Tuning of a filtered pole assignment controller for an integral plant

Abstract

The paper deals with an optimal filter tuning for a filtered PD control (FPD) with a specified tracking properties. Within a simplified modular design [1]-[4], in a nominal case, the filters required for a FPD controller implementation and a noise attenuation may be generalized to several augmented situations without necessity to repeat analysis of its optimal and critical tuning. The spectrum of possible situations includes loops with a disturbance observer based integral action, loops with a dynamical feedforward control and loops with a reference models applicable also to systems with a long dead time. In the tuning analysis, the traditional analytical method as the parameter space method [5], or the triple real dominant pole method [2] are combined with the numerical performance portrait method [1], [6]. A loop performance is evaluated by newly introduced measures for deviations from monotonic and two-pulse shapes of transients typical for control of plants with dominant 2nd order dynamics. The analysis shows that for a broad class of situations, a simplified design derived for a double integrator gives acceptable results also for 2nd order integral systems with one stable/unstable mode.