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I'm an EV owner and aircraft pilot and I've built/fly 2 aircraft. I have a new long-term project to build an electric launch sailplane. So while I can't dispute the crackpot claims, I will live.
A self-launch glider had exactly two speeds... taxi/cruise-sustain (50%) & full (takeoff). I don't really need an elegant brushed aluminum digital controller with fuzzballs, just two speeds (off, low and closed).
The first and simple answer is good old Ohms law of resistance. The target system is 120v, 40ah SkyEnergy cells, 5C continuous, 10C max. This is connected to a Warp7 motor, I want to get about 20kw static (~18kw in the air, higher RPM). I did my own math to size a $30 digikey ceramic resistor. Can anyone here do it too to check me, I really don't want a fire.
The second option might be to run a transformer to chop the voltage. I need someone who didn't take EE-for-dummies in college like me for this one, as I don't understand how the lower voltage won't just over-current the line and again... catch fire! Did I mention that pilots don't like fire!?
So regardless of the resistor or transformer (if that can work), I will connect two big fat contactors to an "off-low-high" 3-way toggle switch.
Thanks,
-Bruce
A self-launch glider had exactly two speeds... taxi/cruise-sustain (50%) & full (takeoff). I don't really need an elegant brushed aluminum digital controller with fuzzballs, just two speeds (off, low and closed).
The first and simple answer is good old Ohms law of resistance. The target system is 120v, 40ah SkyEnergy cells, 5C continuous, 10C max. This is connected to a Warp7 motor, I want to get about 20kw static (~18kw in the air, higher RPM). I did my own math to size a $30 digikey ceramic resistor. Can anyone here do it too to check me, I really don't want a fire.
The second option might be to run a transformer to chop the voltage. I need someone who didn't take EE-for-dummies in college like me for this one, as I don't understand how the lower voltage won't just over-current the line and again... catch fire! Did I mention that pilots don't like fire!?
So regardless of the resistor or transformer (if that can work), I will connect two big fat contactors to an "off-low-high" 3-way toggle switch.
Thanks,
-Bruce