Research On Torque Ripple Reduction Strategy Of Coil-assisted Reluctance BLDCM

It has attracted much attention due to its simple structure,low price and high robustness since the advent of the reluctance type motor.However,the double salient pole structure,strong non-linearity and step-by-step rotation of reluctance motor lead to large torque ripple,which hinders the development of reluctance motor.The coil-assisted reluctance brushless DC motor(CAR-BLDCM)studied in this paper is composed of two groups of stator and rotor salient poles related to poles.The auxiliary coil is added to the center of the motor to provide adjustable magnetic field.This paper proposes a control strategy for CAR-BLDCM to simultaneously adjust the armature winding current and auxiliary coil current.Firstly,the basic topology and working principle of CAR-BLDCM are introduced.The mathematical model of CAR-BLDCM is established.According to the torque formula,changing the auxiliary coil current can effectively adjust the motor torque and achieve the effect of suppressing the motor torque ripple.Secondly,the Torque Sharing Function(TSF)is used to control the armature winding current.The radial basis function(RBF)neural network is used to train the torque-current inverse module offline.The torque ripple caused by poor current tracking performance during motor commutation is reduced by adjusting the auxiliary coil current.Fuzzy PI regulator is used in speed closed loop to improve the fast response and stable operation ability of the motor,and expand the application field of reluctance motor.The simulation platform of CAR-BLDCM control system is built by Maxwell,Simplorer and Simulink.The control strategy proposed in this paper is compared with traditional current chopper control,and analyzed from three aspects: speed,torque and sudden load.The simulation results show that the proposed control strategy not only improves the response speed of the motor,but also effectively reduces the torque ripple of the motor.Finally,the experimental platform of CAR-BLDCM control system is built.The hardware control platform includes power inverter and its drive circuit and position and current detection circuit.The system software design includes the main program,the initial subroutine,and the interrupt subroutine.