磁浮车辆起浮参数控制及其动力性能研究

Control of levitation parameters and dynamic performance of maglev vehicle

磁浮车辆的起浮性能是磁浮交通系统研究的一个重要方向。为探究控制参数在磁浮车辆起浮过程中对起浮稳定性与振动舒适性的影响,通过建立单悬浮刚性电磁铁模型,从PD控制下的电磁力出发,推导电磁铁起浮过程中动力响应的特征与表达式。由起浮稳定性条件与振动舒适性要求,得到悬浮间隙反馈系数KP的上下限值。将获得的PD控制参数分别应用于单悬浮刚性电磁铁模型、单悬浮弹性电磁铁模型、单悬浮弹性电磁铁—轨道梁模型以及整车—轨道梁模型中,分析起浮过程中电磁铁或车体的位移和加速度响应以及轨道梁跨中加速度响应。研究结果表明:电磁控制参数KP和KD分别调控了起浮过程中系统的刚度和阻尼;KP具有上下限值,下限由电磁铁物理参数及承担质量确定,以抑制起浮失稳现象,上限值由加速度限值、初始位移、额定悬浮间隙、电磁铁物理参数及承担质量共同确定以保证满足规范所要求的振动舒适性;起浮过程中,二系悬挂可以降低电磁铁或车体的加速度,但增大了磁浮架的振动加速度;对于所研究的案例,车轨耦合振动频率较低的情形下,轨道梁对电磁铁或车体的起浮振动影响较小。

The levitation performance of maglev trains is an important research direction of the maglev transportation system.To investigate the influence of control parameters on floating stability and vibration comfort during the levitation of maglev vehicles,a single-suspension rigid electromagnet model was established.Under PD control,the dynamic response characteristics and expressions of the electromagnet during levitation were obtained.The upper and lower limitations of the suspension gap feedback coefficient KP were obtained through the suspension stability condition and the vibration comfort requirement.The obtained control PD parameters were applied to the single-suspension rigid electromagnet model,the single suspension elastic electromagnet model,the single suspension elastic electromagnet-track beam model,the maglev train-track beam model.The vertical displacement and acceleration of the electromagnet or the vehicle body and the acceleration of the track beam were analyzed during levitation.The results show that the electromagnetic control parameters KP and KD regulate the stiffness and damping of the system during the floatation process,respectively.The lower limit is determined by the physical parameters of the electromagnet and the bearing mass to suppress the floatation instability,while the upper limit is determined by the acceleration limit,the initial displacement,the rated suspension gap,the physical parameters of the electromagnet and the bearing mass to ensure that the vibration comfort required by the specification is met.During levitation,the secondary suspension can reduce the acceleration of the electromagnet or the vehicle body,but increase the vibration acceleration of the maglev frame.In the case of low frequency of vehicle-rail coupling vibration,the track beam has little effect on the levitation vibration of the electromagnet or the train.