The Optimization Of Pantograph Structure Parameters And The Research On Active Control Of Pantograph

Current collecting performance is urgent to be improved for high-speed railway and better relationship between pantograph and catenary is the key to this problem. So this requires improving dynamic performance of pantograph and catenary.From the aspects of changing the relationship of pantograph and catenary and improving the current collecting performance, two main topics are discussed in this thesis: firstly, from the locomotive's stable running and current collection's demands for pantograph, the geometric parameters of pantograph's frame structure are optimized; Secondly, to reduce the fluctuation of the contact force between the pantograph and catenary, active control of pantograph is studiedAbove all, 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.Next, the nonlinear perpendicular kinetic differential equation of pantograph is derived from a Lagarangian Equation. The nonlinear model of pantograph is linearized and the calculation formulas are obtained. At the same time, the finite element model of the catenary and the model of the coupling system of the pantograph/catenary are performed. Finally, based on the studies above, the characteristics of pantograph/catenary are analyzed and the active pantograph is modeled. By using the linear quadratic optimal control law, the design objective is to minimize the performance index, which is a function of the state variables representing the pantograph's dynamic characteristic and the active control force. The control system is designed considering the complete state feedback. To verify the control's effect, the simulation is performed and the result is analyzed. And then, the number of the state variable in the feedback is lowered through analyzing the function of the state variables to the control force, therefore, to realize the control law is much easier. At the same time, the results at different speed are compared, and the paper comes to a conclusion that the results at the higher speed is much more obvious. The design of the pantograph's active control system and the study of the simulation results reduce the fluctuation of the contact force theoretically and thus improve the current collecting quality.