PHOTOVOLTAIC POWER GENERATION SYSTEM AND POWER FEEDING SYSTEM

According to one embodiment, a photovoltaic system and a power supply system include modules (6, 7) configured to detect a node voltage and an output current of a converter (3), an detector (8) configured to obtain an effective power value from the node voltage and the output current, a system condition detector configured to detect a power supply condition in the electric system (5) or the operating conditions of devices included in the electric system (5) and then output a first signal based on a detection result, a setting unit (11) configured to switch the effective power set value to a preset first value or second value on the basis of the first signal and then output the effective power set value, a rotor speed computation unit (12) configured to calculate an angular frequency of an output voltage of the converter (3) on the basis of an output of the detector (8), the effective power set value, and an output of the system condition detector, and a computation unit (15) configured to calculate an output voltage target value of the converter (3) on the basis of the angular frequency, the output current value, and a set voltage value.