Authors: Mohamed Ayman; Mahmoud Soliman
Addresses: Faculty of Engineering (Shoubra), Electrical Engineering Department, Benha University, 108 Shoubra St., P.O. Box 11241 Cairo, Egypt ' Faculty of Engineering (Shoubra), Electrical Engineering Department, Benha University, 108 Shoubra St., P.O. Box 11241 Cairo, Egypt
Abstract: In this paper, the synthesis of robust three-parameter power system stabilisers (PSSs) is presented. Graphical characterisation of the set of stabilising PSSs is carried out using D-decomposition. Dynamic model of single-machine infinite-bus system (SMIB) is considered to accomplish the design. D-decomposition is extended to consider D-stability where D refers to a pre-specified damping cone in the open left half of the complex plane to enhance time-domain specifications. Pole clustering in a damping cone is inferred by enforcing Hurwitz stability of a complex polynomial accounting for the geometry of such cone. Parametric uncertainties of the model are captured by an interval polynomial. Hence, performance enhancement calls for Hurwitz stability of a complex interval polynomial. The latter is tackled by the complex version of Kharitonov's theorem. A less-conservative and computationally effective approach is concluded from the geometry of the stability region. Simulation results affirm robust stability and performance over a wide range of operating points.
Keywords: PSS design; robust control; D-decomposition; interval polynomial; Kharitonov's theorem; complex polynomials.
International Journal of Modelling, Identification and Control, 2020 Vol.34 No.3, pp.197 - 207
Received: 02 Sep 2019
Accepted: 12 Feb 2020
Published online: 30 Nov 2020 *