Rough Surface Contact Model And Temperature Characteristics Simulation Of Sliding Electrical Contact

The temperature of the contact surface of the friction pair in the pantograph catenary system affects the wear and contact state,and then affects the life of the friction pair and the safety of the train operation.In order to study the micro and temperature characteristics of the contact surface,the sliding electrical contact experiment was carried out,and the rough surface contact model and temperature field simulation model of the sliding electrical contact were established.The experiments were carried out under different contact conditions.The voltage and current,contact pressure,contact surface micro parameters and contact surface temperature were collected,and the arc power,fractal dimension and fractal roughness under different conditions were calculated.The rough surface contact model of sliding electric contact is established to study the effect of roughness on the temperature change of contact surface.The simulation model of temperature field is established to study the influence of arc heat on the temperature of friction pair.The results show that under the same working condition,when the total energy of the arc is the same,the temperature rise of the contact surface under the action of a single arc is higher than that under the action of multiple arcs.The temperature rise of the contact surface will be reduced if the arc is dispersed and generated on the edge side of the contact line,so as to reduce the wear of the friction pair.When the arc acts at different times,the maximum temperature of the contact wire mainly depends on the arc close to the inner side of the contact wire and the distance between the acting positions.Compared with rainless conditions,the arcing time of pantograph catenary arc is shorter,the number of arcing is more,and the temperature rise will be higher.The influence of hardness on the contact surface is more significant under the condition of low current.When the microhardness of the contact surface is low,different contact current and sliding speed have great influence on the temperature of the contact surface,but the influence decreases when the microhardness is high.When the fractal roughness G does not change and the fractal dimension increases,the temperature of the contact surface decreases.When the fractal dimension D is not changed and the fractal roughness is increased,the temperature of the contact surface increases.Therefore,whether the fractal dimension or the fractal roughness changes,the temperature of the contact surface will be affected.The above conclusions can be used for reference in the further study of reducing the temperature rise of friction pairs.