I have modelled a large synchronous motor 28 MW 11 kV in simulink that is fed by a three-phase 11 kV grid. I am simulating startup effects of the motor during DOL start. The problem is that the field current I am getting is around 4 pu during the startup which is way too high. I have tried inputing a negative field voltage during the startup by taking the field current and multiplying by a gain factor of negative 2 - as seen in this example: https://se.mathworks.com/help/sps/ug/starting-a-synchronous-motor.html However, this doesn´t reduce the field current, and I am not able to insert any resistor as well, since the Vf port only takes in signals or constants (not electrical signals). Therefore, I am wondering if it´s possible to add a field resistor any other way?
I was thinking of changing my machine block to the simscape version (the blue one) salient pole model, but then I can´t connect mehanical loads to it (I believe).
My goal is to simulate the startup of the motor as an induction motor using damper windings and then apply field voltage excitation around 95-98% speed of synchronous speed. I understand that this requires some large currents going in the field windings, but 4 pu is too much.
