except if they put that same copper in the windings i doubt they’d need the heat pipe so i’m not convinced
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never tried that. Why?
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Discharge the battery / heat up the motors to test how fast the motors cool down. I don’t know how the phases in a motor work exactly but I’m guessing one or two of the phases were loaded disproportionately since I never let the wheels spin, and all the current was probably going into one/two phases.
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How quickly that happened? Was like suddenly or after you have been holding it for a while?
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Still wondering how foc works as it supposedly has all three phases powered. Waiting for someone on a forum to break it down for me. Surely have to get the back emf. If all phases powered at same time I’d think would be a much better motor.
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the foc torque nm = KT * 1.5 * (motor current or peak current per phase / sqrt(2))
so the ((copper loss per phase * 3) + (torque * rad/sec) = electrical wattage
KT = 60 / (2 * pi * kv)
copper loss per phase watts = (line to line resistance ohms / 2) * (motor current / sqrt(2))^2
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Doing bldc and foc tests show very similar kv and therefore Kt. It seems like ur saying the Kt would be 1.5 higher in foc
KT is tested in BLDC, but the torque in FOC is 1.5 * KT * “(motor current / sqrt(2))” = torque NM
motor current FOC = RMS current per phase * sqrt(2)
The kv can be gotten in either bldc or foc and could get a Kt from either. They’ve very close
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no the kv is tested in bldc at 100% duty at 0 motor current (faster than the motor spins on its own because the no load rpm is also the rpm of the motor when the peak back emf voltage produced by the motor equals the battery voltage)… the max rpm in foc is lower
at true no load speed in bldc, the back emf v produced by the motor equals the battery voltage, which is why there is 0 motor current and also why the motor can’t spin faster
in foc, the motor only sees the battery voltage at the peak of the sine waves, but in bldc it sees it the whole time at 100% duty, so foc spins slower but the KV is the same for both
the KT = 60 / (2 * pi *kv)
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To truly know the kv you spin the motor manually and get the voltage. Only way to get zero current. What that has to do with how foc works I don’t see
From the little I understand the three phases are powered and the voltages in two of the phases are half the third.
Makes sense foc would run cooler at highest torque as it’s one phase at full amperage and two at half, so one tooth saturates vs in bldc it’s two teeth at same high magnetic field. The same torque production in foc but using more teeth. Maybe. Where’s a dyno n thermometer
right spinning the motor to get the back emf voltage gives the same voltage/kv measurement whether you later spin it with bldc or foc, but the motor’s no load speed will be slower with foc
they’re all sinusoidal current waveform out of phase by 120 deg
it is almost always not “one at full and 2 at half”, but for the same torque the total copper losses are less with foc
^look at the bottom section of this pic for an foc current plot
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how do people buy DD’s theyre like 900$
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with money, about $999 for AWD
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You know what they say, $20 is $20 eventually you have $900. Also skipping everything in between saves some money 
…j/k belt folk
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Look into SPC wire if you really want cooler temps on DD.
You’ll need Areospace/mil spec 3 conductors twisted and normally a second sheild included with outter jacket.
if you replace just your phase leads from motor controler to motor you’ll notice significant gains.
It’s 1 micron thick silver coating. That’s barely anything. Maybe at super high frequency with skin effect be a benefit but we don’t run at those frequencies
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