Efficient Power Conversion (EPC)

GaN Systems

Transphorm

Panasonic

Infineon

Disclaimer: I work for one of the listed companies. We welcome new members to the GaN club!

I apologize to the ones that I missed.

You are wrong, in my opunion.

I meant "you're", not "your".

I work at GE too. How's their stock doing? Enough said.

I am a technical contributor for a large corporation. I don't program, unless you count MATLAB/Octave/Scilab as programming. Over the years, I have come to avoid spreadsheets and word processors in favor of simple Latex editors and Octave. It's not because I like them, or I like the command line, or that I like the control they give me. I find that they are a pain really. So why do I do it? Why?

Word still stinks, and Excel is no good beyond making a 2-d graph of one variable versus another. Sure, they can do more. The problem is, I don't sit at my desk all day. I go to the lab and try things out. Sometimes, I don't revisit an analysis for 6 months, or even 5 years. After a year or so, a complex spreadsheet is no good, if you can't remember the details. Octave code is much easier to go back and figure out what I did, and MUCH easier to comment.

Don't get me started on Word. It still cannot handle figures, graphics, and equations in a simple, consistent and bug-free manner. I don't feel a thrill using latex, and it has enough of its own problems. The thing is, once I solve a problem in Latex, it stays solved. Not so with Word. Enough said.

Here is the issue. Document generation has largely been solved, and really all that is needed are bug fixes and refinements. This is not profitable enough. This is not my problem, but it is a problem for Microsoft. They don't care about me, they care about their profit.

The sloshing of ions in batteries reflect themselves as a disturbing muddying of the high registers. Capacitors may help, but only if they have graphene concentric plates with vacuum dielectric. The plates must be closer than the Casimir distance to prevent virtual particle pair formation from adding a faint, but clearly perceptible haze.

MIT is a top notch establishment, but that does not mean everything they do is beyond question. Think "Witricity".

Actually, the first plant is being built in the USofA
.

While you are right about the marketing end, you are incorrect in extending the marketing objective's influence into the inception, design, and data collection phase. Sure, they display simplified graphs to the general public in order to sway opinion. Why do they do it? Because the underlying data suggests that there is money to be made. You can bet that there is a lot of underlying data, which was obtained, analyzed, and reported internally at no small cost. GE needs to convince itself first before it tries to convince others.

...that Phoenix was just like LA, but with none of the advantages!

As an engineer with a healthy skepticism of models even on things that are relatively well understood, all I have to say is "No shit, Sherlock!"

John

Not to mention that they would cost a lot more if this were actually true. A little research reveals that shipping costs for a 4-pack of CFLs is much less than $1USD, and more like $0.05 to $0.25. That's pennies per bulb, and fuel costs are a fraction of that amount.

Since I expect to save $20-40 per bulb in electricity, I think that it is unlikely that more fuel is consumed in shipping over the life of the bulb.

John

The electric field strength of dielectrics is a function of material thickness, with thinner materials generally exhibiting a higher field strength. Thus, a thinner dielectric has a higher breakdown field.

A common rule o' thumb is that to double the voltage breakdown of a given sheet of insulator, one needs to multiply the thickness by a factor of 4. The exact exponent used depends on the material type, quality, etc, but the gist of it is that thinner materials can have much higher breakdown strength than one would expect from testing a thicker material.

Many other factors play an important role, such as field strength enhancement due to small radii, voltage rate of change, material defects, humidity, temperature, and so forth.

Finally, there is evidence to suggest that certain concentrations of nanoparticle fillers may increase dielectric strength.

Disclaimer: IANAMS (I am not a material scientist), but I have done some high-voltage design. Dielectrics are still a black art, if you ask me. If you don't believe me, ask a dielectrics expert a quantitative question sometime, and see how long the answer is.

Note the requirement for the charging station.

There are a number of ideas for "charging pads" or "charging mats" with a matrix of planar coils. The power receiver would be in the back of the item to be charged and rest directly on the pad. They are transmitting power via magnetic coupling, but over much shorter distances (mm, not m). This can actually be done with reasonable high efficiency (>90%). Sorry, I don't have the references on the top of my head.

On the other hand, Witricity is a dog because they are trying to transmit power over a distance on the same order of the coil's radius or farther. Without a winding with much better conductivity than copper, this cannot be very efficient (60-75% is pretty poor). The resonance aspect does not affect the coil transfer efficiency in theory, but it helps in practice because power electronics components are, alas, non-ideal.

If you ever have a chance to see someone demo this, ask them to put the coil axes at right angles to each other and see what happens...

John

...they don't even tell the patients that they are getting a placebo!!!