Foudrette
Electrical
- Sep 11, 2003
- 23
Dear All,
I work in the area of underground HV cable links design.
For underground cable ampacity calculation, it is necessary to take into account the thermal behaviour of the soil (this is one of the major parameters). IEC 60287 standard is commonly used to calculate cable ampacities. This standard is suitable for most of the ways of laying. But when you have to cross a road,a railway or a river the burial depth can reach important values (40 feet or 75 feet) for example.
If ampacity calculations are made according IEC 60287, results obtained are very pessimistic because it is assumed there is no change in soil thermal resistivity what is surely false. This leads to choose cable with very big cross-section (to reduce heat due to Joule's losses) what of course dramatically increases the cost of the cable and thus that of the cable link.
Maybe some of you have already studied these problems of soil thermal characteristics simulation. So I am very interested in any report, datas, graphs or contact in this area.
Thanks for all of your help,
Marie-Hélène
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I work in the area of underground HV cable links design.
For underground cable ampacity calculation, it is necessary to take into account the thermal behaviour of the soil (this is one of the major parameters). IEC 60287 standard is commonly used to calculate cable ampacities. This standard is suitable for most of the ways of laying. But when you have to cross a road,a railway or a river the burial depth can reach important values (40 feet or 75 feet) for example.
If ampacity calculations are made according IEC 60287, results obtained are very pessimistic because it is assumed there is no change in soil thermal resistivity what is surely false. This leads to choose cable with very big cross-section (to reduce heat due to Joule's losses) what of course dramatically increases the cost of the cable and thus that of the cable link.
Maybe some of you have already studied these problems of soil thermal characteristics simulation. So I am very interested in any report, datas, graphs or contact in this area.
Thanks for all of your help,
Marie-Hélène
