Resilient Optimal Gain Control and Continuous Twisting Observer for Enhanced Power System Performance Under Uncertainties

In this article, resilient optimal gain control is presented for a multimachine power system for mismatched uncertainty compensation and to damp out the interarea oscillations. The proposed control scheme is analyzed in two substeps. In the first step, a power rate reaching law-based virtual control is designed, whereas the main control input in the second step is formulated using optimally tuned gains. Thus, this method does not incorporate multiple differentiation, unlike existing backstepping methods, hence eliminating magnitude limiter, rate limiter, and command filter dependence. The controller is designed by separating power system nonlinearities to eliminate complex expression from the control input that reduces the control computation. The proposed method has two steps procedure in control designing that suppresses the recursive step error in multistep virtual control formulation of backstepping methods. Furthermore, a nonlinear observer is designed using continuous twisting law with the integral surface design to counter the mismatched uncertainties along with the disturbance rejection. The proposed scheme is validated in MATLAB/Simulink and in real-time digital simulator platform of IEEE Standard New England 39-bus, 10-machine power system and compared with the existing methods.