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measuring frequency response of motor current control loop



I am new to motor control.( I do have 20 year experience in dc dc converter design.) I am trying to figure out how to measure and record the frequency response of the motor controller. Most of the ap notes I see use time domain techniques to tune a PID controller.

I would like to be able to measure the open loop and closed loop frequency response of the current loop and speed loop.

I need to sum a small perturbation signal into the Iq or Id reference command and then observe the Iq or Id signal. I am thinking this could be done using software.

I would like to output these values through a serial port, SPI or I2C,  and  then D to A convert them and then feed them to a frequency response analyzer which would then generate a bode plot.

Has anyone tried this? Is it doable?