3hp 3ph Conversion

[behoof]

3hp 3ph Baldor Permanent Magnet Conversion

After assembling this Permanent Magnet Conversion Generator we mounted it back in the lathe to do some testing of its output.

We purchased a 1200 volt, 140 amp, 3 phase Bridge Rectifier using Ebay for approximately $40.00USD + shipping. We did this so as not to have to build the rectifier bridge as another project. Not necessarily better just a shorter path.

We took a 12volt computer processor heat sink with fan and zip-tied it to the new bridge for cooling when testing. As a side note, if you look in the picture behind the bridge and heatsink you'll see a green dimpled cut piece of plastic. Just to share a great idea with you all, what that is is a two liter pop/soda bottle we used for shrink wrap when installing and uninstalling the magnet rotor in and out of the case while working on it to protect the mags from damage. The way you do this is just cut off the top and bottom and slide the remaining bottle body over the armature and use your heat gun or hair dryer and shrink the pop bottle down till it fits tightly over your armature... when you're done with its use just knick it with a knife and peel it off, it doesn't stick at all... pretty slick really and works great!

Next we zipped the bridge with heatsink to the lathe cross-slide table and then wired the generator. Fortunately when chucked up in the lathe fully assembled this generator fit very nicely to the ways with a piece of 2x2 as support and rotational stop. Kind of lucky really.

This is just a picture of the setup we used.

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(Note to self: Notice on Cut Red Wire, When using a 12 volt computer fan be sure to not exceed 12 volts. 183.1 volts certainly does make a 12 volt fan spin quite rapidly just before the smoke gets out.)

All the testing was done either open voltage or with 2-12 volt car batteries in series for 24 volts. The system this jenny will power is a 24 volt system.

Readings taken on lathe and with Schect rpm indicator to verify rpm  

8-18-07

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Wired 1-Y no load AC readings

RPM

95.         9.5  varying to 16.4
    
125.        17v        35.3v
     
165.        28v        42.6v
     
375.        77v        84v
     
590.        103v      106v
     
650.        127v      140v
     
     

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Wired 1- Delta  no load AC readings

RPM

95.         9.7v       20v
    
125.        17v        25v
     
165.        16v        24.5v
     
375.        44v        48v
     
590.        59v        61v
     
650.        74v        80v
     
     

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Next we wired a 140amp, 1200volt, 3-phase Bridge Rectifier

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Wired 1-Delta Open DC Volts

RPM

95.     14.4 volt
    
125.     19.2v
     
165.     26.0v
     
375.     61.9volt
     
590.     81.2v
     
650.     106.0v
     
     

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Wired 1-Y Open DC Volts

RPM

95.     26.8v
    
125.     35.5v
     
165.     47.5v
     
375.     107.0v
     
590.     140.0v
     
650.     183.1v
     
     

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Wired 1-Delta with 2 - 12 volt batts in series for  24 volts

Starting battery voltage was around 23 volts

317RPM  36.9volts at 8 amps

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Wire 2-Y with 2 - 12 volt batts in series for 24 volts

RPM

166.  24.99volt at .44 amp
     
355.  37.4 volt  at  8 amps
     
     

From here on our lathe belt started slipping so we were

unable to accomplish better readings until we repair

 the lathe but we did get a reading at:

RPM

370  38.8 volts at 9.33 amps

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The system that I have is a 24 volt system that has two battery banks. One is a set of 16 - C&D Liberty 1000's that are 100 Amp Hour SLA's, backed up by a Commercial 24 volt C&D battery charger system.

The other battery bank is a 48 Volt fork lift battery that has been split to be used as two 24 volt batteries in parallel. I also have another 36 volt fork lift battery that I'm either going to move to another location outside my system or split into one 24 volt that I could parallel into the existing 24 volt fork lift bank already mentioned and 1 - 12 volt arrangement. Interestingly all the batteries that I have, the fork lift and the Liberty's are manufactured by C&D Batteries as is the battery charger. The charger is temperature sensitive and does float, equalize and is totally adjustable.

