You are here

VESC efficency in position vs speed mode

3 posts / 0 new
Last post
vadimz
Offline
Last seen: 1 year 7 months ago
Joined: 2018-08-29 17:30
Posts: 17
VESC efficency in position vs speed mode

Hi,

Looking for any tips how to approach debugging the following situation:

VESC is controlling a direct drive winch motor that should lift a load. There is a magnetic 5047 encoder.  Motor detection and encoder initialization complete successfully. Idle operation in both position control and speed control mode looks correct.

With the load attached, in position control (position hold) mode the operation look correct - the current is roughly proportional to the load and is close enough to theoretical value ( Torque / Kt )

In speed control mode however, the current shoots up to roughly 6 times the value is hold mode (even at very low speeds where the added power due to rising the load is negligible).

 

Tweaking the PID values in the speed control section seems to have no effect. Any suggestions where to look next ?

vadimz
Offline
Last seen: 1 year 7 months ago
Joined: 2018-08-29 17:30
Posts: 17

Solved.
Embarrassingly, it turned out to have nothing to do with control. The sole reason for the discrepancy was mechanical friction in the system.

Elwin
Offline
Last seen: 1 month 1 week ago
VESC Free
Joined: 2021-09-30 16:41
Posts: 76

Nothing to be embarrassed about, and very good that you mentioned the cause here!