Tusas Diversion controller

[Boss]

Kevin and I lowered the wind turbine yesterday, we needed to check some things. We re-balanced the wood blades using lead and tightened bolts on everything we could reach. We also checked the bearing play and magnet air gap. Everything looked great, although the wind turbine isn't generating anywhere near the power we though and hoped it would. We have some theories, most of which revolve around the blades. I know, if only I could build a wind machine as well as I can make a pun. Kevin, the man with the airplane knowledge believes the blades are stalling at the speed where we need the power the most. By "stall" we don't mean they are stopping, but the power curve tops out right at the point the blades should be removing an optimum energy from the wind.

The end result is we are seeing only 8 amps maximum in a good wind, when we ought to see 25 to 35 amps. Not good, in one sense, because the system isn't producing what it surely can. But on the other hand it is working and we really do not have anyway to cope with the full power output of a properly functioning wind turbine right now. I propose we move past this problem with the inefficient blades, and take solace in the obvious obstacles overcome by getting our first wind turbine in the sky and keeping it there. We need to keep on moving ahead, and not with our setup, with the next turbine, one build with mostly store bought pieces. We built a turbine by cutting every corner and fabricating everything the DIY way, now we need to test the process by building a wind turbine with some pre-cut parts.

After we lowered the wind turbine and tower and then raised it back into place yesterday, Kevin and I worked on the dump load controller, on the off chance that the turbine would suddenly begin to remove more energy from the wind and we would need to  be prepared by having an automatic method for removing the electricity from our battery bank before becoming over-charged.  We had build GHurd's Diversion load controller the day before, and this time it worked on the first try.  



That's GHurd's diversion controller on the right, which we mounted in an old intercom box with the power FET (transistor) on the left mounted on a heat sink from a stereo or VCR or something left over from the Outland Tech days.



Here is the diversion controller installed on the makeshift electrical box we will use for all the wind turbine electronics such as they will be in our limited test bench setup. Unfortunately, the camera battery didn't last long enough for the diversion controller to kick on, but you can see the green LED power light, and Kevin is holding our test dump load which  happens to be a 12 volt high intensity head light from a car wired in series to handle the 24 volts that our wind turbine alternator is configured.



We arbitrarily set the voltage we want the diversion controller to come on and begin to discharge the batteries. As it worked out it is 25.15 volts. The batteries won't reach this voltage unless the wind is blowing strongly, as it was yesterday, indeed this was the first time the turbine had boosted the battery voltage up past 25 volts, so it was perfect timing. We did see the diversion controller turn on, albeit for a minute and less at a time.

After this test we looked at the way our batteries were configured and Kevin came up with a better way to wire them, creating a even charge to all the batteries at the same time. Today will be the test of the complete system, we hope the hitherto irritating wind blows its ass off today so we can see what happens.

Smiles

--

Read the entire BMN and comment leave comments at http://outfitnm.com/category/brians-morning-newsletter

The End

[richhagen]

If your ultimate diversion load is larger than your generation, then the highest voltage you would reach would be 25.15 volts, and to me, that seems low for most types of lead acid batteries, and especially for flooded batteries.  It would of course be analogous to 12.575 volts dumping on a 12V system.  Powering some lights for plants and my laundry room, I have a small 12V system, when I was running it with a resistance diversion load, I cycled between about 14.4 volts to kick on and about 12.6 volts to kick off with flooded batteries.  The load dropped the voltage down pretty quick, so the battery was still essentially charged when it kicked off.  That same system is currently solar only and the contoller just opens when the voltage hits the top end, so there is no diversion load needed at present.

I am happy, as I am sure you guys are, to see that your system is finally up and running.  It has been interesting thus far to read about and see its progression.

 Rich

[Boss]

Thank you so much for the comments Rich

So to change the diversion voltage we would change Rx in Ghurd's controller, right?



From Glen's site http://ghurd.info

"When assembled for use as a Dump Controller, when it reaches the set voltage, power is sent to a dump load until the voltage falls some, and then the dump load is turned off. The cycle repeats as the charging current increases the battery voltage.

