A Comprehensive Study of Time Moments and Markov Parameters in System Reduction

摘要

Time moments and Markov parameters play two important roles in the simplification of large-scale system. First role plays in the matching of steady-state responses of the full order and reduced order plants; for this, the matching of their initial few time moments are required. The matching of transient responses between the complete order and lower order systems is the second role of the time moments and Markov parameters. For the second role, the Markov parameters of the actual order and lower order plants must be matched. In this contribution, it is shown that the time moments are not only responsible for the matching of static responses but also for the matching of transient responses. For better understanding of the contribution of the time moments and Markov parameters, popular examples are taken from literature and in each examples, proposed concepts are explained. A new system diminution technique is also proposed which may be applicable when the Pade approximation methodology fails. The process of obtaining reduced plant by this method is based on matching of Markov parameters in place of time moments matching.