Closed-loop identification and tuning for damping of interarea modes

An iterative closed-loop identification method is applied to obtain linear models of a power system for use in controller design. Two different probing levels are used for model identification to demonstrate both the underlying nonlinear nature of the power system and the effectiveness of using the closed-loop iterative identification method in the case of large probing inputs. The identified plant models contain non-minimum phase zeros, and controllers are designed using linear quadratic Gaussian theory with partial loop transfer recovery (LQG/LTR). Simulation results are presented to illustrate the robustness of the resulting controller to changes in operating point