Study On Sliding Contact Resistance Of Pantograph-catenary Under Fluctuating Load

In order to reveal the sliding contact resistance characteristics of the pantograph system under fluctuating loads,the existing sliding electric contact tester was improved.The dynamic pressure control module was added to achieve precise control of the fluctuating pressure load.At the same time,the monitoring interface and data processing system based on LabVIEW was designed.The immersed metal carbon sliding plate and the pure copper wire were used as the friction pairs to carry out current-carrying sliding electric contact experiments under kinds of experimental conditions including different pressure load amplitude and wave frequency,sliding velocity,and contact current.The change law of the contact resistance and how dynamic contact resistance mechanism affected by above factors was obtained and analyzed.The main experimental conclusions are that when the fluctuating load is 70±20N,the contact resistance appears a minimum point,and when the load fluctuation increases,the contact resistance gradually increases;the impact of the change of the fluctuation frequency on the contact resistance is not monotonous,but there is irregular random change;the contact resistance decreases with the increase of the current,and the contact resistance decline process becomes slow due to the increase of the temperature;the increase of the sliding speed causes the arc to intensify,resulting in the continuous increase of the contact resistance.At the same time,the surface morphology of the skateboard before and after the experiment was observed with a metallographic microscope,and the wear mechanism was analyzed.In this paper,using the particle swarm optimization algorithm to optimize the generalized regression neural network and combine the experimental results to obtain the contact resistance dynamic model.Using the experimental data to test the generalization ability of the model and verify its validity.Compared with the general GRNN model,we can clearly see that the superiority of PSO-GRNN.This paper provides a new method for further study on the sliding contact resistance of the pantograph under fluctuating loads.