It was also called to Kentt's and my attention that this jenny, due to soooooo many magnets on it,  may try to make too much power so we thought that we would purchase something locally that could be used to control our magnetic flux with little effort. But what to buy? What could we get inexpensively that would get this jenny under control if it is developing too much flux? Well, we ran down to the local neo-magnet store here in the thriving metropolis of Yale, Michigan USA and bought the last, very last can of FLUX REMOVER SPRAY.

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Now comes the next learning curve. How to design a 3 bladed propeller that will match this jenny. We're using a furling mount of the Hugh / Dans design but a bit modified for our face mount jenny. We're located in Yale, Michigan with an average 5 -7 mph wind and have the advantage of a bit of a wind tunnel effect here due to the topography and woods locally. Our tower is at 65' and easily above any trees and more than 300' from the woodline.

We look forward to any thoughts, questions or critiques regarding this project and especially any thoughts on prop design.

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[JW]

Behoof,

 I noticed you have 5-7 mph winds in your area. Is this at 65ft?

 You might consider a VWAT(with less of a tower) with a very low rpm cutin speed. And dual rotor genny. Id ditch the baldor conversion since your most likely going to need an overdrive of some sort. You wont need this with a properly designed dual rotor. And such a dual rotor genny may not be sutable for a horizontal machine.

 Most will just throw in the towel, because you have, (A) such low wind speeds in your area and, (B) your running SLA's.

 I have gotten excellent results charging my SLA's with a wallwort. I find anything like a (auto)battery charger will fry them in short order. Although 'my' SLA's or valve regulated glass mat batterys(12v) have WAY higher output than 2 6vdc trogens in parallel. They also have a way higher CCA.

 If you consider a low rpm VWAT, plan on making an eloborate battery bank(charging system) that gets fully charged, then powers your loads, while charging the 'other' bank while isolated...

 I have gotten output capacity results with my sealed glassmats, that far exceed what you can get with any flooded lead acid battery. These batteries are just very picky to charge. Flooded lead acid batt's are way more forgiving when being charged. If you were in a more windy area, youd have to divert to a dump load, to save your batt's.

JW  

[vawtman]

What is a VWAT jw?

 Is it a Vertical Watt Accumulating Thingy?Never heard of one.

[dinges]

Huh ?

A VAWT ? On a smaller tower (why the smaller tower; do VAWTs need less wind than HAWTs?). The Baldor would need gearing whereas an axial flux wouldn't? Couldn't the Baldor be rewound to give any voltage you want? Is a cutin of 95 RPM (1-Y) for 24 V too high? What kind of VAWT do you recommend? Diameter, length, for his windsituation ? Blade profile? What are the details for the windings? How many magnets, coils; what size magnets? You're obviously an expert so please enlighten us all.

May I enquire as to how many generators you have succesfully built, to be giving out that kind of advice? How many of those were VAWTs?

I'll do you a favour and ignore the battery advice. Trojans, btw. And as far as CCA goes... Who gives. Ahr is what we are normally interested in. Oh yeah, VAWTs, not 'VWAT'.

A few days ago you had me rolling over the floor laughing when reading your analysis on latent heat, charcoal, steam engines vs. casting ovens, etc. (the last alinea in that post was a gem...)

Very funny.

Unless it wasn't meant to be funny...

[behoof]

JW,

Thanks for your interest in my project, it's comments such as your's that help me to enjoy the learning curves and tribulations involved in such detailed projects such as these.

All the planning, material gathering, knowledge gathering and making the final design decisions based not only on gathered info but on the successes of my mentors.

I appreciate your thoughts but based on current knowledge and performance stats provided by others here I think I'll stick to my conversion and will probably build an axial based on the Dan's design. Hey, when you find something that really works, go with it, right?

You mention my wind but you may have failed to read the part about my topography and to be more accurate for you, any wind from the Southeast thru the Northwest is funneled straight at my tower (Bernoulli's Principle at its finest). The 5 - 7 mph was taken from a wind chart since I don't have a anemometer at this time, my actual is probably more like 7 - 9 mph but I don't like to pad or give false info.

Not sure what a VWAT is but I've seen some really GREAT VAWT's and I think building one would be a great project, just not right now... as we're gearing up to do Kentt's 10+hp 3ph next, that is unless he decides we're going even bigger... up to him.

