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#146112 10/20/06 08:49 AM
Joined: Apr 2006
Posts: 233
K
Kenbo Offline OP
Member
Looking for stuff about the grid for my students when I came accross this site.

Watching the grid

Silly to sit and watch a needle move but it what it represents I thought facinating [Linked Image]


der Großvater
#146113 10/20/06 11:57 AM
Joined: Jul 2002
Posts: 8,443
Likes: 3
Member
Kenny,
That's pretty cool!. [Linked Image]
I've seen the effects of the wrong frequency on a power system first-hand.
Our NZ (SI) members may remember back in 1992, when there was a problem at one of the Tekapo (I think) power stations and one of the alternators began what's known as "hunting" (speeding up and slowing down wildly).
Reason I say South Island only is because any power sent to the north is rectified into DC first.
This hunting effect caused a really eerie pulsing of the lights in peoples houses and caused quite a few problems with TV's and the like.
The pulsing was quite noticeable and so I'm told, Power companies recieved thousands of calls from concerned consumers.
Just goes to show what can happen when you have one errant alternator in a system.
And so I've learned since, it takes quite a bit of effort to get the alternator settled back into a steady speed again too.
Would have been interesting being a fly on the wall in the control room that night!. [Linked Image]

#146114 10/20/06 05:04 PM
Joined: Sep 2005
Posts: 97
J
Member
I like watching this link http://www.nationalgrid.com/uk/Electricity/Data/Realtime/Demand/Demand60.htm
It shows the UK demand in real time. It jumps up at 1 am when our economy 7 supplies kick in.


I took my time, I hurried up, The choice was mine, I didn't think enough
#146115 10/21/06 04:58 AM
Joined: Dec 2005
Posts: 869
Likes: 4
R
Member
Very interesting guys, thanks for giving those links.
Raymond


The product of rotation, excitation and flux produces electricty.
#146116 10/22/06 07:09 AM
Joined: Dec 2002
Posts: 1,253
D
djk Offline
Member
http://www.eirgrid.ie/EirgridPortal...;TreeLinkModID=1451&TreeLinkItemID=7

This isn't quite as flashy as a needle indicator, but it brings up list of various demand / supply tables etc for any given day in Ireland.

Gives you an idea of rate of increase in consumption : Weekly peaks for a few years.
http://www.eirgrid.ie/EirgridPortal...TreeLinkModID=1451&TreeLinkItemID=11



[This message has been edited by djk (edited 10-22-2006).]

#146117 10/22/06 06:33 PM
Joined: Mar 2005
Posts: 1,803
Member
Ken, I managed to stop looking at that stupid meter long enough to read on a bit. Seems they are looking at devices [for refrigerators etc.] that turn off when the hz is down and on again when it's up, and hope to eventually have these on lots of consumer products.
I imagined some wild future where every appliance sold has this switch, with everything electrical in the UK going on and off like a harlot's drawers, and the Poco desperately trying to keep the grid balanced! ROFL [Linked Image]

Alan [ formerly known as Doris ]


Wood work but can't!
#146118 10/23/06 03:26 AM
Joined: Apr 2006
Posts: 233
K
Kenbo Offline OP
Member
Alan [ formerly known as Doris ]

I think the idea is mainly for industrial users who recive large electric bill when they cause an imbalance on the load factor. If I remember rightly reigerators as capacitor start motors. But most mottors will make the phase lagg when running.

djk

I like the historical data on that site. Compare 25-12-2005 with a normal week day intresting

johno12345

Cool liked that site also


der Großvater

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