15 Comments
Jun 22Liked by Meredith Angwin

Lovely piece of work. It's enjoyable to read something that instead of being sexy and bold, is more descriptive of energy transmission at the ground level. Kudos for taking the time to break down Texas' inverter based failures through exposition that enlightens readers rather than creating simple angst. Well done and thank you.

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Thank you!

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Thank you, I was unaware of the passive islanding mode in inverter controls. Little info, when San Francisco forced PG&E to shut down their thermal generation in the City limits, it left them short on voltage support. PG&E contracted with Trans-Bay Cable to build an under bay DC cable to act like a generator and provide the needed voltage support.

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Jun 22·edited Jun 23Liked by Meredith Angwin

Excellent work, really. And yes, power engineers and their recommendations need to be taken very seriously by political decision makers.

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Jun 23Liked by Meredith Angwin

Synchronization is one of many extra complexities with adding IBRs to the grid. And grid stabilization to maintain 60Hz on the dot is very crucial.

An older power engineer I work with (my mentor) tells me often about the days of him working for the local utility. Before everything was digital, they had an old needle-and-paper printout of the grid frequency plotted over time. He said the straightness of that line, no matter the time of day or season of the year, always amazed him. It also highlights the other big advantage of baseload power - human control. We can dial up or down the parameters needed to maintain 60Hz no matter what. When the grid is weather-dependent we are adding much chaos to the grid that now has to be managed with more equipment and more human brainpower. But as stated so well in the article, there are many issues in tying all this equipment together that doesn't shake out until a problem occurs. I don't really think it's wise to make our grid the petri dish for this experiment but here we are.

Thanks Meredith for the more technical posts!

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Hey Electric Grandma, thanks for reminding us just how complex the grid is. My non-engineering mind will need reread this piece a couple of times, but it is great to know you are watching over this effort to modernize our grid.

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Jun 25Liked by Meredith Angwin

I understand the relevance of synchronous condensers as they are used to maintain a stable phase (i.e. remove phase jitter by absorbing reactive phase differences using a huge rotational energy inertia). What I don't understand is why electronically controlled inverters couldn't use a separate grid-supplied reference to maintain a tight phase control for their PLLs. Is that possibly something still being worked out?

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Ike. As I understand it, a regular IBR (not grid-forming) takes its frequency and phase from the grid it is attached to. Its PLL abilities and so forth are for times when the IBR can't get an effective grid reference. So that is why it isn't using a grid-supplied reference for its PLL.

I think. Merely think.

I am NOT an electrical engineer, so I am uncertain in this area. I hope some real EEs will chime in and answer your question. And quite possibly, correct what I have written in this response!

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Thanks, yes I figured you would likely not know but you have a lot more contacts in the electricity generation industry than myself. ;) Note that the grid reference I'm suggesting wouldn't be transmitted via the grid itself, rather via the Internet possibly(?) or dedicated radio frequency and would need to compensate for reference time delays as well as grid reactive elements.

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Jun 23Liked by Meredith Angwin

What is the difference between a condenser and a capacitor ?

A condenser and a capacitor are essentially the same thing. They are just two different names. Capacitors were called condensers earlier. The term "condenser" is still used in the automotive industry. A capacitor is a electric component which consists of two conducting plates separated by a dielectric. Just another way to keep the VAR constant in smaller circuits

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Well, yes and no. The old name for capacitor was condenser, and the term condenser is used for synchronous condensers. However, the grid operators are not trying to be old-fashioned. (My opinion.) I think they are trying to distinguish between synchronous condensers (big spinning machines) and capacitor banks. Banks of capacitors are also used on the grid.

I think the wikipedia article does a good job of describing the different possibilities for the grid.

https://en.wikipedia.org/wiki/Synchronous_condenser

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Jun 25Liked by Meredith Angwin

Exactly. A condenser is indeed another term used to describe a capacitor. The term is also used to describe a means of turning vapour into liquid form. But a synchronous condenser is yet another animal. Essentially it is a huge mechanical PLL, the inertial energy absorbs any phase differences (VAR variations) so as to maintain a stable output power to the grid. So it connects across the output (as a capacitor would) but absorbs reactive power differences as opposed to simply absorbing electrons as a capacitor does.

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In building their model of New York State's grid, New York State officials have treated this grid as if it were an example of "non-complex" physical system though this grid is actually a "complex" physical system, where a "complex" physical system exhibits one or more "emergent properties," each of which is a property of the whole system and not pf the separate [[arts of this system, whereas a "non-complex" exhibits no such properties. This mistake has led New York State officials to believe their energy policy of decarbonizing New York State's economy does not destabilize New York state's grid though the opposite is true. These officials make the same mistake in regard to Earth's climate system in concluding that decarbonization of New York State's economy is necessary for avoidance of Catastrophic Anthropogenic Global Warming. As methods for construction of models of "complexa" physical system are available, for New York State officials to base public policies upon models of physical systems that mistake "complex" physical systems for "non-complex" physical systems is an avoidable blunder.

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RemovedJun 24
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Terry, I have known you for a long time, and I don't want to lock horns with you. I have never agreed with your overly complex analyses of how dangerous nuclear energy is.

More importantly, I do not allow comment threads on my substack to be hijacked for someone else's agenda, in this case your anti-nuclear agenda.

In short, your comment has been removed and you are banned for 24 hours. If you try to hijack a thread again, I will ban you permanently. I would be sorry to do this for someone whom I have known so long, but I will do it.

You have your own substack. Post your thoughts there.

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