水电站生态调度操作门机动力学分析与安全性评价

Dynamic Analysis and Safety Evaluation of Ecological Dispatching Operation Gantry of Hydro-power Station

水电站生态调度操作门机受到耦合动力学、欠驱动、作业环境等因素的影响,其结构的振动和有效载荷的摆动会产生结构破坏并影响整机稳定性与作业精度.基于模态综合法和有限元法分别建立带轨道的门架结构降阶模型和绳索结构有限元柔性体模型,利用虚拟样机建模技术,搭建操作门机刚柔耦合动力学模型,分析了小车运行速度和加速度、起升重量、绳索摆长等参数对有效载荷摆动以及门架结构振动的影响.同时,选取结构性能指标和动力学性能指标,通过安全指标雷达图动态评价了操作门机的安全性.研究结果表明:小车运行速度和加速度对主梁水平位移的影响明显大于对垂直位移的影响;主梁的最大应力幅值与起升重量成正比;有效载荷的残余摆动和主梁的水平位移幅度范围正相关于绳索摆长的大小.操作门机动力学分析与安全性评价方法为这类门式起重机的使用与维护提供了参考.

The ecological dispatch operation gantry in hydro-power station is affected by the coupled dynamics,under-drive and operating environment.The vibration of its structure and the oscillation of payload will produce the structural damage and affect the stability and the operating accuracy of the whole machine.Based on the modal synthesis method and the finite element method,a reduced-order model of the gantry structure with the rail and a finite element flexible body model of the rope structure are established respectively.By using the virtual prototype modelling technology,a rigid-flexible coupled dynamics model of the operating gantry is built,and the effects of the parameters such as trolley running speed and acceleration,lifting weight and rope swing length on payload oscillation and gantry structure vibration are analysed.Meanwhile,the indicators of the structural and dynamic performance are selected and the safety of the operating door machine is dynamically evaluated by the means of radar diagrams of safety indicators.The results show that the influence of trolley running speed and acceleration on the horizontal displacement of the main beam is significantly greater than that on the vertical displacement.Furthermore,the maximum stress amplitude of the main beam is proportional to the lifting weight.The residual swing of the payload and the horizontal displacement amplitude range of the main beam are positively related to the size of the rope swing length.The methods for the analysis of the dynamics and the safety evaluation of operating gantry provide the reference to the use and maintenance of the gantry cranes.