Author Topic: Light Weight Wind Turbine Project - as I build it.  (Read 240550 times)

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Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #66 on: March 26, 2012, 02:10:57 PM »
Well, I saw the light!
I am scrapping my Ametek 40VDC  motor. (selling it back on ebay)   

I just bought a “Hurricane Cat 4 Mark I Low Wind PMA for Wind Generator”
it ran me $260 with shipping...


here is their write up:
This is a 3 phase ac generator....that does not mean you can hook it straight to your grid!

Seems today you have two schools of wind generator sales......the old school where the guys lie tell you the generator output 3000 watts the customer thinks wow and buys. The new school invented by some other companies  where they speak of "real world" output and are the knight in shining armor out to save you from everyone who is trying to cheat you..... and you the customer should be thankful for the wind genie who saved you. We are unrolling a 3rd approach here.
 
1. The best low wind product on the market made completely in the USA no imported copper ,magnets, components....I mean is was all bought and assembled in the USA....a major feet in and of itself trust me

 2. The best price on the market  compare TLG 500 in excess of 600$    by the way we have better output

3 No pressure sales approach....we have no trouble whatsoever selling these and will be here for the long haul... Seems when you have truly built a better mouse trap you don't need  a sales approach  go figure

•   Hand made in the USA
•   Produces power in very light wind
•   Perfect for wind, hydro and marine applications
•   Comes pre-wired with power cord
•   Includes ac-dc rectifier
•   Produces 12 volts at just 80-100 rpm
•   Robust bearings and housing
•   Will last many years in harsh environments
•   No internal parts or brushes to maintain
•   90 Day full replacement warranty
•   80 RPM- 12 v. x .50 amp = 6 watt

100 RPM- 16 v. x 1 amp = 16 watt
200 RPM- 36 v. x 2 amp = 72 watt
300 RPM- 48 v. x 3 amp = 144 watt
400 RPM- 55 v. x 4 amp = 220 watt
500 RPM- 68 v. x 5 amp = 340 watt
600 RPM- 78 v. x 6 amp = 468 watt
700 RPM- 89 v. x 7 amp = 623 watt
800 RPM- 97 v. x 8 amp = 776 watt
900 RPM- 110 v. x 9 amp = 990 watt
1000 RPM- 121 v. x 10 amp = 1210 watt
1100 RPM- 134 v. x 11 amp = 1474 watt 
1200 RPM- 142 v. x 12 amp = 1707 watt
1300 RPM- 159 v. x 13 amp = 2067 watt
1400 RPM- 166 v. x 14 amp = 2324 watt

Hurricane Cat 4 weight approx. 11 pounds. Shaft size 17mm x 2". Comes with rectifier, hub bushings, 17mm nut and lock washer

How did I do folks????
Did I make the right call???
« Last Edit: March 26, 2012, 02:57:28 PM by Steadfast »
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Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #67 on: March 26, 2012, 02:55:19 PM »
I know I switched gears on you guys with this change... But I NEED HELP getting this right...

How is my new "Hurricane Cat 4 Mark I Low Wind PMA" going to Revise my (Below) Wind Turbine Generator Layout?  Regaurding the wire connecting the tubine to my ac-dc rectifier and then to the batteries, will I need different gauge wire than my previous 10guage at 40 feet length?
What other things do I need to know?



Remember, I took this wednes day thru Saturday off from work to knock this out...
Yikes...Help...
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fabricator

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #68 on: March 26, 2012, 04:43:46 PM »
One more time, NO fuses between the batteries and the turbine, anywhere, there will be three wires from that alternator to the supplied rectifier, I'm assuming it's a three phase rectifierprobably something like this file:///C:/Users/Dale/Downloads/100%25%20NEW%20THREE%20PHASE%20RECTIFIER%20BRIDGE%20MODULE%20300AMP%20on%20eBay!.htm, you can erase the 35 amp diode as it's totally unnecessary.
There will be two wires from your batteries to your inverter, for 12 volts you need to go from + on one batt and - on the other, the two open terminals go to the + and - on the inverter, just go over to west marine and get a couple 100 amp terminal fuses and fuse the positive the positive posts.
There will be three wires going on to your rectifier from the alternator and a + and - coming off they go to their respective terminals on the batteries.
I aint skeerd of nuthin.......Holy Crap! What was that!!!!!
11 Miles east of Lake Michigan, Ottawa County, Robinson township, (home of the defacto residential wind ban) Michigan, USA.

birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #69 on: March 26, 2012, 09:36:14 PM »
personally, i'd send that "hurricane cat 4" or whatever rediculous named unit back where it came from. 

it's eleven pounds, and cost you $260...  plus, you can see in their charts how they're testing with shorted amps and open voltage to predict output??  there's nothing "real world" about that!  it'll probably work, but i doubt it will produce anywhere near your expectations.  especially your "$260" expectations.

for a small mill, i don't think the price per output can be beat from a three phase PM servo motor.  my mill motor was $160 shipped, and weighs 60 lbs.  i was seeing sustained 500-600 watts out of it all last weekend!

adam

fabricator

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #70 on: March 26, 2012, 10:00:15 PM »
Bird house is absolutely right you will get much better performance from a servo motor, I can't remember who it is but there is a long thread about servo motors. I remember someone else buying that alternator and being completely disgusted with it.
I aint skeerd of nuthin.......Holy Crap! What was that!!!!!
11 Miles east of Lake Michigan, Ottawa County, Robinson township, (home of the defacto residential wind ban) Michigan, USA.

ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #71 on: March 26, 2012, 10:11:11 PM »
500 RPM- 68 v. x 5 amp = 340 watt
1000 RPM- 121 v. x 10 amp = 1210 watt
1400 RPM- 166 v. x 14 amp = 2324 watt

You got "took", man.  Big time.

This thing appears to have a stator resistance of about .35 ohm.  That means at 500 rpm clamped down to 14 volts it's going to try to put out 160 amps.

So I assume you're either planning on upsizing your turbine to about 20 foot diameter, or you're going to buy a $800 Classic MPPT controller to be able to use this thing on a 10 footer?
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Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #72 on: March 26, 2012, 10:45:28 PM »
I live in the heartland of NC. We are a class 1 wind region. That means we average 10-20 MPH when the wind happens to be blowing at all. I needed a generator with the ability to create as many volts as I can get at low RPMs. This one is supposed to be able to do that. My turbine will need to be light and quickly responsive to make the most of these wisps of wind out here. Also... As I have said several times before I am using it to power my shed which I use once a week, not my home. One thing I am sure you will agree with me on is that this PMA will perform far better than my Ametek 40 vdc.  Im hopeing this turbine will behave more like an ultra-light glider than the jumbo passanger jets most you guys are used to and fly in your class 4 wind regions.

I spoke to the owner of the small company that makes these about your reactions to his product and he assured me that because of this string and my unusual design that he will be personally building my PMA...  so...we will see what the man can do... and what my design can do to take full avantage of his invention... We will see...I am all about exploration and not above eating crow...
« Last Edit: March 26, 2012, 10:57:03 PM by Steadfast »
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REdiculous

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #73 on: March 26, 2012, 11:46:26 PM »
What about your "design" is different? ???
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ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #74 on: March 27, 2012, 12:12:31 AM »
I live in the heartland of NC. We are a class 1 wind region. That means we average 10-20 MPH when the wind happens to be blowing at all. I needed a generator with the ability to create as many volts as I can get at low RPMs. This one is supposed to be able to do that. My turbine will need to be light and quickly responsive to make the most of these wisps of wind out here.

Look, for the final time, that is not how wind power works.  With a 5 foot rotor at Cp .35 @ 6 mph (assuming you can even reach that at 6 mph, which is doubtful) you generate 7 watts at the shaft.  If your generator is 90% efficient you get 6 watts out of the generator.  You got a 1.4 volt forward drop in the rectifier, plus wiring, plus battery charging losses, plus conversion losses in the inverter.  When it's all said and done you got yard art that might be going around but it's not making enough power to even cover the idle consumption of an inverter, or battery charging losses.

There's a reason wind turbines are called wind turbines - key word "wind" - they need wind to make them work.  It don't matter what PMA, or motor, or whatever, you got.  You can't squeeze blood out of a turnip.

It is apparent that you do not understand the first concept of building a wind turbine, which is that you have to match shaft power to load very carefully or it won't even work in 20 mph wind.  Small rotors need to spin, and spin fast, to make any power at all.  A 5 foot rotor running at TSR 8 @ 6 mph (which it is going to need to be at to even close to Cp .35) is running at 275 rpm.  At cut-in.  If you try to turn it at 80-100 rpm at 6 mph it won't even make 1 watt.

