It depends what is limiting the output at the moment.
Can you tell us more about the generator, and the rectifiers etc?
Some alternators are current limited by their own inductance. You can add series capacitance, before the rectifiers, to compensate for the inductance, which will give you more current.
However.....
On a wind generator the speed is very variable and so the optimum capacitor varies a lot.
You may be limited by the power available from the wind anyhow.
and
The alternator may overheat if you get more current from it than it was designed to give.