|
OrgoneConclusion
Blue Fish Group



Registered: 04/01/07
Posts: 45,441
Loc: Under the C
|
Wind Turbine constant speed solution?
#14586461 - 06/09/11 04:31 PM (12 years, 11 months ago) |
|
|
1. Wind turbines all have a sweet spot - a wind speed where they get maximum efficiency which drops off fairly quickly above or below the ideal wind speed.
2. Wind power has 8 times the potential energy at twice the speed. Example: a 20mph wind has 8 times the energy of a 10mph wind.
3. Wind turbines optimized for very high winds have excessive drag at low wind speeds and may actually require a motor to get started.
4. Wind turbines optimized for low wind speeds fail to extract the full energy at high wind speeds. Also the higher wind speeds put excessive strain on the mechanics and/or turbine blades.
There are several solutions to high winds in #4. A. Brake the turbine. Total power loss. B. Feather the blades. Partial power loss. C. Turn the turbine out of the wind. Partial to total power loss. D. Use a complicated gear transmission to change the load on the generator.
My potential solution (sorry no diagrams):
1. Build the generator into the turbine.
2. Enclose the blades with a circular shroud, sort of like a large bicycle wheel.
3. Place permanent magnets in the tips of the blade.
4. Place the copper coils in the perimeter of the shroud.
5. Each coil will be movable by a small stepper motor.
6. Figure out the optimum speed for efficiency.
7. At very low speeds the copper coils will be further away from the magnets (tip of the blades) for minimum drag and easy starting.
8. When the turbine exceeds the optimum RPM, the stepper motors will move the copper coils closer to the magnets increasing drag and extracting more power.
9. When the turbine drops below the optimum RPM, the stepper motors will move the copper coils further from the magnets decreasing the load.
Alternate: If the slight movement of the magnets is not enough to dampen the turbine speed, stronger secondary coils could be brought into play.
Note, I have no experience with wind turbines or generators, although I do have a good mind for finding solutions and an electrical engineering background. Any critique is welcome form those more knowledgeable than I in this field.
--------------------
|
argg
Stranger


Registered: 07/20/09
Posts: 4,848
Loc: Nigeria
Last seen: 12 years, 11 months
|
|
Quote:
D. Use a complicated gear transmission to change the load on the generator.
maybe see how a comet style drive would work. They use them on snowmobiles and big go carts. I think it might not work as is but maybe could be modified to work.
--------------------
|
OrgoneConclusion
Blue Fish Group



Registered: 04/01/07
Posts: 45,441
Loc: Under the C
|
Re: Wind Turbine constant speed solution? [Re: argg]
#14586532 - 06/09/11 04:47 PM (12 years, 11 months ago) |
|
|
I may be wrong here, but I believe these have torque limitations, but that is not the main issue with any transmission system esel they would be widely used on large turbines instead of braking systems.
If the turbine is geared down mechanically, then the generator RPMS go up as does the voltage. Voltage generated past the charging voltage of the batteries is mostly wasted. What we really want to do is increase the amperage while keeping the generator speed within a certain range.
Again, I am not stating facts with certainty, but with my current understanding.
--------------------
|
argg
Stranger


Registered: 07/20/09
Posts: 4,848
Loc: Nigeria
Last seen: 12 years, 11 months
|
|
they do have limitations but custom made larger and stronger to get past the ones in production.
What about planetary gears putting the motion at the head of it into really fast rpms then transfer it down to the ground in a system that get a big ass flywheel going with maybe a couple more flywheels that couple be engaged as needed sort of like brakes you could recover the energy from.
Whether energy transfer via driven shaft or fluids but it could work just have to see how much is lost in transfer. If its fluid driven you could keep having it turn more generators as the wind picks up.
--------------------
|
OrgoneConclusion
Blue Fish Group



