Robust automatic generation control regulators for a two-area power system interconnected via AC/DC tie-lines considering new structures of matrix Q

This study discusses the design of robust automatic generation control (AGC) regulators based on the Ricatti-equation approach for a two-area system interconnected via a DC tie-line in parallel with an AC tie-line as an area interconnection between the control areas. The proposed robust AGC regulator designs require only the bounds of the system parameters and enable to ensure the overall asymptotic system stability for all admissible uncertainties. In this study, different models of state cost-weighting matrix (Q) are also developed. Various aspects of controllability and observability of the system states which directly or indirectly affect the system dynamics are identified and used in the design of robust AGC regulators. The results obtained with proposed regulator designs in the wake of 1% load disturbance in area-1 and these results are compared with those obtained with optimal AGC regulators to ensure the superiority of the designed AGC regulators. The system eigenvalues are also presented to check the system stability margins available with the implementation of AGC regulators.