Abstract
The purpose of this paper is to investigate the problem of designing a minimal order function observer with arbitrary poles which estimates (n-m-μ)-dimensional partial state for a continuous-time observable n-th order system with an m-dimensional output.
A generic condition to construct a function observer with arbitrary poles is reduced to a restrictive condition for left eigenvectors of a reduced order observer by use of the following result: a full order observer converges to a reduced order observer as some poles approach infinity in the left half complex plane. On the basis of the restrictive condition, in μ≤m minimal order of function observer with arbitrary poles is given, whereas in μ>m upper bounds of minimal order are given.
