UK Vintage Radio Repair and Restoration Powered By Google Custom Search Vintage Radio and TV Service Data

Go Back   UK Vintage Radio Repair and Restoration Discussion Forum > General Vintage Technology > Websites

Notices

Websites Found an interesting website? Post the details here and share it with the rest of us. Please stick to websites that are in some way related to our hobby/interest.

Closed Thread
 
Thread Tools
Old 1st Nov 2010, 7:31 pm   #1
Guest
Guest
 
Posts: n/a
Default National grid frequency

After the thread on the grid here is an interesting site http://www.dynamicdemand.co.uk/grid.htm
 
Old 1st Nov 2010, 7:50 pm   #2
Framer Dave
Rest in Peace
 
Join Date: Dec 2006
Location: Near Wrecsam, North Wales
Posts: 356
Default Re: National grid frequency

Very interesting! As is this:

http://www.nationalgrid.com/uk/Elect...Data/Realtime/

Regards,
Framer Dave is offline  
Old 1st Nov 2010, 10:06 pm   #3
murphyv310
Dekatron
 
murphyv310's Avatar
 
Join Date: Sep 2006
Location: Kilmarnock, Ayrshire, UK.
Posts: 5,420
Default Re: National grid frequency

There seems to be a problem with the national grid site, every page reports an error. Dynamic Demand over the last few minutes reports a frequency nearly at 50.2hz, all very odd!
__________________
Cheers,
Trevor.
MM0KJJ. RSGB, GQRP, WACRAL, K&LARC. Member
murphyv310 is offline  
Old 1st Nov 2010, 11:22 pm   #4
AlanBeckett
Rest in Peace
 
Join Date: Dec 2008
Location: Burton upon Trent, East Staffordshire, UK.
Posts: 1,686
Default Re: National grid frequency

It's all working OK for me - Fireox 3.6.12
Alan
AlanBeckett is offline  
Old 2nd Nov 2010, 1:54 pm   #5
HamishBoxer
Dekatron
 
HamishBoxer's Avatar
 
Join Date: Aug 2007
Location: W.Butterwick, near Doncaster UK.
Posts: 8,923
Default Re: National grid frequency

all ok here.

David
HamishBoxer is offline  
Old 2nd Nov 2010, 3:42 pm   #6
twocvbloke
Retired Dormant Member
 
Join Date: Oct 2010
Location: Colne, Lancashire, UK.
Posts: 527
Default Re: National grid frequency

I've been watching that frequency meter on and off for the past month, it's funny watching it go up and down in relation to TV programmes...

I wouldn't mind having a real one though, something I could plug in and watch without having to use internet bandwidth, just cos I'm sad like that...
twocvbloke is offline  
Old 2nd Nov 2010, 3:46 pm   #7
Andrew2
Nonode
 
Andrew2's Avatar
 
Join Date: Mar 2010
Location: Dukinfield, Cheshire, UK.
Posts: 2,034
Default Re: National grid frequency

Given that we have lots of generating sites all over the country, and that we swap power with France, how are all those 50Hz generators kept in phase?
__________________
Andy G1HBE.
Andrew2 is offline  
Old 2nd Nov 2010, 4:00 pm   #8
Martin G7MRV
Heptode
 
Join Date: May 2008
Location: Selby, North Yorkshire, UK.
Posts: 949
Default Re: National grid frequency

wow! do i not like that!? ive always known that specialists monitor the frequency to keep the grid balanced but never knew there was a website showing it!

Just watched it as a programme ended and there was indeed an increase in demand as the credits came up, but then it restored. Either the load planners are very good, or it was just a surge in people quickly channel hopping (didnt last long enough for kettle)
Martin G7MRV is offline  
Old 2nd Nov 2010, 4:06 pm   #9
Dave Moll
Dekatron
 
Dave Moll's Avatar
 
Join Date: Feb 2005
Location: West Cumbria (CA13), UK
Posts: 6,118
Default Re: National grid frequency

Quote:
Originally Posted by Andrew2 View Post
how are all those 50Hz generators kept in phase?
By being connected to the grid! Any generator attempting to slip out-of-phase finds itself being dragged back again by the very power lines to which it is connected.
__________________
Mending is better than Ending (cf Brave New World by Aldous Huxley)
Dave Moll is online now  
Old 2nd Nov 2010, 4:06 pm   #10
twocvbloke
Retired Dormant Member
 
Join Date: Oct 2010
Location: Colne, Lancashire, UK.
Posts: 527
Default Re: National grid frequency

Quote:
Originally Posted by Andrew2 View Post
Given that we have lots of generating sites all over the country, and that we swap power with France, how are all those 50Hz generators kept in phase?
It's all done by them people at the National Grid HQ at "Secret Location"...

