Higher Order PD and Ipd Controller Tuning

This paper deals with tuning of proportional-derivative (PD) and “intelligent” proportional-derivative (iPD) controller for the double integrator plus dead time (DIPDT) system. iPD corresponds to a PD controller augmented with a disturbance-observer based integral (I) action based on finite impulse response (FIR) filter. Since noise reduction requires working with as short sampling period as possible, the design of controllers is appropriate to implement in the continuous-time domain with a suitable discretization. In this way, when the noise attenuation filters are approximated by an equivalent dead time added to the plant dead time, stabilizing controllers with higher order output derivatives may be introduced simply and without excessive noise-induced control effort. Together with filtration of the reconstructed disturbance it significantly improves the overall loop performance.