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Google Challenge Results In Astoundingly Efficient Inverters
AmiMoJo writes: A few summers ago, Google and IEEE announced a one million dollar prize to build the most efficient and compact DC to AC inverter. It was called the Little Box Challenge, with the goal of a 2kW inverter with a power density greater than 50 Watts per cubic inch. Typical solar inverters have a density of about 5 W/cubic inch. Now the results are in, with the winners hitting 143 W/cubic inch using GaN transistors, and two other teams meeting Google's goal.
The world is a slightly better place.
I am very small, utmostly microscopic.
This doesn't seem to be about efficiency at all, but rather about power density (how much power can be converted in a particular cubic volume.)
Not that small isn't a worthy goal, but efficiency is important in any application where available power isn't both free and copiously oversupplied.
I've fallen off your lawn, and I can't get up.
Is that you Thomas Edison?
Stop electrocuting elephants!
I think he forgot the /sarc at the end of his post.
If you're scared of your govt then you need to further restrict its powers
Vote 3rd Party in 2016 and beyond
Are guys fucking serious?!?
If you really want to use your old units, why not horse power per cubic inch?
Does any one know what power density the inverters for HVDC transmission lines achieve? I know that this is not a comparable use case, i'm just interested.
Gallium Nitride transistors have a lot of nice characteristics, but low yields and high costs have slowed their introduction. Two tiny laptop chargers, the FinSix Dart and Avogy Zolt, were said to use GaN transistors. The Dart still hasn't shipped, a year past its claimed release date. The Zolt has but is apparently using older Silicon Carbide-substrate transistors instead (Also see here.) (I received my Zolt recently and it is working well.)
It won't be a surprise to anyone following this technology that it can make inverters more efficient - that's what FinSix and Avogy have been claiming/demonstrating for two years at least.
If you don't understand why this isn't going to happen, you need to be kept away from grid design.
Replacing the AC network with a DC network would mean either replacing or substantially modifying the entire fleet of existing generation plant, all distribution and conversion equipment, all industrial equipment powered by electricity and most appliances. You might well be right that you can achieve better efficiency in a new network with DC than with AC; when you have to replace the entire electricity system, from spinning turbine to phone charger, it just ain't gunna happen.
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Genuine question. The web site talks about inverters being 1-2 cubic feet in size, and it wants them smaller. I understand that smaller is better. What's the application that requires a 2kW inverter smaller than that?
I think he forgot the /sarc at the end of his post.
You are assuming GP male. This kind of sexist assumption is exactly the type of thing that needs to be stamped out in the industry.
Now if you need me, I'll be in my safe space. /sarc
We should not be generating AC power in the first place. DC is much more efficient.
Perhaps not now, but way back when, AC was required because transformers could only work on AC, and people wanted high voltage, low current to minimize power wasted in the pylons' cables.
There's probably a joke to be made at your expense, here.
We may have just hit peak Google. Three stories in a row.
You are welcome on my lawn.
Personally, I read it as "Anonymous Coward by its very nature inefficient".
Mimetics Inc. Twitter
Another nice improvement the winners made above the requirements was that Google asked for 230 or 240 VAC output, but the winning device provides 240 VAC split phase, which means it can also be used to provide two legs of 120 VAC. Not that it's terribly hard to add a 240 VAC -> 120 VAC transformer, but with this design there's no need.
Cubic inches?! So this isn't a project intended to be looking beyond the borders of one country?
-Matt
I think that's the point - to remove some of the challenges not everyone else has so they have the opportunities everyone else does.
Whether any given program actually achieves that is of course debatable.
Thanks to all the AC for clarifying why Trump might become you president....
As a side note: positively discrimination on a goal oriented challenge would be beside the point, after all you want the maximum of "what ever" from the winner...
But not going through a phase of positive discrimination has two drawbacks, you get less talented people from the discriminated group, and you give the illusion to a whole bunch of idiots in the advantaged group that they are actually worth something in their chosen activity, instead of letting them either try harder, or change business.
So as defined in the Hacker's Dictionary Loose Loose !
I'm still puzzled by the economics of these prize driven challenges. Look at the winning design: (pdf) . R&D costs of it (including expertise, etc) well exceed $1mil. And having a lot of teams working on their designs... Assuming that there are at least 3 other good teams means then expected payout is laughable $250k...
As a professional, I expect to be paid for the work I do for hire. Sure, some things are done for fun, but building entire product is rarely is... Like, look at the open source software, for example: many parts of Linux OS are interesting and fun, others are not - so if you need them to be done, you better be ready to pay.
Another angle: even if you don't need money, there are plenty of engineers who do - google can afford paying for these things full sticker.