Must be a fun job, sitting watching TV and then pressing a few buttons to adjust the supply...
twocvbloke is offline  
Old 2nd Nov 2010, 4:44 pm   #11
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: National grid frequency

If you want to watch the grid frequency, just get a frequency counter and connect it to the grid (e.g. a 12V secondary). You would need a counter which has a long gate time, so you can go down to 0.01Hz resolution. Or build a frequency multiplier or PLL so an ordinary RF counter can be used. Remember, the frequency is the same everywhere in the UK - except for those very rare occasions when the grid splits (and some Scottish islands?).

National Grid HQ is not that secret. It used to be in London near Bankside power station, and is now in Berkshire. They may do it differently now, but it used to be less important than the regional control centres. They try to predict 'TV pickups' etc. a day ahead so generation can be scheduled, and some power stations will be asked to regulate their output according to the mains frequency. If the frequency drops, they turn up the wick and generate a bit more power. At one time this would have been manual, but now computers do it.

The link with France is DC, so there are inverters/synchronous rectifiers at each end of the link. We are not synchonised with the Continent.
G8HQP Dave is offline  
Old 2nd Nov 2010, 5:29 pm   #12
russell_w_b
Dekatron
 
russell_w_b's Avatar
 
Join Date: Jul 2007
Location: Penrith, Cumbria, UK.
Posts: 3,684
Default Re: National grid frequency

Quote:
Originally Posted by twocvbloke View Post

It's all done by them people at the National Grid HQ at "Secret Location"...
I thought some of the emergency Grid HQs like the one at Rothwell Haigh, near Leeds were meant to be sort of secret; perhaps not...

Are the powers-that-be still obliged to maintain frequency to be correct over a 24Hr period like they used to? When Willowholme power station was on the go at Carlisle, we visiting apprentices were shown a large clock above the control board (I think it had two seconds-hands) so that electric clocks would maintain a mean accuracy over the course of the day, and the power-station controllers could adjust their output accordingly.
__________________
Regds,

Russell W. B.
G4YLI.
russell_w_b is offline  
Old 2nd Nov 2010, 5:56 pm   #13
ppppenguin
Retired Dormant Member
 
ppppenguin's Avatar
 
Join Date: Dec 2003
Location: North London, UK.
Posts: 6,168
Default Re: National grid frequency

Quote:
Originally Posted by G8HQP Dave View Post
You would need a counter which has a long gate time, so you can go down to 0.01Hz resolution.
Better to use a counter that has a reciprocal or period function. Then the input waveform is used as the gate. If the counter can do the reciprocal calculation then it will display 50Hz, otherwise you have to do it yourself.

AFAIK the grid still maintains the correct number of cycles in each 24 hour period. I have a friend who works in grid control so I'll ask him when I next see him. He says that the guys on the front line, the actual controllers, are very highly paid but under enormous stress.
ppppenguin is offline  
Old 2nd Nov 2010, 6:52 pm   #14
Tractorfan
Dekatron
 
Tractorfan's Avatar
 
Join Date: Mar 2008
Location: St. Frajou, l'Isle en Dodon, Haute Garonne, France.(Previously: Ellesmere Port, Cheshire, UK.)
Posts: 3,177
Default Re: National grid frequency

Hi
I think the link between France and the UK is DC so frequency changes on one side of "La Manche" won't affect t'other.
Cheers, Pete

Oops, I failed to spot the previous reference in post no.11, sorry.
__________________
"Hello?, Yes, I'm on the train, I might lose the signal soon as we're just going into a tunn..."

Last edited by Tractorfan; 2nd Nov 2010 at 7:02 pm.
Tractorfan is offline  
Old 2nd Nov 2010, 7:05 pm   #15
Guest
Guest
 
Posts: n/a
Default Re: National grid frequency

In the last hour I have got a large moving coil meter. Guess what for?
 
