Impact of mechanical and electrical hydro governing systems on the LFC of hydro thermal power system under TIDDF controller

Abstract

This paper aims to demonstrate the effect of employing the mechanical and electrical governing systems of the hydro unit on the load frequency control (LFC) of an interconnected hydrothermal power system (IHTPS). The IHTPS has the thermal unit in area 1 and the hydro unit in area 2, and the performance is analyzed for injecting 10% step load disturbance (SLD) in both areas. The investigation is performed under the tilt-integral-double derivative filter (TIDDF) controller optimized with the crow search optimization algorithm (CSOA). However, the competency of the proposed control strategy is evinced by testing on the widely accepted model of a two-area thermal system (TATS), and it is revealed that the suggested control technique outperforms the other control strategies reported in the literature. Later, the analysis on IHTPS is performed by considering the hydro unit with the mechanical governing system, which is later extended to the consideration of the electrical governing system under the same disturbance loadings. Simulation results reveal the significance of employing an electrical governing system with the hydro unit for better frequency regulation of IHTPS over the mechanical one as it has the limited response rate. Furthermore, the investigations on IHTPS extend to the incorporation of the HVDC line to obtain an improvement in dynamic performance.