Abstract
This paper presents a new insight into controllability for linear periodic continuous-time systems. A number of necessary and sufficient conditions for linear periodic systems to be controllable have been proposed in mutually different forms. However, it is common for these conditions to be described in terms of input coefficients and fundamental solution matrices or transition matrices of the systems. On the other hand, more convenient controllability criterions such as PBH test are available for linear time-invariant systems: the criterions can be described by system matrices in the state-space representations instead of fundamental solution matrices. The purpose of this paper is to derive a controllability criterion in terms of system matrices for linear periodic systems in parallel with the case of linear time-invariant systems. To be precise, this paper proves the existence of particular state-space representations where controllability can be checked directly through system matrices.
