Frequency drop on the utility

[al hildenbrand]

I'm guessing the Bladerunner reference is Ruetger Hauer's character Roy Batty, at the end of the movie. He's the last replicant that dies, but not at the hands of Harrison Ford's character, Deckard. Rather, Roy's preprogrammed shutdown (death) happens, and as it begins, Roy reminisces:

I've seen things you people wouldn't believe. Attack ships on fire off the shoulder of Orion. I watched c-beams ... glitter in the dark near Tanhauser Gate. All those ... moments will be lost ... in time, like tears ... in rain. Time ... to die.

 

[mpross]

freq

freq

Charlie,

I like that analogy, it is good. I am training for Ironman Wisconsin and ride my bike for several hours at a time (6+). Did you know that they actually make devices that give a power output for the rear wheel of a bicycle? They really help athletes to train for hills and other challenges, and to show improvement.

Also, I think the statement "The frequency changes in reaction to load changes" makes more sense to me than "The frequency changes slightly to keep the system in balance" because it gives a better cause/effect relationship.

I was thinking of a "Balancing Authority" that makes sure the system is balanced (gen/load), when I said this: "We keep the system in balance to keep the frequency in check", and I agree with all you have written. This is a great area of study

Here is a good reference: http://www.naesb.org/pdf2/weq_bklet_011505_ace_mc.pdf

-Matt

 

[mpross]

voltage stability

voltage stability

Another way that is used to control the voltage in an area is with the use of reactive devices.

When there is not much load, say early in the morning, reactors are switched on in order to keep the voltage levels down.

In the case of peak-loading, voltage levels can be maintained by taking off the reactors, and switching on large capacitor banks.

-Matt

 

[don_resqcapt19]

Matt,

Is this correct? Should it be the opposite?

It can't be the opposite. The utility doesn't have any real control over the load. As the load changes the supply system must adjust.
Don

 

[mpross]

control of load

control of load

Actually, in extreme cases, the utility has the ability to perform "load shedding". This is used in cases where there is chance of voltage collapse, and also in the case of underfrequency.

Have you ever visited an energy control center? Operation of breakers, switches, reactors, caps, etc,... is a 24/7/365 process (all at the click of a mouse). The transmission/distribution grid is constantly being changed or worked on, and thus the flow of power has to be re-routed through different lines.

Sure, I would say that the load is a significant factor, and always changes! Also the weather, generator trips, power interchange with neighboring utilities, and many other factors affect the frequency.

-Matt

 

[don_resqcapt19]

Also the weather, generator trips, power interchange with neighboring utilities, and many other factors affect the frequency.

The other utilities are a big part. The complete system within any of the three US interconnets must operate at the same frequency as they are physically connected.
Don

 

[don_resqcapt19]

You can download a program to look at the Western interconnect frequency in real time here.
Don

 

[mpross]

Yep, it really is the most complex machine that man has ever built. Well that is what they say on TV

I actually work at a control center, in the system operations dept. (for now anyway) so I get to see a bunch of cool stuff. There is always something cool lurking behind the scenes!

-Matt

 

[robbietan]

frequency is also maintained at 59.7HZ to 60.3Hz. This is to protect the generators from overspeeding, i.e. trying too hard to compensate for an increased load.
Generator excitation is used to correct the frequency and also corrects the voltage.