Earlier quoted context omitted.
https://hackaday.com/2017/07/05/how-do-they-synchronize-powe... Phase is monitored on both sides of the connection, and high voltage contactors complete the circuit when tolerances are met.
But if you have a grid with a large number of nodes, how do you impose which node is running at the correct (reference) frequency and phase? Do the edges of the grid impose a master-slave relationship?
All Of Argentina, Uruguay Without Electricity After Massive Outage
31–40 of 146 posts
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#32Earlier quoted context omitted.
USA isn't in much of a better position. Large scale transformer blowouts are a nightmare scenario due to how long they take to replace / repair.
Even worse when a generator goes out (or is destroyed). It can take months to get a new one. Hope we don't have multiple generators go out at once. They're not just sitting on a shelf somewhere waiting to be picked up.
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#33Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#34Earlier quoted context omitted.
It isn't really though. A cascading failure can knock out an entire grid. The Northeast blackout is an example. A line goes out. while (there some lines are still live): The current redistributes itself among neighboring lines. Neighboring lines trip end BlackStart() BlackStart() is fun. Having your plants and grid down is like having a dead battery (plants use ~30% of the electricity they gen on themselves) and no o…
What do you do for a living, and how can I learn more about it? This stuff fascinates me and you've explained it really well.
There are also organizations like the RTO/ISO that also act like air traffic controllers for the grid by keeping it reliable. They also are usually responsible for committing and dispatching generation for dozens of utilities collectively to save money (by banding together, you need to carry less reserves or backup power and can leverage economies of scale). In North America these organizations are (CAISO, SPP, ERCOT, MISO, PJM, NYISO, and ISO-NE). All of these organizations practice black-start drills (I used to help run them) and have NERC certified operators.
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#35Earlier quoted context omitted.
Even worse when a generator goes out (or is destroyed). It can take months to get a new one. Hope we don't have multiple generators go out at once. They're not just sitting on a shelf somewhere waiting to be picked up.
how much redundant capacity does the grid have ?
One of the biggest issues is that traditional resources (coal, nuclear, gas) can run for long periods of time and in many places have a pretty reliable fuel supply. Renewables are great, but you could be generating lots of power one minute and then it's all gone the next hour. This causes a lot of stress on traditional resources which need to be ready to counteract this. Coal plants and gas plants were never designed for that either and it's causing issues.
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#36I was going to post this. Thanks. Looks like Uruguay, Paraguay, south of Brazil, Bolivia are also affected. Several million people. It’s raining, no internet, this will be a long Sunday. Also today is father’s day, will be a celebration with candles like in XIX :)
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#37CAMMESA administers the Argentinian electricity market, and they have data on demand [1] and grid flows. Compare the graph of flows on the 500 kV lines from 2019-06-16T07:00 local [2] to one hour later at 08:00 local [3]. For reference, see the prior day too, at 2019-06-15T08:00 local [4]. [1] http://portalweb.cammesa.com/Pages/ADemandas.aspx [2] http://www.cammesa.com/uflujpot.nsf/FlujoW?OpenAgent&Flujo%2... [3] htt…
[2] and [3] refer to June 15; [4] refers to June 16. Is your text correct? What can be learned from the numbers on the 500 kV lines?
http://www.cammesa.com/uflujpot.nsf/FlujoW?OpenAgent&Flujo%2...
http://www.cammesa.com/uflujpot.nsf/FlujoW?OpenAgent&Flujo%2...
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#38How resilient has the cellular phone network been in this outage? How resilient is the municipal water system in an outage like this? Do most people in Argentina and Uruguay cook with (piped/tank) gas or electric ranges?
Here in Argentina, municipal water is totally reliable (I've never heard of a water service loss due to a power outage), but the pressure in the pipes is so low that every individual house has a pump to raise the water into a rooftop tank. These pumps are invariably electric and powered from either the grid or, on the frequent occasions that doesn't work, a generator. Municipal water typically has service losses a few times a year, but not due to blackouts.
Gas stoves are far more common in Argentina than electric stoves, although my apartment has an electric stove, which has a short which electrifies the stainless-steel surface of the stove when it's turned on. Most people in and near the capital run their gas stoves and on-demand hot-water heaters from public-utility natural gas, supplied by local monopolies (state-owned in some cases). Propane cylinders are common in less-populated areas and in houses where the gas piping has been disconnected from the public utility, usually due to billing disputes or safety concerns.
Over the last few years, the utilities have been sandbagging gas reconnections after disconnections due to safety concerns, often allowing them to leave unprofitable customers disconnected for years at a time once someone has called in a gas leak, while they wait for the government price controls (which have fallen far behind our absurd levels of inflation) to be loosened, making those customers' business profitable again. This has been a significant reason for new installations of electrical cooking and hot-water-heating appliances. A court recently ruled against this practice, and so gas reconnections have been sped up lately.
Uruguay has much less use of natural gas, for regulatory reasons: gas appliances can only be installed indoors if the room in which they are installed has a window to the outside that cannot be closed, thus removing the risk of explosions in the case of a gas leak. Consequently in Uruguay gas stoves are almost unheard of, and nearly all cooking is electric. Many hot-water heaters in Uruguay are still the gas-powered tankless type that is nearly universal in Argentina, though. They're just installed outdoors.
(Actually, I'm not sure if the above information about Uruguay applies outside of Montevideo.)
I hope this information is interesting to you!
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#39Argentina is world’s eighth largest country. I find it mind blowing that you can have a power outage that covers the whole country (+ some more).
USA isn't in much of a better position. Large scale transformer blowouts are a nightmare scenario due to how long they take to replace / repair.
For fast transformer replacements we rely on two paths, either system spares (identical units, sometimes refurbished or like in kind replacements) and more recently mobile resiliency transformers. Resiliency transformers are trucked in on semis and can operate at 69, 138, or 345KV in our case. (There's some lightweight reading on them here: https://www.tdworld.com/overhead-transmission/siemens-introd...)
Re: All Of Argentina, Uruguay Without Electricity After Massive Outage
#40Earlier quoted context omitted.
What do you do for a living, and how can I learn more about it? This stuff fascinates me and you've explained it really well.
The user is probably a transmission level grid operator. These exist at most decent sized utilities (Entergy, AEP, Duke), although it is possible there is a TOP (transmission operator company) that is not the same as the utility. There are also organizations like the RTO/ISO that also act like air traffic controllers for the grid by keeping it reliable. They also are usually responsible for committing and dispatching…