Switch Circuit Drive

[Takhinen]

Hi !
What is the difference between PWM inverter and Switch circuit(SC) inverter ?
Where can i find information about switch circuit(SC) patent and its possibility to be used in VSD?
Seems to be that switch circuit inverter is more progressive than that one uses PWM , but how to form output signals from inverter with SC to make them sinusoidals( voltage & current) ?
Thanks in advance

 

[Skogsgurra]

Hello!

The only inverter that does that is the NFO. Go to

http://www.nfodrives.se.

Click the British flag. And then "Read more" about half-way down the page.

I actually did some of the writing (sorry folks, can't help).

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[Takhinen]

Thanks Gunnar !
yes , i went to the link

http://www.nfodrives.se/

and red about the patents.I hope to find more therotical information whith details about max power rating of the Switch Circuit Inverter (SWI)and the way or modulation to form the output sinusoidal signals ( voltage & current).
In my opinion if we can get sinusoidal outputs from the inverter as mentioned on the home page of NFO Drives ,then such inverter will replace the PWM one, and has promising future in accurate drive systems unless there is unknown limitations .
I hope collegues will come with more information about SWI .

 

[Skogsgurra]

Hi,

The limitation up to now is that MOSFETs have been used in these inverters. And that limits output power to around 15 kW.

There are two new patents that both make IGBTs possible. That would increase the possible power rating to that of standard inverters - hundreds of kW. Especially the multi-phase patent is very interesting. There is a US patent number. I shall look for it.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[Irrelevant]

Hello Gunnar, how do you think the new EMC directive will impact on the drives industry the coming years? from what I understand you won't be allowed to sell drives that don't comply with the directive after 2009-07-20. It seems like they finally might be in the sweet spot for license takers and OEM customers and that directive might be what they need. In my opinion the IGBT application and some OEM customers will be crucial for their future. I would appreciate some of your opinions on this matter.

 

[Skogsgurra]

Hi, these fora are mostly for technical discussions and tips. Your question, although it has some technical interest, seems to be more of a shareholder's question. So I don't think it fits in here. But it is surely interesting.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[cswilson]

Skogs,

Is Natural Field Orientation from the work of Ragnar Joensson? I met him in the late 80s when he was in the US presenting the concept. I still have some of his papers in conference proceedings.

Do you have references or patent numbers on these technologies?

Thanks!

 

[Skogsgurra]

Yes Curt! I talked to him as recently as last week. He has a new patent registered where he can use IGBT:s and reach high power levels.

The patent number is US 6,940,736 B2

The prospect of seeing high-efficiency, EMI free and EDM free, sine-waves for induction motors is exciting.

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[waross]

Gunnar and Curt; The concept does sound exciting.
I am sure that many here as well as myself would like to hear more.
Can you give us a simple description of the way in which SCI technology differs from PWM.
The first sentence says it better.

Hi !
What is the difference between PWM inverter and Switch circuit(SC) inverter ?

A collective thanks from all of us.
Respectfully
Bill

 

[itsmoked]

Ditto!

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[cswilson]

It's probably best to look at the patent descriptions themselves, with figures. You can download from the Patent Office website for $3.00

 

[itsmoked]

Yes no doubt!

But no one can summarize with a few sentences?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[Skogsgurra]

I once wrote something called "The One Stop Solution". It is not a "few sentences" but more like "several pages". I just can't figure out how to make it avaiable. Keith? You always have solutions. Is there somewhere I can put it?

Gunnar Englund

http://www.gke.org

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100 % recycled posting: Electrons, ideas, finger-tips have been used over and over again...

 

[itsmoked]

Gads! How many ways are there to switch an IGBT?!?

If you send it to me Gunnar I will figure out how to put it up.

Hey you could jam it into a FAQ maybe.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com