Realising a torque rod getting a PWM current signal and controlled with PID Controller

I am trying to develop a 3 axis magnetorquer on simulink. I wish to have a 3 axis control by giving desired RPY(Roll, Pitch and Yaw) values. This will be done by using a PID control block followed by a PWM block. But I am unclear as to how to integrate them.

Also it is unclear as to how to make a physical model of the orthogonal rods in simulink, so that when I give currents, the entire configuration rotates accordingly.