Light storage system state switching control device, photovoltaic system and control method

The invention provides a light storage system state switching control device, a photovoltaic system and a control method. The optical storage system state switching control device comprises a photovoltaic contact, a power grid contact and a load contact. The control device further comprises a first switch module, a second switch module, a third switch module and a control module. The three switch modules are all controlled by the control module; the first end of the first switch module is connected with the photovoltaic contact and the first end of the second switch module, and the second end of the first switch module is connected with the power grid contact and the first end of the third switch module; and the second end of the second switch module is connected with the load contact and the second end of the third switch module. And the control module is used for controlling the second switch module to continue to keep the closed state when the optical storage system is switched from the grid-connected stat