I would like to calculate the actual power the motor connected to my ODrive is consuming.
For this purpose I multiply the Ibus variable (current_control_.Ibus) with vbus_voltage.
However I noticed this value was off when looking at the (voltage * current) my power supply was indicating.
I ignored it but came back to it when I was using a battery instead of a power supply. As a test I measured the DC current flowing form the battery to the ODrive with a Fluke clamp meter: the manual measurement resulted in 8.2A(DC)*45V = 369W, while ODrive’s Ibus*vbus_voltage resulted in only 70W (average, multiple samples).
As an extra test I applied 2A in current control, while manually blocking the motor. I put the Fluke (in DC mode) around one of the motor wires, while slowling rotating the motor until I got the maximum DC current. This was about 7-8A. So it seems the phase current measurement is wrongly scaled?
What could be the cause of this scaling error, and has anyone else experienced this?
I’m using a ODrive 3.5 48V board. The motor was in closed loop control.
Thanks in advance,