Byung-Moon Kwon

Fundamental limitations imposed by RHP poles and zeros in SISO systems

Establishes limitations on the impulse response of an LTI system based on the open-loop poles and zeros located in the convergence region of the closed-loop transfer function. Using the definition of Laplace transform, it is shown that time-domain integral constraints have to be satisfied by the impulse response of the SISO stable system and that the maximum value of impulse response has some lower bounds according to the achievable settling time of the system. Also, it shows the reason why it is very difficult to control the system with open-loop RHP (right half plane) poles or zeros using the unity-feedback scheme in the view of small impulse response. These results can be used to determine a priori whether desired design specifications axe achievable or not.

Fundamental limitations on the step response of SISO feedback systems

Abstract This paper proposes new fundamental limitations on the step response of the unity-feedback system based on its transfer function. Using the definition of Laplace transform, it is shown that time-domain integral equalities have to be satisfied by the step response of SISO (single-input, single-output) stable system, and shown that the maximum magnitude of its step response has some lower bounds with respect to the achievable settling time of the systems. It is also shown that the closed-loop system with open-loop RHP (right half plane) poles and/or zeros has some limitations in the unity-feedback control scheme. These results can be used to check in advance whether desired design specifications are achievable or not.

SOME LOWER BOUNDS ON THE IMPULSE RESPONSE OF SISO SYSTEMS

Abstract This paper establishes some lower bounds on the impulse response of SISO(single-input, single-output) stable systems imposed by zeros located in the convergence region of the system. In nonminimum phase systems, the other bounds are derived, which are more severe than that of minimum phase systems owing to RHP(right half plane) zeros. The lower bounds proposed in this paper show the trade-off relations between the maximum magnitude of the impulse response and the achievable settling time.

Robust H/sub /spl infin// FIR filtering for nonlinear time-varying systems

This paper investigates the robust H/sub /spl infin// filter with FIR (finite impulse response) structure for nonlinear discrete time-varying uncertain systems represented by the state-space model having parameter uncertainty.

Robust H/sub /spl infin// FIR filtering with sampled-data measurements

The problem of robust H/sub /spl infin// filter with FIR (finite impulse response) structure for linear continuous time-varying systems with sampled-data measurements is to be considered. It is assumed that the system is subject to real time-varying uncertainty which is represented by the state-space model having parameter uncertainty. The sampled-data system is represented by using piecewise continuous system with finite jumps. The robust H/sub /spl infin// FIR filter is derived by using the equivalence relationship between the FIR filter and the recursive filter, that would be guarantee a prescribed H/sub /spl infin// performance in the continuous-time context, irrespective of the parameter uncertainty and unknown initial states.