This application discloses a photovoltaic power generation system control method, a photovoltaic power generation system, and a switching apparatus, to reduce a loss of the photovoltaic power generation system. The switching apparatus includes: a switching unit, a detection unit, and a controller. The switching unit includes a first output end, a second output end, a first input end connected to each first DC/DC converter in a one-to-one correspondence, and a second input end connected to each second DC/DC converter in a one-to-one correspondence. The first output end is connected to an input end of a first DC/AC converter, and the second output end is connected to an input end of a second DC/AC converter. The detection unit is separately connected to the first DC/AC converter, the second DC/AC converter, a plurality of first DC/DC converters, and a plurality of second DC/DC converters.