Controllability and Time-Variable Unilateral Networks

Controllability is a valuable characterizing property in the theory of linear systems. In this paper, conditions which involve only system coefficient matrices and a finite number of their derivatives are shown to be sufficient for the controllability of linear time-variable systems and are used to exhibit some interesting effects in particular time-variable systems. Application of controllability concepts to time-variable electrical networks is considered; in particular, it is shown how the sufficient conditions for controllability may be used to develop classes of unilateral networks composed of only linear, two-terminal elements. Examples of such networks with time-variable RC elements are given.