The invention discloses a photovoltaic power generation system and a method. The system comprises a photovoltaic power generation system, wherein the photovoltaic power generation system comprises a photovoltaic power generation unit, a convergence unit, a DC switch, a bus capacitor, an inversion power module, a grid-connected reactor, a network-side grid-connected switch, a control unit and a power supply, wherein the DC switch is connected among a battery, the convergence unit and the inversion power module, the network-side grid-connected switch is connected between the grid-connected reactor and a power grid, and an output end of the power supply is connected with the DC switch, the network-side grid-connected switch and the control unit separately.