Research Of A Compound Control Of FOPIPFC And Sliding-Mode Variable Structure In Brushless DC Motor

With the advantages of small size,large output torque,high control precision and reliable operation,brushless DC motor(B LD C M)has been widely used in all fields of industry.With the upsurge of new energy electric vehicle and UAV research,how to improve the control performance of Brushless DC motor is worth further research.Aiming at brushless DC motor speed control system,several intelligent control algorithms are proposed in this paper.The working principle of Brushless DC motor control system is analyzed in this paper,aiming at the problem of fractional PI predictive function control(FOPIPFC),the performance degradation,system instability with the mismatch of model,and dithering of sliding mode control.Combining the advantages of the two algorithms and making up for the deficiencies,a new composite control method based on fractional PI prediction and sliding mode variable structure is proposed.Due to the previous FOPIPFC control algorithm,the parameters are selected through experience and multiple experiments.When the controlled object changes,the parameters need to be adjusted again,which is not only time-consuming,but also may affect the control effect because the optimal control parameters can not be found.Therefore,this paper proposes the use of particle swarm optimization algorithm to optimize tuning parameters.The control system simulation is built in the Matlab/Simulink software platform.The speed control loop is a combination of FOPIPFC and sliding mode variable structure.The current loop is controlled by PI.Through simulation,we can observe the control effect of compound control algorithm from aspects of motor speed performance and anti-interference ability.The simulation results show that the composite control algorithm responses quickly,has no overshoot,its anti-interference ability and stability are higher.Finally,based on the DSP320F28335 experimental simulation platform,C language programming is used to realize the FOPIPFC,sliding mode variable structure control and compound control on the motor speed control respectively.The experimental results show that the combination control combines the advantages of the two algorithms,and makes up for their shortcomings and has good control effect.