Optimizing power system wide-area damping controllers under communication time delays and model reduction errors

This paper tackles two pivotal challenges within Lyapunov-functional-based approaches to analyze and design power system damping control amidst communication time delays. The first challenge addresses the inadequacy of the reduced-order system model commonly employed in time-domain methods to accurately capture the stability of the original full-order system. By harnessing dissipativity theory, we introduce a model reduction technique coupled with a condition guaranteeing ϵ -exponential stability solely through the employment of the reduced closed-loop system model. This not only validates the use of model reduction strategies but also furnishes a theoretical underpinning for their application. The second challenge pertains to the computational complexity of nonlinear semidefinite programming problems encountered during the coordinated design of controllers. Rather than pursuing the global optimum, we advocate for a path-following methodology to systematically explore local solutions. This iterative algorithm enhances system damping and H 2 performance by orchestrating automatic and coordinated adjustments to control parameters. Numerical experiments conducted on various benchmark systems underscore the efficacy of the proposed approach. • Time delays and model reduction errors are systematically considered in damping controller design. • The controller design problem is formulated as an nonlinear semi-definite program. • A path-following method is developed to effectively solve the problem to local optimality.