis proposes a new optimization hybrid algorithm based on genetic algorithm(GA) and random algorithm(RA), where fitness function transformation is introduced to avoid the appearance of premature and stagnation behavior caused by inconspicuous fitness gap in the last runs of GA. At the same time the adaptive formula of crossover and mutation probability are adopted to alleviate the main conflict of the population diversity with the convergence speed of GA. In addition, RA is applied to optimize the optimized results of GA to avoid the discrete error caused by binary-coded genetic algorithm and improve performance in local range due to the uncertainty of genetic operation rules. Test results show the algorithm is feasible and effective.Secondly, mathematical analysis and processing method are studied in the optimization design of three-phase asynchronous motor. In this section, the optimization mathematical model is established for the three-phase asynchronous motor. The way of data storage and method of numerical calculation have been analyzed.Thirdly, motor design program and optimization program are developed under the development tools provided by VB according to the motor design theory and optimization algorithm. And the corresponding program flow chart is also described.Finally, on the basis of the interface design, the perfection of optimization design software of the three-phase asynchronous motor has been completed, which is applied to the optimal design of three-phase asynchronous motor. The results of the optimization design show that the designed software can realize the optimization design of the three-phase asynchronous motor and improve motor’s performance.