Research On Design Of Disk Permanent Magnet Brushless DC Motor

The disc permanent magnet brushless DC motor(DPMDBM) has a simple structure, reliable operation, convenient maintenance, axial compact structure, and stepless speed regulation and so on. Compared with traditional motors, The disc permanent magnet brushless DC motor whose air gap is flat and the air-gap magnetic field is axial, can be designed to have a high torque - inertia ratio and power density, in particular coreless motor which has no eddy current and hysteresis loss, energy-saving results are obvious. The DPMDBM is widely used and has a broad application prospects. in electric vehicles, high-level household appliances, wind power generation, petroleum and chemical industry .The design of permanent magnet synchronous servo motor was researched systematically in this paper, including design method, finite element analysis, steady state performance computation , tests and so on. The main contents of this thesis are as follows:1,Research status quo,present problems and prospect of DPMDBM were summarized and analysed. Starts with four mainmechanical parameters to design structure dimension of the DPMDBM. Analyses motor's basic electromagnetic relations and design features and obtains a number of guiding significance in design.2,Finite element analysis model of DPMDBM was created by Maxwell 3D. The three-dimensional electromagnetic field of DPMDBM is in-depth investigated in orde to study the magnetic field distribution law and calculate magnetic flux of per pole. The reasults facilitate the design optimization for in-depth research.3,Based on the terminal potential circuit equation of the three-phase full-bridge DPMDBM with wye-connected phase winding and with two transistors conducting at anytime, the analytical expression of the phase current of squre wave and sine wave PMBLDCM was induced by the solution of differential equation, and the steady-state performance allowing for the winding inductance was also simulated and analyzed; A numerical method on basis of making use of Runge-Kutta method solving current state equations of DPMDBM to steady-state performance was discussed.4,Experiment of DPMDBM were carried on,including measure parameters of motor,test of back EMF waveform and magnetic field waveform, operation of motor control and test of performance curves. Test result and design result were compared and analysed. Also the method of design was verified by the test result.