Registered: 04/01/07
Posts: 45,441
Loc: Under the C
|
Re: Wind Turbine constant speed solution? [Re: argg]
#14586687 - 06/09/11 05:19 PM (12 years, 11 months ago) |
|
|
Here is the deal: I am sure that the megawatt windfarms have thought of all of the traditional mechanical methods as you suggest, but they opt for the ones I listed - hence a new approach.
BTW, the blade mass is all the flywheel you need.
--------------------
|
Seuss
Error: divide byzero



Registered: 04/27/01
Posts: 23,480
Loc: Caribbean
Last seen: 3 months, 8 days
|
|
Why bother with a mechanical solution when you can accomplish the same thing (assuming I am reading your description correct) with an electrical solution? It is not difficult to create a circuit that alters the impedance seen by the generator. By changing the load that the coils see, you can change the operating characteristics of the turbine. A quick search on "maximum power point tracker" should get you headed in the correct direction.
If you insist on a mechanical solution, it may be easier to use an axial coil/magnet configuration and alter the gap distance between the two plates (one plate has magnets attached to rotor while the other plate has magnets and is fixed) rather than the radial system you describe.
-------------------- Just another spore in the wind.
|
OrgoneConclusion
Blue Fish Group



Registered: 04/01/07
Posts: 45,441
Loc: Under the C
|
Re: Wind Turbine constant speed solution? [Re: Seuss]
#14587021 - 06/09/11 06:33 PM (12 years, 11 months ago) |
|
|
I am not wedded to any specific solution, I just think that braking and feathering seem wasteful of the most energetic winds. I will do some more reading on varying the induction load as you suggest. Seems there must be some drawback though as I highly doubt I am the first the think of such a thing.
Again, axial or vertical, shifting the gap is the same principle, although much simpler in the axial configuration as only one stepper motor (or other actuator) is required instead of several. Very good point!
--------------------
Edited by OrgoneConclusion (06/12/11 04:04 PM)
|
dummy
I am you and what I see is me


Registered: 09/29/08
Posts: 3,973
Last seen: 2 years, 1 day
|
|
are wind turbines only for dc production?
-------------------- People never seem to know what they least suspect is coming next.
|
DieCommie

Registered: 12/11/03
Posts: 29,258
|
Re: Wind Turbine constant speed solution? [Re: dummy]
#14599057 - 06/12/11 01:18 AM (12 years, 11 months ago) |
|
|
Quote:
dummy said: are wind turbines only for dc production?
No
|
OrgoneConclusion
Blue Fish Group



Registered: 04/01/07
Posts: 45,441
Loc: Under the C
|
Re: Wind Turbine constant speed solution? [Re: DieCommie]
#14601769 - 06/12/11 04:04 PM (12 years, 11 months ago) |
|
|
Some turbines swing both ways.
--------------------
|
dummy
I am you and what I see is me


Registered: 09/29/08
Posts: 3,973
Last seen: 2 years, 1 day
|
|
so that probably means they're synchronous and need a starter motor. seems like a lot of trouble..
-------------------- People never seem to know what they least suspect is coming next.
|
dummy
I am you and what I see is me


Registered: 09/29/08
Posts: 3,973
Last seen: 2 years, 1 day
|
Re: Wind Turbine constant speed solution? [Re: dummy]
#14607244 - 06/13/11 04:17 PM (12 years, 11 months ago) |
|
|
or perhaps they're just limited to synchronous speed... which makes more sense than having to start a wind turbine.
-------------------- People never seem to know what they least suspect is coming next.
|
snoot
look alive ∞




Registered: 01/30/05
Posts: 9,644
Loc: 45º parallel
Last seen: 20 hours, 18 minutes
|
Re: Wind Turbine constant speed solution? [Re: dummy]
#14608270 - 06/13/11 07:26 PM (12 years, 11 months ago) |
|
|
mobile wind turbines?
we need like some kind of solar/wind/wave plants floating about in the ocean doing their thing, so when the world ends I can take refuge and eat tainted tuna, and play nintendo.
--------------------
∞ I am incapable of conceiving infinity, and yet I do not accept finity. - Simone de Beauvoir -
Edited by snoot (06/13/11 07:27 PM)
|
|