Dynamic Frequency Support by Photovoltaic System with Virtual Inertia Control in Microgrid

In recent years, the usage of PV system is increasing in the power system. Typically, PV power generation is uncontrollable and depends on solar irradiance and temperature. In addition, PV has no moment of inertia due to the lack of rotational part. Hence, the PV penetration affects the frequency stability of system because of the reduction of the system inertia. This paper proposes the integration of virtual inertia to the PV system without using battery energy storage. The proposed approach is used for enhancing frequency stability by using power reserve from PV itself. This paper employs an adaptive neuro-fuzzy inference system (ANFIS) for adjusting the virtual inertia value to be suitable for the system. Moreover, ANFIS is used to adjust the power reserve of PV according to the strength of the system. To evaluate the results from the proposed virtual inertia method, a microgrid test system is simulated in MATLAB/Simulink for observing the performance of the proposed control method. The results show that the proposed control method is superior to the constant inertia. Although PV virtual inertia is helpful to the system, power generation will be decreased for reservation in case of an unexpected situation.