There are many, many examples of AF burnouts. A lot of them though were direct-ties with little or no place for load once the batteries were full. I'll still suffer some lumps the hard way, like other before me, but why invite trouble?
Yeah, but most of those were/are amateur built and designed too. And a lot of installations where things aren't matched in wiring resistance, stator resistance, blades, etc.. It's not the fault of the design.
I never really posted much on these turbines, as it seemed turbine building had gone out of style, and most of my designs ended up being too controversial because they went against everything the homebrew books said. So I eventually just quit posting the details on them and moved it all to my own website.
These are 3.5 meter machines and they produce 3 kW continuous @ 12 m/s wind speed on a 48V system. They are over twice the overall efficiency of a AWP3.6 or 3.7. And you cannot burn one of these out. They will free-spin at 20 m/s wind speed at over 1,000 rpm with no problem (although they are noisy when doing that). They can run fully shorted in 20 m/s wind with no problem, and in fact that that is method I use to keep them online in high winds, running them shorted with a mechanically engaged voltage clipper, with the clipper keeping the power output and voltage to a level that the Classic 150 controller can handle. They can also be wound for any voltage you like - this stator is a 180V unit:
And they actually will furl in very high winds running unloaded, just like a Bergey Excel will. Although they will furl earlier if the machine is fully loaded and producing full power:
Just to show you that there is a little more advanced design in axial turbines than what is shown in the homebrew books. I've been building them for years, and departed from the trailer hub turbines after the first one I ever built because they were problematic and not too durable. You'll probably notice that my design sort of follows Gordon Proven's design, except mine is upwind with side furling while Gordon's machines were downwind with spring loaded blade feathering.
Regardless, these machines have proven to be extremely durable - can't break one. So don't fault or discount the axial flux generator as being "inferior" somehow. You run them at high enough voltage, just like the AWP's radial, you can't break it or burn it because the more copper you put in the stator, the higher the reactance and self limiting becomes as it reaches full power. The axial designs with those big round magnets on 9 tiny little coils, then strap 10 foot blades to it should have "burn out" stamped right on them. It is a flawed design from the word "go". But it is not the axial's fault.