Disclosed herein is a photovoltaic inverter (100) that prevents degradation in the efficiency of photovoltaic generation by applying a reverse voltage of a DC voltage stored in a DC link capacitor toa solar cell array. The photovoltaic inverter includes: a DC link capacitor configured to store a DC voltage output from the solar cell array; a power conversion stage configured to generate an AC power by using the DC voltage stored in the DC link capacitor to transmit the generated AC power to a power system; and a controller configured to apply the DC voltage stored in the DC link capacitor tothe power conversion stage or apply a reverse voltage of the DC voltage stored in the DC link capacitor to the solar cell array depending on whether a driving value of the solar cell array satisfies apredetermined driving condition.