Europe has just had a week of unseasonably cold weather (I clocked -8C air temp in March!), so no great surprise that loads were on the high side, I am not at all surprised the frequency drooped a little.
What is surprising is just how high the frequency is being allowed to go to correct, the uk
http://www.gridwatch.templar.co.uk/ is showing 50.1Hz on 49GW of demand.
Regards, Dan.
So anyone that noticed their clock running behind will have corrected that by now, and will have to do this again soon when the correction in the net frequency has been done
It must have been really slow for a while then.
Thursday was bad. See attach. Source:
http://map.pqube.com/ (no you do not access the loggers live, they are barely capable of serving one user)Edit: as is the
next day, averaging 49.985 Hz.
I never realized the frequency changed based on load until I saw a video about everyone starting up their kettles at the same time causing them to have to fire up extra capacity. I guess it makes sense, since most power plants are based on generating AC from spinning turbines so any extra physical resistance is going to make it harder to turn, so it will turn slightly slower. All power plants will more or less sync due to magnetics. Each one would need to start pushing a little harder more or less in sequence to speed them up again.
That data logging is neat, would be kinda neat to set something like that up at home for fun.
I never realized the frequency changed based on load until I saw a video about everyone starting up their kettles at the same time causing them to have to fire up extra capacity. I guess it makes sense, since most power plants are based on generating AC from spinning turbines so any extra physical resistance is going to make it harder to turn, so it will turn slightly slower. All power plants will more or less sync due to magnetics. Each one would need to start pushing a little harder more or less in sequence to speed them up again.
That data logging is neat, would be kinda neat to set something like that up at home for fun.
Simpler than logging, if you want to see it in real time, get a 2 channel scope, get a crystal locked 50/60hz signal on 1 trace, and, probe the mains through a cheap ac transformer on the second channel. Watch you mains slowly scroll in one direction, then slow down, then scroll in the other direction, every few minutes. Well, it's like that for Hydro Quebec here in Montreal. The average over a few hours is corrected to be 60hz exactly, but, every few minutes, it drifts above and below 60hz visible on my scope with the above setup.
I believe in North America, recently, our 60hz grids, if the power is sold across province/state borders, our 60hz needs to be tuned to a GPS referenced clock, so it has been said on a PBS documentary about our power grid. I'm not sure how recent or accurate this info may be.
That data logging is neat, would be kinda neat to set something like that up at home for fun.
The price is a bit prohibitive. But there are a few of those units on Ebay in the US.
Europe has just had a week of unseasonably cold weather (I clocked -8C air temp in March!), so no great surprise that loads were on the high side, I am not at all surprised the frequency drooped a little.
What is surprising is just how high the frequency is being allowed to go to correct, the uk http://www.gridwatch.templar.co.uk/ is showing 50.1Hz on 49GW of demand.
Regards, Dan.
I take it you're in the UK too? Over the weekend and start of this week, temperatures have recovered here but perhaps they're still below normal on the continent?
According to the news the low frequency has been caused by some electric producers in the Balkan.
It has also revealed a flaw in the Dutch air raid siren system. During the monthly test quite a few stayed silent because the clocks wheren't synchronised. Really?
What is surprising is just how high the frequency is being allowed to go to correct, the uk http://www.gridwatch.templar.co.uk/ is showing 50.1Hz on 49GW of demand.
That's totally irrelevant to the central European grid frequency as the UK National Grid only has HVDC interconnects to continental Europe and Ireland so the grid frequency in Great Britain is independent. The only long distance AC interconnect is to the Isle of Man.
What is surprising is just how high the frequency is being allowed to go to correct, the uk http://www.gridwatch.templar.co.uk/ is showing 50.1Hz on 49GW of demand.
That's totally irrelevant to the central European grid frequency as the UK National Grid only has HVDC interconnects to continental Europe and Ireland so the grid frequency in Great Britain is independent. The only long distance AC interconnect is to the Isle of Man.
Your grid is now 50.127 Hz, that's way worse that what we are having!
Anyone else experience lagging text and slow responses on the post reply page?
