Wow, that's a huge savings over the NdFeb's. We bought ours quite awhile a ago (.75" x 1.50" x 3.00"), but I'm thinking they were ~$20-22/ea.
Oh, for sure. It does take more mags with the ferrites because, for example, I'm using a 16 pole gen compared to normally using a 12 pole gen with a ~10 foot turbine. Plus I'm using gearing to get the voltage, where with neos it wouldn't be really worth putting gearing on it. So there are some basic design differences, but the ferrites are more fun and more challenging and I can buy enough magnets to build two turbines for only ~$120.
That's our plan as well. I'm going to move our diversion load over to the Aux 2 (PWW relay)
I'm not totally sold on going to the extent of using PWM on Aux 2. I think I'm going to prefer to use a regular old two pole contactor and just slam it shut with the output from Aux 1 to "clip". I look at the "clipping" as an emergency thing to keep the voltage from going over the 150 volt limit, and not necessarily trying to regulate it at the clip point with PWM. I'm going to run the gen at around 100 volts at full output on this turbine, and that will only require about 27-28 amps at the top limit of what the controller will handle for output amps on a 24 volt system (not figuring losses in the controller and so on).
Since I'm well under the voltage limit with the turbine loaded, if it gets to ~140 volt then that means I got a problem someplace - the machine didn't furl, the breaker on the Controller blew and unloaded the turbine, or something similar. This should never happen. And if it does, at that point, I'm considering just tripping a latching contactor or relay to throw a 3 kW load on the turbine, which won't shut it down but it'll severely brake it even in strong winds. Once it trips, it requires manual intervention from me to fix the problem and let it go again.
That's why I said it's similar to Ryan's setup, but not exactly the same. Ryan's setup with the Teledyne Triac attempts to regulate the voltage at the upper or "clip" limit. I think his setup is better if you design your turbine to run right at the raw edge of the over-voltage limit of the controller. I'm not doing that, but instead "clamping" the voltage down on the turbine when it reaches around 2 kW output to start dropping the TSR of the rotor, reduce the power efficiency of the generator a bit, and limit the top speed of the rotor to about 400 rpm.
It would be easy enough to let it spin and run the voltage up to 140. But I don't want a MPPT "Buzz Bomb" on the tower. I'm not all that interested in getting big high wind numbers - more interested in tuning for the midrange So my power curve for the controller cuts the turbine in at 100 rpm with the rotor running at ~6 TSR, then ramps the voltage up very quickly right off the bottom to keep the rotor at 6 TSR up to about 20 mph wind speed. It might sound stupid to cut a 10 foot rotor in at only 100 rpm, but with the Classic you can do it with no danger of putting your turbine into "stall" - and you don't have to overspeed it to 8.5 TSR at cut-in to make the turbine work properly.
Yes, I have my distrust of electronics too. But the more I tested and learned about how the Classic works, the more I like it. It took me a long time to even convince myself to try it, and I came up with every excuse I could think of why it wouldn't be any good. But, frankly, this is no cheap Chinese controller slammed out with substandard components in it. This thing is built like a tank and it's pretty obvious boB didn't cut any corners on designing it. So I'm learning to trust it because it's the coolest thing I've ever played with
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Chris