Seismic calculations of directly buried gas-insulated transmission lines (GIL)

Gas Insulated transmission Line (GIL) is very well known for its high transmission rating of electrical power and its reliability. The high capacity of the transmission, the thermal, mechanical and the electrical behaviour of the new generation of the directly buried GIL were studied and tested by laying it in the ground in a long term test. To know the behaviour of the GIL in case of an earthquake, it is difficult to test a long length of the system by using a shaking table. So a seismic simulation with a help of finite element analysis with different accelerations has been done and confirmed that the line withstands the combination of the acceleration 0.5 g in both vertical and horizontal directions without any damage. The Von Mises stress is under the elastic limit by using an aluminium alloy for the conductor and for the enclosure.