| T O P I C R E V I E W |
| Mertz |
Posted - 14/04/2008 : 15:58:47
I hooked up the voltage booster over the weekend and am now reading 13 plus volts on my Ametek even in light wind. The input voltage at 2.77 has an output voltage reading 13. I have is set so that it will go up to 13.20 with the batteries connected. The Indiana is producing about 7.8 while the Ametek is at 13.20 in higher winds. In theory I am inputing the 13 volts from the Ametek and the amperage from the Indiana to the batteries.
I am very please with the results. Next step grid tie inverter.
Mertz |
| 15 L A T E S T R E P L I E S (Newest First) |
| s4w2099 |
Posted - 05/05/2008 : 01:58:22
Hello guys, this is my implementation of Flux's idea for a boost converter for windmills. This one does as he explains in his diaries. It has a potentiometer to set the cutin speed and has another one to set the output current limit while under boost.
I made this one small it can only deliver about 125Watts max when used at 24V. It works great for two system voltages, 12 and 24V. The output diode can handle up to 16A continuous MAX so after boost this is the current limit that it can handle.
For full explanation of how this device works please visit:
http://s4wsbox.com/?q=node/32
http://s4wsbox.com/shop/boostlabel_small.jpg
Note, this will not collect power if it is not already available in the wind, no magic here. The power curve from this booster should always be below the propeller power curve to avoid stall.
If anyone is interested in one of this boards please contact me. Ill order the parts and put it together. I will ship only to USA, Canada and UK.
Schematics are free for personal and educational purposes. In case anyone decides to put it together here they are in this link: http://s4wsbox.com/shop/windBoostSch.png
email: movlw0x13h [at] yahoo [dot] com
arrrrg! dont have a clue how to include a picture inline. Just click the generated link to see a picture of it. |
| ghurd |
Posted - 21/04/2008 : 22:48:19
You may confusing terms.
Watts is Watts is Watts.
A taser runs from 3V or 6V or 9V, but would cook before getting a 12V battery to 13V.
A taser run from a 24V battery would smoke before getting a 12V battery to 13V.
My wife went to school with the "taser warren" cop. LOL.
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| larrylawrencejr |
Posted - 21/04/2008 : 22:33:25
quote:
Originally posted by gotwind
That's a nice little voltage booster.
89% efficiency sounds good.
Would be great for the dynohubs or Ameteks in low wind areas.
Ghurds opinion would be useful.
and its availability in the U.K also
Ben.
What would be the largest safest amount of voltage that one could convert and then dump back into a 12 volt battery bank?
Is it safe to take 12 volts and boost it to 24 volts, then dump it back into the battery bank? |
| s4w2099 |
Posted - 17/04/2008 : 04:54:12
LOL that pretty funny. 
I plan to have kits available for sale of this device as soon as possible but the schematics will be free for all if you want to build it yourself.
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| ghurd |
Posted - 16/04/2008 : 21:51:46
Ghurd help s4w2099? I don't think that's a great idea.
I see 3 outcomes...
#1 He steals all ghurd's great ideas, patents them, makes a gazzillion USD, and twice as many GBP, and has Bill Gates cleaning his washroom for extra money.
#2 Ghurd has no idea what that young, still wet behind the ears, whipper-snapper is talking about, because ghurd hasn't really delt in depth with these theories in 25 years, let alone the related new chips.
#3 Ghurd's ideas make so much TO-220 smoke it starts the next mini ice age, TTU kicks s4w2099 out of school, he works at McDonalds for the rest of his life instead of designing the new twist on wind power.
Sorry. Finished my income tax. Still don't have my head together. Bit of a goofy mood. 
s4w2099,
I remember you. If I can help, please ask. (see #2)
And Good luck with exams and the circuit,
G- |
| gotwind |
Posted - 16/04/2008 : 21:45:43
Interesting points all around.
I suspect the whole solution is a bit of a compromise.
Ultimatly good wind yields power, nothing below 6 mph will generate power apparently.
I'm happy to look at proven electronic circuits (e.g Ghurds charge controler)to sell on gotwind,with permission obviously, complete units or self built.
I'm working on an online gotwind shop at the moment, good for all I hope.
Ben.
The Futures Green - Getwind of it. |
| Mertz |
Posted - 16/04/2008 : 20:49:40
Just so you know I have not stalled the Ametek yet. I have noticed it slow down in some very high winds which I think could be an advantage. There have been no slow downs in the 13 mph winds of this week.
The booster has been running since Friday afternoon under some above normal winds and I haven't had any problems with it yet. Lots of good points made here that are way over my head electronically.
The new booster sounds like a very good option. Do you think you will be building them and selling them to your friends here at gotwind to earn some extra college money? I know I won't be able to build one myself. Maybe Ghurd could help with the project.
Mertz |
| s4w2099 |
Posted - 16/04/2008 : 17:07:28
Hi guys I am new here. I am an Electrical Engineering student at Texas Tech University and power electronics is the thing I like the most.
