Permanent Magnet Motors Capable of Pole Changing and Three-Torque-Production Mode using Magnetization

Abstract

Energy saving in electrical appliances and electric vehicles can be realized by reducing the power consumption of their motors, which operate at variable speeds. In order to reduce reducing the energy consumption of electrical appliances, flux-weakening currents are used to reduce the voltage at high speeds, which leads to significant copper and core losses. To counter this problem, we developed a new technique that changes the number of poles and components of torque production in a permanent magnet (PM) motor based on rotational speed. In this study, we propose a novel motor that changes the poles and torque components, and also explain its principles and basic characteristics. The results of our study show that a PM motor can vary the induced voltage from 53% to 100%, operate a three-torque-production mode through magnetization, and reduce core loss by 21%. Thus, the results of our analysis prove that the proposed motor can change the poles and torque components, and can be utilized to achieve high performance and efficiency in variable speed drive systems.