Study On Temperature Field Of Catenary During Online Anti-icing

The icing of catenary seriously affects the safe and stable operation of electrified railway in china.The online anti-icing technology,which can not only achieve the effect of anti-icing,but also ensure that the traction network voltage meets the requirements of normal operation,is an ideal solution to solve the problem of icing in catenary.In this paper,the temperature field distribution of catenary in the process of online anti-icing was studied,which provides theoretical support for the further research and popularization of the online anti-icing technology.Firstly,the thermal balance equation of contact wire was established based on the heat exchange of contact wire surface in the process of online anti-icing,and then the formula for critical anti-icing current of catenary was obtained,the influences of wind speed and ambient temperature on the critical current of catenary and the contact wires made by different materials were studied.The contact wire current-carrying capacity obtained by cacultion based on the formula for critical anti-icing current of catenary was compared with that given by GB railway standards,which verifies the feasibility of using heat balance equation to calculate the critical anti icing current of catenary.Secondly,the horizontal temperature field of catenary during the online anti-icing was studied based on the finite element models of the whole dropper and the electrically connecting clamp which were established in ANSYS Workbench.The steady-state thermodynamic simulation analysis of the whole dropper and the electrically connecting clamp with different service life were performed.The fluid dynamic analyses of them were carried out by using the CFX module,the fluid-thermal coupling analyses were carried out by extracting the surface wind speed field,then the distributions of temperature field of catenary constituents were analyzed.The results show that the temperature field distribution of the whole dropper can meet the need of anti-icing,and the two results are very close,which verifies the correctness of the simulation results.Lastly,the longitudinal temperature field of catenary during the online anti-icing was studied.According to the limitation of network voltage and anti-icing effect,the on-line anti-icing currents of catenary under the direct power supply and AT power supply mode were determined,and then the currents along the catenary were obtained.The processes of the locomotive passing through the power supply section were introduced,and the temperature calculation formula of each process was obtained according to the change of the currents along the line.The influences of the reference point position and the locomotive speed on the longitudinal temperature field of the direct power supply catenary were analyzed by the set data,and the anti-icing effect of catenary under the direct power supply was verified by the measured data.The distribution of longitudinal temperature field of the points along the line was studied in the two cases where the anti-icing current can ensure the normal operation of the catenary terminal voltage and can’t ensure,and the effectiveness of the online anti-icing technology for AT power supply catenary was verified.