arc quenching&ups synchronisation
arc quenching&ups synchronisation
(OP)
hello, i have two question:
1-How a sf6 circuit breaker can catch the zero current to extinguish an arc ? is there a sensing device or this is a natural consequence of a mechanism designed?
2- is there any application such as parallel operation of ups with utility? i just ask due to curiosity , a think-tank perhaps, is it possible that a ups will take an a.c wave and after ac-dc-ac conversion its output will be the same with the original wave and both of them will supply a load and when the utility is gone ups will take over all the load without interruption? if there is no such an application is it possible ? might it be any obstacle that ups and utility have largely different internal impedances concerning the load sharing ?
1-How a sf6 circuit breaker can catch the zero current to extinguish an arc ? is there a sensing device or this is a natural consequence of a mechanism designed?
2- is there any application such as parallel operation of ups with utility? i just ask due to curiosity , a think-tank perhaps, is it possible that a ups will take an a.c wave and after ac-dc-ac conversion its output will be the same with the original wave and both of them will supply a load and when the utility is gone ups will take over all the load without interruption? if there is no such an application is it possible ? might it be any obstacle that ups and utility have largely different internal impedances concerning the load sharing ?






RE: arc quenching&ups synchronisation
That said, it is not advisible or desirable to run in parallel with the utility, and I doubt any UPS manufacturer would allow it. The reason you have a UPS is that you want to isolate your loads from any problems on the utility. If the utility experiences glitch while you're in parallel, the glitch can affect your load before you can isolate. If your load is strictly on the inverter, it will never see the glitch.
Finally, you have no reason to operate in a parallel-to-utility state. If your UPS can carry your critical load, there is no reason to parallel to the utility. If the UPS is not big enough for your load, a loss of utility would overload the UPS.
RE: arc quenching&ups synchronisation
The sole purpose of most UPS systems is to provide power to critical loads that will not tolerate any form of power interruption (brown outs, sags, total loss of utility etc).
There is no advantage whatsoever of running an inverter in parallel with the utility. As the inverter is a synthetic electronically generated sine wave there will always be points in time where the inverter will be slightly out of phase with the utility causing large unwanted circulating current. This will either damage the UPS or take out upstream breakers.
UPS engineer http://www.calibrepower.co.uk
RE: arc quenching&ups synchronisation
In most situations a UPS has AC-DC-AC conversion as you have stated. It also synchronises its output to the utility supply which is usually called the reserve or bypass supply.
In normal operation the load output is fed from the UPS via the inverter with battery back up to protect the load from any interruption. This inverter supply is always in synch with the bypass supply (utility). If the inverter fails within the UPS then a static switch will transfer the load to the bypass supply without any interruption.
Hope this helps.
UPS engineer http://www.calibrepower.co.uk
RE: arc quenching&ups synchronisation
RE: arc quenching&ups synchronisation
RE: arc quenching&ups synchronisation
RE: arc quenching&ups synchronisation
1 - there are switching control devices also known as Controlled point-on-wave switching devices used for independent pole operated CB.
Please find below some details for ABB SCS
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