Research on coordinated control strategy of photovoltaic energy storage system Due to the constraints of climatic conditions such as sunlight, photovoltaic power generation systems have problems such as abandoning light and difficulty in grid connection in the process of grid-connected power generation.
The energy storage unit controls the DC side voltage, and the photovoltaic inverter implements the VSG algorithm. The photovoltaic module, energy storage unit, and photovoltaic inverter have independent functions, and the control is relatively simple.
The simulation results verified that the control method proposed in this paper can reduce the requirements of system coordinated control and smooth the output power of the photovoltaic inverter, which has certain engineering application value.
In this paper, a selective input/output strategy is proposed for improving the life of photovoltaic energy storage (PV-storage) virtual synchronous generator (VSG) caused by random load interference, which can sharply reduce costs of storage device. The strategy consists of two operating modes and a power coordination control method for the VSGs.
In this way, when the light intensity changes greatly and is unstable, due to the existence of the energy storage system, the photovoltaic + storage photovoltaic grid-connected system can operate normally and stably to achieve the purpose of improving the consumption of new energy. Fig. 14.
A control strategy based on a virtual synchronous generator for a PV-storage grid- connected system is proposed, wherein the energy storage unit performs the MPPT algorithm, and the PV inverter performs the VSG control.