A Study on The Electromagnetic Multi-Step Transmission Characteristics of Interior Permanent Magnet Synchronous Motors

In this paper, electromagnetic multi-step transmissions are introduced as a method for increasing the torque and efficiency of electric vehicle driving motors. Motors using permanent magnets have limited ability in speed back electromotive force increases increases. The motor performs field-weakening controls to increase after rated point. Field-weakening control rotor’s by weakening magnetic flux field. At time, output is constant voltage limits, which also affect maximum motor. order improve these constraints, there case study shifting phenomena. Examples research include wye-delta changing number equivalent serial turns. As previous studies, problem forces solved. we propose parallel paths. lower at high speeds, paths stator windings changed via thyristor. increases, decreases. When lowered, that can be reduced, but lowered. Before shifting, set two satisfy low speeds. After increased 4 with paths, broaden operating range addition, resistance reduced high-speed region. loss accounts largest proportion copper loss, reducing it, increased. result, it area simultaneously high-efficiency area. analyze characteristic, finite-element-method-based simulation was used.