If you started with nothing and had to buy all of the tooling and equipment, recruit people, etc., I could see this easily costing $1 million, but the winner is an inverter company. They already have all of the tooling, equipment, expertise, etc.
They "just" needed to optimize one of their existing designs for size. Also, they only needed a working prototype, not a full production model. How do you figure that costs a million dollars?
I would assume that the parent is talking about on a residential basis (Excerpt from Little Box Challenge Website "The problem is household inverters are too big") not on a utility scale. If that is the case there is some reasoning to keep the power DC where it is reasonable (TV's, LED lights, etc), A KW scale DC-AC inverter is still however necessary for high draw appliances which are unlikely to run off of DC anytime soon. Homes in the future will likely run a mixed AC/DC system, using power from the grid (AC) and from residential solar/wind (DC) to feed AC & DC wiring throughout the house.
Sounds like Google had very specific design requirements and didn't want to spend the money in house doing development. So they dream up a contest and offer a cash prize. Meanwhile Google saves way more than the $1 million they paid out.
Only the State obtains its revenue by coercion. - Murray Rothbard
"Google Challenge Results In Astoundingly Efficient Inverters"
Sooo, what is that number? I can't find it anywhere.
Commercial PV inverters are about 97% peak, 93% average. Not a lot of room for movement there.
Hell if I remember correctly half of Japan runs at 60Hz and the other have at 50Hz due to a standards change years ago, and they've never been able to convert even that due to the monumental effort required, and that is AC to AC!
Though I expect the use of things things would be for Cars and Homes, not entire network conversions...
Watts per cubic inch (cm or whatever) is just one measure. It's a fine target for aerospace and automotive applications. But it is of secondary importance for fixed installations like solar. Here, the efficiency I'd be interested in is power conversion efficiency. Particularly across a wide range of loads. And I'd like that efficiency to come at a reasonable price as well. Where I can evaluate the dollars spent to save a Watt of inverter loss vs the dollars per Watt that a larger solar panel will cost me.
The size of inverters used in solar installations has already come down to the point where small single inverters per panel are available. Once these units have come down to the size of a paperback book, their physical volume is no longer much of a factor compared to the panel size.
Have gnu, will travel.
It must have been something you assimilated. . . .
As you did too, taking an opportunity to make a point is fine
We should not be generating AC power in the first place. DC is much more efficient.
I look forward to your design that can convert generator output to 300kV DC for long distance transmission.
AC is very efficient for transitions without using exotic equipment. Barrier to entry is much much lower. And efficiently transmitting DC requires very dangerous voltages.
Because registering a team is somehow hard for minorities or women? The fact they had to use the internet or english? Please describe a change faced by these groups that a white male from Appalachia would not also face?
No sir I dont like it.
It's not like it's a secret who won the competition, and you know the winners are about to seriously upgrade their jobs. There's also prize money, but arguably, the fact that you can get a job pretty much anywhere with this on your resume is the bigger reward. There are lots of incredibly competent people in the world whose competence is underutilized by their employers. If contests like this bring out their A game, everybody comes away better off.
Are the results open for everyone? If so, then they're also paying for something which everyone can (potentially) benefit from
You know the same thing could have been (and was) said about the switch from an analog phone system to digital. Every phone, every piece of switching equipment, every repairman's kit had to change -- all at enormous expense. It paid for itself though, by increasing profits (companies could charge for the new services that were made possible). All it would take is for some upstart startup to begin hooking up DC power in some new neighborhoods to get the game going. I don't even know if that would be legal now in most places though. The entrenched power monopolies would be a big obstacle to overcome.
The original parent was obviously speaking with tongue-in-cheek to mock the whole concept and your reply while being modded as a troll was completely genuine.
You want the truth? People can't handle the truth!
Google must have gotten Timmay a new wheelchair.
or wired the current one to give 240VAC shocks to the occupant.
There is no right to feel safe thru security vaudeville at the expense of everyone's freedom, privacy and tax money.
I think someone is trying to be too politically correct. For ages it's been assumed that "he" and "man"/"mankind" may be used in a generic sense to refer to everyone, because English is already cumbersome enough as it is without having to write out "he or she" just to satisfy the hypersensitive knee-jerk reactionists out there.
The Christian Right is Neither (Christian nor right). See: Matthew 23, Matthew 25, Ezekiel 16:48-50
Cock, alternating, cycles... I'm pretty sure there's a retort about how your dick hertz in there somewhere.
"So long and thanks for all the fish."
