Synthesis and analysis of digital multiple repetitive control systems

Proposes the so-called digital 'multiple' repetitive control systems which can regulate efficiently 'multiple repetitive errors' which contain multiple dominant fundamental frequencies and their harmonics. Our multiple repetitive controller has not only a very simple structure but also such advantages as smaller memory requirement and faster error convergence speed than the conventional 'single' repetitive controller. The paper also presents a robust stability condition and an error convergence condition for our multiple repetitive control systems in a mathematically rigorous way. The performance of our multiple repetitive control system is demonstrated through simulations.