Old 2nd Nov 2010, 7:48 pm   #16
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: National grid frequency

Yes, I believe there are still supposed to be the right number of cycles in 24 hours, although I'm not sure what the accuracy has to be. There are limits on the permitted deviation from true 50Hz, and the accumulated error during the day.

I think the Leeds bunker was a bit more secret than others because it wasn't just for electricity. When I worked in the industry I got the impression that control centres were not secret but did like to keep a low profile, which is why I didn't say where in Berkshire the new HQ is. This sometimes backfired. The one in Manchester was in a housing estate and the locals believed rumours that it was a secret establishment for animal experiments, so the local oiks would throw stones and bottles over the wall and try to break the windows. Eventually they decided to invite the locals in and show them what really happened there. Better relations followed.
G8HQP Dave is offline  
Old 3rd Nov 2010, 12:30 am   #17
Top Cap
Octode
 
Top Cap's Avatar
 
Join Date: Mar 2006
Location: Watford, Hertfordshire, UK.
Posts: 1,270
Default Re: National grid frequency

Might be fun to get my HP5370B hooked up, it has a display of 12 digits which should enable me to monitor the 50Hz down to pico seconds. It will do an automatic measurement of mean deviation over 100,000 samples. The counter never gets used for much so the exercise may do it some good though I suspect it will take some time for the natural quartz oscillator to settle down.
__________________
Whether the Top Cap is Grid or Anode - touching it will give you a buzz either way!
Top Cap is offline  
Old 3rd Nov 2010, 1:03 am   #18
ALANS ANITAS
Rest in Peace
 
Join Date: Jun 2006
Location: North West Northamptonshire, UK.
Posts: 346
Default Re: National grid frequency

About 50 years ago, I was taken on a college outing to Battersea power station, and shown how an alternator was bought on line. This required the phase angle of the generator be compared to the National Grid frequency, and be reduced to zero, before being placed "on line." We were told serious mechanical damage would result from not complying with this procedure.

When umpteem million kettles are switched on, as "East Enders" finishes, quick start generators, such as pump storage and gas turbine stations are bought on line, so that voltage and frequency can be maintained.

ALAN
ALANS ANITAS is offline  
Old 3rd Nov 2010, 1:23 pm   #19
G8HQP Dave
Rest in Peace
 
Join Date: Sep 2008
Location: Solihull, West Midlands, UK.
Posts: 4,872
Default Re: National grid frequency

I have heard that you can get quite a loud bang if synchronising a bit late or early of the right spot - the grid gives the generator a good kicking!

The older gas turbine stations used for peak lopping are used as little as possible, as they are very expensive to run (they use jet fuel!). The new combined cycle gas turbines are much cheaper and used as base load sets, but can be less flexible than all the old coal-fired plant which is about to retire. One approaching problem is that much of the new generation coming on stream is either inflexible (CCGT, nuclear) or randomly variable (wind, solar). This makes frequency control rather difficult. I read recently that Germany has so much solar etc. that the variation might cause grid trips. We actually need a new generation of coal sets, but that now seems politically impossible.
G8HQP Dave is offline  
Old 3rd Nov 2010, 2:39 pm   #20
Jeremy M0RVB
Hexode
 
Join Date: Jul 2003
Location: Leeds, West Yorkshire, UK.
Posts: 455
Default Re: National grid frequency

[QUOTE=russell_w_b;376005]
Quote:
Originally Posted by twocvbloke View Post
I thought some of the emergency Grid HQs like the one at Rothwell Haigh, near Leeds were meant to be sort of secret; perhaps not...
Maybe once - but here's a pic http://www.subbrit.org.uk/rsg/sites/...rid/index.html
Jeremy M0RVB is offline  
Closed Thread

Thread Tools



All times are GMT +1. The time now is 4:34 pm.


All information and advice on this forum is subject to the WARNING AND DISCLAIMER located at https://www.vintage-radio.net/rules.html.
Failure to heed this warning may result in death or serious injury to yourself and/or others.


Powered by vBulletin®
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Copyright ©2002 - 2023, Paul Stenning.