The top 18 finalists' designs are available here: https://www.littleboxchallenge.com/
The winner's design is here: https://www.littleboxchallenge.com/pdf/finalists/56568-Tech.pdf
"GaN transistors have many very interesting electrical characteristics (low Rds_on, low
Qgate and Cds, ultra low Qrr); these create technological advantages over current MOSFET and
IGBT devices (small size and low production costs). Unfortunately, they also have serious
drawbacks due to their very fast switching characteristics: they are challenging to drive and
require sensitive electromagnetic noise management. Another pitfall is the high voltage drop due
to the reverse current when the GaN is turned off. The solution selected to overcome these
difficulties is to control all the GaN transistors using soft switching for the entire operation
range"
The only problem with this specific item, is that it's doing exactly the opposite work of what google was looking for. This is an AC -> DC converter, which have been improving a lot in the last years, and they wanted to improve the DC -> AC path.
What you linked to is a battery charger that takes 120-240V AC and outputs 24-60V DC, not an inverter that accepts 300-450V DC input and outputs 240V split phase AC. These are very different things.
And when AIs start objecting we'd need to write she/he/it.
I think we've pushed this "anyone can grow up to be president" thing too far.
Slobodan Cuk of "Cuk's converter" fame (https://en.wikipedia.org/wiki/%C4%86uk_converter) is not very convinced. From the commentaries:
I could not find anywhere in a number of public announcements the efficiency achieved for any of the top three designs! It appears then that efficiency was NOT a criterion at all in Google's Little Box challenge, but only Power Density and resulting total volume!
I spent 42 years in Power Electronics with the main goal of improving efficiency and reducing magnetics size tenfold without increasing switching frequency! Both are the prime factors enabling smaller size and weight! Without the efficiency objective and novel systems solutions, the glorification of the power density alone sends absolutely wrong signals to Power Electronics industry and misleads young engineers as to what is really important! This is one man’s opinion, I invite yours!
Dr. Slobodan Cuk
There are numerous devices for making DC directly from mechanical motion. Tesla invented a low voltage device ("Unipolar Dynamo") which is unfortunately very inefficient. There are also very high voltage DC generators like the Wimshurst machine that induces an accumulation of charge and the Van de Graff generator which uses the simple technique of transporting charges on an insulating belt.
Contribute to civilization: ari.aynrand.org/donate
100,000 3 volt power supplies wired in series.
Ten 30kV DC CRT power supplies wired in series, from discarded televisions. Recycle!
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For a given amount of power, DC can use lower voltage and/or lower current than AC. That means less aluminum or copper, or towers that aren't quite as big. DC doesn't suffer from skin effect. (Skin depth for aluminum and copper is about 10 mm at 50/60 Hz.) One disadvantage of DC is that arcs aren't self-quenching.
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We need some kind of automatic bounds checking for sarcasm so that these kind of comment overflow attacks can't happen.
You found all 8 female engineers!! Well done!!!
When there's 1 of you and 17 others hitting or eeriely friendly towards you- it's creepy.
When you travel with your advisor and they want to go out and get drunk with you, it's creepy.
But I think you pretty much set the standard so I'll just use your words.
ALL UNWANTED behavior or UNWANTED attention is creepy.
I duped the unwanted to make it clearer.
Cheers.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
I think this discussion is pretty good evidence of the challenges facing minorities in tech. It's not about registering, it's about getting to the point in one's career when one can register. That is the part more difficult for under-represented groups. This has nothing to do with blame or vengeance, just fixing something obviously wrong.
I do not see that as much different than a white male who grew up in the poorest parts of the US. In many ways a member of a minority or female in the suburbs has a lot more access and opportunity. To often we make the bad leap from correlation that some group has statistically less representation in a field to that they are somehow excluded from that field. Asians/pacific islanders hold nearly twice their percentage in the overall population in new STEM degree's. American Indians/Alaskan Natives only about a third. In any event you have to look as why people are not choosing that field of work, poor education, societal values that do not value those sorts of fields, lack of role models, etc.
In any event thats far far out of scope for a contest to deal with, you can not fix not having enough minorities or women with the appropriate skills as part of a less than two year competitive event. If anything you realy should not give anybody special treatment in a competitive event only the results matter. Initial outreach is probably as far as you can go without biasing towards those minorities or women. Longer term unbiased outreach to younger populations could even things out in the long run and remain fair.
No sir I dont like it.
As far as I know they didn't. They didn't correct for creepy fellow male students mobbing them nor for creepy professors hitting on them or for creepy co workers mobbing them and hitting on them once they graduate either.
Yeah, the same guys that can't get a date to save their lives. They come across as creepy because they don't know how to talk to women, but I guess it is more fun to make fun of the kids with handicaps than to understand that very likely you are talking about people with autism.
A scary finding of the questionnaire was that women reported their high school guidance counselors were very non-supportive of their decision to study engineering. Non-supportive is a nice word, because I got long letters that talked about how they were actually discouraged by people in their high schools. There seem to be many high schools in our country which discourage women from taking advanced math and physics courses, and, in fact, there seem to be very few women who were physics teachers in high school.