My SLA's are JUST fine and live continually in line with a commercial batt maintainence system built by C&D Battery, an Allied Company.. same company that made my batts, all of them, including the 2 3000 lb Fork Lift batts that are my primary bank. But I appreciate your concern.

Anyway, best to you and good luck on your VWAT.

behoof

[Flux]

Nice work there.

Your wind speed does seem drastically low but as you haven't measured it then I wouldn't get too worried yet.

In view of the low wind speed I would use a larger prop than normally acceptable for that size of motor. Your biggest worry will be start up. That makes a motor conversion less of an ideal choice for low wind.

I would be reluctant to risk bigger than 12 ft prop, so I think I would try it at 12 ft and use something similar to Dan's with tsr6. your cut in for 1 star is low enough for 12 ft and if you can get it to start then I think you will do perfectly well.

You will need about 6" offset and you will need to furl early, although you will probably not burn it out easily.

Don't whatever you do go playing with speed increase transmissions, you will never start it if you do.

I make no comment about VAWTs I don't think you will do any good if the wind is too low for a HAWT to work but that is my personal opinion.

Flux

[behoof]

Flux,

Thanks for the comments. I think I should really clear up the low wind thing in my area. I have two little jennys up now, 1 is an ametek 72volt PMDC on my 12 volt system for DC lighting and the other is a Danfoss PMDC on my 24 volt system both have 5' blades (aluminum) and regularly give me me plenty of power in their respective systems.

I really need to get an anemometer up just for better info if nothing else. I appreciate your info re: blades and would really like to give you better info on my wind. As I've mentioned previously in posts I have a kind of unique location in that I get a really good wind virtually all the time caused by my placement of towers relative to a couple of big woodlots and a bit of a small valley the funnels kind of like a venturi right at my towers. We have prevailing Southwesterly's here and anything in the range of true North thru ESE really keeps my blades spinning. As I type my Danfoss is giving me over 2 amps and I don't have an ammeter on my ametek but it's happily spinning away also.

I don't know the numbers but my winds aloft must be awfully good because it's a rare day when my jenny's aren't spinning away and feeding my charge controllers enough to keep it supplying the batts.

Thanks again,

Skip

 

[JW]

WHAT...

 This one gets 7 smileys.

"Unless it wasn't meant to be funny...

Peter."

It was meant to be funny....

"JW,

Thanks for your interest in my project, it's comments such as your's that help me to enjoy the learning curves and tribulations involved in such detailed projects such as these.

Skip"

   Honestly, Im very impressed with what your doing there Skip/behoof.

On a seperate topic.

There are some barrier key's(islands) off of Biscanyne Bay, like Sands Key(north) and Elliot Key(south) that have primitive campsites. I would like to be able to pull permits to erect a wind turbine on one of those keys. Perhaps a group or club could sponsor such an endeaver. Then many people (who had a boat mind you)[from all over the US] could visit this campsite cordinated thru the group. It would make a fine gettaway for just about anyone.

"In view of the low wind speed I would use a larger prop than normally acceptable for that size of motor. Your biggest worry will be start up. That makes a motor conversion less of an ideal choice for low wind."

Thanks again, for saving me Flux...

By the way, the area I speak of, has variable winds on an average of three days a week, throughout the year, at 20mph. The problem is, somebody has to go out there during a hurricane watch, to lower the tower, I dont see that problem with the batt bank and invertor(atleast to save the machine).

 I bet a requirement for the permit would be, no gas or diesel generators, to prevent pollution, on such a small patch of dry land that is surrounded by water. I bet it could be done. The only problem I see is the welders, they would have to have a gas or diesel generator, for construction purposes.

Best to all

Jeremy/JW

[JW]

Biscayne Bay is very close to where I live, Miami, FL.

Jeremy

[JW]

Hi Peter,

"What kind of VAWT do you recommend? "

A Darrious.

