Research on Active Control of Electromagnetic Linear Suspension
In order to improve the dynamic characteristics of electromagnetic linear suspension using lin-ear motors as actuators,an active control strategy consisting of a main loop and an inner loop is proposed.Among them,the main loop uses LQG control optimized by particle swarm optimization algorithm to calcu-late the ideal active force;The inner loop adopts a direct thrust control strategy based on space voltage vector modulation(SVPWM)technology to track the ideal active force.A dynamic model of electromagnet-ic suspension and a mathematical model of linear motor were established,and the correctness of the mathematical model of linear motor was verified through experiments.At the same time,in order to reduce the magnetic flux and electromagnetic thrust fluctuations in traditional direct thrust control,a dual closed-loop controller with magnetic flux and electromagnetic thrust is used to replace the hysteresis comparator,and a SVPWM module is used instead of the switch selection module.On this basis,a speed loop sliding mode controller was designed to improve the control characteristics of the motor system in response to the shortcomings of poor robustness and low accuracy of the PI controller.Finally,simulation analysis was conducted on the motor control performance and suspension dynamic characteristics.The results showed that compared to the no control strategy,the designed active control strategy reduced the electromagnetic linear suspension's body acceleration,suspension dynamic deflection,and tire dynamic load by 21.8％,9.8％,and 17.6％,respectively,effectively improving the suspension's dynamic characteristics.
Electromagnetic suspensionLinear motorActive control
万方数据
维普
