The DC traction power supply system has low voltage and heavy load. Due to the point contact during train operation, the resistance will increase the temperature rise and reduce the mechanical properties of the contact wires. Aiming at this problem, this paper establishes the electric contact model of the arch network of a typical railway, and obtains the law of the influence of running speed, train state and external environment on the electric contact temperature rise of the arch network. The results show that the contact temperature of the arch network decreases with the increase of running speed, and the contact temperature of the arch network under braking conditions is relatively high, with the highest contact temperature of 332K, about 59 ℃. The temperature of the contact line in the tunnel is higher than that in the open air environment, and compared with the current temperature rise standard of catenary, the configuration scheme of carbon slide plate for pantograph is proposed. The contact temperature rise of the arch net in the open air and tunnel environment is less than 80℃, which is within the standard range. Contact line wear has little effect on the contact temperature of the bow mesh. When the two-bow four-carbon skateboard is used, the maximum temperature rise of the bow net is 370K, which is close to the critical temperature tolerance value. When the single-bow two-carbon skateboard is used, the temperature rise is 440K, which exceeds the temperature rise allowed by the contact line and affects the performance. The operation of the single-bow two-carbon skateboard is not recommended. The research provides theoretical basis and data support for the selection of DC pantograph and system coordination.