Control System Simulation Research Of The Brushless DC Motor With Drum

The beushless DC motor adopts electronic phase changing instead of mechanical phase changing, which overcomes the disadvantages of the traditional DC motor caused by the brush friction, furthermore, with many advantages such as good functions of speed regulation, little volume and high efficiency, it is widely applied in industry and daily life.This research is the brushless DC motor with drum applied to treadmill, so it is series for the motor control, including the motor speed in response to the situation, the electrical stability of the output torque and its self-control, and so on. In order to research the motor control system more convenient, this paper complete the overall system simulation of the treadmill BLDCM based on Matlab/Simulink platform.Firstly, The paper analyzes the basic configuration of BLDCM control system, and establish the mathematic model with the fundamental principle of the brushless DC motor, the novel simulation model of BLDCM is built based on Matlab/Simulink PSB block to help the characteristics analysis.Secondly, The control system of BLDCM is a nonlinear system, it is difficult to reach exactly control based on traditional control method, the fuzzy PID controller is designed according to the characteristics of the system, Fuzzy control do not rely on a precise mathematical model, and the simulation model of the brushless DC motor is established, based on the fuzzy PID controller, Simulation studies of the starting process, operation process, switch-in and switch-out of load, curves of Rotation speed, torque, current and back-EMF. Meanwhile, curves of rotation speed are carried out, which are got with fuzzy PID, respectively are analyzed. The results of simulation prove the feasibility of the control system and the system control precision is improved.Finally, this paper analyses the producing reason of torque ripple in details, According to the simulation of the actual situation, emphatically introduces the reason of commutation torque ripple suppression techniques. Two methods for reducing commutation torque ripple generated in BLDCM, Current hysterics control and fuzzy PID speed optimization, Effectiveness of the proposed control method is verified through simulation.