When I was in Calc and Physics (ap and regular), the class was half women. My Calc teacher was a woman, my physics teacher was a man, so what? Women far outnumber men in teaching positions, should we start correcting for that next? I'll bet that those same guidance councilors would discourage men from teaching or going into nursing, where is all the outrage? Considering my office (systems engineering) is half women, I don't see an issue, if you personally run against sexism, you should move around it or deal with it, not complain on an internet forum where there will be no effect on the problem.
They were expected to take care of household duties any way.
That is an issue in the household, it sounds like she chose the wrong husband. There are guys that would love to stay home and take care of the house and kids, those guys are considered creepy by woman like you because they are more sensitive instead of being alpha males.
And having a child is a challenge - especially since men don't get maternity leave.
It depends. When men work in white collar employment, many companies offer paternity leave, but I would be seriously surprised if anyone offered maternity leave to a man, as that would be the wrong type of leave.
http://dictionary.reference.co...
APK likes to ask for responses to the same things over and over. Maybe he just likes the responses?
Amazing. I was quoting from responses to a survey of 4,000 female engineers.
The response- all from males- allege there is no problem for female engineers.
Those silly female engineers just don't understand apparently.
Keep kidding yourself.
She was like chocolate when she drank... semi-sweet at first and then increasingly bitter.
Pregnancy. Rape. Institutional racism/discrimination. The complete obliviousness of the average white male to their privilege relative to lesser privileged groups to the point where they have to ask such a question as this.
This comment is my opinion and does not represent an official position of Donald Trump or others I do not work for
We should not be generating AC power in the first place.
And how exactly do you propose to that? (*facepalm*)
Cost free eBook I read (by iBook/Kobo/Amazon/ObookO/Gutenberg etc.): "The Green Odyssey" by Philip Jose Farmer.
So pregnancy is somehow a hurdle? It's a choice at least in the modern world. Rape has something to do with people ability to enter an engineering competition? With their ability to get an education?
What institutional level racism or discrimination would a person of color have to deal with that a white male from appalachia would not have? The "justice" system comes to mind but not a lot else. Comparatively they have a lot of programs in their favor.
Sorry your just a SJW with your check your privilege this or that. I'll give you a hint to check privilege in effect means to pull somebody down from there perceived unfair advantages, to say they have no right to the circumstances they were born and/or raised with. Want equality thats enabling people to rise as equals, additive vs subtractive. That's also a much harder sell, to say they are free to earn it that yes their parents are responsible for not giving them a specific advantage etc.
No sir I dont like it.
Get pregnant and see. Oops. You can't. I'm shocked, shocked that you are therefore unaware that pregnancy can be an impediment to career advancement.
Leaving aside the obvious retort that many women don't live in the modern world, it's a choice that men never have to make. Go ahead. Tell me about that time you had to delay your career for 9-30 months because your wife wanted to have a family.
Obviously you have never been raped. When you're afraid to leave your home, it's rather hard to get to your local institution of higher learning. When you are sexually coerced by your Chemistry professor, it's somewhat difficult to trust your other teachers. I don't expect you to understand; your tone deafness speaks volumes about your ability to empathize, but you might at least try to research the things you say before you allow your biases to blithely dismiss them.
Obviously you aren't a person of color. Lower pay. Fewer employment opportunities. Fewer educational opportunities. Grading biases. Selection biases.
Well! I guess the biases in Justice system can't really do much!
This is where citations would come in really handy!
*You're. As in "You're just a privileged while male attempting to mansplain his way through why the world owes him his privilege because everyone else also has access to it. They're just too lazy/stupid/{state character defect of your choice here} to claim it."
*Their. For example, "White people like to lecture socially oppressed people on their problems without understanding what those problems are". Pro Tip: people are far less likely to dismiss you as an uneducated dolt when you use proper spelling and grammar.
“The greatest enemy of knowledge is not ignorance, it is the illusion of knowledge.”
-- Stephen Hawking
This comment is my opinion and does not represent an official position of Donald Trump or others I do not work for
The operative word in that is, of course, "may". At other times, it may NOT be assumed that (etc). In other words, you don't know.
So I assume that I don't know, whereas if I see someone who writes "he/ she/ it/ they" then I do know that it's someone who does think that it's a significant point they're making.
Part of the point is that it does take an effort.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
There is, of course, "one", but that's a bit contrived for some uses.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"
Who the fuck are you kidding? All countries in the civilised world have maternity leave for fathers as well as mothers.
Or do you not live in the civilised world? You poor, unprivileged bastard.
Birds are not dinosaur descendants;birds are dinosaurs, for all useful meanings of "birds", "are" and "dinosaurs"