No load current vibration in Torque Control when I use KMS

[bansondou]

I have 2 question about Cureent control of KMS as below:

1. When I test torque control with KMS (no load condition and bare shaft). I find Q-Aixs and D-Aixs current has a big vibration as the picture.

2. I define Q-Aixs current is 0.20 A in torque control (as the below picture) . but in the above picture, Q-Aixs current reference is 0, and D-Aixs current reference is 0.17A. Why?

[linestream-adam]

Banson,

1. That is fairly common for motors running in torque control with no load.  I would only expect it to be perfectly flat if you had the motor at stall.

2. In the plot, it isn't showing the Q-axis reference.  It is plotting the speed controller output.  In torque mode, the Q-axis reference is user.output.drvCommand.statorRefCurrent.q (Q24, BASE_CURRENT).  Which should be exactly equal to the value you put in the GUI, stored in user.command.statorRefCurrent.q.

The D-axis reference is plotted against the right axis, which shows it is 0.