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3 phase AC wind generators, turbines, grid tie connected with NO battery Answered

I have a number of 3 phase ac motors with fans on them from a large commercial greenhouse. If I put them out in the wind they spin the motor and put out 3 phase ac. I would like to know how to connect the 3 phase ac from them to grid tie with NO batteries. 


If the motor is built to the right rpm (low rpm and high voltage is good) then all you would need to do is make a rectifier with the right size diodes to make the ac current into DC. Then wire that dc current to a grid tie inverter (synchronous inverter) of the right size. Check the laws and rules of your power company before you hook up, for example consumers power in michigan requires me to file paperwork and pay a $70 fee.

For small power levels you could probably use something like this MICRO GRID TIE INVERTER for 3 PHASE ALTERNATORS: http://cgi.ebay.com/NEW-MICRO-GRID-TIE-INVERTER-3-PHASE-ALTERNATORS-/110576211797?pt=LH_DefaultDomain_2&hash=item19bedb1755. It rectifies your generated AC, and then it converts the DC it into 120VAC at 60 Hz to feed into a standard AC outlet..

In-line with the previous two answers: you don't connect to the main grid without proper equipment & regulation. "They" won't let you mess with it on an amateur-basis, and "they"'ll probably prosecute you if they find you trying.


Mind, you'd have to do it properly to get paid for your input.


Forget it, to grid tie them, they have to be spinning slightly faster than their synchronous speed, or they will break sync and and absorb energy FROM the grid. Tying to the grid is NOT trivial. There are complicated issues involved.

You need your system installed by a licensed electrician and permits from your electricity provider.

But your generators aren't going to be 60 cycle you you'll have to install some sort of phase converter since they don't like you feeding in electricity off phase.  Big money for that item.

You have to use a transfer switch that will properly disconnect your equipment from the grid anytime the grid is off so that anyone working on the "dead" line doesn't get a surprise.

In the end it would probably be better if you didn't connect your stuff.  I doubt that the fans would turn them fast enough to generate any appreciable amount of power, especially if you were draw a current from them. They get harder to turn when you draw current from them.