Power system stabilization by charging power management of Plug-in Hybrid Electric Vehicles with LFC signal

In the transport sector, Plug-in Hybrid Electric Vehicle (PHEV) is being developed as an environmentally friendly vehicle. The electric energy of PHEVs is charged mainly during nighttime when the electricity price is low. Therefore, we have proposed a charging power control of PHEVs to compensate the Load Frequency Control (LFC) capacity in the nighttime. In this study, we propose a control method based on Area Control Error (ACE) and frequency characteristic of PHEV K_PHEV, which is a change in charging power divided by a change in frequency. ACE is a required adjustment in generation to keep the balance of supply-and-demand; hence, we can also keep the balance by adjusting the demand as much as ACE. LFC signal f_LFC calculated by the following equation f_LFC = -ACE/ K_PHEV is dispersed to all PHEVs; then, PHEVs control the charging power on the basis of f_LFC. We evaluated the proposed control method by using an interconnected 2-area model and obtained the following results. Charging power control based on the proposed method can effectively suppress tie-line flow deviation and frequency deviation, and it could substitute for LFC capacity.