title: On computation of stabilizing loop gain and delay ranges for bi-proper delay systems.
abstract: A graphical method for exactly computing the stabilizing loop gain and delay ranges was proposed [Le BN, Wang Q-G, Lee T-H. Development of D-decomposition method for computing stabilizing gain ranges for general delay systems. J Process Control 2012] for a strictly proper process by determining the boundary functions which may change system׳s stability. A bi-proper process is rare but causes great complications for the method, due to the new phenomena that do not exist for a strictly proper process, such as a non-zero gain at infinity frequency, which may cause infinite intersections of boundary functions within a finite delay range. This paper addresses such a kind of processes and develops a general method that can produce the exact and complete set of the loop gain and delay for closed-loop stabilization, which is hard to find with analytical methods.
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 119260 Singapore.
authors.forename: Binh Nguyen
authors.initials: BN
authors.lastname: Le
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 119260 Singapore. Electronic address: elewqg@nus.edu.sg.
authors.forename: Qing-Guo
authors.initials: QG
authors.lastname: Wang
authors.affiliation: Department of Electrical and Computer Engineering, National University of Singapore, 119260 Singapore.
authors.forename: Tong Heng
authors.initials: TH
authors.lastname: Lee
authors.affiliation: School of Information Science and Engineering, National Huaqiao University, Xiamen 361021, China.
authors.forename: Zhuoyun
authors.initials: Z
authors.lastname: Nie
keywords: Bi-proper process; Delays; Stability robustness; Stabilization; Stabilizing parameter ranges