Partial right eigenstructure assignment based design of robust damping controller

Abstract

The paper presents the design of an output feedback based centralized, damping controller using partial right eigenstructure assignment technique. The algorithm exploits the extra degrees of freedom provided by multi-input-multi-output (MIMO) systems in partially assigning a few, selected eigenvectors in addition to corresponding eigenvalues. Singular value decomposition (SVD) is used for determining the basis vectors for the achievable closed-loop eigenvectors. A derivativefree, direct search optimization technique has been used to solve the controller design problem. Robustness of the damping of inter-area modes to operating point changes is achieved by incorporating multiple models of the system in the optimization problem. The designed controller provides a supplemtary signal to voltage reference of a static VAr compensator (SVC). Remote feedback signals have been utilized and feedback signal selection is based on the input/output controllability metric. An algorithm explaining the framework and the results of its implementation on the IEEE 68 bus system has been provided. The results show the effectiveness of the controller in exploiting the eigenstructure of the system for damping inter-area oscillations.