follow the money... who has stock in power conditioning/filter/regulator companies
Posted on 06/24/2011 11:36:30 PM PDT by John W
WASHINGTON — A yearlong experiment with America's electric grid could mess up traffic lights, security systems and some computers — and make plug-in clocks and appliances like programmable coffeemakers run up to 20 minutes fast.
The group that oversees the U.S. power grid is proposing an experiment that would allow more frequency variation than it does now without corrections, according to a company presentation obtained by The Associated Press.
Officials say they want to try this to make the power supply more reliable, save money and reduce what may be needless efforts. The test is tentatively set to start in mid-July, but that could change.
(Excerpt) Read more at msnbc.msn.com ...
America’s power grid: reliable electricity 24 hours a day, 7 days a week.
One of the few things left in America that still works correctly and separates us from third world cesspits.
Obama is trying to destroy the power system by shutting down coal mines and coal generators.
But that’s not working fast enough so now they are going to “fix” a system that’s not broken.
We had an acre of CNC tools running, and lost one phase. Some of the parts were titanium. It took days to recover, and still a lot of scrap was made.
Thanks for the link. Very interesting and revealing article.
That makes me think of the paper mill I used to work at when they had their own generators and the issues syncing with public utility power when one was restarted after being down. Might make that even more difficult than I recall unless something has changed over the years.
Montgomery County, MD, eh not so much.
In one of the ten richest counties in the USA we have Pepco, which for the last two decades has been striving for third world capability. We might very well have the highest full house back-up generator per housing unit rate in the country.
Piss poor mgmt incapable of fore seeing the rapid growth which should have been evident from construction permit applications both in housing unit quantity and increased load per unit. Add the increased load imposed by consumer electrical goods on the aging existing housing stock coupled with the ultra liberal political structure it's a wonder that we don't have more outages than we do.
The same circumstances hold true for the Northern Virginia areas that Pepco serves.
Where I live transformers blow with regularity 5 or 6 times a year. (That's both pole and ground installations installed in the 60's.)
The local Lowe's starting selling 100 count AAA and AA batteries that coincided with the introduction of cheaper and more efficient LED emergency lighting. And they are sold out almost as soon as they hit the shelves. Now clerks just nod their their heads knowingly and say, "Pepco, right".
Well, this experiment may result in you having a lot of company across the nation. Probably some of the brilliant minds behind this live in those territories and don’t realize how well the grid works in MOST of the rest of the country.
follow the money... who has stock in power conditioning/filter/regulator companies
Just so,as both the DC suburbs in MD and VA also have the highest concentrations of upper tier Gov employees and their consultants and lobbyists. Not only are they willfully ignorant, they truly flat out don't care about the rest of the country. Paraphrasing Marie Antoinette, "Black outs? Let them buy generators."
***A lot of machinery relies on induction motors who’s running speed is reliant on line frequency.***
Further more, all generators on the same grid run at the same frequency, 60 hz. They are electricly tied together. The variable range of frequency is 57.5 to 62 hz. Anything under or over these ranges will automaticly trip off the generating units.
To send power from one grid to another the generating units must convert the AC electric load to high frequency DC power and the receiving grid must use a “static converter” to return the DC power to AC in their frequency range.
Actually, at the beginning of the electric era, the frequency was zero cycles per second. ≤}B^)
Later, several (nonzero) frequencies were used, such as 16.666... and 25 Hz. For heavy industrial uses such as electric railways, some of those low frequencies are still used.
[[Being a EE but not of the power variety, I have often wondered about the engineering considerations that resulted in the use of such low frequencies for industrial purposes even after consumer power in North America was settled at 60 cycles.]]
Perhaps there are some devices on the grid that are not up to specs, and by varying the frequency they will be able to locate them?
***I’m thinking their idea is that they want to boost the line voltage to compensate for I2R loses caused by peak demand. The only way they can do that without changing the infrastucture is to run their alternators at a higher speed, which up’s the line frequency.***
Can’t do it on a generator. They are designed to run at only 60 hz. To boost voltage you increase the magnetism in the generator rotor and the Hz never varies.
In summer you have lots of VARs (volt amp reactive) due to the increase of induction motors on the line. To reduce the VAR load the dispacher can add capacitors to the line load reducing the VAR load. When he runs out of capacitors then the VAR load will increase no matter what you do, even to the point of possibly melting down the 3 phase power lines.
I think it would depend on how fast the frequency could fluctuate and how far. The physics of a large ensemble of generators feeding the grid place considerable physical constraints on these two quantities.
If the claimed limit of 14 seconds per day is a reliable indication, that works out to 162 parts per million. Unless your motor-driven industrial system is doing audio or video work, that amount of deviation is probably trivial.
This brings to mind the time in 1967 I was watching a TV network show originating, on film, from New York City. Suddenly, the image went dim, slowed down noticeably as was evident from the sound track, and then went dark. A few seconds later the local station put up a network trouble slide. This was the great 1967 northeast blackout. The projector was equipped, as most are, with a synchronous motor, so I was actually seeing, for a second or two, the frequency of the entire northeast grid sagging well below 60 Hz before going away completely.
This is about as poorly-written an article as could be expected. Obviously, the journalist doesn’t have a grasp of the situation or the proposal at all.
The standards for operating frequency remain the same - normal operations are within 0.05 HZ of 60 HZ, and typically run from 59.98 to 60.02. It fluctuates during the course of the day as customers bring on loads and generators adjust output to compensate. If the generation output is higher than the load, the frequency will tend to rise as generators speed up. If the load requirement is higher than the generation, the frequency will tend to fall as generators slow down.
The requirements to operate within the same bandwidth remain the same. Automatic load shed requirements at very low frequencies still exist. Automatic Generation Control response characteristics remain the same. Reporting requirements for wide frequency excursions or sustained operation outside of normal limits (typically +/- 0.05 HZ) remain the same.
What is changing is the mandatory requirement to correct accumulated frequency error. When time error accumulates + or - 10 seconds, a time error correction is called. In time correction, the standard frequency is raised 0.02 Hz if the time is negative (slow) or lowered 0.02 Hz if the time error is positive (fast). This allows older synchronous clocks to remain at the correct time.
Fact is, there are very few older synchronous clocks around any more. And odds are, nobody would notice the 10 or 20 second error that had accumulated over time even if there were.
Thats an interesting story about 1967.
So, is there any effect on 60 HZ equipment from this? Corrected or not?
Yep - in my mind, that's a symptom that FR is still sluggish and somewhat broken. Currently the FR clock is running 13 minutes ahead of real time. I'm hitting the post button at 8:33 am.
You nailed it Joe!
Laminations in electric motors and transformers are sized and designed for 60 cycle.
This will probably be a big boost to the power correction industry. Gonna cost a lot of money to “clean up” the power coming into your plant, office, etc.
Headed for another disaster no doubt. After the last one the clock was ok for a very short time upon the fix. Maybe someone understands the connection between the site being “clocked” and the seemingly inevitable collapse-if there is any?
Probably the simple fact that 60 cycle power happens to occur when the AC generator runs at 3600 RPM (1800 RPM for a 2-pole setup, and I've seen some really weird operating RPM ranges for some old hydro generators with many poles). I think that 60 was chosen simply due to the capabilities of rotating machinery at the time that it became "standard".
BTW, operating a generator under load much above 60 cycles will most likely damage the turbine. They're built to run at 60, and much deviation could result in internal resonances that will cause turbine vanes to literally break. There's a lot of engineering that goes into these things, much more than I understand.
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