During the daytime, under the illumination condition, the solar cell module generates a certain electromotive force, and the solar cell array is formed by series-parallel connection of the components, so that the square matrix voltage reaches the requirement of the system input voltage. The battery is then charged by the charge and discharge controller to store the electrical energy converted from the light energy. In the evening, the battery pack provides input power to the inverter. Through the action of the inverter, the DC power is converted into AC power, which is sent to the power distribution cabinet, and is powered by the switching function of the power distribution cabinet. The discharge condition of the battery pack is controlled by the controller to ensure the normal use of the battery. The photovoltaic power station system should also have limited load protection and lightning protection devices to protect the system equipment from overload operation and lightning strikes, and to maintain the safe use of system equipment. Solar energy → electrical energy → chemical energy → electrical energy → light energy.