Open flexible P-controller design

The paper represents first part of two contributions dealing with simplified modular design of constrained P and disturbance observer (DO) based PI control with different filtering properties illustrated by example of speed servo control. This first part is devoted to analysis of the core structure of the P controller tuned for different types of nonmodelled or filter dynamics. Openness of the approach means that for approximating additional dynamics of the P-controller structure different filters may be used without necessity to repeat in the nominal case analysis of the optimal and critical tuning. By simpler means, flexible approach enabling to fit requirements of particular loop and simultaneously offering reasonably better performance than the traditional controller design based on Luenberger disturbance observer for reconstruction of the velocity signal is proposed. Achieved performance is evaluated by newly introduced measures for deviations from monotonic and one-pulse shapes of transients typical for control of plants with dominant 1st order dynamics.