Do you understand this?
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Chris

dave ames

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #75 on: March 27, 2012, 12:13:37 AM »
One thing I am sure you will agree with me on is that this PMA will perform far better than my Ametek 40 vdc.

If I were the betting sort, I'd take odds on the Ametek 40 to win.

I agree they have a better mouse trap (we are the mice).

I'll be following along with interest to see how you get on...Perhaps he has a special golden PMA he 'builds' when a community forum is watching?  ::)

Sorry to be a Nay Sayer :-X

It's still good fun, dave

birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #76 on: March 27, 2012, 11:49:19 AM »
steadfast-
the general rule is: anything sold on ebay that is touted as the best wind PMA out there, is most likely JUNK!  also: anything that resembles a car alternator is most likely JUNK (unless you can electrically mod it like a member here jerry.  i believe he was doing individually rectified phases on units very similar to get higher volts/earlier cut-in). 

sorry if we all seem negative, however, it's actually much closer to being realistic.  we hate to see new folks spend a bunch of money to realize that their genny puts out a mere 30watts in galeforce winds. 

here's what i would start with if i were you:
http://www.ebay.com/itm/Fanuc-Servo-Motor-A06B-0501-B751-/320813001783?pt=LH_DefaultDomain_0&hash=item4ab1f1ec37#ht_500wt_934

it's roughly half the price of that "turbo watt runner XL plus deluxe PMA"  i think the motor above would hit 12v at around 120RPM.  specs are 2000rpm  144v 3ph  11A (stall)

now look at the price for the same motor new and in perfect shape...  they're obviously very stout/precise pieces of machinery!  :http://www.ebay.com/itm/FANUC-AC-SERVO-MOTOR-A06B-0501-B751-/200412233893?pt=LH_DefaultDomain_0&hash=item2ea98000a5#ht_1534wt_915

also, i know for a fact, that beyond cut in, these motors get stiff very quickly due to their laminations/design.  very robust.  sure they're japanese, but i've always thought the japanese are lightyears ahead with manufacturing anyways (birdhouse straps helmet on waiting for flaming). 

anyways, i feel like the fanuc listed above would be a perfect match for a 5-6' wooden carved three blade set-up.  guessing you could peg out at 300watts, and see 50 watts when the wind seems "strong"

adam

seilertechco

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #77 on: March 27, 2012, 12:04:18 PM »
I'm wondering what the reasoning is for light weight.  Is it only for ease of handling or is there some reason to be concerned with heavy construction?  I have a crane truck myself so weight is a very small issue and I tend to build heavy.  I certainly understand the weight issue in aircraft, but why does weight matter if a tower is correspondingly heavy? 

Good luck birdhouse.  Toby

ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #78 on: March 27, 2012, 12:13:25 PM »
it's roughly half the price of that "turbo watt runner XL plus deluxe PMA"  i think the motor above would hit 12v at around 120RPM.

Guys, you can't cut a 5 foot rotor in at 120 rpm.  It won't work.  Period.  10 foot rotors cut in turning faster than that.  The Tip Speed Ratio at 120 rpm is only 3.5 for a 5 foot rotor.  For a 12 foot rotor that same rpm is TSR 8.5.  You need to be at at least TSR 8 for cut-in or it won't work.  With the blades turning that slow, the wind just slips right thru the rotor and you can't extract any power from the wind.

Find a motor that reaches 12 volts at 300 rpm.  Then you got something that will work for a five foot rotor.
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Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #79 on: March 27, 2012, 01:09:36 PM »
Birdhouse, thanks for your manners,  and the time and detail you put into your response.
I can see that you are trying to help and not just trying to "Be Right"....
And the others may very well be right too, but there manners make it hard to hear.
I am trying to learn here and to adapt to a level 1 wind environment as well...

Saying “Nah…it will NEVER work” is SOOO EASY to do.
I have learned to not always listen to “Nah”...
I have learned that trying to DO something about it is much more challenging...
Much more educational... and Much more rewarding... especially, if I actually end up successful!

