Google Offers a Million Bucks For a Better Inverter

True, if the input voltage is 240 Vdc and want 240 Vrms out, you have

With sufficient filtering (10-20 ms input filter energy storage) this is within the 8 A average value.

Please note that in this specification the input voltage is 400 Vdc, not 240 Vdc.

Note also that 400 Vdc input voltage is due to the internal resistance of the power source:

Since the average input current is 5 A from the 400 Vdc supply goes either from one of these branches:

• from top left switch to load to right lower switch or
• from top right switch to load to left lower switch

With two 2 V drops in each branch, the saturated dissipation is

With say 50 % of dead time in each branch, the peak current needs to be doubled to transfer the same charge to the filter, but this would make a lot sense with bipolars, with Vce(sat) only slightly increase with doubling the current.

tly and

It certainly does. I ran into this all the time when people were pushing CFLs, using bulb life as a cost advantage to overcome the initial outlay. I blow *maybe* one incandescent bulb a year (I have one in the garage that does it) because I do shut off lights when we're watching TV and when I leave the room and usually have none on in the room to begin with. None are on more than an hour a day.

It would require UL & NEC approval.

and FCC. See new thread: "Million Dollar Universal Outlet"

On a sunny day (Thu, 31 Jul 2014 07:20:17 -0700 (PDT)) it happened snipped-for-privacy@gmail.com wrote in :

Not my server here.

No, that is part of the employee participation program. In these hard times with Aids, Obama, and Ebola, things are tuff. Staff should show their willingness by participating in the EPP and to show that you are no anti-social life form, open the hood of your car in the morning. In the afternoon and coffee break you will run the car's engine to keep power for the company. The newly formed technical department will connect all the cars with open hoods. The guys who refuse to open the hood will not receive the Christmas gift frozen rabbit,

That doesn't make sense. Double to 300s and back down to 12, 5, 3.3, 1.8, 1.2, 1.0, 0.8, etc? Most laptop chargers auto detect 120V or 240V.

That's very expensive electricity, in terms of oil/gas cost and pollutions.

On a sunny day (Thu, 31 Jul 2014 11:09:15 -0700 (PDT)) it happened snipped-for-privacy@gmail.com wrote in :

We are not talking about laptops, but big PC power supplies.

It makes a LOT of sense. Look up the circuit diagram of a PC power supply

google

At least in Europe, the power levels have significant impact on circuit construction. For power levels above 75 W, some kind of power factor correction is needed with very large input voltage range (rectified, but not smoothed mains waveform), Thus, this should be able to handle both 120 Vrms and 230 Vrms without circuit switching.

For small supplies without PFC, the switching between 120 V doubler and 230 V full wave can make a lot of sense in some cases.

With a huge number of small electronics loads such as CFL and LED lamps and various charger, my guess that the PFC requirement power level from 75 W will drop to much lower ratings, say 5 W within a few years.

For DC/DC or DC/AC converters, of course no PFC is needed.

Regarding equipment designed for DC operations, I have seen a lot of industrial devices designed for up to 8-30 Vdc input range, suitable for both "12 Vdc" and "24 Vdc" environment and most even accept similar ranges for AC as well, without modifications.

While incandescent lamps are sensitive to 1-2 % voltage variation, causing annoying flicker, which requires keeping feeder (line) resistance low during variable load conditions, most electronic power converters will allow large input voltage variations, while still maintaining stable voltage to each customer (brownout compensation).

While keeping the maximum current below the conductor thermal limit, you can use longer conductors (e.g. substation to home) when

can be high during peak hour, most of the day, the losses will be much smaller.

On a sunny day (Fri, 01 Aug 2014 11:08:02 +0300) it happened snipped-for-privacy@downunder.com wrote in :

I keep thinking good old 3 phase (6 diode rectifier) gives about 5% ripple IIRC even without capacitors. Then you only need the caps as RF decoupling for the switcher regulator after that.

Yes, absolutely, 24V is a common standard, 24V industrial PC you can just buy in many places. I have not seen a 12V but that would be no technical problem, been out of that stuff for many years.

It would be nice to have some RTGs, cooled with water from a river for example.. years and years of energy.... And constant. Not enough plutonium yet...