Ive been developing a boost converter for a while now. It is specifically designed to be used with windmills. The problem with a regular boost converter is that it has a voltage feedback loop. The boost converter will increase the PWM until its output reaches the output voltage that it was programmed to. This is bad for windmills as it will stall the blades.
The version that I am working on does not have a voltage feedback loop so it will not stall your propeller. The feedback is taken from a hall effect current sensor. As the output current grows the PWM is phased back allowing the propeller to speed up and reach cut-in by its own. Thus the boost converter automatically turns off in higher winds.
The current at which the boost converter will shut down can be set with a potentiometer. Also there is another potentiometer that is used to select the voltage that it is going to boost from.
This combination of features will enable you to recover some of that energy available in low winds (when the mill can not reach cut-in).
I have schematics for a regular boost converter (not for windmill) that you can grab on my website for free. If you are electronically inclined you can put it together and eliminate the voltage feedback loop and replace it with a hall effect current sensor.
I have already made the schematics and a first prototype of this device and it is being tested as I write. I thought that I was going to have concrete results by last weekend but teachers decided to give exams this week. 
http://www.s4wsbox.com/?q=node/26
Thats the link to the schematics if you all want to build a standard boost converter.
Ill have you all posted on how it turned out, so far its working great though. |
| Tim L |
Posted - 16/04/2008 : 16:26:29
Ah, OK, thanks Ghurd. Frequency didn't occur to me at first, dunno why not!
Note: A YouTube Video Is Not Necessarily Proof Of Anything At All
www.youtube.com/watch?v=UpNp4l0qyY0 |
| ghurd |
Posted - 16/04/2008 : 16:24:55
Cockcroft-Walton, and all cap and diode voltage doubler schemes, only work with AC.
The capacitors need to be HUGE to get many watts out, because we are working with low frequency. They should probably be "current rated" too.
The cost of the capacitors may be greater than buying a better suited alternator.
G- |
| Tim L |
Posted - 16/04/2008 : 16:14:50
For normal wind turbines, am wondering what the advantage is of these units over a simple 3 phase cockcroft-walton voltage multiplier?
http://www.reuk.co.uk/Three-Phase-Voltage-Multiplier.htm
Of course it's no good for DC to DC applications.
Note: A YouTube Video Is Not Necessarily Proof Of Anything At All
www.youtube.com/watch?v=UpNp4l0qyY0 |
| ghurd |
Posted - 16/04/2008 : 15:23:55
For brushed DC generators, I never had any luck with small ones. Never really heard of any luck with larger ones.
They are based on theroies I have not used in 25 years.
I know a guy who has been working on them for a few years. He may have given up on the idea.
My understanding of his results...
They are designed to have a stabile supply voltage, and as soon as curernt is removed from a windmill, the voltage drops.
They are designed to instantly supply the full output voltage, and they can't do that into a battery.
They keep trying to do there job, but the efficiency sufferers greatly (like under 50%, maybe under 10%).
The harder they try, the more stress on the parts, and failures of parts happen quickly.
Pulling current from a 12V windmill while it is making 6V can (will?) keep the windmill in stall, greatly reducing the chance it can reach 12V, and reducing the efficiency to a small fraction of what it should be.
When the battery reaches the output voltage of the boost converter, it reduces the amps to the battery (and from the windmill).
The windmill is running unloaded, speeds up, passes 14V rated input of the converter, and the converter blows up. Might be a simple way to bypass that.
It is easier with single or 3 phase AC, but still quite a nightmare to get the timing correct. Timing being when it changes from voltage amplification to direct feed.
Single phase AC can be done with a transformer, and some other parts. I'm told it creates considerable extra cause drag at low RPMs (low HZ), but I don't have a way to measure it.
3 phase can be a star-delta switch, and some people have had good luck with those, though it is still not really a DIY project for anyone who doesn't already know how to do it. The parts need to be sized to the specific windmill.
I never tried it, because if the lesser winds blow before the higher winds, my little batteries are nearly full anyway, and the big winds top them off. Meaning by the time the wind is strong enough to use the extra efficiency of delta, I don't need it.
Not trying to be negative. It seems like if someone had good luck with things like that, we would know about it by now. Or one of the big manufactures would add it into the windmill.
Not sure if any of that helps, but it sure used up some space!
G-
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| gotwind |
Posted - 16/04/2008 : 11:16:27
That's a nice little voltage booster.
89% efficiency sounds good.
Would be great for the dynohubs or Ameteks in low wind areas.
Ghurds opinion would be useful.
and its availability in the U.K also
Ben. |
| Mertz |
Posted - 15/04/2008 : 01:50:14
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Mertz |
| super windy |
Posted - 14/04/2008 : 23:15:16
Yes please mertz, maybe we have the same product here in the u.k and don't know it.
cheers super windy
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