A NOVEL FREQUENCY REGULATION STRATEGY FOR SINGLE-STAGE GRID-CONNECTED PV GENERATION

With the rapid development of PV generation, the synchronous generator space with rotational inertia has been crowded out. At the same time the reserve capacity of primary frequency regulation is decreased and the disturbance rejection ability is weakened. There is an urgent need to study PV generation actively taking part in power grid frequency regulation. This paper uses the single-stage PV generation as the research target, and proposes a novel system frequency support strategy based on the active power reserve, which introduces a f-U-dc compensation link to the DC-link voltage control loop of voltage source converter (VSC). The linear relationship between the DC-link voltage of PV array and frequency deviation is established in this paper. When the system frequency changes, the DC-link voltage reference U-dcref will be corrected by the f-U-dc compensation link and then the VSC will control the PV generation increase or decrease the power to counterbalance the grid frequency variation. The effectiveness of the control strategy is verified by the simulation results in time domain.