wind powered battery charger circuit questions

[fwreed3]

So I am building a wind powered battery charger and I’m not sure of some of the parts I need for the circuit. I have the small wind turbine built with a Super Speed 9-18VDC Hobby Motor from Radio Shack. Next I am connecting the motor to the collector of an NPN transistor. The emitter of the transistor will connect to a fuse then a snubber diode then to the batteries (2 AA or AAA batteries). I am then connecting that to a PIC, which I still have to program, and the PIC will have a LCD output of the battery voltage. The PIC will also connect to the base of the transistor. Lastly I did test the wind turbine and it looks like I am getting a constant 9V out of the motor under controlled conditions. My question is this: what type of NPN transistor/fuse/snubber diode should I use? And would it be practical to add a capacitor to the circuit to give a more constant charge? Thanks

 

[audioguru]

A high wind will increase the RPM of the windmill and maybe tear it apart. Also then the output voltage and current will be much higher.

Real windmill generators have a heater that is connected as a load to slow down the windmill during a high wind. Then the generator motor will get hot so it must be big enough to dissipate its heat.

If your battery cells are Ni-MH then they need a constant current circuit to charge them and a circuit that detects that they are fully chearged then it shuts off the charging. Use a battery charger IC.