Electromagnetic Design And Simulation Of Double-stator Permanent Magnet Motor Drive For Electric Motorcycle

With the development of electric motorcycle industry, the demand for high-performance drive motor is growing. Double-stator permanent magnet motor with excellent performance is getting more and more attention and research. In this paper, based on the single-stator permanent magnet motor drive for electric motorcycle, a double-stator permanent magnet motor was reported, as a novel structure motor, there are many issues unresolved, so this subject mainly studies on the electromagnetic design and the influence of structure and parameters on the motor performance.Firstly, the thesis briefly introduced the working principle of double-stator permanent magnet motor. The basic structure of the motor, electromagnetic relations, mathematical model, equivalent circuit, voltage equation, power and torque balance relationship was analyzed. Secondly, several common electromagnetic design methods of electric motor were introduced and comparative analyzed. Because of the special structure of double-stator permanent magnet motor, this thesis adopt "Field-circuit coupled" method, after discussing stator size, magnetic circuit, permanent magnet design,winding design, rotor and stator design, the electromagnetic design of the motor was presented, and lists the electromagnetic design parameters. Thirdly, the basic theory and analysis method of electromagnetic field in electric machines was briefly introduced. The finite element model of double-stator permanent magnet motor was established with Ansoft software which was used in electromagnetic field simulation. Different operating conditions of the motor was simulated, including magnetic field analysis, back EMF and flux leakage coefficient calculation at no-load, and the operation performance of double-stator permanent magnet motor in different speeds at rated load and etc. Meanwhile, the single pitch fractional-slot winding research was also carried out,calculating the winding factor and analysis the influence of current on winding inductance. Finally, according to the characteristics of double-stator permanent magnet motor, the influence of motor structure parameters on the performance was studied. By compared with single-stator permanent magnet motor, the influence of adding an inner stator on the output torque, space and material utilization ratio were analyzed. The influence of inside and outside the air gap combination, split ratio and relative position of the inside and outside stator on motor performance was also analyzed, and the method to determine the optimal design of electrical machine is given. Research results show that double-stator permanent magnet motor has higher power density, better starting performance, stronger driving capability, make full use of the interior space, improved the space utilization ratio. Meanwhile, the motor structure parameters has significant influence on the motor performance, the design should be carried out according to the applications and requirements.The high-performance double-stator permanent magnet motor is suitable to electric motorcycle drive motor,in the area of electric vehicle drive has very wide application, and is important in promoting the development and promotion of electric motorcycles.