Research On Pantograph System

High-speed railway is an inevitable trend of the railway modernization construction. And high-speed railway all adopts electric traction. The pantograph must obtain electric power dependably, which can influence the train running and performance of electric drive system. How to make the current collecting quality well is a key technique of high-speed electrical railway. The serious problem of pantograph-catenary system is obvious after the railway reconstruction for speed upgrading and the construction of high-speed dedicated passenger railway in China.From the aspects of changing the relationship of pantograph and catenary improving the current collecting performance, the following main aspects are discussed in thesis:Above all, the nonlinear perpendicular kinetic differential equation of pantograph is derived from a Lagrange Equation. The nonlinear model of pantograph is linearized and the calculation formulas are obtained. At the same time, the nonlinear model of pantograph is linearized to establish the function expression of the equivalent parameters, and each member bar parameters' influences exerting on the equivalent parameters was studied. Then Newton-Euler equation is obtained from Newton's theory by the analysis schematic of pantograph, and the equation is solved to get constraint force of pivot point.Next, the geometric relation model of high-speed pantograph frame structure is developed in this paper. Considering the detailed demands of locomotive's stable current collecting for pantograph mechanism, the objective function of the translation of pantograph-head balancing bar and the confining conditions of the demands which the pantograph mechanism must meet to work properly, are determined. The geometric parameters are calculated by using the single objective optimization technique and a series of parameters obtained optimized the pantograph performance. Also, the optimization result is analyzed thoroughly. Kinetic performance is improved by the use of optimization technique.Thirdly, in order to ensure better current-receiving quality between pantograph and catenary, The wide use of new alloy materials for high-speed pantograph can also cause the deficiency of the mechanical strength and stiffness. How to ensure sufficient mechanical strength and stiffness but small equivalent quality to improve the dynamic behavior of the pantograph catenary system is a serious problem of the pantograph design. In the design procedure of pantograph, the three-dimensional simulative model of the pantograph was set up to check the strength and rigidity, and study on dynamic property, by use of ANSYS. Research on dynamic property is to reach optimum design purpose of pantograph structure parameters and control its natural frequencies and modes, so it has a guidance meaning for the design of pantograph. The virtual design of the pantograph was done by use of the finite element analysis. And the whole structure characteristics of the high-speed pantograph are analyzed for the first time.And finally, in order to take account of the implementation of the elastic upper arm, the interface program FEMBS between finite element analysis codes and SIMPACK is used here to generate input data for flexible bodies for MBS simulation. By using ANSYS and SIMPACK (dynamics analysis software of the multibody system), rigid-flexible coupling analysis platform of the pantograph-catenary coupling system was established in the design procedure of high-speed pantograph. Natural frequencies of the rigid body change with arch stiffness in different operational height were researched, and comparison of rigid and rigid-flexible coupling mode at the same operational height was set up. The response of contact force and vibration of rigid and rigid-flexible coupling the pantograph-catenary system under different running speed was calculated. Rigid-flexible coupling model of the pantograph was set up for the first time based on multi-body dynamics, and useful results were obtained.