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[Curt]

That and the amount of, torque and power (and therefore acceleration), per degree of throttle rotation.

I think the speculation is that that should not matter, only cruising speed. E.g., the same number of Wh should be required to go from 0 to 60 whether it's done in 4 seconds or 8 seconds, right? From E=(1/2)mv^2.

[BrianTRice@gmail.com]

That and the amount of, torque and power (and therefore acceleration), per degree of throttle rotation.

I think the speculation is that that should not matter, only cruising speed. E.g., the same number of Wh should be required to go from 0 to 60 whether it's done in 4 seconds or 8 seconds, right? From E=(1/2)mv^2.

He's saying that the mode (Eco vs Sport) changes the amount of current / torque delivered per physical position of the throttle.

Separately, for a given amount of current / torque delivery, the energy expended to get to cruising speed varies let's say negligibly.

BUT there's a fun factor to throw in:
- For a given amount of current / torque requested from the throttle,
- The battery voltage will sag by a proportional amount because of internal resistance.
- This will then subtly effect the power delivery in the same manner that operating at a lower SoC will.
- This might also be less efficient generally.

It's more or less negligible, but the point is that it helps with battery power delivery efficiency to smooth out or minimize fluctuations in throttle usage.

I've run tests using a live data logger (the third-party mobile app for Android that Apple's policies make unworkable on iOS) to watch current, voltage, etc. on a pretty high sample rate to understand the effect of the throttle on overall electric power delivery.

[Doug S]

BUT there's a fun factor to throw in:
- For a given amount of current / torque requested from the throttle,
- The battery voltage will sag by a proportional amount because of internal resistance.
- This will then subtly effect the power delivery in the same manner that operating at a lower SoC will.
- This might also be less efficient generally.

Yes, it's true that the efficiency of the electric drivetrain suffers SLIGHTLY at higher throttle openings. Also IGBTs, MOSFETs or any power switching device will have slightly higher voltage drop at higher current draw, contributing another little bit to efficiency loss -- not to mention the voltage drop in the wiring itself. But it's nothing like the toilet-flushing effect when you open the throttle on an ICE.

I've run tests using a live data logger (the third-party mobile app for Android that Apple's policies make unworkable on iOS) to watch current, voltage, etc. on a pretty high sample rate to understand the effect of the throttle on overall electric power delivery.

I'd love to see your data. I'm confident I'm correct but it would be very nice to see numbers to prove my point.

[BrianTRice@gmail.com]

I'm not saying the controller / power switching is less efficient because of the voltage drop. I'm saying that the voltage drops and you need to draw more current to supply the requested amount of power. Any losses I'm mentioning are from internal resistance which heats the battery a bit.

And I agree it's absolutely nothing like what happens with a literal throttle operating an ICE powertrain. The largest battery one can equip on a Zero is 18kWh max / 15.8 kWh usable which is equivalent to a half gallon of gasoline, and we're basically hypermiling out of that with almost all the losses due to drag, then rolling resistance, and then finally internal inefficiencies.

I'm not sure that the data dumped will be very useful, unfortunately, since throttle position isn't recorded. But I do know how much voltage droops depending on the output current. It's substantial enough that I can see why the dash doesn't show it - our skittish owner population would freak out.