Series PIDA Controller Design for IPDT Processes

This paper discusses optimal design of the series proportional–integral–derivative–accelerative (PIDA) controller for integral-plus-dead-time (IPDT) plants. The article starts with disturbance reconstruction and compensation based on proportional-derivative-accelerative (PDA) stabilizing controllers. It shows that by introducing positive feedback a low-pass filter from (limited) output PDA controller, one gets observer (DOB) input disturbances. Thereby, DOB functionality is evaluating steady-state output. interpretation in full agreement results analysis setting its expanded PIDA version By using multiple real dominant pole (MRDP) method, it confirms time constant must be much longer than stabilized loop. also constrained MRDP leads to transient responses overshoots. Experimentally, such can shown as equivalent tuned parallel anti-windup connection conditional integration. Next, explores possibility removing overshoots process achieved tuning interchanging parameters transfer function, which was proven very effective case PID controller. modification only implemented approximately, when factorization numerator, gives complex conjugate zeros, will replaced double zero. Neglecting imaginary part specifying smaller approximative removal overshoots, but resulting dynamics not faster previously mentioned solutions. A significant improvement closed-loop performance finally calculated portrait method. points out terminologically incorrect designation proposed structure because does contain any explicit integral action. Instead, proposes more thorough revision controllers automatic reset output, do integrator, at same represent core most used industrial automation. In end, structures ensure higher usually preferred solutions action that, order respect control signal limitation, supplemented circuitry. excellent properties are demonstrated an example controlling thermal circle criterion absolute stability.