"Diameter, length, for his windsituation ? Blade profile? What are the details for the windings? How many magnets, coils; what size magnets? You're obviously an expert so please enlighten us all."

ooooh'k

My uncle Ed was involved in a Small start-up, called Micro-Turbine. Anyhow he helped them create a mold for fibreglassing each vane(?) they had a total of 5(what looked like to me, well 'big blow horns') Same type of shape you'd see with that 'daniel boone' type gunpowder holder. The diameter of each circular vane was nearly 2ft in diameter. I believe the diameter with the 5 vanes was atleast 3 meters.

 This all took place in grandrapids Michigain. Anyway the actual inventor died, he's family inherited the debt from(there Dad) the credit cards used to finance the endeaver. So they had the right to confiscate all related materials. And so the whole thing vanished as far as I know. He's family was not as intersted in the idea as he was.

 My uncle Ed told me the device that was constructed during there incubation stage, would spin all day long. Im pretty sure from what I saw of the old web papers, was a darrious of some sort.

 Also Ed told me that before he died(the actual inventor of the profile shape they used) when they started to extract power from the unit, 'things went downhill from there' He told me the guy used a standard auto alternator with some sort of gear drive. He also mentioned, once this was done, the unit stalled often, which wasnt happening before. He then made it a point to state to me that whole spinning thing is like 300lbs. You cant exactly walk up to it and grab it with your hands and stop the thing.

After hearing about this several years ago, then later learning about how general cut-in speed is related to a single 'or' dual rotor machine stator diameter. It just made sense to me that one could extract power better from the machine they created, without the geardrive. But yes both horizontal and vertical machines need surface area to turn with a corrisponding horsepower. Doesnt the BENZ limit have something to do with this?

Jeremy

[Flux]

2A at 24v from a 5ft rotor puts you into the low wind category and if that wind is consistent as you say then | think the 12ft prop will work fine with your alternator.

If you went down to a smaller prop and used delta connection you would reduce the general output but increase the potential output during the odd ( few ) periods of higher wind. I think you will capture far more energy with the large prop.

Generally I am reluctant to suggest oversized props for the alternator for fear of what may happen in high winds. In your case it seems as though these occasions will be rare and as long as you make every effort to get it to furl early it should be fine. Use 6" minimum offset and make the tail of something light.

Flux

[Warrior]

First, Hats off to behoof for such excellent work. I can tell he made an extra effort to get things done well.

Flux, can you give a brief explanation as to why you consider the 48 watt output from his 5' machine to be from a low wind zone?

He didn't mention the wind speed but says his gennys are spinning quite often.

Thanks,

Warrior

[Flux]

Much depends on how effective the 5ft machine is. If it is very inefficient then I may be totally wrong about the low wind area.

Assuming that it is about right then it will produce that in about 12mph. If he never gets much higher winds and there are significant periods of this during the day then the average is probably about 8mph. Normally this would be quite disappointing but if the long periods are regular each day at 12 to 14 mph then it should do quite well. Many of the low wind areas have long periods of nothing useful, a few useful days and many that are too windy to effectively make full use of them.

Average wind speed is not a good guide without knowing the distribution, I think he may be in a lucky area.

Spinning often is meaningless. Many machines will spin with 3 mph wind and will never produce anything. The 48W figure is much more meaningful.

Flux

[Slingshot]

Behoof,

I see no one has commented yet on the soda-bottle shrink-wrap, which seems like an excellent suggestion, and could have many other interesting applications as well.  After reading your post, I went back into our lab and hit a smaller plastic bottle with the heat gun to verify how much "shrink" to expect.  

So, could you elaborate on your steps/procedure for getting the magnet rotor back into the casing?  Particularly your experience with the perils of the rotor wanting to stick to the side of the stator before it is held centered by the housing?  I haven't done a conversion, but have a brand-new 5 HP 3-phase motor that I've been saving for "something".

One question also keeps popping into my mind - like the Ameteks I've been using for years, these motors are probably designed to support perpendicular loading on the shaft, but not necessarily thrust loads.  Did you install a special bearing to resist the thrust loading of a wind-powered rotor, or do you plan to drive the generator using a belt?

thanks!

[behoof]

Slingshot,

The pop-bottle shrink wrap was a great tool for the in and out of working with putting the arm in with different counts and positions of mags before we glued them permanently. I'm certain that it save us a bunch of scratched mags.

