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FOC detection....

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Roger Wolff
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FOC detection....

Hi, 

Somehow my hardware measures "R= 0.00". To try and figure out what is going on I'd like to run the lambda detection. But this is blocked due to the R=0.... 

How Do I get past this?

 

TechAUmNu
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If you want to test pwm just use the button to set a constant duty cycle with no motor connected. 

 

Roger Wolff
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There are two motors. The idea was to make the system work on one motor and then without changing the configuration move over to the second motor. With the motors being identical, that should work, right? That other motor is tucked "far away", is difficult to reach and impossible to allow it to turn freely.

Now we have realized that the second motor may have a different cable-length. And with 16mOhm measured resistance, and 2mOhm/m of wiring losses, a 1m difference in wire length will already contribute 12% of the motor resistance. So I would like to re-measure the resistance of the test motor, and possibly recalibrate the test motor. And we can have the vesc-based motor controller try to measure the in-system resistance once we switch to the other motor. 

TechAUmNu
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I normally will test a motor free running and then remeasure the R and I values with the load attached. The flux linkage doesn't tend to change.