Also interesting is that SEL is in the process of opening the first new PCB fabrication shop in the US in what I think is quite a long time. Since the last few decades have seen so much off-shoring of PCB manufacturing, it's nice to see someone bringing new facilities here (to small Moscow, ID, right across the border from Pullman). Unfortunately, the shop is going to be used only to build SEL boards according to the answer I got when I asked about general availability, but perhaps in the future they'll allow orders from other companies. Even so, it's nice to see a return to some of the vertical integration we saw decades ago with HP and others.
Wow this is a crazy coincidence. I was a brand new software engineer that actually worked on the original implementation of SEL’s SDN software. Was my first real job out of college! My name might actually be on a patent somewhere even though I was just a code monkey at the time…
I wonder how much it has changed since then. My former boss is still working on that project AFAIK, I should reach out to him…
I didn't actually work on the device itself; that was after my time. By the time I left, they basically just had the MVP of the SDN software itself done -- there wasn't even a device it was scheduled to be on. Sorry :/
I think most of us on HN think of Ethernet/Wifi/networking when we think of "IEEE", but there are whole other aspects/fields of EE that generally don't enter our consciousness regularly: the power systems work of this article is just one of them.
> SEL OT SDN technology solves some significant cybersecurity problems,” he says, “and frankly, it makes me feel comfortable for the first time with using Ethernet in a substation.
Sounds like an all-round awesome guy as well, significant philanthropist.
and this... party on dude!
> “I bought [ Protective Relays: Their Theory and Practice.] on the Thursday before classes began and read it over the weekend,” he says. “I couldn’t put it down. I was hooked.
I’ve been listening to the Catalyst podcast with Shayle Kann recently and it’s given me an appreciation of the importance of this type of work for the future of our planet. As we electrify everything the amount of work we need to do on the grid is astonishing and things like protecting equipment and identifying fault locations effectively can mean the difference between success and total collapse.
maybe? centralized sources are good for profit margins, but distributed and efficient systems are more how Nature works. We got here with a mix of both, keep mixing...
This recent paper from SEL engineers is interesting, it discusses potential issues with a rapid increase in high-current EV charging on existing power grids:
It also clarifies what is meant by an 'energy packet':
> "Simply stated: “Energy packets are precise measurements of energy exchanges, independent of system frequency and phase angles, and are computed and communicated at a fixed rate, with a common time reference” [5].
> "Power analysis software integrates 1,000 samples of 1 μs data into a 1 ms energy packet [5] [6]. The analysis calculates joules (watt seconds) of energy packets exchanged every 1 ms. For example, a 1-watt load consumes 1 millijoule of energy within a 1 ms period. Energy packets are calculated in the SI unit joules (J). Joules are converted into watthours (Wh) by a time-scaled 3,600 seconds per hour where 1 Wh equals 3,600 J."
Energy packets precisely measure energy transfer, independent of frequency or phase angle, and update at a fixed rate with a common time reference such as every millisecond
There's a call for you on line 1, someone calling himself Albert A. Stone wants to talk to you about this idea of a common time reference...
Packetisation of energy is an idea that's been bubbling away in my mind for a number of years, and I'm convinced that is the way of the future. It revolutionised data and in my opinion will (eventually) revolutionise energy, heralding a global "Internet for energy".
Imagine if sources could verify the link before sending each energy packet: no more electrocutions, electrical fires or damaged equipment. Imagine if in a domestic situation each energy packet was below the threshold that could damage a person? Electrical installations could become inherently safe, also meaning no need for specialist installers.
I get your point about universal time, EM waves and relativity. It doesn't stop data networks though, as packets include synchronisation, effectively establishing a local time for each link.
It's fascinating thinking about the analogies between data networks and power networks. What would synchronisation look like for an energy packet? What would a buffer look like, in case packets have to be multiplexed? What are the implications of being unable to copy energy packets? What is an energy packet? So many interesting questions.
Taking a system carefully designed to maximize power transmission across the country, and only sending power in bursts seems rather an odd design choice. You'd need to beef up all the transmission lines and transmission gear by a few orders of magnitude in current and/or voltage to make something like that possible. I'm not sure there's enough steel, aluminum, copper and insulators available to make that happen.
