PID control of integrating systems using Multiple Dominant Poleplacement method

Simple tuning rules for proportional-integral-derivative (PID) controller are proposed for Pure Integrating Plus Time Delay systems (PIPTD), Double Integrating Plus Time Delay systems (DIPTD) and stable/unstable First Order Plus Time Delay Integrating systems (FOPTDI) based on Multiple Dominant Poleplacement (MDP) method. The main advantage of the method is that there is no time delay approximation for deriving PID settings. Tuning rules for PIPTD and DIPTD systems are given as a function of tuning parameter, and tuning parameter can be selected based on desired level of robustness (maximum magnitude of the sensitivity function, Ms). Tuning rules for FOPTDI system are given as a function of ratio of time delay to the process time constant for Ms=2. Simulation on various transfer function models and on non-linear model equations of CSTR carrying out an exothermic reaction shows the effectiveness of the proposed method in terms of Integral Absolute Error (IAE), Total Variation (TV), Overshoot (OS) and Ms. (c) 2015 Curtin University of Technology and John Wiley & Sons, Ltd.