Device for controlling photovoltaic cell to generate power along with environment illumination change in a stage way and power generating system

The invention discloses a device for controlling a photovoltaic cell to generate power along with environment illumination change in a stage way, which is used in a photovoltaic power generating system. The photovoltaic power generating system comprises a solar-cell panel and a storage battery set including a plurality of sub-storage battery sets. The control device comprises: the plurality of sub-storage battery sets are connected in series; the positive electrode of the last stage of sub-storage battery set is connected with the positive electrode of the solar-cell panel; the positive electrode of each stage of sub-storage battery set is connected with the negative electrode of the solar-cell panel through a control branch; and the control device is used for turning on or turning off corresponding control branches according to the detected current total storage voltage of the storage battery set and the current voltage of the solar-cell panel, so that the corresponding sub-storage battery sets enter or quit a charging state. The invention further provides a solar photovoltaic power generating system. By using the embodiment of the invention, the changeable power generation properties of the solar photovoltaic power generating system under the illumination conditions in different periods in all day can be utilized sufficiently; the photovoltaic power generating efficiency is improved; and the energy is prevented from being wasted.