Alternator Field Winding Question

[doubledipsoon]

I have an older 12 volt battery-charging 1979 Sencenbaugh wind generator that I am testing. It has an 3 phase alternator with a field winding that must be excited, as opposed to the newer "permanent magnet" alternators. The manual says that 60 watts maximum should go to the field winding. According to theory, amps= watts over volts, so the amps to the field winding should be 60watts (the desired wattage to the field winding)/13.5 volts (battery bank at full charge). So the amps comes out to 4.4 amps. I just measured the Ohms off of the 2 field winding wires, and it came out to 6.5 Ohms, which allows only 30 watts to the field windings. So the big question is, how can I deliver 60 watts to my field winding? By the way, I won't be regulating the wattage to the field winding- I intend to keep 60 watts continually hooked up to the winding. I'm not an electrical engineer, I am self-taught, so I hope I'm thinking this out correctly. Thanks.

 

[Harald Kapp]

There are several methods for exciting an alternator.
You first have to ensure which one is suitable for your generator.

 

[skenn_ie]

You could use an adjustable boost converter to provide the exciter power.