A methodology for the design of digital periodic controllers for simultaneous performance

The problem of finding a controller to achieve good levels of closed-loop performance for all the systems in a given set is addressed. An efficient two-step methodology to compute a digital linear periodic controller to solve this problem is presented. First, a linear periodic controller that stabilizes all systems is obtained. Second, the closed-loop performance of this controller is improved using are iterative linear-matrix-inequality (LMI) based algorithm.