Power0020
Electrical
- Jun 11, 2014
- 303
A 66 /11 kV Transformer connected to a 66 kV GIS with an overhead conductor portion and Surge arrestors just before the transformer bushings, the 11 kV bushings don't have surge arrestors and no surge arrestors are provided in the MV SWGR (about 90 m away), I suggest to do a overhead conductor jumper to cable termination frame and from that to MV SWGR via U/G Cables.
Another senior engineer suggested to terminate the cables directly to the bushing terminals to avoid overhead conductors and thus being subjected to lightning strikes during shielding failure, I wonder if this very short distance of overhead conductor just to bypass the Transformer tank (about 3 m) would required a surge arrestor (Similar to 66 kV side).
Another point here I usually like not to terminate cable directly to bushings to avoid transformer fire in case of termination failure as well as to avoid the propagation of bushing terminal heat towards the cable insulation.
Any clue?
Another senior engineer suggested to terminate the cables directly to the bushing terminals to avoid overhead conductors and thus being subjected to lightning strikes during shielding failure, I wonder if this very short distance of overhead conductor just to bypass the Transformer tank (about 3 m) would required a surge arrestor (Similar to 66 kV side).
Another point here I usually like not to terminate cable directly to bushings to avoid transformer fire in case of termination failure as well as to avoid the propagation of bushing terminal heat towards the cable insulation.
Any clue?