Power plant people - can you explain this anomaly?

The closest that i have experienced to what you describe was on a steam ship that was experiencing a feed water pump casulity . The ship was av UNREP Tanker and had another ship along side at the time. This meant that we couldn't respond to the casulity immediately until the other ship could disconnect and break away. As a result we lost a lot of boiler pressure during what seemed like an eternity but was probably no more than a couple of minutes. During low pressure operation the turbo generators started surging and the voltage output swung wildly. The lights started to wink on/off at about 1to2second intervals but we never lost power completely. We were stripping the buss of load and managed to not trip a main breaker nor reverse power relay on any of the three SSTG's.

I can't speak for your local power plant but may only suggest that some significant event was underway during that time. Why your portion of the grid remain connected to the power plant is anyones guess perhaps breakers didn't trip and plant personel were busy handling the casulity with a boil to notice. Considering the time period i also would not overlook a mechanical failure of a breaker to fully open or fail to open. Generator motorization would pull the entire buss down and its possible that the generator was kept providing some power so as to not completely drag the buss down and cause a cascading trip of other plants. Whatever steam or water flow was supplied to the turbine and as you describe power phase differences would effect the buss voltage.

Also consider a casulity to a voltage regulator causing the load on the effected generator to fluctuate.

Those are the best guesses that i can come up with for an event so far back in the past.

EDIT:

USNS Ponchatoula T-AO-148 Neosho class oiler. 3rd A/E 1985-1987 MSCPAC

It's most likely a result of rapid switching that occurs in the power grid due to ground faults in power lines. Since power isn't stored, it has to be redirected somehow whenever a path is interrupted for whatever reason (such as when a tree falls on a power line). This can cause a temporary surge or drop in voltage in connected power lines that are still functional. This is what is happening everytime you see your lights flicker for a split second every once in a while. Sometimes, these switching actions can cause a chain reaction of other grounding problems which, in some cases, requires power grid operators to take further actions, and you end up with the type of interruption you had experienced.

That massive blackout the entire northeast experienced a while back started off in pretty much the same simple manner.

Hydro might offer a clue. eg Ben Cruachan Power Station in Scotland can go from "spinning reserve" (turbines turning in air) to full load in 30s. It'll be faster going to a partial load.

Perhaps if a hydro turbine was on load, the penstock might start gulping air down it (a seich on a lake?) or some malfunction of the valves/control system result in a drop of pressure, and so lower generated power, Once the air passed, or the values reopened, generating capacity should start building again.

If the control system wasn't damped properly, and the system will respond fast enough, a system could begin to oscillate, as it tries to "hunt" a set value- overcompensating by going high too hard, then as value too high overcompensating by going going low too hard.

Voltage swings are very common in domestic systems. It's analogous to pressure swings in a pipe of water, where you might have several downstream destinations, all feeding off the pressure of the pump delivering the water. You can call the pump the power plant; it supplies the pressure (voltage) to push the electricity potential from a high pressure to downstream lower pressures (your home). If, at any time, the demand downstream is driven up considerably in a short amount of time, the entire circuit of flow is affected instantaneously (physical property of flowing systems, pressure swings are transmitted throughout) and you in theory have 'opened an additional valve downstream' by increasing the demand for the flow of electricity. The corresponding pressure drop (analogous to voltage drop) comes from the pump, (or electric plant) having to adjust its throughput to maintain demand.

Where a fluid system would see pressures swing in the downstream sources of a pump, an electrical network would see voltage swings (as manifested by blinking lights or your analog meter bouncing around). There may have been increased demand as many homes turned on their A/C units all at once, or the power plant may have had some interruptions with their water streams that drive their turbines. Could have been any number of issues at the plant, or with downstream demand.

Hope this helps...

Hi,

you can find a free download of Age of Empires III here: http://bitly.com/1p0vPBF

After having used this game for the last 8 months, I can say that this game is simply a normal extension of the Age of Empires games. I have used the last version of this game, and I think this version is an progress in virtually every way. The weapons are very powerful, and the battles are very stunning. All I can say is that this game is really good. It is one of the best strategy games I have ever played.

If this really happened, there was a significant malfunction in the system.