Voltage/Current Cut Off Thingy

Hey everybody so i have been a bit of a lurker lately not too many post but i have been here. So i was reading the thread about the turbine being too powerful and it got me thinking. i am going to get a 30 amp max charge controller. It will be fairly expensive and i dont want to blow it. I know adding resistance to the system will limit the current however that would not really solve my issue. is there some kind of part that will clamp off you current at a certain point but let it all through if it is under that amount. For instance if my turbine is outputting 0-29.9 amps they would all go through this part to the charge controller however when i reach 30 amps the part would only let 30 amps through as to protect my charge controller. like i said adding resistance would work but it would whack you even at low current. my hope is that i can have all of the current g through if it is outputting under 30 amps but limit the input to the charge controller to 30 amps in a situation where the turbine is outputting over 30 amps.

Thanks Fellas (And Lady Fellas if you want to be picky)
~Zac

Wind turbine power does Not go through a controller suited to wind power.

If you are looking at a solar controller, it will blow up far below 30A.

If you are looking at Wonder Controllers on ebay, look elsewhere.
G-