48v up and running finally

[PRedATor]

I am pleased that this project has come to an end. (maybe)

Here it is up and connected to batteries to see how it produces some juice.

Is producing between 2-5 amps in a light breeze today, need some stronger winds to see how it goes.

Tower is holding well and raised with no trouble, although I don't like the death rattle when it gets to verticle with a sudden stop.

Thanks for this site and the people here for all the great info, I have done alot of reading while doing this project.

The tower is about just over 20m.

Look forward to the feedback etc.

cheers

rich

[Flux]

Gereat job, should be some nice clean wind up there.

Flux

[MountainMan]

Congrats on  your success and thanks for the pictures.

Can you explain for a newbie what the metal member that runs from the base of the pole out to one of the guy-wire anchors is for?  Is this a mechanism to make it easier to raise and lower the tower?  I don't get how it functions.  Seems like the same could be accomplished without the bar.

thanks,

jp

[Experimental]

           Again Rich,

       Super good, and boy -- you are going to get LOTS of clean air, up there!!

      I also like your place, looks like you have lots of room to play !!

      One thing I urge you to do though -- Ground the tower, and all the guy wires with grounding rods, and  about #4 wire --- after haveing a lightning strike, takeing out one of my gins, three days after I put it up -- I take grounding, real serious !!!

     I also, disconnect the power wires, durring lightning storms --- But my cabin is in a SERIOUS lightning area !!!

     240 watts, in a light breeze is real impressive too -- Great work Rich.. I,m full of envy and compliments ....Bill H.

[Nando]

I congratulate for a job well done -- the photos show a good job well done.

I am curios about your generator.

Can you detail your generator parameters ?

Also what current level at peak designed RPM and what would be the voltage if at that peak RPM the generator does not have any load.

I am guessing that at that peak RPM the charging power to the 48 volts battery may run around 50 % or a bit less -- 50 % dissipated by the generator and 50 % dumped into the battery --

What is the wire size coming down the generator to the battery and the distance between both.

Thanks

Nando

[PRedATor]

Hi jp,

Yes the gin pole is for aiding the raising and lowering of the tower and makes it easier to attach the guy's from it to the anchors, also takes alot of stress off the guy wires when initially getting off the ground.

rich

[PRedATor]

Thanks Bill,

Yes I have to get on with some lightning protection which I will do the trenches for the rods when I put the conduit in the ground.

Yes we like our 20 acre's alot.

rich

[PRedATor]

Hi Nando,

The generator is a 5 phase PMA with 24 neo mags 50 x 36 x 10mm and 10 coils (0.8mm x 270 turns each)as per Hugh's plans with some mods and changes as I put larger blades on.

The blades are now 2.9m in diameter (they used to be 3m)

There is a post earlier on about my unloaded volts etc when I was testing it, from memory I think turning it by hand to about 120 - 180 rpm it was sitting near 60 volts +- 5v

Now looking at it in the air and counting how many times the blades turn in a second roughly it reaches 48 volts at about 120 and anything over that the amps come in.

According to Hugh's plans at 500 watts I will be loosing about 7% at 300' in the wires (I'm guessing a bit less for me as I'm a bit less in distance)

The cable is 10mm ^ 2 Cu wire and the gen is 80m (including tower) from the battery bank.

Still waiting for some strong wind.

cheers

rich

[Nando]

Still, I need to understand the 5 phases, so please tell me how many diodes rectifiers do you have.

I would like to know how the coils are connected to "see" the 5 phases.

Regards

Nando

[Experimental]

       Hello again rich,

     At electrical supply houses, they have ground rods, about 6' long (copper or zink plated)   You simply pound them into the ground and use a "birney" clamp, to run a wire to the base of the tower !!

     I also put one at each guy wire hookup -- they aren,t cheep, but worthwile !!

     Perhaps you already know this, but you mentioned a trench for the conduit, and you want to keep the ground rods away from that -- and you only need a large hammer for the rods -- I use a T bar, fence post driver ...

     Would be glad to help, but you,re to far away for a weekend drive !!

     My best to you, Bill H......

[elvin1949]

 just a note

Run water around the rod and jiggle it up and down.

Unless you hit rock it will go down without driving.

later

elvin

[PRedATor]

There are ten coils which all the start wires of each coil are connected together with a common wire creating a ring at the centre of the stator next to the coils.

Then 2 end wires from 2 coils picked at random (2 coils that give the best voltage) are connected to a rectifier.  Thus giving you the 5 phases, which then the + 's and - 's out of the rectifiers are connected together to run to the batteries.

It took me a while to pick out 2 wires from the stator to give me the same and best voltage from each pair as some gave poor results and some good, its just finding that combination.

Hope this helps

rich

 

[Flux]

Nando

The 5 phase rectifier has 10 diodes, like a 3 phase bridge with 2 extra arms.

In this case there are 20 diodes (5 single phase rectifiers).

The 10 coils are arranged as a parallel 5 phase star connected. The 10 coil ends are connected to two 5 phase rectifiers in parallel. It is possible to parallel the coils before the rectifier but with less than a perfect winding there are circulating currents which delay start up. Using 2 rectifiers isolates these currents.

The 2 coils could have been series connected with half the turns of thicker wire and a single rectifier used, but the 10 coil star arrangement is simpler for beginners to follow, all coils are the same and any wire can go to any rectifier.

The 2 voltages mentioned occur because if you take a pair of wires at random you can get a vector displacement of 72 deg or 144 deg. This sorts out in the rectifier as commutation takes place to the highest next voltage that comes up.

Flux

[PRedATor]

I tell you now, there is no way I'm going to pound a 6' rod into this ground.  This is Aussie soil here I'll be lucky to get 2 feet in.

Even the post hole digger could only go 700mm deep for my footings for the anchors.

The rod will have to go horizontal in a trench.

cheers

[Experimental]

     I see, sounds like the ground around my cabin (three feet of dirt and 1/2 mile of rock !!)   I did manage to get about four feet in, and tried Elvin,s trick, but that rod would not move -- up or down !!

     I cut the last foot off, and just water the spot every few days, and have about 6 rods -- one went all the way...

     I,m just nervous about lightning, after having it hit my gin, about 100 feet from the cabin  --- By the time the echo stopped, I was about 1/2 mile away -- still running !!!!

     When I hear thunder, I get real jumpy !!   My best to you, Bill.........

[picmacmillan]

real good job predator...hopefully i am right behind you with a 48 volt machine...i have all the mags and parts, but need some time to get it done...again, hats off too you...pickster

[Nando]

RICH & FLUX:

Thank you for the info, this 5 phases with 10 coils, pair paralleling make the generator to start producing late in the RPM.

It would have been better to have the pair coils in series adding to produce the double voltage, therefore being able to generate charging voltages earlier in the RPM curve.

With a good MPPT charger controller one can attain much higher efficiency in the 70 to 80+ versus 50 - % directly connected to the battery bank with a controller like the C40 or the C60.

Maybe I am analyzing it the wrong way.

Regards

Nando