For example, a dump controller set to 14.3V with a hysteresis of 0.1V will turn on the dump load when the battery reaches 14.3V, and keep it on until the battery drops to 14.2V before the load is shut off."

Of course we are barely at the experimentation stage of real world readings, but we are already  seeing all sorts of things which are shedding light on what we have been reading about for two years.

Yes, we are using EverStart deep cycle flooded cell batteries, configured in parallel  pairs, for 24 volts  for a total of 660 AH. I decided not to buy a properly sized 24 volt inverter right now, because frankly we haven't any money to work with.



AIMS 300 Watt Pure Sine Wave Power Inverter 24 Volt Model # PWRI30024S

I've been looking at this one, for temporary to run the refrigerator and entertainment system with a combined power consumption of 280 Watts pretty much continuously, according to our handy Kill-a-Watt meter.

My idea is since we have grid power we can save a few dollars while consuming the little bit the turbine is producing.

One of my buddies is considering this device CNC router by Vortech routers



He wants to use a Solidworks design we made last year to cut blades with this.  

 

[wooferhound]

To set the voltage that diversion starts at just get a screwdriver and adjust the Blue Variable Resistor.

[independent]

You won't be able to run a normal fridge straight off a 300 sine wave converter. The motors are inductive and require a massive surge current each time they start up (a few times an hour). Google it, you'll see. Better yet. Start your fridge with your kill-a-watt attached and look at the "maximum" watts consumed

[Dan the Handyman]

Hey Boss,

 Isn't buying a CNC router the opposite of renewable energy? Maybe this should be on the rants page, but spending major dollars on a machine that would take decades to pay for itself seems a little over the top. I like pretty blades, and am a tool hound myself, but all of my renewable energy projects are from garbage, or off shoots of my job as a handyman/carpenter. ie my table saw, router, bandsaw, etc...

 I ain't king of the hill here, this is just my opinion.

 Dan the Handyman

[tecker]

You can tell a lot with a scope  on each phase.Take a look at the AC wave form under load also look at the rectified dc open circuit. I don't know how you wired the stator.TGhat would be good info on realizing the 24 volt charging .  

[Boss]

Yes, I agree, a CNC Router is way over the top, I really enjoyed carving the blades with a draw-knife at the OtherPower workshop last year. I can think of nothing more pleasing than using olden-time hand tools myself, but what can I do, the guy wants to be involved? He hasn't bought it yet, and with your encouragement I will suggest he rethink the CNC router. Like I said, I was happy with a draw knife, he thought a band saw ought to be used, and the blades came out poorly because of that, in my opinion.

   

[Boss]

The stator is wired in wye-star 24 volts 70 turns 14 AWG as shown in the home brew wind power book. Yes, I have a quad input scope I can check the wave forms, I'll check them out today, as I think I am out of work again, I sub contract as a WIFi installer in this mountainous region of New Mexico, and business has been slow lately, poor, poor me, I know.

[wooferhound]

You can always go Low-tech and carve your blades with a Chain saw . . .

http://www.fieldlines.com/story/2008/8/4/105522/4890

[ghurd]

Looking Good!

Like Woof said.  The blue pot adjusts the voltage.

Turn the pot screw clockwise to increase the voltage where it starts dumping.

I would set it to at least 28V with flooded batteries.

G-

[oztules]

Woof,

This is a direct link without the 9 pages of comments:

http://www.thebackshed.com/windmill/articles/ChainsawBlades.asp

[trader dutch]

Boss  pass this link on to your friend as to rethinking on a CNC. He may all ready have it but this is more fitting to our diy comunity. And save some big buck's

http://www.cnczone.com/forums/index.php

[Boss]

alrighty on adjusting the blue pot clockwise for an increase in dump voltage set point. Thanks

Glen, you included four diodes Shockley diodes. can you explain how to add them to the diversion controller circuit for operating inductive devices like the relays?

Thanks again for the help

[ghurd]

For relays, they are often called flyback or freewheel diodes.

They go reverse parallel with the relay coils.  The stripe goes toward the battery positive.

