A Transient Frequency Support Control for PV-VSC without Energy Storage Batteries Concerning Irradiation Fluctuation

The PV inverters without energy storage batteries, usually use active power reserve methods to provide active power response when the grid frequency fluctuates. This paper proposes a transient frequency support control based on the precise active power reserve method. Compared with the traditional methods of active power reserve, the proposed method evaluates and designs capacity of active power reserve more accurately under irradiation fluctuations, which helps achieve power support for grid frequency fluctuations. This paper first introduces the basic architecture and principles of the proposed control. Subsequently, the influence of irradiation fluctuation on the capacity of active power reserve of PV inverter is analyzed and revealed by mathematical modeling. A precise designing method for capacity of active power reserve is proposed. Finally, hardware-in-the-loop experiments are used to verify the effectiveness of the proposed method.