Research On Modeling And Simulation Of New Type Brushless Dc Motor

Brushless DC motor is developed on the basis of permanent magnet DC motor retaining many good characters of DC motor and solving the drawback of DC motor produced by machinery commutation, but also has the problems of torque ripple and the inherent weakness of AC motor.In view of this, a new kind of brushless DC motor modeling with theoretical breakthrough and key technical innovation was established against the weakness of permanent magnet DC motor depending on mechanical communication system to complete mechanical communication and the problems of torque ripple and obvious AC characteristics of brushless DC motor, started from the motor structure, combined with the armature winding structure of permanent magnet DC motor and electronic commutation circuit of brushless DC motor, focused on solving the obvious problem of commutation torque ripple of the traditional brushless DC motor, discussed on the key technical of theoretical modeling, the armature winding structure, electronic commutation circuit and communication torque ripple on the basis of motor principles. This new motor could realize the advantages of permanent magnet DC motors and brushless DC motor and overcome the defects of permanent magnet DC motors and brushless DC motor.The main contents of this thesis are as follows:mathematical model of a new kind of brushless DC motor were presented. Simple and practical armature winding structure and electronic commutation circuit were designed. Its torque ripple and the coil components’ communication current expression were deduced, and the discipline of the effect on the motor performance caused by different combinations of the numbers of stator slots and the pair numbers of rotor permanent magnet poles were discussed. Finally, simulation modeling of this new brushless DC motor and traditional DC motor were established in MATLAB/SIMULINK. The current waveform and the electromagnetic torque waveform were compared to find out the pros and cons of the two motors’ performance.Simulation results show that this new kind of brushless DC motor solves the problems of machinery commutation of DC motor and the problems of torque ripple of brushless DC motor.