Research On Temperature-rise And Current Carrying Capacity Of OCS

As part of the electrified railway traction power supply system,the overhead contact system(OCS)is supposed to provide electricity to the train.Due to some economic and technical reasons,the contact line has no spare system.Thus,the structural stability and performance have direct influence on the absorbing current of the locomotive.Furthermore,the mechanical and electrical properties of OCS will be impacted by the temperature-rise of overhead contact lines.It is therefore quite necessary to make study on this issue.The temperature of overhead contact lines will rise in case electric current passing through the contact lines.This rise can also be caused by some environmental condition such as sun exposure,wind speed etc.Since the temperature-rise is an important factor that can limit the current carrying capacity and short-circuit current carrying capacity of OCS,thus it is necessary to study the relationship between the two indexes.This study can provide theoretical support to the design of OCS.It can also be used to test whether the equipment meets the technical requirements on temperature-rise and current carrying capacity.In the work of factors that impacting temperature-rise of contact lines and the influence of temperature-rise on OCS,the author found several major factors,i.e.,joule heat,solar radiant heat,thermal convection and thermal radiation.The parameters related to the heat calculation were selected.A heat balance equation was written according to the law of energy conservation.The relationship between temperature-rise and current carrying capacity was studied.The corresponding calculation method and formula were listed.The accuracy of the method was also verified.Through taking the AT power supply mode as an example,the author got the maximum allowable current carrying capacity of OCS with different types of lines under specified temperature at 95?.