7 Foot Axial Flux Wind Turbine

Step 8 Controller

At first I was going to build my own controller, as I have shown in the pictures below. The project shifted locations, though, and I decided to charge a battery instead of heat water, so I decided against it. I did have a rough idea of what I was going to do, but I think not making the controller on my first turbine was probably a good decision. Things can get dangerous if your controller fails and lets your turbine run away at reckless RPMs. Also, believe it or not, electrical permits prefer stuff that's UL listed... who'd have thought that?

Instead of heating water, I decided to charge a 12 volt battery that would be hooked up to a light. This cut down on costs, logistics, and other restrictions that made it a bit easier to install. I settled on using two Xantrex C40 charge/dump controllers. One regulates the charge coming in and the other watches the charge level of the battery to ensure it is not overcharged (it can't do both at the same time). I have a 12 volt dump load that is a water heating element, rated for 600 watts.

I used a three phase disconnect switch as the "brake" on the wind turbine. When the switch is closed, all three phases of the wind turbine are shorted out and it will slow itself down. I also used a 750 watt modified sine wave inverter to run the light. The light has a photoelectric eye on it and is wired up to turn on at night.

Comments

[kbooth23]

Hey im loving this instructable, the wind turbine at my college got me interested in building my own. I thought this looked very do-able until i got to this step. I was wondering how much the controller and other parts in this step costed, and if it was difficult to assemble them all?

[brokengun]

I can't remember exactly what I paid for them. I think it was in the range of $120 each. I bought two, but only ended up using one as the charge controller. I used a bridge rectifier and a schottky diode to rectify the three phase power coming off the turbine. The controllers weren't hard to hookup the manual that comes with them is pretty good. There isn't any assembly required, just wiring the wind turbine up. I think I had to change the position of a jumper and that's about it, there are small potentiometers to change when the dump load is turned on (by checking the battery voltage).

I've really gotta update this thing though. Currently the turbine is down for repairs, a weak spot just above the weld on the tail's hinge pin gave out. I plan on redoing it almost entirely at some point but college has been keeping me busy.

If you've got any more questions, feel free to ask. One thing I can definitely say though is if you don't want to be constantly maintaining the machine make sure you don't cut corners. Do it right, or do it twice.... sometimes you gotta learn the hard way, eh? Best of luck.

[0087adam]

That looks really professional...