Some relays, such as those used in electronics, sometimes have the diode built in.

Power relays usually do not.

To the novice it appears the diode will never do anything.

The water analogy is the water hammer arrestor, which also looks like it would not do anything.

Schottky diodes are arguably best for flyback / freewheel diode use.

The amp rating of a flyback diode can be less than the current carried in the inductive load.

I believe I sent 1A 40V Schottky diodes.  They will be plenty.

I believe I also emailed one of my world famous MS Paint sketches about flyback diodes?

G-

[Dan the Handyman]

I was actually thinking of putting a piece of wood on the back door and letting the dog scratch it until it got to the right depth, then move it up so he can carve the next section.

 Dan the Handyman

[wdyasq]

I've built 4 CNC machines myself and make cut files for a $1/4 million plasma cutter. I have also carved props for airplanes and wind machines by hand and by CNC machine.  

None of you have had any complaint about having steel disks cut by laser, plasma or water-jet CNC machines. We all use (and many miss-use) chemicals to secure the magnets, encase the coils and protect the metal and wood from 'the elements'.

Those 'elements' are part of renewable energy.  .....

A CNC machine is great for repetitive work and doing things more accurately than can be done by hand. It is also satisfying to be assembling and  finishing parts while your NC machine is cutting more.

IMO it is STUPID not to use technology available. If you want to be pure, shove your computer where the sun doesn't shine, throw away all of your powered tools and use only tools made by hand. Buy them of local materials too..... It won't be long before you spend all of your time trying to kill small animals with falls and snares while your significant other keeps the kids and maintains the fires. You will soon grow tired of un-spiced roasted and clay-baked food and skinning things with a flint knife and your teeth.

Then ask yourself is it really that it is not 'RE' or is it you have wealth envy and don't want others to enjoy things you can't afford or can't operate. Trust me, it takes MONTHS before one will start to understand the complexity of a CNC machine and many run them years without the knowledge of how and why they move and cut. It is not a simple process. It is not intuitive on how one works and how to hold down the parts. Folks spend a lot on training, and rightfully so, after spending $5-50k on the tool.

I'll guarantee running a $50 bit into a screw you used to hold a part makes you heart sink the first time you do it. The 50th time you do it you will be mad at yourself, as you should no longer be that ignorant.

If you are a competent wood worker with lots of hand tools and buy a CNC router,  it will not be long until your router bit collection becomes as valuable as your hand tools. Except your router bits are mostly throwaway stuff unless you find a good tool sharpening service.

You will also begin to understand why they charge so much and why you only thought you could do proper CAD drawings. You will begin to appreciate the thousands of dollars of software it takes to operate efficiently and deal with folks you would love to help but have to make a living and pay for the tool, the software, the router bits, the electrical bill and still make that sign the Church or the Boy Scouts asked about .... was that last year....

Ron

[Bruce S]

RON;

   I certainly don't want to start a rant here, but kinda over the top on the put the computer where the sun don't shine don't you think?

Keep Smiling

Bruce S

[wdyasq]

Actually, I think it is an understatement. Here this fellow is using a personal computer and the Internet which POST DATE NC controls and complaining about machine carving not being 'pure'. The same place that computer can be imagined going should have the company of his 'Skillsaws' and routers as well as anything that uses electricity.

Perhaps he should try hand delivery of communications or carrier pigeon. He should write with the appropriate tool too - maybe try quills and make his  own iron and oak  Gaul ink.

Heck, using a CNC machine is no more 'un-pure' than  reading if one goes back about 200 years. Let's get real, electricity and solid state devices are pretty modern and 'we' as the collective of home researchers and/or builders of windturbines, are really on the cutting edge of something we believe just may help the world.

I further suggest if someone doesn't want to use the best and most modern tools they can refuse modern antibiotics if they get sick and become real pure real fast.

At least in that manor they won't be telling folks not to use tools that can save time and labor IF they have the resources to own/use them (money doesn't make one smart .... look at our political class).

Ron

[Bruce S]

Ron;

  I think I understand where you're going with this.

