Week 07
Saturation and Anti-Windup
I use my PSIM report and PI calculation file to revisit the DC-motor model, cascaded current-speed loops, and field weakening.
What I connect in this unit
When voltage or current limiting separates commanded and actuator output, the integrator can keep accumulating error and wind up. Back calculation feeds the difference between saturated and unsaturated commands into the integrator so it returns toward the realizable output.
Concept map
- Voltage limit
- Current limit
- Integrator windup
- Back calculation
Technical anchor
A back-calculation form is x_i_dot = K_i e + K_aw(u_sat - u_raw); too little K_aw gives slow recovery, while too much adds an aggressive fast dynamic.
How I review it
Assume a large speed step that encounters voltage and current limits in sequence, then inspect whether raw command, saturated command, and integrator state reunite smoothly when limits clear.
Connection to the full course
Unit 7 of 12. Unit numbers follow the control structure in the saved design files and do not claim attendance weeks.