Effect of Ambient Temperature on Current Collection Quality in Pantograph-Catenary Interaction

This paper investigates the effect of the ambient temperature change on the dynamic interaction between pantograph and catenary (PAC). Thermal expansion/contraction of the components of the overhead contact system (OCS) is considered. Simulation results show that the thermal stress has a much greater influence on the longitudinal positioning of the contact wire than on the horizontal and vertical positioning. When ambient temperature reduces to - 60 degrees from design temperature of 20 degrees C, the maximum longitudinal displacement of the positioner can reach as high as 301 mm, while the maximum horizontal and vertical displacement of the positioner is within 4mm. The change of ambient temperature results in the uneven tension distribution of the contact wire, especially near the central anchor. With the increase in temperature, the tension of contact wire decreases; vice versa, with the decrease in temperature, the tension of contact wire increases. For nine-span OCS, the tension change caused by ambient temperature change shall not exceed 2%. The variation of ambient temperature also leads to the deterioration of current collection quality. It is shown that a decreasing ambient temperature results in more significant changes in contact force, close to 5%. An increasing ambient temperature environment leads to a higher uplift of pantograph, close to 30%.