When it comes to ancient artifact restoration, I have tried and successfully done many "impossible" projects as of late, in spite of all the times I have heard the phrase “you ignorant fool, you're wasting your time”.  And, I have confounded the "Experts" in the archeological world by successfully doing so.  I have even solved some pretty contentious debates in the archaeological community by being ignorant enough to actually try DOING something the way THEY did it back then, as opposed to talking about it what the dirt suggested “THEY MAY HAVE DONE”.  I did it by talking to the experts in all kinds of alternate fields of study, spring boarding off of their knowledgeable advice, and then applying their information to an ancient problem, (which was solved back in the day, but was lost in time).  And, now with precious little education, I am considered one of the premiere Biblical Bronze weapon restorationists in the world…
http://forums.silverseek.com/showthread.php?59372-The-Rediscovery-and-Making-of-LOST-Biblical-Cedar-Pitch-Glue!
and
http://forums.silverseek.com/showthread.php?13785-The-Biblical-Duck-Bill-Axe-restoration-project

Perhaps, just Maybe, a creative newbie, idiot, like me, who ignorantly does not just look at the wind and say “oh well” and throw in the turbine towel, just because I live in NC,  is exactly what this problem needs to become solved. Perhaps not…

We will find out…and I may eat crow...  It is my risk, and will be my reward or failure.
But I still need to stand upon your technical shoulders if I am to have even a slim a chance at success.

So, Again,
Birdhouse, thanks for your manners,  and the time and detail you put into your response.
The servo you showed is a great solution, however, it is also a massive 60 POUNDS heavy.

As (I think) Chris just suggested,
My turbine would have to be MUCH more heavy with a much larger sweep to move a servo motor of this weight and resistance. AND, If it was that heavy it would not respond to the lighter winds in my area.  "With the blades turning that slow, the wind just slips right thru the rotor and you can't extract any power from the wind."

My theory is that, in a lighter wind area, you need a lighter rig which can respond with more sensitively and poise to the wind. With a generator that is both light and efficiant in low RPM environments...

Just look how low the RPMs are, which this video shows, using the very PMA I am planning to use and the 9 or so volts it is generating even at that pathetic speed:
http://www.youtube.com/watch?v=NufJjkw5pRo&feature=channel

Am I on to something here...or am I still showing my naivety...


« Last Edit: March 27, 2012, 01:54:30 PM by Steadfast »
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ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #80 on: March 27, 2012, 01:35:29 PM »
As (I think) Chris just suggested,
in a lighter wind area you need a lighter rig which can respond with more sensitively and poise to the wind.

That's not what I said.  I could bolt up one of my machines with a 4 meter rotor and it will easily make 100 times more power than a little lightweight bumble bee buried in the turbulence and trees.  But your piece of pipe that you got for a tower won't hold it - couldn't even be used for a prybar to tip it over if it was laying on the ground because it's too heavy.

What I said was, you need a generator that will let your 5 foot blades run at around 300 rpm at cut-in and reach around 1,000 rpm in any decent wind if you want power from a wind turbine.  There is little power to be had at wind speeds under 10 mph, and the smaller the rotor the less power there is.

This doesn't have anything to do with ancient artifact restoration.  It has to do with physics, electricity, and some undeniable facts about wind power.  There is no free lunch with wind power and you are heading down the wrong path doing EVERYTHING wrong from having too short of a tower in the trees to having the wrong ideas about getting any power from light winds.

You can get SOME power in the trees with that short tower.  But it's going to take a turbine that runs fast to get it at 5 feet in diameter.  "Making the most volts you can in light winds" is only going to stall your turbine and it will not work.

I would suggest, before you proceed even one step further with this project, that you re-read Dan Bartmann's book, and also buy Hugh Piggot's book and read that too - paying special attention to all the math involved with getting a turbine to work.  You did not glean the necessary information that you need to build a successful turbine the first time thru.

That's what I'm saying.  You can lead a horse to water but you can't make 'em drink.  It is nice you are gung ho about your turbine project.  But you WILL end up with yard art if you don't change some of your ideas.  And when that happens you will abandon it in the end because of everything I'm telling you here.  You need to start with at least a basic understanding of how wind power works.  And at this point you have not reached that.  You're just bolting blades to a generator and mounting it on a pipe, hoping it will work.
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Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #81 on: March 27, 2012, 01:52:56 PM »
I also own some 5 foot long (10ft sweep) fiberglass blades and hub...
are you suggesting I use these instead?
« Last Edit: March 27, 2012, 03:30:35 PM by Steadfast »
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birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #82 on: March 27, 2012, 01:53:58 PM »
steadfast-
your welcome.

