Fault Clearing Time

[hle42000]

I have a new project on the technical review stage. Basically, this project has a single turbine generator is running a parallel with grid. But, the grid owner requested to clear a generator fault with 1/4 of cycle if there is a fault. If we could not do this, then the project is dead. So, does any body know any protective relay and generator circuit breaker out there that can achieve this requirement? The other solution is to get an inductive generator with 4160V, 1.7MW, but I could not find any manufacturer can make this kind of induction generator. Does any body know any manufacturer out there?
Thank you for your help!

 

[dpc]

Typical 4160 V circuit breaker clearing times are 3 to 5 cycles.

Anything faster than this will require something fairly exotic. A G&W CLip might be able to satisfy the grid's ridiculous requirement:

http://www.gwelec.com/pdfs/Clip/CLiP2010_web.pdf

Is is possible that someone is misinterpreting something? This is a very odd requirement.



David Castor

http://www.cvoes.com

 

[ScottyUK]

A decent relay might detect certain faults within a ¼ cycle but I've not heard of any breaker which can clear a fault that fast. I agree, a very strange 'requirement' and probably one which has arisen because of a misunderstanding somewhere.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[sibeen]

An Australian company makes a 'solid state' circuit breaker that may suit your needs. I'd be fairly sure that they wouldn't be the only manufacturer of such devices.

http://www.thycon.com.au/ssb_concept.shtml

 

[ScottyUK]

Interesting stuff, sibeen. Thank you.


----------------------------------

If we learn from our mistakes I'm getting a great education!

 

[sibeen]

I used to work for the company, a very long time ago. As far as I know the solid state circuit breaker uses IGCT as a very fast acting switch.

 

[7anoter4]

Such short fault clearing could be achieved only with ABB Is-current limiter [5-10 ms only] See:

http://www.dpi.nsw.gov.au/__data/assets/pdf_file/0010/318709/18---Volker-Schmidt.pdf

I think the modern Is limiter is not provided with fuse as the older models and you don't need to replace the fuse. We used such a breaker to protect a synchronous compensator of 60 MVAR and the only boredom was to replace the fuse after the short-circuit.

 

[hle42000]

Hi 7anoter4 (Electrical)

I haven't used this kind of application before. So, you are saying if I include an Is limiter as shown on slide 16 of 27 in the switchgear panel, then it will clear the fault within 5-10ms? This Is limiter will take the responsibility to clear the current fault by open itself to isolate the generator before the protective relay sends a signal to trip generator circuit breaker right? Would you please explain a little bit in more details since I am new with this application?
Thanks for your help again!

 

[7anoter4]

First of all see thread238-225904
Second, for your application will be better to contact ABB for more details.
See:

http://www.abb.com/product/db0003db004279/c125739900636470c125698c00553a43.aspx?tabKey=6