I am not sure what you are really trying to do.
Once the batteries are fully charged it may make sense to shut the wind turbine down for a while, but as a means of charge control for the final stages of battery charging this repeated on /off operation at low frequency is not a desperately good method and will not be as effective as a conventional dump controller using pwm.
Whether or not you can actually stop the machine depends on the alternator characteristics. Not all machines will stop with a direct short, and trying it on one that has an under powered alternator will overheat it or burn it out.
If it is capable of stopping from any wind speed with a short then you can do it and you can use the series resistors to make the stop more gentle .
If you are looking at this as a means of control to avoid furling then I really don't like it and in high winds it will get away to the point that you will have to use a direct short to stop it as there may not be time to go through the resistor steps each time. The larger the machine the less practical it becomes.
There is an Australian charge control kit that brakes the mill in a similar way to a charge controller for solar but I really don't like the idea. It may work at 500W but again it may have long term ill effects on the blades and the alternator.
Flux