Design And Control Of Printed Permanent Magnet Synchronous Motor

Compared with the traditional radial permanent magnet synchronous motor,the disc type permanent magnet synchronous motor has the advantages of light weight,short axial distance and large output torque due to its special structure,and is mainly used in applications where the power density requirement is relatively high.With the advent of new processes,the difficulty of manufacturing disc motors has been gradually reduced,especially in recent years,the improvement of printed circuit board(PCB)production technology has made it possible to use PCBs to manufacture stators of disc motors.This kind of disc permanent magnet synchronous motor is also called printed permanent magnet synchronous motor.Since the stator of such motor is composed of PCB printed boards,the printed permanent magnet synchronous motor does not have a stator core,therefore there is no cogging torque.And this kind of winding is especially suitable for mass production.Research on printed permanent magnet synchronous motors has attracted much attention from domestic and foreign scholars.Firstly,this dissertation analyzes several different structures of traditional disc-type permanent-magnet synchronous motors,and selects the single-stator single-rotor disc motor as the research object.Then,the magnetic circuit of the single-gap structure disk motor is simplified with the most favorable magnetic steel inner and outer diameter ratios are obtained.The feasibility of making stator windings of disk-type permanent magnet motors using PCB boards is discussed.Then the electromagnetic characteristics of magnetomotive force,counter electromotive force and output torque of two different structures of spiral windings and wave windings are analyzed.Therefore,a waveform winding structure suitable for printing a permanent magnet synchronous motor is selected.Aiming at the problem of the low utilization rate of printed circuit board(PCB)printed circuit motor with waveform winding structure,a novel wave winding routing method is proposed,which greatly improves the utilization of PCB board.Finally,the designed printed permanent-magnet synchronous motor was simulated by finite element software,and compared with the traditional spiral-wound permanent magnet synchronous motor,and the designed waveform was verified by finite element software simulation.The effectiveness of the winding.Combined with the characteristics of printed permanent magnet synchronous motor,a vector control strategy with i_d=0 is adopted.In order to solve the problem of current interruption and torque ripple caused by the small inductance of the permanent magnet synchronous motor,a scheme of using the external series inductance to compensate the winding phase inductance is proposed.A phase current sampling sampling method based on MOSFET junction resistance is proposed.The principle,technical difficulties and implementation scheme of this method are discussed.Using Matlab/Simulink software,the control simulation model of the motor was built,and the effectiveness of the above control scheme was verified by simulation.Finally,according to the design parameters,the prototype of the printed permanent magnet synchronous motor was fabricated.The parameters such as resistance and phase inductance of the prototype and the back EMF at different rotating speeds were tested.The experimental results are consistent with the theoretical calculations.The vector control of the printed permanent magnet synchronous motor was carried out and the control platform for the printed permanent magnet synchronous motor was built.The phase current waveforms of the prototype before and after the series inductance between the three-phase stator winding and the inverter are compared to solve the problem of current interruption.In addition,the hardware design and preliminary experiment of phase current sampling with MOSFET junction resistance are also carried out in this paper.