Self Excited Generator AVR

The self excited generator does not have a permanent magnet or external dc source for excitation but rather uses the residual magnetic field of the iron core to build up voltage in the exciter coil.

Since the current ratings match, you can use the AVR for the brush type generator. In principle it must work if the AVR is designed to operate on the resistance you mention.

You must follow the connections properly and also the polarity.

You must find out then AVR designed Minimum Load resistance. If this resistance value is less than the 14.5Ω of your existing field winding, then you might have a possible problem of not being able to reach the 6.25A for the full load. But you can have a go and try it without a risk of cooking it (the AVR).

If the AVR required load resistance is more than 14.5Ω, you can still run but the AVR efficiency will be lower than the designed value and might BURNout at full load.

Ideally, you want the AVR rated Resistance to be = to 14.5Ω (or lower but not too far away).