Design And Analysis Of Permanent Magnet Synchronous Motor For Electric Bicycle Drive

As an important part of vehicle system of China,E-bike has a large market.Among them,Pedelecs have begun to enter people's field of vision as a new green transportation tool,which has huge environmental protection value and broad market prospects.Therefore,it is particularly important to develop high-performance,low-cost drive motors for Pedelec.IPMSM are increasingly used in the field of vehicle drive motors because of high power density,high torque density,high efficiency,high reliability,and excellent field weakening and speed expansion capabilities.Therefore,this thesis chooses the IPMSM as the central drive motor of the moped,and designs and analyzes the central drive motor.Firstly,this thesis introduce the development status of mid-mounted motors for Pedelec,and shows that the research and development of high-performance,low-cost mid-mounted drive motors for bicycles has great application value and broad market prospects.Compare and analyze the different power assist solutions for Pedelecs currently on the market,highlighting the advantages of low cost and good reliability based on the sprocket-type torque sensor power assistance solution.According to the performance requirements of the motor's low torque ripple and wide speed range of the sprocket-type torque sensor power assistance program,this thesis makes a literature investigation and review on the research status of permanent magnet motor in the two fields of restraining output torque fluctuation and improving the range of flux weakening speed regulation with constant power.Secondly,the relevant national standards at home and abroad are investigated to guide the determination of the power performance index of the motor.The maximum torque,maximum power and maximum rotational speed of the drive motor are determined according to the parameters and power requirements of the electric two-wheeler.The basic structure of the motor is selected based on the target of small size,high torque and high power density,and the drive motor is designed preliminarily.Then to establish the mathematical model of the IPMSM,and optimize the design of the motor based on the low torque ripple and wide speed range.To derive the principle of cogging torque and torque ripple generation,and optimize the motor stator and rotor size parameters,adopt uneven air gap to restrain the cogging torque and ripple torque of the motor.Analyze the influencing factors of the permanent magnet motor's field weakening performance from the principle of field weakening control,analyze the influence of the built-in inline permanent magnet motor rotor structure parameters on the field weakening performance,and comprehensively drive the motor's maximum torque,maximum speed and peak power requirements Determine the rotor parameters of the built-in inline permanent magnet motor that meet the operating conditions of the moped.Finally,to calculate the loss and efficiency of the determined drive motor scheme,and check the motor temperature field and the vibration and noise of the motor stator part by software simulation.After the software simulation check,to make the prototype,build prototype test bench,and test the prototype to verify the accuracy of the finite element simulation and check results.Compare the mid-mounted motor designed in this paper with the mid-mounted motor for Yamaha pedelec,highlighting the high-performance and low-cost advantages of the mid-mounted motor designed in this paper...