| Switched reluctance motor(SRM)has the advantages of simple structure,high mechanical strength,wide speed range,etc.Its industrial products have been widely used in various fields such as automotive,aerospace and mining.The operation of the switched reluctance motor follows the principle of "minimum reluctance",but due to its unique double salient pole structure and switch power supply method,the magnetic attraction between the stator and the rotor is very uneven,so that the switched reluctance motor always has a large torque ripple.Shortcomings.Therefore,the suppression of torque ripple has always been a hot research direction for international scholars on switched reluctance motors.According to the advantages and disadvantages of torque ripple suppression control strategies commonly used at home and abroad,this paper chooses to focus on direct instantaneous torque control.This article first introduces the basic structural characteristics and working principle characteristics of SRM.The mathematical model of the switched reluctance motor is established,and the three most basic control methods of SRM are analyzed.The working principle of the SRM direct instantaneous torque control strategy and the working process of the power converter in the control process are analyzed in detail.Advantages and improvement directions of torque control.Secondly,based on the analysis of the torque characteristics of the wide speed range and the torque characteristics of the commutation area when SRM is performing direct instantaneous torque control,an SRM direct instantaneous torque control strategy for dynamic regulation of DC-Link voltage proposed.This control strategy based on Cuk converter to optimize asymmetric half-bridge power converter.The adjustable voltage power converter can provide SRM with adjustable adjustable excitation voltage and adjustable adjustable demagnetization voltage to solve the problems of large SRM low-speed excitation current change rate,insufficient high-speed excitation current and insufficient demagnetization voltage.According to the voltage output characteristics of the adjustable voltage power converter,a new direct instantaneous torque control method proposed in combination with the turn-on angle optimization method.The working mode is simplified to increase the interval current and other interval single-phase instantaneous torque control process,which ensures the control of excitation current and instantaneous torque pulsation in wide speed rangeThirdly,aiming at the problem of torque ripple during load change in the SRM direct instantaneous torque control strategy of DC-Link voltage dynamic regulation,a speed loop controller based on ADRC is designed.Perturbations such as system load changes observed and compensated real time,which improves the dynamic performance and anti-disturbance capability of SRM direct instantaneous torque control.Finally,a simulation model of SRM direct instantaneous torque control for dynamic regulation of DC-Link voltage built in Matlab / Simulink,an experimental platform was set up and a controller application program was designed to verify and analyze the control strategy.The simulation results show that the proposed control strategy has good current control effect,can reduce system torque ripple over a wide speed range,has strong anti-disturbance ability,improves the control performance of SRM,and verifies the theoretical value and effectiveness. |
