Quote:
Originally Posted by dcherba
determine the torque required by the motor. Assuming the motor is stalled use this current and the resistance to determine the total watts to hold this in place.
|
Determining the current using the motor's Kt from the motor curves will give you average current.
Attached is a simulation plot of the current waveform for a CIM driven by a Victor at 5% PWM*
The instantaneous current is shown in red. The average current is in aqua. The rms current is in green.
Power consumption should be computed using the rms current, which can be higher than the average current when using Victor controllers at lower PWM in stalled condition. In this case, the power consumption is 60% greater than the value computed using average current.
I suspect this condition is even more exaggerated in the smaller motors, but I don't have inductance specs for them. Has anyone measured the locked-rotor inductance of the Banebots or FP motors?
*note: this is based on CIM inductance of 200uH, which I was told but have not independently confirmed.