Quote
in a lighter wind area you need a lighter rig which can respond with more sensitively and poise to the wind.

My turbine would have to be MUCH more heavy with a much larger sweep to move a servo motor of this weight and resistance. AND, If it was that heavy it would not respond to the lighter winds in my area.  "With the blades turning that slow, the wind just slips right thru the rotor and you can't extract any power from the wind."

as far as a lighter rig for a light wind area...  i think thats a non-issue.  given the correct size tail, a turbine should face the wind much earlier than it starts producing electricty.  most of the furling tails used around here have the turbine not facing directly into the wind anyways.  seems like even 15 degrees of imperfection has little to do with performance, even though i'm sure that sounds hard to believe.  when the rotor (blades) really start ripping, there's a lot of contrifugal (sp?) force going on and many rotors will almost forget the tail and "wind seek" on their own.  it's been discussed many times here and seems the general consensus is don't worry much about it.  if the wind is strong, your turbine will face it, no matter what the weight (to an extent).  my mill is only 8.5' and TOO heavy, AND badly balanced on the tower stub, AND has nothing more than a pipe over pipe yaw "bearing" and it seeks the wind just fine!

that motor may be 60lbs shipped (probably overestimated for profit to seller), but i'll bet it weighs 50lbs out of packaging...  then there's an internal break that has to be removed.  this will shed another 10lbs.  so you'd be looking at a ~40lb motor. 

Chris O. is probably the best builder of the most efficient machines for high wind areas.  he has spent countless hours breaking the "rules" to create incredible 12' machines capable of multiple KW in reasonable winds.  so for him to see 120RPM cut in for a 5-6' prop for a 12v system sounds crazy, as the efficiencies are terrible.  in fact the machine will probably be in stall most of the time.  that situation might just be perfect you you in a low wind area, where you need (small amounts of) juice at low rpms.  the machine may never break stall, and if you designed it to be out of stall from the get go, say 250 rpm cut it, you may only see it produce electricity a hand full of times a year. 

that's rad that you have done some things in your career that are against the grain and produced good results.  however, this newest internet sensation of a car alternator PMA is NOT going to be another one of those breakthroughs.  i don't care who makes it, 11lbs of magnets, copper and steel are not going to produce.  is there a overunity portion of this companies website?   ;)  it's all about massive magnets and or steel, with thick copper that allow decent amounts of electricity to be produced.   someone correct me here if i'm wrong, but doesn't a typical hugh/dan 10 footer have almost 10 pounds of magnets alone in it?  and those are the light bits by comparison. 

adam




ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #83 on: March 27, 2012, 02:28:19 PM »
steadfast -

I made this video clip at lunch time just for you.  It shows you something that you cannot learn in any books, and only lots of experience building turbines is going to teach you.  I have that experience and I'm just trying to pass along what I have learned along the way.

This is a 3.2 meter machine (10.5 feet) in diameter on a 74 foot free-standing lattice tower.  It is located right in back of my house, out the back door of the utility room.  We have very turbulent and gusty wind here today that is varying from 10-15 mph with some gusts up to 18-20.  My APRS Wind Data Logging System showed the peak gust at 22.4 mph at 11:06 AM this morning, and the average at 12.1 mph for the day.

I happen to have some very advanced equipment with which I can "tune" a wind turbine to run any way I want it to.  And hence, I am able to show you what the real story is with wind power and how to design a turbine that works.

When I switch the power curves for the turbine towards the end of the video, in the background you can hear the transmission and generator in the turbine spooling up as it's allowed to run "free" at optimum TSR again.

--
Chris
« Last Edit: March 27, 2012, 02:38:52 PM by ChrisOlson »

CraigM

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #84 on: March 27, 2012, 03:16:09 PM »
Great thread!

So as long as I understand/accept the laws of physics, ohm's law and betz' law I'm pretty much free to go crazy and reach for the stars. This is where the creative fun starts.

CM
Brain engaged in Absorption Charge Mode... please wait, this may take awhile.

Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #85 on: March 27, 2012, 03:23:14 PM »
wow chris... how did you do that?  That...is impressive!

How can a mere program make your turbine spin faster?
and how can I design mine to be like yours?

