Disturbance Observer-Based Predictive Functional Critical Control of a Table Drive System
This paper addresses a control system design for a table drive system based on the disturbance observer (DOB)-based predictive functional critical control (PFCC). To empower the previously developed DOB-based PFC to handle constraints on controlled outputs, we propose to take a critical control approach. To this end, we derive the transfer function representation of the PFC controller and yield a detailed design procedure. The effectiveness of the proposed method is confirmed through an experimental evaluation.
Perspectives on the principle of matching and the method of inequalities
The paper explains two general and complementary concepts of system design that have direct relevance to the theory and design of control systems: the principle of matching and the method of inequalities. One aim of the paper is to supplement, clarify and unify the ideas and explanations contained in previous publications. To this end, the essential ideas are presented in their simplest forms to make the paper also serve the purposes of an introduction and a review of the field. Another aim is to discuss the effects of the concepts on the foundations of the control theory, without neglecting the practical aspects of design.
Combined frequency and time domain technique for the design of compensators for non-linear feedback control systems
Computer based methods are developed for the analysis, synthesis and design of linear compensators for a wide class of single-loop non-linear feedback systems characterized by a separable non-linear element of any general multivalued form. Preliminary analysis is performed in the complex frequency domain applying approximate analytical methods to predict and quantify possible modes of limit cycle operation. Graphical displays are used to determine initial compensator structure which will ensure the avoidance of the critical region in this domain. Subsequently, a numerical synthesis procedure is applied to adjusting the compensator parameters to meet a set of additional time domain functional subject to specified system constraints and, if possible, the absence of autonomous limit-cycle operation.