The advantages of using FOC to control AC motors include:- Torque and flux controlled directly and separately
- Accurate transient and steady-state management
- Similar performance compared to DC motors
The Controls subsystem contains all four PI controllers. The outer-loop speed PI
controller regulates the speed of the motor. The outer-loop flux PI controller regulates the
flux of stator. The two inner-loop PI controllers control the d-axis and q-axis currents
separately. The command from the outer-loop speed PI controller directly feeds to the q-
axis to control torque. The command for the d-axis is nonzero for ASM and is a result of
the outer-loop flux PI controller.The existing PI controllers have the following gains:- Speed PI controller has gains of P = 65.47 and I = 3134.24.
- Flux PI controller has gains of P = 52.22 and I = 2790.51.
- D-axis PI controller has gains of P = 1.08 and I = 207.58.
- Q-axis PI controller has gains of P = 1.08 and I = 210.02.
The controller gains are stored in a Data Store Memory block and provided externally to
each PID block. When the tuning process for a controller is complete, the new tuned gains8 PID Autotuning