davva
Marine/Ocean
- Sep 27, 2004
- 99
I am working on a project based in China which has two medium voltage 10kV incomers to the plant via a star/delta 115/10.5kV utility transformers.
I am not responsible for the protection engineering on the 10kV system but I wondered what the optimum solution was for the plant in terms of detecting a single earth fault on the 10.5kV network.
From what I've read I was of the opinion that it would it be advisable to have neutral voltage displacement relay on each incomer switchboard to detect the presence of an earth fault. This could raise an alarm (or trip?), I guess you loose the benefit of an isolated neutral if you are tripping though? This would not pin point the location of the first fault or selectively isolated the affected area, so I guess you need some sort of fault location system then.
(Obviously the fault would have to be located before another phase fault occured on another phase).
In terms of locating the fault could sensitive earth fault relays be an option?
Is the above along the right lines or are there better solution(s)?
It is only to better my understanding in this area so any response is greatly appreciated.
Thanks in advance.
I am not responsible for the protection engineering on the 10kV system but I wondered what the optimum solution was for the plant in terms of detecting a single earth fault on the 10.5kV network.
From what I've read I was of the opinion that it would it be advisable to have neutral voltage displacement relay on each incomer switchboard to detect the presence of an earth fault. This could raise an alarm (or trip?), I guess you loose the benefit of an isolated neutral if you are tripping though? This would not pin point the location of the first fault or selectively isolated the affected area, so I guess you need some sort of fault location system then.
(Obviously the fault would have to be located before another phase fault occured on another phase).
In terms of locating the fault could sensitive earth fault relays be an option?
Is the above along the right lines or are there better solution(s)?
It is only to better my understanding in this area so any response is greatly appreciated.
Thanks in advance.