| Switched reluctance motor(SRM)has great development potential for its simple and robust structure,wide speed range,flexible control system and high reliability.However,the torque ripple of SRM is more serious during the phase winding current commutation because of its doubly salient structure and the characteristic of high nonlinearity of the magnetic properties.In this paper,the suppression of torque ripple is considered as the research goal,and torque ripple suppression of switched reluctance motor is realized by studying the control strategy.Firstly,the double salient pole structure and working principle of the switched reluctance motor are studied.Based on the mathematical model of the motor,the simulation model of motor ontology is built.Aiming at the nonlinear characteristic of the motor and the large torque ripple,the fuzzy control and the direct torque control technology are combined.Based on the basic principle of direct torque control,a fuzzy flux linkage controller is designed,and a direct torque control system of switched reluctance motor based on fuzzy flux linkage controller is built.The simulation results show that the fuzzy flux adaptive speed control system can reduce the torque ripple while also reducing the stator current,thus reducing the motor copper consumption.In addition,in view of the problem that the torque ripple of the switched reluctance motor is large in the current commutation range,the torque distribution function is studied and designed,and the control system based on the torque distribution strategy is set up to effectively restrain the torque ripple.Turn-on and turn-off angle are important parameters which affect the torque ripple of switched reluctance motor.To meet the dynamic performance requirements of the system and enhance the robustness of the system,fuzzy logic is used to optimize the turn-on and turn-off angles.And this method achieves the non-linear change of turn-on angle and turn-off angle.Simulation results show that the control method based on fuzzy switching angle has a good effect on the torque ripple suppression compared with the fixed switching angle torque distribution control method.In this paper,a 11 kW three-phase 12/8-pole switched reluctance motor as the research object,the control system hardware platform is built,the software control system process is designed,and the DSP program is prepared.The experimental results show that the control method can effectively suppress the torque ripple.The comparison between the simulation and the experiment shows that the content of this paper is reasonable and effective. |
