Disturbance Rejection Based Controller for Frequency Control of Restructured Power System

Abstract

In regard to the present-day electrical power scenario, this article reports a power generation control of restructured hybrid power system with a multi-source combination of solar-thermal, geothermal, electric vehicle (EV), and conventional thermal system. Involvements of renewables and EVs in an electrical grid system with appropriate system non-linearities make the power system complex and a practical one. Such a system needs a robust controller to function optimally. In view of this, several controllers are examined for system dynamics. Performance comparison reveals the novel disturbance rejection-based fractional-order–proportional–integral–derivative (DR-foPID) as an optimal controller. Furthermore, the impact of energy storage devices (ESD) such as redox flow battery (RFB) for system dynamics enhancement are explored. To obtain the optimal performance of the linked restructured power system, the secondary controller gains and other parameters are optimized using a powerful biogeography-based krill herd (BBKH) optimization technique. The results indicate that with the proposed controller, a 38% reduction in response undershoot, a 13% reduction in overshoot, and a 8.3% reduction in settling time are exhibited. Moreover, the objective function (error) values for the proposed controller reduce to 95% with respect to other controllers. The effect of renewables and EVs on system stability is also studied. Moreover, the proposed secondary DR-foPID controller is also examined on a three-area hybrid regulated power system. Sensibility evaluation related to different alterations in nominal system parameters verifies the strength of the DR-foPID controller.