How would you store gigajoule "packets" of energy?
In theory, you could just send higher frequency AC or pulsed DC signal thru the wire (to get to the "one pulse is not all that dangerous" level), and with a bunch of ADCs discover every anomaly VERY quickly. But, now you're pouring high frequency signal into huge antenna, which means you probably need to change cabling to be twisted pair and recabling house is HUGE issue. And you have higher losses which means you'd realistically have to have power converter in every house for it as you couldn't transfer power at long ranges if it ran on several kHz
> Imagine if sources could verify the link before sending each energy packet: no more electrocutions, electrical fires or damaged equipment. Imagine if in a domestic situation each energy packet was below the threshold that could damage a person? Electrical installations could become inherently safe, also meaning no need for specialist installers.
If we assume sending device and receiving device both communicate how big energy packet would be and fail safe if it isn't, then sure, any interruption would be detected quickly, but it does nothing for cases where end device after the "power interface" has problems.
Also at least in US there is like 400 electrocution deaths per year, with only 20% from actual wiring [1], so it is a fight entirely not worth fighting, for residential at least.
Where I think it could be interesting is in high reliability equipment, where for example you might have power supply shared between a bunch of subsystems and you don't want failure of one component to cause brownout of whole thing. Sure, fuses do that but they are not exactly very elastic and don't send the signal about nature of the failure upstream.
A "power bus", where on top of delivering power subsystems can signal failure condition, or get signals (like "switch into power save mode, battery is low") might be interesting but if USB-PD is any indication it is FAR easier to make it into overengineered mess..
They are the sorts of questions that make it such an interesting problem. Maybe it's not as simple as turning it on and off? Maybe there is something to be drawn from the world of adiabatic logic? Maybe the answer is some sort of resonant system or waveform which "sloshes" energy from place to place instead of a hard on/off (yeah, related to AC). Maybe there is a system to smartly manage the boundaries between packets, to avoid unnecessary switching?
I don't think we have the answers (yet), but I think there will be benefits if we can find the answers. For example, we could truly leave the current generator/consumer model behind: just like the web enabled everyone to become a publisher, everyone could become a generator in their own right. No doubt we will then be talking about the Goolalisation of the energy network, where a theoretically distributed system becomes dominated by a small number of monopolies and people talk about how it's not worth running your own generator since Powersoft refuses to accept energy packets from smaller generators.
> Maybe the answer is some sort of resonant system or waveform which "sloshes" energy from place to place instead of a hard on/off (yeah, related to AC).
Most definitely not. You want to limit is as much as possible, as the reactive power (the "bounce back") still goes thru the resistance of the wire, generating losses. In fact big consumers often get charged when their power factor (the amount of energy "received" vs bounced back) is below a certain value.
Is this a control system for an electro-mechanical relay, or is the relay itself part of the innovation? I couldn't find info about that in the article.
For context, when power grid engineers talk about relays, they're not talking about physical switching of the electricity itself, but instead the control and monitoring system for the grid. Traditionally this was done using specialised electomechanical devices (like the common electronic relay, but with special functions/construction).
The relays control actual power flow on the grid indirectly, using devices like breakers, tap changers, etc.
This article is talking about the digitalisation of relays, which basically means microprocessors or adapting industrial PLCs to do the same basic functions as the electromechanical relays but better (smaller, less maintenance, advanced features like fault localisation, remote control, etc.).
Interestingly, some power grids have resisted digitalisation out of concern that new electronics will have unknown fault characteristics that could lead to blackouts. Take this in contrast to railway signalling, which has if anything a more severe fault condition (would you rather be in a train crash or a blackout!) yet digital signalling was enthusiastically adopted by almost all systems.
Yeah, the story I remember being told is that power companies originally didn’t want to replace their electromechanical relays so they installed the SEL boxes alongside them and used them as fault locators.
Over time SEL ended up taking over the market though.
They haven't completely taken over the market. The likes of Siemens, ABB, GE, etc. manufacture similar products. SEL is considered the best by many utility engineers.
