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All Of Argentina, Uruguay Without Electricity After Massive Outage

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Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#41

Post by sboctrl »

apthnz wrote: post #26
hfkajshfaks wrote: post #8

Earlier 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.

The EPRI Power System Dynamics tutorial is a free resource that is really solid https://www.epri.com/#/pages/product/1016042/?lang=en-US.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#42

Post by sboctrl »

amelius wrote: post #27
toomuchtodo wrote: post #24

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?

The reference frequency is interconnection wide. To bring a three phase ac generator online the terminal voltage, phase rotation, frequency, and phase angle must be within some tolerance.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#43

Post by throwaway5752 »

sergiomattei wrote: post #17
kasperni wrote: post #3

Argentina 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).

Puerto Rico was without power for months after Hurricane Maria.

They had massive physical damage from a powerful hurricane, their grid didn't just fail. Transmission lines and substations had to be repaired.

That is ignoring issues like Whitefish Energy among other things. Very different situation.

edit: yes, we know that nothing anywhere near comparable to hurricane Maria hit them.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#44

Post by MisterTea »

ics wrote: post #39
lugg wrote: post #7

Earlier 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.

I work on one of the densest power grids in the world (NYC) on the team which does emergency transformer replacements and can possibly answer questions about this. From failure to in service for a single transformer in Manhattan is down to 2-3 weeks. That includes design and engineering (my part), permitting, and construction. For fast transformer replacements we rely on two paths, either system spares (identical uni…

Neat job. I've always wanted to poke my head into ConEd's system and see the whole thing from behind the scenes.

Years back I remember ConEd was replacing two or three very large transformers down the street of a large venu I was working an event. Turns out we worked the same event the next year and amazing the same day ConEd again had the second transformer scheduled to moved into place. What an operation. Huge trailer from Bay Crane along with one of their giant hydraulic cranes. Was told the transformer weighed in at 240,000 pounds.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#45

Post by mrleinad »

Scoundreller wrote: post #15

How 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?

Tandil, Buenos Aires province: No cellular phone service for Claro (one of the cell phone companies here). Water service out for the entire day. Luckily I have a rooftop tank, but I got worried about running out of water if this outage went on for days.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#46

Post by 6thaccount2 »

MisterTea wrote: post #40
6thaccount2 wrote: post #34

Earlier quoted context omitted.

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…

Honestly, I know that entire procedure myself as it's listed on a few different sites, one being the wikipedia blackout article. Then again this kind of stuff interests me so I read up on it.

I'm not sure you fully understand, or maybe it's me that misunderstands what you're saying :)

Each utility generally has its own black-start procedures. One utility might start two diesel generators (only really used for black-start) and then slowly start energizing the path to various loads and other generators. That utility and it's parent RTO/ISO train on that scenario several times a year and have the procedure printed in a binder within reach.

Something I've found interesting is that many of these plans are ~35 years old and we're created before computers were super common place for these kinds of things. The point being people weren't doing graph and optimization algorithms to determine the optimal paths. There has been a little university research and national lab research into this recently and I've heard they've helped certain utilities that they worked with determine some improvements, which is always exciting.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#47

Post by da_chicken »

throwaway5752 wrote: post #43
sergiomattei wrote: post #17

Earlier quoted context omitted.

Puerto Rico was without power for months after Hurricane Maria.

They had massive physical damage from a powerful hurricane, their grid didn't just fail. Transmission lines and substations had to be repaired. That is ignoring issues like Whitefish Energy among other things. Very different situation. edit: yes, we know that nothing anywhere near comparable to hurricane Maria hit them.

Do we know that there's been no grid damage in Argentina? It is the middle of winter.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#48

Post by ics »

MisterTea wrote: post #44
ics wrote: post #39

Earlier quoted context omitted.

I work on one of the densest power grids in the world (NYC) on the team which does emergency transformer replacements and can possibly answer questions about this. From failure to in service for a single transformer in Manhattan is down to 2-3 weeks. That includes design and engineering (my part), permitting, and construction. For fast transformer replacements we rely on two paths, either system spares (identical uni…

Neat job. I've always wanted to poke my head into ConEd's system and see the whole thing from behind the scenes. Years back I remember ConEd was replacing two or three very large transformers down the street of a large venu I was working an event. Turns out we worked the same event the next year and amazing the same day ConEd again had the second transformer scheduled to moved into place. What an operation. Huge trai…

Heh, our most recent replacement a few weeks ago came in at almost 900,000lbs with oil. Depending on the speed of the replacement you can't always move the transformer dry because you need a certain amount of time between filling it and putting it in service.

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#49

Post by llukas »

agumonkey wrote: post #30
kabwj wrote: post #20

Earlier quoted context omitted.

>There is a common misconception that the number one driver of TV pickup is the boiling of kettles. In fact, this only creates a pull on the local network for a short period of time until the water has boiled, and can therefore be managed relatively easily, whereas flushing the toilet causes a longer surge at the water and sewerage pumping stations, and opening the refrigerator lets the chilled air escape, causing th…

dry toilets and solar concentrator kettles, yesterday

Or battery to handle short spike in demand (backed with gas turbine if risk of prolonged spikes).

Re: All Of Argentina, Uruguay Without Electricity After Massive Outage

#50

Post by ethbro »

amaterasu wrote: post #31
amelius wrote: post #27

Earlier quoted context omitted.

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?

I'm trivialising the problem, but whichever station energises the grid first becomes the reference. An operating grid has what may as well be infinite inertia (it isn't infinite of course), so new stations coming online must match it (or try and change the phase of the grid to match theirs). I visited a power station in Melbourne many years ago, and they have the shattered remains of a turbine and generator that was…

In the event that there's a phase mismatch, I assume that gets physically transmitted back to the generating device? (Mode subject to type of device) Or am I over-trivializing it?

E.g., will an out of phase turbine have a physical resistance against it, as a consequence of the rest of the grid?

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