Variable Speed Driver for Induction Motors - Constant V/Hz Control

Hello everybody.

I am trying to implement what should be a "simple" control for induction motors. I attach the *.mdl file in case you want to take a look.

I am following the next scheme [1]:

Instead of ωr in the second "sum" block, I am using ωr*.

I don't know why, when the speed approaches the reference, I get an oscillation that brings my model to instability. I find this very strange since I do not implement any transients or anything like that.

Thank you all!

[1] Bose, Bimal K. 2002. “Modern Power Electronics and AC Drives.” Prentice-Hall. https://doi.org/10.1016/S0927-0248(96)00085-2.

Answer 1

[Sabin]

Simscape Electrical provides a block implementing Scalar Control:

https://www.mathworks.com/help/sps/ref/inductionmachinescalarcontrol.html

For an example about how to use it to control the induction motor:

https://www.mathworks.com/help/sps/ug/asynchronous-machine-scalar-control.html