Closed Loop Controller

[Smashroom]

Hello ,
I want to ask something about the closed loop controller. Which one is better ?

• Lower Torque Ripple (~ 25.7-27.2 Nm),but too much change on slip speed( -300-120rpm) and consequently electrical frequency (48-58 Hz) ?
• Higher Torque Ripple (~ 21.5-28.6 Nm), but more stable slip speed (60-65 rpm)and consequently more stable electrical frequency (48.9-49.7 Hz) ?

For the first case mechanical stress is less however electrical stress is much more . So after a while electronic side will explode. (My assumptions)

For the second case , there is not any electrical stress however mechanical stress is much more .

For both case motor is approached to desired speed .

What is your opinion about this problem ?

[ozank]

It's difficult to evaluate without looking the graphs, but I guess the second one is better, as the torque ripple does not increase that much?
What about the fluctuation in the rotor speed? Will you be able to hold it within reasonable limits?

[Smashroom]

Drive conducted for 1430 rpm desired speed . There is only small change or fluctuation in the rotor speed.