This Electric Power Steering (EPS) System design includes a MotorSolve generated Permanent Magnet Synchronous Machine (PMSM) model and a PWM Drive circuit. The drive includes a D-Q control algorithm, and uses space-vector modulation (SVM) to generate the digital PWM signals to the switches of the bridge.
The mechanical load model includes static and kinetic friction, a steering force that varies with rack displacement, as well as various mass, inertia, damping and spring/stiffness elements of the steering system. The steering torque, applied by the vehicle's driver, is assisted by torque from the motor scaled by the gear ratio. For the control, a non-linear gain profile is specified in the "torque_assist_table" function, and a lead-lag compensator is used to improve system stability.
In a companion version of this design, "EPS System with MotorSolve Generated PMSM Model and Ideal Drive", Clarke and Park Transform models are used with a continuous ideal voltage drive. This shows the ability to develop motor controls and drives at the abstract level and also at the circuit level.