We found that when install the rotor it took at least two of us to do it and feel safe that we wouldn't loose a finger in the process, LOL.  When we got somewhat close with the arm fully loaded with magnets as the first row entered the lams it was unavoidable that it would take a big leap and we found out early on that if we didn't keep control of it, it would literally 'fly' in. We also observed as best we could that as long as we payed close attention to centering the arm on entry to the lams that it seemed to stay off the lams. We removed it and inspected it carefully on removal and didn't see any damage. And although we would have liked to install it each time with a shrunk pop bottle on it, for the final install we decided to coat the arm with VHT paint as a protective layer.

The bearings we have in it now are the originals but we are considering going to Applied Technologies (formerly Detroit Ball Bearing) and see what they have available in a more versatile bearing for our application.

We will be installing this jenny on a 65' tower using a Hugh/Dan's varient furling mount. We're still trying to gather enough information regarding building a compatable set of blades for this. All the good people in the IRC channel are very helpful and really a great bunch of folks, that give a wealth of info.

Plan to use Michigan White Cedar laminated but the design is still up in the air. Flux has offered some insight and suggestions and I hope to get more from him and others on the actual design to accomplish the best design to match this jenny.

Thanks for your comments/questions and good luck on the 5hp.

behoof

[behoof]

Flux,

Based on information from zubbly and a few others I had intended to go with 11' on this using Alton's Calculator based on a design for two blades but using three. And just because, actually building 4 blades, one just in case.

Anyway, that being said, the actual design is a big concern and as you have mentioned, I'd really like to capture all the usable power that I can. So, being novice, the design characteristics are a bit daunting but I'm sure do-able.

Do you have any thoughts on design characteristics that could help us better utilize available winds? Perhaps a post by or someone's website that has a similar jenny up and is using a design they are happy with?

You have my specs on the jenny. The mount will be a furling mount with 6"+ offset using probably a 6'tail spar +/- and an aluminum vane. (Pretty much based on the Dan's/Hugh's design) I make my mounts using torrington bearings top and bottom and wire support down the center (free hanging w/no slip rings)with 3ph commercial plug at bottom for unwinding purposes also I balance the whole rig while on the ground so that the vertical and horizontal loads stay as centered as possible, of course, except for gyroscopic effect.

Again, any thoughts or help from all of you will be greatly appreciated as always.

Thanks,

behoof

[SparWeb]

Behoof,

Great stuff.  Lathe testing is lots of fun.

If you take another go at it on the lathe, you could try getting a torque measurement.  With your set-up it should be easy.  Put a knob or something similar on the end of the bar you attached to the housing.  When you spin the motor in the lathe, put a scale (like a bathroom scale) under the bar so that the knob pushes down on it.  It may be tricky to fit it all but maybe the bar could be on top instead of under the motor... just come up with something with right angles between the arm and the face of the scale.

Anyway, the length of the arm multiplied by the weight on the scale is the torque.  Torque times RPM is POWER.  Measuring the power will tell you +/- one foot the diameter of prop you need for the wind speeds available.

[behoof]

Hi all,

Thanks to everyone for your responses... really appreciate the interest and input!!

Just a note to add to my specs on this conversion...

We found that it takes 15 inch/lbs to start to spin after it breaks that slight resistance it spins quite freely really.

Any thoughts or comments will again be most appreciated.

behoof

[SparWeb]

I'm not sure if I wasn't understood in my previous posting, or if you're just posting that in addition to the other info you gave earlier...  Anyway, I suggest you should try measuring torque during operation under load on the lathe.  (If you already got that then sorry for being pedantic.)

On the other hand, when I tested my motor conversion (also a 3 hp, but with a much larger rotor) for starting torque against the "cogging", I got about 6 inch-pounds.  I tried a few different magnet configurations to get it that way.

I only just raised this converted motor on the tower, and the cogging noticeably prevents it from turning, unless a breeze is blowing, but it will start and turn slower the cut-in speed, so I haven't lost anything.  Your results may vary, if yours has a little more resistance.