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Posted By: ANNEMARIE power factor correction - 07/13/13 08:32 PM
Hi all can anyone tell me if the uk electrical networks have power factor correction capacitors fitted at 33/11kv substation sites or are these only fitted at supergrid sites thanks in advance annemarie
Posted By: boora2 Re: power factor correction - 07/25/13 11:41 AM
As I'm from Australia,a UK guy would be the best to answer this,but I seem to remember there is some gear at the 275kV Willsden yard to regulate the kVARS on the incoming cables to insure either one is not too badly overloaded at peak use times.
Posted By: Scott35 Re: power factor correction - 07/27/13 07:11 AM
If the UK's Utility Providers have protocols similar to the Utility Providers here in USA
(more precisely, the "EUSERC-Related" Utilities of the Western / Pacific States),
there will be KVAR Correcting Capacitor Banks at the Distribution Yards, and at specific locations on the Distribution Feeder Circuits.

Primary Distribution Feeders are nominally 12,470Y/7200V 3PH. 4W, with some 24,000V and 34,500V Systems.
Older installs were 4160Y/2400 3PH. 4W, however these Systems are being Phased out where possible.

All Polyphase Transformer Primary connections are L-L Delta (12KV). Primary Side connections for Single Phase Pole-Mounted Transformers typically are connected L-L (12KV), but in LADWP Territory, the majority of 1 PH. Pole Mounts are L-N (2400V or 7200V).
In my area, the only L-N Single Phase Primary Terminations are for Pad-Mount Transformers.

KVAR Correction at Distribution Yards is placed on the 12KV Primary Distribution Feeders' side.
(BTW, in my area, the Sub-Transmission Circuit Voltage is 66KV, and the "Main" Transmission Circuit Voltage is 138KV)

The Yards have some PF Correction Banks constantly connected, and others connected per Time-Of-Use (TOU), via Cut-Outs.

For the remote locations (Pole Mounted Banks), there are some Permanently-Connected Banks, and some Banks which are connected via 15KV Oil-Immersed Cutout Switches.
A Time Clock, or Remote Controller opens and closes these Switches.
At each of these types of Correction Banks, there is a small (5 KVA maximum) 12KV to 120/240V Transformer, which supplies Power for the Control Equipment.

I am also interested in the UK's Primary Distribution PF Correction methods.
When you find the information, please reply!

--Scott (EE)
Posted By: ANNEMARIE Re: power factor correction - 07/27/13 08:25 PM
Hi thanks for the replys I think the us system is a bit different from the uk because we dont have so many xformers we tend to have 1 tranny per 150 houses im hoping that someone from a uk based poco will reply sometime soon My local supply company wont tell me anything wich is why i asked here thanks annemarie
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