I never realized the frequency changed based on load until I saw a video about everyone starting up their kettles at the same time causing them to have to fire up extra capacity. I guess it makes sense, since most power plants are based on generating AC from spinning turbines so any extra physical resistance is going to make it harder to turn, so it will turn slightly slower. All power plants will more or less sync due to magnetics. Each one would need to start pushing a little harder more or less in sequence to speed them up again.
That data logging is neat, would be kinda neat to set something like that up at home for fun.
Simpler than logging, if you want to see it in real time, get a 2 channel scope, get a crystal locked 50/60hz signal on 1 trace, and, probe the mains through a cheap ac transformer on the second channel. Watch you mains slowly scroll in one direction, then slow down, then scroll in the other direction, every few minutes. Well, it's like that for Hydro Quebec here in Montreal. The average over a few hours is corrected to be 60hz exactly, but, every few minutes, it drifts above and below 60hz visible on my scope with the above setup.
I believe in North America, recently, our 60hz grids, if the power is sold across province/state borders, our 60hz needs to be tuned to a GPS referenced clock, so it has been said on a PBS documentary about our power grid. I'm not sure how recent or accurate this info may be.
That's an interesting way to visualize it. I've plugged into mains before and just read the frequency number but having both waves would let you visualize it more.
Actually, does the wave form lag a bit between very long distances? I imagine that makes interconnections quite complex. Ex: the wave might be at the peak in one region but in another it might not be quite there yet.
Actually, does the wave form lag a bit between very long distances? I imagine that makes interconnections quite complex. Ex: the wave might be at the peak in one region but in another it might not be quite there yet.
Yes, there are transmission line effects. Which makes it quite complicated, because after sync you first have to counteract the capacitance of the cable before actual power is going trough.
It's even essential all three phases are exactly the same length.
What is surprising is just how high the frequency is being allowed to go to correct, the uk http://www.gridwatch.templar.co.uk/ is showing 50.1Hz on 49GW of demand.
UK statute is 50Hz+-0.5Hz. Outside that and explantions have to be made.
Those responsible for balancing generation and demand are more worried about having too much generation than too much demand. It is easier to shed load than it is to shed generation. Above 52Hz transmission gear would start to be damaged.
It is entirely possible for there to be a 1GW reduction in demand within 0.5s. Ouch. That has been seen when one of the two UK-France links "popped out".
https://www.platts.com/latest-news/electric-power/london/kosovo-serbia-imbalance-impacting-european-system-26903978System frequency deviation caused by political disagreement between Kosovo and Serbia is affecting the whole of continental Europe's power system and must stop immediately, transmission system association Entso-e said Tuesday.
Kosovo has been using more power than it produces while Serbia, responsible for balancing the Kosovo grid, has failed to do this, Nies said.
As a result, Serbia has been free-riding on the system.
Political disagreements between the Serbian and Kosovar authorities "have led to the observed electricity impact. If no solution can be found at political level, a deviation risk could remain," Entso-e said.
The average frequency since mid-January has been 49.996 Hertz, resulting in 113 GWh of missing energy.
It has also revealed a flaw in the Dutch air raid siren system. During the monthly test quite a few stayed silent because the clocks wheren't synchronised. Really?
Huh? So a system designed to work when all else fails is derailed this easily. Good thing that these sirens are soon going to be replaced by NL-Alert. A system that only works when my phone settings are OK, it is in reach of a cell tower, switched on, charged and within hearing distance. I feel so much safer now
I certainly hope the nuclear plant 7 miles away does not decide to blow its stack in my lifetime.
Back in the 60s, when working with broadcast video VTRs, we monitored the mains frequency because we had to manually adjust the VTRs to re-synchronise them if the mains frequency shifted too far off. It was a regular occurrence in those days that a very popular show used to finish just before the Nine o'clock news. On many occasions during the 10 second run time lead in for the News headlines the mains frequency used to drop by 0.1 Hz. This used to cause real problems trying to keep the VTR in synch with a moving target. The reason 'thousands of kettle being switched on across the UK' putting a sudden very high load on the National Grid.
