Modelling and control of virtual energy storage based on the inverter air conditioner

With the rapid development of renewable energy represented by distributed photovoltaics (PV),massive flexible regulation resources are urgently needed to reduce the adverse effects of its volatility and uncertainty on the secure and stable operation of power systems. Due to the advantages of high energy density and flexible configuration,lithium batteries have been used in PV consumption. However,because of the expensive cost and unsafety of lithium batteries,it is difficult to implement them widely within a few years. A virtual energy storage(VES)modeling method and control strategy for distributed PV consumption are proposed by utilizing the inverter air conditioner with flexible power regulation ability. Firstly,based on the established equivalent thermal parameter model of the room and the operating model of the inverter air conditioner,a modeling method of the VES charging and discharging processes is proposed. Subsequently,in order to realize the statues perception and regulation capacity evaluation of the VES,several evaluation indexes of VES are proposed. On this basis,aiming at distributed PV consumption,a VES control strategy considering charge and discharge rate constraints is proposed. Finally,using the actual PV output data,the process of VES participating in PV fluctuation stabilization is simulated,and the effect of VES with different capacities is compared. The results show that the VES constructed by the inverter air conditioner can effectively damping the photovoltaic fluctuation and promote the grid friendly integration of renewable energies.