Study On Temperature Field Of Underground Power Cable Based On The Finite Element Method

Being a kind of important power equipment, the number of applied power cablehas increased rapidly in our country. Its laying mode has also changed from the verybeginning’s single loop soil buried to today’s cable channel buried, power tunnelburied, pipe buried and so on. And in the same one cable line, there often aremultichannel loop laying cable ways. The complex installation and layingenvironment makes it hard to increase the carrying capacity of power cables.The carrying capacity of power cables is composed of the temperature at whichthe insulation works. In the traditional calculation of carrying capacity method, theparameters were generally taken the recommended values of IEC-60287standard.This standard classify the soil around cable into two kinds--the local desiccation andnot. Effectively, the heat resistance coefficient of soil is very sensitive to soilmoisture content. And the classification method which divides soil into those twocases to study the carrying capacity is not correct.This paper used finite element method and analysis algorithm method tocalculate the loss of different regions in power cables. And for typical laying method,temperature field models are established. Then, the models are tested and verifiedthrough the results of simulation test. According to the theory of heat transfer, thispaper proposed the way by laying tap water pipe under the cables to reduce thehighest temperature of the field and promote the carrying capacity of power cables.Finally, the feasibility of this approach is validated by the simulation experiment.Domestic scholars have proposed that it could increase the carrying capacity ofcables and speed up the cable’s heat sink by filling medium between the cables andpipe. To the object of filling water in preset pipe, this paper got the theory carryingcapacity promotion effect when the temperature of flowing water is at differenttypical degrees.