A new kind of wind turbine gearbox?

[Windward]

Here are some claims for this new gearbox:

"Our box will last five to seven times longer than the traditional design," said Attia, who said a traditional gearbox costs upwards of $200,000 per wind turbine, but only lasts two to three years.

"The gearbox Ivankovic and Attia have developed will be priced similarly, Attia said."

http://www.news-journalonline.com/article/20130512/BUSINESS/305109958

Sounds too good to be real, but one of the inventors has some good credentials. I can't find any design details for this gearbox. If anyone knows what they are, please post.

 

[tbuelna]

It looks like some type of oscillating cam/roller mechanism. I've seen similar devices, but they never perform as advertised. A good quality modern epicyclic wind turbine gearbox will last far longer than 2-3 years as claimed. One problem with these cam/roller drives is that they tend to have lower efficiency than a conventional gearbox. And this is a big problem for a commercial wind turbine drivetrain.

 

[Windward]

Looks like you were right, tbuelna:

"Components are cams, pins, discs, rollers and a cylindrical housing…"

http://www.abmengr.com/#!/2568/qdrive-gearbox-innovation

The publicity about this device reminds me of the Universal Transmission, or Moon Gear:

http://vmt-news.blogspot.com/

Maybe these outfits have something, maybe not. I know that it takes a lot of time, money and testing to prove a new gearbox idea, especially whether it is good enough for a wind turbine, so I am willing to give them the benefit of the doubt for now.

 

[Pud]

Might be a bit late to market:

No Gearbox Wind Turbines

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[Windward]

Pud, a direct drive wind turbine may be as good as a geared drive up to about 1 MW. Above that, I believe that DD is folly. You can find some reasons for that at

thread406-367399

Regarding the often-heard claim that DD is more reliable because there are fewer moving parts, see Werner von Braun's response in that thread and some discussion of it.

Objections to DD:

1. Cannot eliminate the power electronics. This requires a geared turbine such as the Dewind 8.2 and 9.2.

2. Requires rare earth magnets to keep the generator size and weight down to the barely feasible. Uncertain supply and high cost of rare earths are serious disadvantages.

3. Does not allow a vertical drive shaft. This also requires a geared turbine. See the thread listed above.

4. Does not reduce tower top weight.

5. While superconducting technology would reduce the size and weight of a DD generator, I doubt that the cost would justify any benefit.

 

[Pud]

Windward: Not my field at all - just happened to have read about. Someone at least (GE) thinks it's worth pursuing though, as they are going to spend €340 million on it.

Cheers

H

www.tynevalleyplastics.co.uk

It's ok to soar like an eagle, but weasels don't get sucked into jet engines.

 

[tbuelna]

Pud-

Trust me, there is no way GE would spend close to $500M of their own money to bring a DD commercial wind turbine to market. GE dominates the US commercial wind turbine market because they own IP for the standard DFIG design used for 95% of the US market. Globally, over 80% of the market is still for DFIG turbines using gearboxes.

 

[gearcutter]

Looks like DD is alive and well 'down-under'.

http://www.sciencealert.com/new-sup...nes-could-hit-australian-shores-in-five-years

 

[tbuelna]

gearcutter- I glanced over the article you linked, but the claims made by that company regarding the cost and efficiency of their superconducting generator are nonsense. Seriously, "1000 times more efficient and 1/3 the cost of anything on the market"? A conventional utility scale DFIG and gearbox turbine design is about 85-90% efficient at converting rotor shaft power to grid-ready electrical power. As for cost, the typical price/kW for a utility scale turbine is under $1000. And more important is the fact that this superconducting generator likely requires a complex system of cryogenic cooling.

 

[gearcutter]

tbuelna - I agree, it does sound too good to be true.
The team isn't a company or organisation, they're part of the Institute for Superconducting and Electronic Materials at the University of Wollongong, NSW.

 

[tbuelna]

I'd like to think something being promoted by a group affiliated with a public university would be more careful about their claims. A private sector company making similar unusual claims about a technology they are developing for the commercial market, and which may have an effect on the company's financial performance and value to shareholders, would be facing serious consequences if the claims turned out to be exaggerated.

 

[Windward]

I'm with tbuelna and gearcutter about that outfit in Australia. If we read the article as comedy, I like this statement:

"This, and the fact that the copper wire decays quickly, means our current power systems are relatively inefficient with short lifespans."

I would like to know what others think of another proposed wind turbine drive train:

http://www.engineering.com/Electron...eID/6466/Shifting-Gears-on-Wind-Turbines.aspx

"The technology uses a transmission of sorts, but instead of mechanical gears, belts, or chains, the ZCT uses neodymium permanent magnets to make the generator in the turbine spin five times faster than the rotor."

I know just a little about magnetic drives. For instance, units like the one described at

http://www.engineerlive.com/content/magnets-offer-alternative-mechanical-gears

may lose timing for a short while when speeding up or slowing down. That is, the output may not directly follow the input according to the gear ratio for a little while. Maybe only under heavy load. I can't remember where I read that. Maybe this would not be a disadvantage in the typical variable speed wind turbine, where the AC is wild anyway before conditioning by the power electronics.

 

[Windward]

More on magnetic gears:

http://www.spacedaily.com/reports/Researchers_develop_a_magnetic_levitating_gear_999.html

"Levitating" means that it has magnetic bearings.

Are any other of us gearheads getting nervous yet?

 

[jdunfee12]

Here are a few quotes from the thread, "Sounds too good to be real," and "I'd like to think something being promoted by a group affiliated with a public university would be more careful about their claims".

Those sound like appropriate things to say any time alternative energy is considered... especially wind energy.

-Joe

 

[tbuelna]

joe- That's a fair point, but we should also remember that universities rely on research grants to fund most of the work done by their engineering and science post grads. I have no problem if they framed the research effort as being an attempt to demonstrate that a proposed technology might have some potential for improving the current SOA of a well-developed existing commercial product by something like 10%. But no self-respecting engineer or scientist would make the type of claims these people made.