On Padé approximations, quadratic stability and discretization of switched linear systems
نویسندگان
چکیده
In this note we consider the stability preserving properties of diagonal Padé approximations to the matrix exponential. We show that while diagonal Padé approximations preserve quadratic stability when going from continuous-time to discrete-time, the converse is not true. We discuss the implications of this result for discretizing switched linear systems. We also show that for continuous-time switched systems which are exponentially stable, but not quadratically stable, a Padé approximation may not preserve stability.
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ورودعنوان ژورنال:
- Systems & Control Letters
دوره 60 شماره
صفحات -
تاریخ انتشار 2011