Inverter and PV system

It provides an inverter apparatus, and a solar power generation system. In the power conditioner, the DC power from the solar cell more efficiently into AC power. The inverter device comprises: a first switch and a second switch connected in series, and a first switch group connected to the DC power source; a capacitor having one end connected to the first connection point of the first switch and the second switch; a series of the third switch and the fourth switch is connected to the second switch group connected to the capacitor in parallel; by performing on-off control of the first switch, second switch, third switch and fourth switch, from the DC power source DC voltage into an alternating voltage, the switching control unit from the second connection point of the output AC voltage of the third switch and the fourth switch; and a second connection point is connected to the AC voltage pulse waveform is smoothed in the smoothing circuit.