Please explain what "in stall" and "out of stall" is, for me...
and how you manipulated it?
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birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #86 on: March 27, 2012, 03:43:53 PM »
spend $800 on a MPPT charge controller, and the world is your oyster! 

i wish i had a few of them, but my budget won't allow.  they are the cats meow though! 

stall is when the alternator is so stiff and pushing back on the blades soo hard that they never really get up to their design speed.  aka:  they're always working below their optimum. 

adam

ChrisOlson

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #87 on: March 27, 2012, 03:46:15 PM »
Please explain what "in stall" and "out of stall" is, for me...
and how you manipulated it?

How I manipulate it is very complicated and the topic of a whole different discussion.  My turbines are very high performance, geared, high voltage machines and they use a MidNite Classic 150 MPPT controller to allow them to run at much higher voltage than battery voltage.  I can program whatever power curve I want in the controller and change the operating speed of the turbine by "clamping" in the input voltage to the controller.  These machines run at 100+ volts in good wind on a 24 volt system.

Stall is when the airfoils on a turbine blade stop making lift from excessively high angle of attack.  A turbine blade is like an aircraft wing.  It is an airfoil and it creates lift.  When an aircraft wing stalls, what happens?  The airplane stops flying and it falls out of the sky.  The same thing happens with a turbine blade - it stops making power when the airfoils are stalled and not making lift.

A wind turbine rotor works on a pressure differential.  There is a higher pressure in front of the rotor than in back of it.  It also slows the wind down as it goes thru the rotor.  The wind contains kinetic energy.  The rotor extracts that kinetic energy from the wind.  When you extract energy from the wind and turn it into shaft power, the wind in back of rotor contains less energy than in front, hence the difference in pressure and speed.

With a very slow turning rotor that is running with the airfoils in stall it is impossible to extract much energy from the wind.  The wind blows right thru the rotor's swept area and just keeps right on going instead of being captured and converted to mechanical power.

Airfoils have to obtain a certain speed and angle of attack before they will make lift.  Operate the airfoil outside of its design range so it stalls and you may as well be swinging flat planks in the breeze because they will work just as well running on pure drag.

Smaller rotors run much higher rpm at the same wind speed and Tip Speed Ratio (TSR) that larger rotors do.  The most efficient rotors run at Tip Speed Ratios from 7-8, which means the blade tips are traveling at 7-8 times the wind speed.

Isn't all this covered in the homebrew books?

At any rate, let's say you have a 5 foot diameter set of blades that are designed for TSR 6 (that's a fairly slow set of blades).  At cut-in (lets use 6 mph) the blade tips are going to have to be running at at LEAST 8x wind speed to give the rotor a "head start" when the generator starts to lug it down (TSR) as the wind speed picks up.  You can build and tune your turbine for a specific wind speed and it will only operate efficiently up to that wind speed.  From that point on, without MPPT control, variable airgap, or some other method of power matching, the rotor starts to go into stall.  If you stall your rotor right off the bat at cut-in, she's all over before the game even starts and the turbine will NEVER make any power.

That turbine has to be RUNNING at cut-in to even have a snowball's chance of generating any real power.
--
Chris
« Last Edit: March 27, 2012, 03:48:30 PM by ChrisOlson »

JW

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #88 on: March 27, 2012, 06:26:06 PM »
Ive heard of people shorting the circuit in order to make the blades 'stall' doing this in high wind conditions, its commonly called shutting down the turbine.

Even so, in very high wind conditions a stator could burn up.

Quote from: Chris
How I manipulate it is very complicated and the topic of a whole different discussion.

Ahhhh, your now obligated to make a new topic :) j/k

I sure wish Flux would chime in here...

Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #89 on: March 28, 2012, 09:14:52 PM »
Today My father-in-law and I finished the tower and hosted it up for a test spin...
and look there is wind up there!


The pipe is 10 foot galvanized 1.5, inner-lapping at each joining point there is a 10 foot 1.25 pipe.
(that is why you will see the occational bolt going thru the pole)
so the pole is a total of 1/2 inch thick steel.


Here is the "Grabbing pole" with my wife's plans realized belt clamp.
By Hook or by Crook - Prayer, Persistence and Tenacity will win the day!

Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #90 on: March 28, 2012, 09:34:31 PM »
Here is the "door henge" furling and primary pivot Spot welded.


This is my birch wood tail.


That is it for today:
tomorrow I will be finishing up the turbine body and setting up the generator system.
at least that is the plan.






