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4 Quadrant DC Drive

0 votes

I am modelling a 4-Quadrant DC Drive. I managed to make it work for the First Quadrant. But the machine seems not to work in the third Quadrant. I will be glad if someone could help.

Thank you

asked Apr 25, 2022 by Estelle (12 points)

1 Answer

0 votes

The immediate issue here is the controller, not the machine model.  The current and speed are not regulated as you are intended due to fundamental control implementation errors.  For example, due to the SR Flip-flop in the modulation path you end up with an effectively fixed duty cycle of 0.9 @ 5 kHz.  The settings for the Relay block are to toggle at +/-1 A but the current reference is restricted to 0-0.2A meaning the current cannot be regulated within that window.

I would recommend systematically reviewing your controller to ensure each portion behaves as expected.


answered Apr 26, 2022 by Bryan Lieblick (1,887 points)