I read & reread the statement several times, I couldn't find anywhere that he (DTH) implied the guy (BOSS and friend) were wrong in using the 'mill. Just that for RE might be over the top?

If (DTH) had, I'm pretty sure he (BOSS) would've called him on the carpet about it.

DTH did state it was his opinion.

Both seemed to agree that using the draw knife was much more fun.

[Boss]

Howdy

I set up a scope and observed the waveform. it looks a little like a sawtooth pattern, and consistent for all three phases.

We adjusted the pot clockwise a little at a time, bringing the diversion set voltage up until the turbine isn't turning the dump load on and in a 15 to 20 mph wind the voltage is now stable at 25.86 vdc. we  are waiting for better wind to see what the voltage goes up to

the amperage after the rectifier is still 5 to 8 amps

[richhagen]

I think if I were just going to make one blade, or even one set, I might hand carve it.  But if I want to make a whole bunch of something, and make them all the same, or if I needed a higher level of precision than I could readily make by hand with my limited carving skills, then CNC is the way to go.  I had a project where I made about a thousand of the same small parts.  To make that by hand would have been tedious, and boring to no end, but with CNC, once it was set up, all I had to do was chuck in the new blanks, lube the machine and let it do its thing.  It was still a bit boring just changing out the parts, but it was manageable.  I would not even think of taking on a project like that without CNC.  Rich

[Boss]

Thank you for that Ron

We do appreciate the words.

I do love my hand tools, but I am all for mechanizing processes. I still have a bumper sticker on my mechanics tool chest which reads "Get wise computerize" and that was from the 80s. All tools are good tools to the trained and talented

Lucky for us that my partner taught Solidworks in the local Community college. Also they had a nifty 3-D printer and a small CNC milling machine for us to play with.

 

[wdyasq]

The 'theory folks' claim one can get another 30% in power output by going to the proper airfoils. If so, it will be worthwhile.

I dearly love my hand tools and enjoy working on good material. The comparing of shape to template and slowly 'getting there', watching the airfoil evolve feom a block of wood is a pleasurable experience. I can get three blades with a Clark Y, 44XX series  or USA35 type 'good enough' for a wind machine.

I can't hand carve an airfoil with a reversing 'power recovery curve' transitions, and twist as accurately as necessary to try the theories. I doubt I could hand carve three that were the same.

My main complaint is what is 'over the top' .... communicating by electronic text methods or using a CNC machine? I personally think folks did a lot better job of research when one went to the library, wrote letters and followed up with phone calls (when one could easily run up a $500-$1000 a month long distance phone bill researching). Using a computer, searching the Internet and reaching a conclusion yields faster results and one 'covers a lot more territory'. One also looses the time to reflect and think about a salient point the week or so it takes to 'get the new book' or have a letter answered.

The old method also filtered out many of the 'flipping idiots', those lacking the thought process to actually design and build things. But, we also have near instant access to the designer that drew a near impossible to follow set of plans.

One can't turn back the clock. The tools and materials are here and we should use them. I'm all for Dan the Handyman perfecting his dog scratching a set of airfoils out. I just don't want to afford the time of training dog to do that and then the time charge by the hour for the parts.

Ron

[tecker]

Take a picture of the wave form no load of the retified dc and post if you can .

[Boss]

I took several, but my old camera isn't fast enough to catch the image, I keep getting the trailing edge of the waveform. Like I said though, it is saw tooth under load in a 15 MPH breeze, less than that wind speed the waveform is notched ewually top and bottom on all phases, once the wind picks up the waveform get clean albeit somewhat trapezoidal (saw toothed looking) The reason I keep mentioning this is I can't recall what the waveform looked like on the scope we traded to Dan B while we were up there in Colorado at the workshop last year, was it a sinewave? I don't think so

Brian  

[tecker]

 Maybe at some point you could post some pics of the waveform ,but this is not a problem really the unit looks good and you can charge 12 volt batteries I would say that is a really good start. From now on it will just get better for you .As a rule I bring out the wye  tap each phase  as a neutral there are many ways to make that work for you like boosting or wye delta etc .I know it's been tough getting it up in the cold of winter . Hang in there.