Self-tuning IMC-PID control with interval gain and phase margins assignment

The idea of pole-region assignment is extended to interval gain and phase margin assignment. The internal model control proportional-integral-derivative (IMC-PID) design is examined from the frequency domain point of view. Equations for typical frequency domain specifications such as gain margin, phase margin and bandwidth are derived for the IMC-PID design. The gain and phase margins are monitored in real time and a self-tuning controller with interval gain and phase margin assignment is proposed. An implementation example in the laboratory is also given.