高速列车牵引变压器悬挂参数动态优化设计
Dynamic optimization design of hanging parameters for traction transformer of high-speed train

为了优化牵引变压器悬挂参数,建立了车辆设备21自由度刚柔耦合系统模型,并基于新型快速显式数值积分法求解了车辆和牵引变压器的振动响应; 计算了车辆系统在不同速度等级下的舒适度指标和设备振动烈度,确定了变压器最优悬挂频率; 建立了变压器数学模型与车辆设备刚柔耦合模型,结合最优悬挂频率、振动烈度、舒适度指标、隔振器动态作用力以及变压器悬挂模态与车辆地板局部模态匹配指标对隔振器参数在动态条件下进行多目标优化,计算了牵引变压器隔振器最优参数。研究结果表明:当牵引变压器悬挂频率比为0.82～0.98时,车辆舒适度低于2,设备振动烈度低于4.5 mm？s-1,满足相关规范要求; 经过优化最终确定第1组隔振器垂向刚度、三组隔振器刚度比、每组隔振器三向刚度比分别为2 142 N？mm-1、1:1.3:2.5、1.7:0.5:1,与变压器原始悬挂方案相比优化后变压器振动烈度最大降低42%(在速度高于200 km？h-1条件下),车辆一位端、中部、二位端舒适度指标平均提升3.53%、3.45%、2.01%,第1、4隔振器垂向作用力平均降低13.3%,第2、5隔振器垂向作用力平均降低3.8%,第3、6隔振器垂向作用力平均降低20.9%。可见,优化后车辆舒适度、设备振动烈度和隔振器垂向动态作用力均有较好改善。
A vehicle-equipment rigid-flexible coupling system model with 21 degrees of freedom was proposed in order to optimize the hanging parameters of traction transformer. The new and rapid explicit numerical integration method was used to compute the vibration response of the vehicle and traction transformer. The vehicle comfort degree indexes and equipment vibration severities of vehicle system under different speeds were calculated, and the optimal hanging frequency of the transformer was obtained. A mathematical model of the transformer and a rigid-flexible coupling model of vehicle-equipment were set up, the multi-object dynamic optimization was performed on the vibration isolator parameters under considering the optimal hanging frequency, vibration severity, comfort degree index, dynamic force of vibration isolator, and matching index of transformer suspension mode and vehicle floor local mode, and the optimal parameters of vibration isolator in the transformer were computed. Research result indicates that when the suspension frequency ratio of the traction transformer is 0.82-0.92, the vehicle comfort degree index is less than 2, and the vibration severity of the equipment is less than 4.5 mm？s-1, which can satisfy the requirements of related standards. After optimization, the vertical stiffness of the first group isolator, the stiffness ratio of three groups of isolators and the three directions's stiffness ratio of each group of isolators are 2 142 N？mm-1, 1:1.3:2.5 and 1.7:0.5:1, respectively. Compared with the original suspension scheme of the transformer, the vibration severity of equipment decreases by up to 42% at the speed more than 200 km？h-1, the comfort degree indexes of front, middle and rear vehicle respectively increase by 3.53%, 3.45% and 2.01% on average, the vertical forces of the isolators 1 and 4 decrease by 13.3% on average, the vertical forces of the isolators 2 and 5 decrease by3.8%, and the vertical forces of the isolators 3 and 6 decrease by 20.9%. Thus it can be seen the comfort