Optimal AGC of a multi-area power system with parallel AC/DC tie lines using output vector feedback control strategy

This article presents the design of optimal automatic generation control (AGC) regulators using output feedback control strategy for a multi-area interconnected power system. The power system consists of unidentical areas having diverse type turbines. The parallel AC/DC tie-lines are considered as area interconnection between the areas. Efforts have been made to propose optimal AGC regulators based on feedback of output state variables, which are easily accessible and available for measurement. In addition, a modified area control error incorporating DC tie-line power deviation is used in the design of optimal AGC regulators. The designed optimal AGC regulators are implemented and the system dynamic responses for various system states are obtained considering 1% load perturbation in one of the areas. The system dynamic performance is compared with that obtained with optimal AGC regulators designed using full state vector feedback control strategy. The pattern of closed-loop eigenvalues is also determined to test the system stability.