AC to AC wind generator Inverter grid tie

[veggiepower]

Anyone know where I could find an AC to AC inverter designed for wind generators. I have a 3 phase AC flux wind generator and it seems like such a waste of energy to convert to DC and batteries then invert back to 120V AC for grid. The The Skystream 3.7 wind generator seems to be doing that, so I would think there would be a market for an external inverter like the The Skystream internal inverter.

http://www.skystreamenergy.com/skystream/

http://www.skystreamenergy.com/skystream/how-skystream-works/

[wooferhound]

The Skystream website is careful not to provide any details at all.

I really don't think it would work because it would have to synchronize it's frequency to the 50/60 hz grid power. which is already difficult for a grid tie inverter.

[binarycortex]

Maybe instead of batteries, you could go directly into a large capacitor then to the inverter, but then again maybe I'm wrong.

Ian

[wdyasq]

IIRC, Power-One has the proper inverter.

http://www.power-one.com/

Ron

[scottsAI]

Check out Breezy 5.5

http://www.prairieturbines.com/

Induction motor as generator works, normally need pitch control.

Above gets by without.

Have fun,

Scott.

[electronbaby]

The Endurance machines also do this. If you dont want to convert from 3 phase AC to DC then to AC again, use a different type of generator (induction motor).

[Rob Beckers]

Hi Veggie,

Both Power-One (their Aurora inverters) and SMA (WindyBoy) makes inverters for wind turbine grid-tie. Both brands are UL1741/cUL approved, so it can be done legally. For the WindyBoy you have to provide your own rectifier, Power-One has a rectifier available (same box also generates a frequency signal that the inverter then uses). Both are MPPT type inverters, the WindyBoy uses a 'table' of 2 or 3 points, depending on the model. Power-One has a true MPPT table of many points, that couples either voltage or frequency (RPM) to output power. Of course, the turbine voltage and power has to fall within the limits of the inverter, so it may or may not work for your wind turbine.

Feel free to contact me directly if you need more info about the Power-One inverters, I work with those (haven't used WindyBoy personally).

-RoB-

[veggiepower]

Thanks everyone,

Rob, if I have a cut in of 48 volts and max watts of 2000 would the Power-One inverters work? What about the cost of a Power-One inverter?

[Rob Beckers]

Veggie, the 48V cut-in is 3-phase AC? If so that would translate to roughly 68V DC. The MPPT window for the Aurora inverters runs from 50 to 580V DC. Their smallest is the PVI-3600, it's a 3.6kW inverter, used together with their PVI-4000-WIND-INTERFACE box that takes care of rectifying 3-phase AC and it provides a frequency signal for the inverter's MPPT mechanism. Pricing for that combo is around $2,600 (in Canadian dollars, it may be cheaper in the US since there are less borders and consequently shipping/duties involved). The inverter is UL1741/CSA 22.2 listed, ie. good to go for the US and Canada.

-RoB-