Motor doesn't stop [SOLVED]

[davidmichelman]

Hi all

I recently got my gen2 Leaf motor spinning with a Zombieverter (hooray!). But if I spin the motor up past ~200 rpm, it continues to accelerate after I completely let off the throttle. See this video at 0:32, you can hear the pitch of the motor increase steadily even though throttle input is zero, and the attached log file shows speed steadily increase too.

I'm puzzled because I logged potnom during that video, and potnom is clearly zero while the motor speed is increasing. I don't see any logic between here and here which could send a non-zero torque value to the inverter if potnom==0. My only idea is maybe potnom's value is between 0 and 0.0045 and thus being rounded down to zero when displayed?

Question: is this a known phenomenon? Is there a known fix?

[m.art.y]

Is motor loaded? Unloaded motor will keep spinning since there is no regen yet.

[davidmichelman]

The motor speed increases, not decreases. The motor is unloaded, so I agree, it shouldn't stop immediately. But I also expect speed to not increase when the accelerator pedal is not pressed.

Here's a plot of the log file attached to the original post, you can see speed increasing even though potnom is zero (I cut T15 around sample 89, that's why the motor eventually stops)

[tom91]

A leaf motor will keep spinning up with no load. It is designed to work in car so there is compensation to allow it to coast, now when you remove the car load and drivetrain drag the motor just ramps up speed as it does not know the car is missing.

[Alibro]

I had the same issue with a gen 1 leaf motor. Put a load on it and it will be fine. I found with the transmission bolted on it was just enough load.