Other Parts Discussed in Thread: DRV8305, MOTORWARE
We have two pairs of LAUNCH XL 28027 + BOOSTXL DRV8305 + Motorware lab 05 speed_control and two identical motors.
Both kits running the same software.
But with one motor both kits run the motor at half speed compared to the other motor.
If we swap the motors the problem follows the motor to the other kit.
We can hear that the motor is running at half the speed, we cannot measure it mechanically because of inaccessibility to the motor axis,
But we have HALs on the motor (not using them for speed control because we are running FOC) and we have connected oscilloscope
via a low pass filter to one of the phases so we can observe the waveforms going to the motor.
Both the HAL signal and the phase waveform confirm that electrically the motor
is running at DIFFERENT speed, depending on the motor.
When we command 1000 rpm on lab_05 the electrical commutation frequency is either 333 Hz or 166 Hz depending on the motor!
How is that possible??
How can the software 'know' that it is running a different motor and alter its behaviour?
Even if the motors were somehow defective or of different type by some strange assembly error, how could this be?
I get it that if the the two motors had different number of poles (it is a two pole motor) then the physical rpm would be different,
but we are observing both the electrical phases and the HAL signals which tell the same story, the other motor runs at half speed...?!?!