What does the ω_r represent in the Mechanical System Equation provided in the Permanent Magnet Synchronous Machine

I am trying to better understand the Permanent Magnet Synchronous Machine function block however, I don't understand where ω_r comes from? How does it relate to ω_m? Any help is appreciated, Thanks in advance.

https://uk.mathworks.com/help/physmod/sps/powersys/ref/permanentmagnetsynchronousmachine.html

Answer 1

[Sergey Kasyanov]

Hello,

That is also mechanical speed because that is equation of mechanical speed. Maybe in the full system of equations of SM in SI units w_r may be defined as angular velocity of magnetical field (There are two different variable in common which is equal if SM have one pair of magnetic poles) but that description is not used in practical work.