Back in the 60s, when working with broadcast video VTRs, we monitored the mains frequency because we had to manually adjust the VTRs to re-synchronise them if the mains frequency shifted too far off. It was a regular occurrence in those days that a very popular show used to finish just before the Nine o'clock news. On many occasions during the 10 second run time lead in for the News headlines the mains frequency used to drop by 0.1 Hz. This used to cause real problems trying to keep the VTR in synch with a moving target. The reason 'thousands of kettle being switched on across the UK' putting a sudden very high load on the National Grid.
Indeed, and I may still have a paper graph somewhere of the demand surge after (IIRC) Miss World finished.
Such things were the reason for building the world's largest man-made cave, in Dinorwig
I never realized the frequency changed based on load until I saw a video about everyone starting up their kettles at the same time causing them to have to fire up extra capacity. I guess it makes sense, since most power plants are based on generating AC from spinning turbines so any extra physical resistance is going to make it harder to turn, so it will turn slightly slower. All power plants will more or less sync due to magnetics. Each one would need to start pushing a little harder more or less in sequence to speed them up again.
That data logging is neat, would be kinda neat to set something like that up at home for fun.
Simpler than logging, if you want to see it in real time, get a 2 channel scope, get a crystal locked 50/60hz signal on 1 trace, and, probe the mains through a cheap ac transformer on the second channel. Watch you mains slowly scroll in one direction, then slow down, then scroll in the other direction, every few minutes. Well, it's like that for Hydro Quebec here in Montreal. The average over a few hours is corrected to be 60hz exactly, but, every few minutes, it drifts above and below 60hz visible on my scope with the above setup.
I believe in North America, recently, our 60hz grids, if the power is sold across province/state borders, our 60hz needs to be tuned to a GPS referenced clock, so it has been said on a PBS documentary about our power grid. I'm not sure how recent or accurate this info may be.
That's an interesting way to visualize it. I've plugged into mains before and just read the frequency number but having both waves would let you visualize it more.
Actually, does the wave form lag a bit between very long distances? I imagine that makes interconnections quite complex. Ex: the wave might be at the peak in one region but in another it might not be quite there yet.
Yup, just zoom in to see around 1/2 to 1 sine wave on your scope, while you are locked onto a clean 60hz square wave from your function generator. You will see the mains 60hz sine scroll on by fairly fast at times, like right across the display within a fast as a few seconds. It will, in my case, it slows down/reverse/speeds up either which way depending on the total load on our hydro power station and how they regulate the velocity of the generators.
Slow clocks are the least of Kosovo's problems. Kosovo has 60% unemployment, corruption by the mafia style government is rife, has Serbs as neighbours, and has no hope for young people because they have nowhere to go (Kosovo is not a member of the EU). The place is very poor and is literally falling apart. Kosovo is a basket case.
I have experienced a very slow clock here in Australia. I bought a telephone answering machine in the USA in 1993 and brought it back to Australia. It used the mains frequency for its clock, so it ran slow hare... 50 minutes ticked over every 60 minutes. Damn. I opened it up, reverse engineered the circuit, removed the mains input to the RTC chip and used a very nice 8 pin IC that used the 50 Hz mains as a phase locked loop for a 60 Hz oscillator. The IC was bought at Dick Smith Electronics before it became a toy store. The circuit worked a treat.
Years ago we developed a long range PLC based communication system for utilities. All of our testing in USA/Mexico/Canada was going very well and then we setup a test site on a Caribbean island and we started seeing data drop outs. After a bit of remote troubleshooting we realized the frequency was going up and down like a yo-yo string. After we widened our nominal frequency range (software tweak) the data loss dropped right off (at least while the power was on). During one of our visits the engineer from the local utility pointed out that the cruise ship in the port that morning had more generation on board than the entire island, so you need to expect the frequency to bounce around a bit.
If I recall NERC mandates time correction daily in USA/Canada. There was some discussion about dropping this in the future
How many clocks actually are based on the grid frequency? Between cell phones and battery operated clocks far less than half of mine care about line frequency. The primary exceptions are the ones in the microwave and the coffee maker.