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gblass1

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Joined: 16/09/2009
Location: United States
Posts: 11

Posted: 12:44pm 16 Sep 2009

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Hi All

I just found this forum a few days ago and have been reading and trying to digest all the great info here.

A little about me.....I have a 5.2kw Grid Tied PV system on my house that generates 100% of my power for 4-6 months of the year. During the fall and winter months my solar output drops off but the wind picks up. My plan is to build a wind generator to supplement my solar and ultimately have it grid tied like the solar.

I have a Reliance Electric DC servo motor Model E728 P/N 0728-06-029 that I would like to use for my first project. I have searched google and can not get the specs on this motor to determine if it is suitable for a wind generator. So I hooked it up to my milling machine and recorded the Volts at a given RPM. Is it possible to determine how many amps or watts this will produce ? Below is the info I have.

RPM Volts DC
180 10
200 12
280 15
360 20
450 25
1000 50
1500 75
1800 100
2400 125

Gizmo

Admin Group

Joined: 05/06/2004
Location: Australia
Posts: 5119

Posted: 12:58pm 16 Sep 2009

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Hi gblass1

What is your system voltage?

It looks like that motor would work OK for a 12v system, and might work for a 24v system. A 48v system would need the windmill running at over 1000RPM, too high for a direct drive.

Glenn

The best time to plant a tree was twenty years ago, the second best time is right now.
JAQ

gblass1

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Joined: 16/09/2009
Location: United States
Posts: 11

Posted: 01:07pm 16 Sep 2009

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Hi Glenn

Thanks for the reply. Please excuse my ignorance ( I'm a mechanical guy and not good with electrical ) but I'm not sure what you mean by system voltage. If your referring to 12 volt or 24 volt I haven't decided which way to go. If you were referring to my PV system it typically runs at 275-300 volts DC into the inverter.

My original plan was to run the wind generator output directly into a grid tie inverter. But from what I have been reading on this forum I'm not sure if that will be possible. It seems like I will have to run the output to a small battery bank then into an inverter.

Thanks

George

gblass1

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Joined: 16/09/2009
Location: United States
Posts: 11

Posted: 08:11pm 16 Sep 2009

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I was able to track down the motor specs, here they are

Max Voltage = 120 DC
Max Speed No Load = 3000
Max Peak Current = 38.0 Amps
Max Cont Current = 7.2 Amps
Max Terminal Resistance = 1.26-2.17 OHMS @ 4 Amps
Max Peak Torque = 3000 OZ-IN

GWatPE

Senior Member

Joined: 01/09/2006
Location: Australia
Posts: 2127

Posted: 11:24pm 16 Sep 2009

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gblass1 said .....I have a 5.2kw Grid Tied PV system on my house that generates 100% of my power for 4-6 months of the year. During the fall and winter months my solar output drops off but the wind picks up. My plan is to build a wind generator to supplement my solar and ultimately have it grid tied like the solar.

This is a very large solar panel for a domestic home, and it is not enough!!

I must admit that in some places, heavy rain all day, that not much power will be produced.

You will need a much bigger windmill than the one you plan to build with the servo motor. With good winds, this little motor could produce 0.5-1.5 kWhr per day. Compare this with a good day with the solar of 20-30kWhr.

One extra solar panel[170W] could probably produce more power than this windmill in a year.

A factory made grid connected windmill might be a better option than batteries and associated hardware.

If you really want to make a windmill, as a hobby with benefits, then OK.

You need a good windy site all year to justify a windmill economically.

Gordon.

become more energy aware

gblass1

Newbie

Joined: 16/09/2009
Location: United States
Posts: 11

Posted: 12:51am 17 Sep 2009

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Gordon thanks for the reply. This project would kind of be a hobby / experiment so if it does not produce a huge amount of power that's ok. Adding more solar panels would be more expensive up front and my inverter is maxed out with 24 panels. Also in the winter the solar drops way off but the wind up on the ridge I live on is quite consistent 24/7.

Another option that I thought might produce more power is using a Fisher & Paykel motor. I was looking at www.randysworkshop.com and it looks like he has a nice kit for this motor.

George

Bryan1

Guru

Joined: 22/02/2006
Location: Australia
Posts: 1464

Posted: 11:08am 17 Sep 2009

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Hi George,
First welcome to the forum mate

Now you have said your a mechanical guy so whynot consider a 3 phase motor conversion or a dual axial flux genny. Do some research and either can be used for grid tie. Some members on other forums have done this successfully.

One of our treasured members has done a decogging tutorial for motor conversions but it went above the pdf limit as I did try and post it here for you.

In the electro-tech forum in the RE forum there is a guy who maybe able to help, just post your question there and see, if you like I can PM him as I am a moderator there.

Now do you have a RE system setup or are you just supplementing the PV off your bill ?

Cheers Bryan

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