Maiden application of APSO to automatic generation control-a new approach to interconnected hydrothermal system

Accurate modelling of discrete AGC controllers for interconnected power systems

“…However, it does not cause system instability and system works satisfactorily with the slight deterioration in system dynamic performance. The actual configuration of discrete supplementary controllers has been presented. The improper configuration of discrete supplementary controllers has been considered in the papers appeared from the last 15 to 20 years [15–31]. The ZOH circuit has been misplaced with respect to the controllers in the transfer function models of discrete AGC controllers; therefore the controller's action no longer remains in discrete mode.…”

“… Transfer function models of AGC system (a) Model of Type‐1 DCC (actual), (b) Model of Type‐2 DCC (previously used) [15–31], (c) Model of two area AGC system with Type‐1/Type‐2 discrete controller configurations…”

“…Hence, it can be concluded that Type‐1 discrete controller configuration presents the actual dynamic responses of the system because the control signals fed to speed changer set points are in the form of discrete pulses having constant amplitude during the interval of sampling period. However, Type‐2 discrete controller configuration used in the previous AGC studies generates the piecewise linear signals to change the speed changer set points [15–31]. Therefore, the controller action is not discrete and it will not avoid wear and tear of steam turbine and other mechanical components.…”

“…Recently, discrete AGC systems were analysed by many researchers [15–31]. Based on recent literature survey, authors still found serious mistake accrued in the current studies pertaining to discrete AGC systems.…”