Dynamic performance enhancement of interconnected hybrid thermal power system in the presence of electric vehicles

The prolific integration of non-synchronous distributed energy resources and energy storage systems (EES) into thermal-dominated grids significantly impact the power system's total synchronous inertia (TSI). The TSI, in turn, affects the frequency response of the electrical grid (EG). Although the EES supports frequency regulation, the cost is a vital factor in determining their role. Lately, it is realized that incorporating plug-in hybrid electric vehicles (PHEVs) as auxiliary power sources can provide inertial support if penetrated in huge numbers into the EG. This work proposes a supply and demand variation approach that integrates EVs in load frequency control (LFC). The proposed LFC uses the biogeography-based optimization (BBO) algorithm. A parallel direct current (DC)-alternating current (AC) interconnected hybrid thermal power system (IHTPS) with different types of high voltage direct current (HVDC) tie-links in the presence of PHEVs is simulated. The settling time, oscillations, and first peaks are mainly analyzed for the considered HVDC tie-links. The results show that the virtual synchronous power-HVDC tie-link offers better dynamic performance than that of the other tie-link, proving EV's presence in improving the frequency response. Thus, the investigation demonstrates the BBO based LFC role in enhancing the dynamic performance of the IHTPS.

Automated summary

The integration of non-synchronous distributed energy resources and energy storage systems into thermal grids affects the total synchronous inertia, which in turn impacts the frequency response of the electrical grid. The study proposes incorporating plug-in hybrid electric vehicles into load frequency control using a biogeography-based optimization algorithm. Results show that a virtual synchronous power-HVDC tie-link outperforms other tie-links in improving the frequency response, highlighting the role of EVs in enhancing dynamic performance.