Research On Dynamic Characteristic Of Pantograph-catenary And Its Influence To Electromagnetic Noise

In order to study the dynamic characteristics of the pantograph-catenary,the finite element models of catenary and pantograph are established and the modeling method is introduced.Through the simulation analysis of the catenary model,the natural frequency,vibration mode and stiffness characteristics of the catenary are obtained.Based on the analysis of the structure of the high-speed pantograph SSS400+,the relationship between uplift torque and uplift angle or height and uplift angle was obtained.The overall stress,natural vibration frequency,vibration mode and frequency response characteristics of the pantograph are simulated and analyzed.The dynamic characteristics of the contact force of the pantograph-catenary under variable speed condition are studied.When the train was running on variable speed,on the top of the pantograph upper frame pipe,there will produce a vertical displacement by the elastic characteristics,which will affect the contact force changing.The vertical stiffness of the upper frame on the pantograph is obtained through the simulation analysis of the finite element model.What's more,the relationship between the acceleration of the train and the vertical dynamic inertia force is obtained.The coupling model of pantograph-catenary coupling is established,simulation results show that:when the train accelerates in the closed knee direction,the contact force decreases.When the speed is less than 250km/h,it increases the off-line probability.While in the open knee direction,the contact force becomes larger,and the instantaneous contact force will be too large at high speed,which exacerbates the wear and contact force fluctuation of the pantograph-catenary.While considering the vehicle vibration,there is a very small influence to the contact force.The active control method of pantograph air-spring is proposed to reduce the fluctuation amplitude of contact force and reduce the strength of electromagnetic noise.The working principle of the pneumatic loop with active control of the pantograph air-spring is introduced,and the mathematical model of the electro-pneumatic proportional valve and air-spring are established.The results show that the fuzzy active control model can reduce the fluctuation range of contact force in the response frequency range of the air-spring(v<380km/h).In order to study the influence of the contact condition to the electromagnetic noise,an electromagnetic noise experimental system is developed.The system is composed of anechoic chamber,pantograph electromagnetic noise testing machine,electromagnetic noise measurement and control system.The distribution law of radiation electromagnetic noise of the pantograph is studied through experiment,and the change relations with contact force,velocity and current are obtained.From the perspective of harmonic distortion,the changing regularities and characteristics of conductive electromagnetic noise with contact force,velocity and current are studied.a transmission electromagnetic noise regression model is established by using the SVM,which can provide a strong theoretical basis for the same work on pantograph-catenary system.