I'm trying to control the speed of a PMSM in the simulation software PSIM.
Now, I have learned that in a Synchronous Machine the steady-state speed is directly proportional to the frequency of the source, independently of the load (assuming it is in a supported range).
Therefore, I was hoping to be able to control the speed in a open-loop, by just changing the frequency using a inverter (and the voltage accordingly, to avoid flux saturation). But I have not been succesful and every article I've found so far uses Current Control to achieve speed control, which increases the complexity.
Is it not possible to control the speed of a PMSM without caring about the current?