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Understanding Results from "Experiments" (sweeps)

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gazlinux
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Understanding Results from "Experiments" (sweeps)

Hello everybody and thanks for such an outstanding project! 

I am a novice DIY making my first efoil and new VESC community.    

Recently, I configured and ran the three default "experiments" on my brushless sensorless motor (no load/on bench):

DUTY SWEEP - worked well and motor sounded great through the cycle ramp. 
CURRENT SWEEP - motor starts out but then 20% through the default sweep motor ramps to high rpm and sustains this high rpm through rest of cycle
RPM SWEEP - motor jerks hard, rattles hard and shakes and I must stop the test because...well I am afraid something is poorly misconfigured and need to avoid damage.

What settings might I check to better understand and fix the behavior of my motor when in current and rpm sweeps?  Fixing current sweep means configuring or determining how to smooth out the ramp so my motor can be controlled in current control mode (as of now, Its either off or quickly ramps to full speed).  And fixing rpm sweep means having it run smoothly in RPM control mode.  Sorry for my pedestrian terms, this is all new to me.     

Cheers from California!!

frank
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If you have no load, even a small current will make your motor spin to almost full RPM. In this case you need to load the propeller.

In RPM sweep you seam to have issues to start up the motor and it jerks. Do you have motor sensors or did you configure sensorless startup?

 

 

gazlinux
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Thank you Frank for helping me (and so many others) enter the wonderful world of VESC!

Regarding RPM mode startup motor jerk, I have no sensors on the motors and my BLDC Sensor Mode is set to Sensorless. I tried adjusting startup boost and in the PID zeroed out everything except speed and position Kp. Lots of settings so maybe I missed something...?

frank
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You can try  HFI or VSS for sensorless startup.