It stopped workin last night, then I decided to fix it, cleaned table, got scope, diagrams, and switched it on and it worked, all by itself. Not sure about cabriotilation though. What happend? Close by supernova? Note the huge pulses at the right end of the scale. Cosmic end of the universe? Good I have a spare PMT.

Ah, Fukushima... hehe

I have also been playing with the idea of using RTGs to building heating using something like Apollo era SNAP RTG generators, which would be barely usable for keeping your swimming pool warm and function as an UPS for smart phones :-).

Unfortunately the power output is a bit too low for general purpose applications without hugh amounts of very active (short half life materials).

A more realistic option would be some TRIGA style real nuclear reactors with thermal power in the 100 kWth to 10 MWth power range. This might be sufficient for heating and providing electricity for a small suburban area.

Yes, 4.2 % rms ripple, of course, the peak to peak ripple is a few times larger.

In Europe, three phase feed is available to most apartments, but not in every room socket.

On a sunny day (Fri, 01 Aug 2014 15:45:15 +0300) it happened snipped-for-privacy@downunder.com wrote in :

Oh, I agree with that, always have been in favor of nuculear . And not only for power, for spacecraft too. NASA once had a design for a nuclear powered rocket (no not that push plate bang bang thing). But people are now so scared of the word 'nuclear' that they even removed the 'N' from NMRI In Germany after fuckupshima all nuclear plants are being shut down, including the new ones under construction. And there is of course the fear of 'proliferation', complete bullshit too. If I wanted to mass murder a country or city I would just put some ebola infected meat in a rocket, or in the mail for that matter, mice would eat it, cats would eat mice, birds, owls, people, no more over-population. Anyways looks like that will happen anyways because of doctors being send there that then will travel the world and infect everybody.

So, all that fear... let's go critical. It was a slogan from the eighties "let's go digital", even a song I think. So let's go critical. :-)

You know, in the US, where they cannot even kill somebody, let somebody sentenced to death suffer for hours, that same country that is the biggest exporter of arms in the world, does not know how to shoot somebody in the head. Society is REALLY **completely** schizo, its one half (old women, fat man) does not know its other half. So nuclear... Anyways I think the pioneer spacecraft has several hundred Watt from RTG, still, 275 W remaining? I would like one like that. Maybe somebody can build a private space-thing and pluck it out of the sky..

Should I REALLY put a smiley here????

OK for those who need it now: ;-)

Let's get critical.. critical.

--sp

Note the availability of 120vDC ATX computah power supplies.

There are also internal 12vDC to ATX connector power supplies for the smaller machines (ITX, mini-ITX, etc): I've a few of these for DC only weather stations and automobile computahs. Ferrite beads needed to keep them quiet.

What's nice is that every technology has its own DC standard:

Standards are such a good thing that everyone should have one.

On a sunny day (Fri, 01 Aug 2014 07:37:19 -0700) it happened Jeff Liebermann wrote in :

Expensive...

Yes, sure.

Amazing.

My telco modem had an AC wallwart, so my V90 modem.

There is an amateur co-channeling experiment that works really well where I am on 70 cm.

Yes, I make my own all the time .

IME, those things can be somewhat unreliable. You're better off getting a single voltage MB. Some motherboards are now rated for 8-32VDC input in various form factors.

That must be the thermal power for Pioneers.

Apart from simplicity, I do not understand why NASA is using RTGs for their planetary missions. If you have a bad launch failure, quite a lot of short half time and hence very active radioactive material is spread into the environment.

However, if a real fission reactor explodes at launch, the enriched uranium is not that big deal. After successfully escaping from Earth orbit, activate the reactor. Only then it will going to create nasty short lived isotopes.

Don't activate reactors on Earth orbit, as it will sooner or later fall to the Earth, as in ther case of Soviet Kosmos radar satellite that fell into Canada a few decades ago.

On a sunny day (Fri, 01 Aug 2014 18:52:06 +0300) it happened snipped-for-privacy@downunder.com wrote in :

I think those RTGs are crash proof as far as Pluto Nium is concerned?

I am not suee, but I think Cassini uses nuke power too,

and the recent Chinese moonlander the same.

You can be Ferry Sure US as well as Russia have or have had reactors in orbit.

Yes right.

It is not a big deal if it lands in the ocean in one piece, the bottom is littered with sunken nuclear subs :-)

And it all radiates anyway due to fuckupshima.