Dynamic frequency support by photovoltaic generation with “synthetic” inertia and frequency droop control

Recently solar photovoltaic (PV) power generation increases rapidly all over the world. Because of variability, uncertainty, stability and reliability of power system with high penetration of PV generation faces challenges. Frequency stability is one most important thing for power system. In this paper, “synthetic” inertia control and frequency droop control for PV power generation is proposed, with de-loaded operation. “synthetic” inertia control is used to prevent frequency change rate once disturbance occurs, and differential of frequency signal is leaded into control structure of PV inverter. Frequency droop control is used to re-establish frequency after disturbance, using deviation between frequency and its reference. PV power generation, with control method demonstrated as above, is performed in software DIgSILENT PowerFactory, to evaluate the dynamic frequency support capability of PV power generation to power system. The simulation results are demonstrated that PV generation is capable to support dynamic frequency.