raser

[jag27]

i recently came across a new type of technology for motor manufacturing called raser
they claim to have far better performance than conventional ac motors. any one has any idea how this thing is supposed to work?

how can a wound rotor induction motor generate more power than a PM motor

 

[UKpete]

I haven't had a chance to go through their website in detail but my first impression is that it is power-marketing. By comparing with another motor type of their choice, it is possible to make their own technology look superior.

I do not believe that any other type of excitation can improve on PM performance in terms of power density and conversion efficiency.

 

[electricpete]

I had an opportunity to tour a research lab at a large motor manufacturer maybe two years ago. The folks there were really excited about reluctance motors with some kind of electronic drives. I must be getting old because I can't remember any more details but those guys seemed pretty confident that reluctance motors were going to replace squirrel cage motors in most new industrial applications within a decade or so.

Take it with a grain of salt, but that's the way I remember it.

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[electricpete]

I'll bookmark this thread and come back in 2013 to see if it came true ;-)

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[electricpete]

I took a quick look at the site and as far as I can tell it from the very few specifics they mention it doesn't look like they are offering anything revolutionary. Many vfd systems certainly can claim a significant efficiency improvement accross a wide range of existing fixed speed applications.

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[Skogsgurra]

I had a look too. I was looking for tell-tales revealing revolutionary technology. The motor is hard to say anything about but the controller seems to be a school project in a professional box.

I do not see any attempt to reduce internal inductance, there are cables and copper bars with ample of air in-between.

I do not see anything that could reduce EMI - and that is typical of school projects.

I do not see any attempt to reduce size. There is a lot of air in the box. Also typical of a school project.

The box is supposed to be fed with DC, probably from a (300-400 V) car battery. There is no rectifier and there are no large capacitors inside. So a comparison shall not be made between a mains powered inverter and this inverter.

It is also interesting to see that some of the comparison graphs are based on computer generated data. Based on what input?

A peak output of 180 kW is impressive. But for what period of time? Is it an equivalent to the famous "peak music power" of audio amplifiers? That used to be about four times DIN power - if I remember right.

But the office looks impressive and the picture from the lab has "the right look" - except that it is a little "too right" with characters that look like they were hired from a model agency.

I will also book-mark this site. And come back to it now and then. But I will not buy stocks.

 

[don01]

oh yee of little faith!!!
now my grandad dint think that new fangled eltrizinty stuff could amount to much. you know pushing smoke thru wires how's that gonna cure any ills.

but then again I dont think I'll buy shares either

(ps it's obviously smoke cause every time you break the wire theres a heap of "sparkin an smoke")

Don

 

[Skogsgurra]

Your spelling, Don!

That aside (I did get it) a manufacturer that wants to be credible in his claims has to present more facts than what can be read on the home page of Raser.

And I do not think that this qoute from the unknown Jack Kerlin makes things much clearer. (Jack is an engineer or scientist that works with Raser):

"Raser has advanced motor technology closer to the theoretical limits set by the Laws of Physics."
–Jack Kerlin, Physicist, Electromagnetic theorist.


It is not about "little faith". It is about seeing relevant facts. And when I see what I need to see - I will also believe. But only then.