By Hook or by Crook - Prayer, Persistence and Tenacity will win the day!

fabricator

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #91 on: March 28, 2012, 09:49:19 PM »
Edited because of poor reading comprehension.  ;)
« Last Edit: March 28, 2012, 09:52:04 PM by fabricator »
I aint skeerd of nuthin.......Holy Crap! What was that!!!!!
11 Miles east of Lake Michigan, Ottawa County, Robinson township, (home of the defacto residential wind ban) Michigan, USA.

birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #92 on: March 29, 2012, 11:22:04 AM »
nice work!    you planning on guying that thing though?  looks like around 21' of un supported tower??    it's surprising how often we see unsuported towers bend right over. 

good luck over the weekend! 

you took time off plus the weekend for this right?  we love updates and pics!

adam

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #93 on: March 29, 2012, 01:09:44 PM »
Quote
i don't care who makes it, 11lbs of magnets, copper and steel are not going to produce.

I'm gonna give it a shot w/ a $40 treadmill motor that weighs 9lbs. Some Canadian folks made it and it's rated 1.5HP continuous and 2.5HP peak. I'm gearing up and going big-ish. We'll see.  :D
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birdhouse

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #94 on: March 29, 2012, 03:37:32 PM »
redic-
that was poorly written by me.  it probably will produce, just not much, even with gearing. 

i guess it all depends, some of us are disapointed with 1Kw, while other are stoked for 30w. 

we all do things on varying scales.  i just hate to see the chap expecting 300-500w when realistically they'll be lucky to see 50w. 

(all wattages above is just thinking "on a regular basis") 

adam

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #95 on: March 29, 2012, 03:54:57 PM »
Hi

Frightening. The only support I see for the tower is a twisted doubled up pipe clip, the tail look a bit small, the pipe joins look like screwed cuplings, and your assessing wind from a piece of tape tied to the top of the tower.

I have a 2meter unit on a 30ft guyed pole, depending on the battery it cuts in at 390ish RPM and is optimum at around 450 RPM 200W I have seen 488 W briefly on a couple of occasions. I suffer with turbulence like your going to, and when the thing starts thrashing about you can hear the blades and the vibration on the guy wires is unbelievable, you are hoping to absorb that vibration with two bits of plank nailed to the front of your shed.

When you finally decide what size blades you are going for, work out the total area as if it was a solid disc, then find out the wind loading on the disc for a given wind speed. then multiply that by the length of unsupported pole and look how much it translates to on your support. Add to that the vibration and gyroscopic forces being transmitted down the pole........

I have worked on VHF antenna mast and we had to calculate the wind loading simple co linear glass fibre cased antennas and the length of the arm they are on had to be considered.  I have been following this thread from the beginning and with all the will and enthusiasm in the world you cannot bend the laws of physics.  Light winds have no power in them strong winds can have destructive power in them. You don't design for the optimum winds you design for the biggest load of crapp nature can throw at you.  There was a company here in the UK that mounted 6ft turbines on the brick chimney stacks on houses there are photographs on the internet showing the chimneys lying on the ground having shaken apart the brickwork.

Brian


fabricator

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #96 on: March 29, 2012, 05:39:11 PM »
He has the pipes lapped inside each other and bolted, but the anchoring system is without a doubt a disaster that WILL happen.
The least that should be done is fasten it with a good strap with lag bolts at the roof peak and, get some band iron and make a U shaped bracket and get rid of that rube goldberg hose clamp night mare, make the legs of the U long enough to bolt through your horizontal pipe and put a bolt through the bracket to your tower too, you could use that bolt hole to bolt two band iron brackets that run back to your board on the building at about a 45 degree angle and lag bolt those to the board.

I aint skeerd of nuthin.......Holy Crap! What was that!!!!!
11 Miles east of Lake Michigan, Ottawa County, Robinson township, (home of the defacto residential wind ban) Michigan, USA.

Steadfast

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #97 on: March 29, 2012, 09:07:14 PM »
Thanks fabs..... I will do that...  I like you additional support structure.  I can hammer that out of rebar...
By Hook or by Crook - Prayer, Persistence and Tenacity will win the day!

fabricator

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Re: Light Weight Wind Turbine Project - as I build it.
« Reply #98 on: March 29, 2012, 09:22:38 PM »
Glad to help.
I aint skeerd of nuthin.......Holy Crap! What was that!!!!!
11 Miles east of Lake Michigan, Ottawa County, Robinson township, (home of the defacto residential wind ban) Michigan, USA.