Photovoltaic device

A photovoltaic device compromising:

• a light concentration unit for concentrating incident solar energy;
• a solar cell module converting the solar energy concentrated in the light concentration unit into electrical energy and outputting direct current (DC) power;
• a light amount detection unit for detecting a light amount of the solar energy;
• a battery module charged by receiving the DC power from the solar cell module;
• a power detection unit for detecting the DC from the solar cell module;
• a first comparator comparing the DC power from the solar cell module detected by the power detection unit with a charged voltage of the battery module, and outputting a first comparison result signal;
• a second comparator comparing a light amount of the solar energy detected by the light amount detection unit with reference light amount data indicating a light amount enough to be converted into the electrical energy, and outputting a second comparison result signal;
• a third comparator comparing the charged voltage of the battery module with over-discharge reference voltage data, and outputting a third comparison result signal;
• a fourth comparator comparing a charged voltage of the battery module with over-charge reference voltage data and outputting a fourth comparison result signal;
• an auxiliary power generation unit, which operates when a light amount of the solar energy is less than the reference light amount data, rotates an AC motor or a DC motor by means of the DC power, decelerates or accelerates the number of revolutions of motive power, and generates and outputs auxiliary electrical energy;
• a distribution controller for controlling the supply and cut-off of the DC power from the solar cell module to the battery module according to the first, second, third and fourth comparison result signals;
• and
• an AC output driver converting charged power of the battery or the DC power from the solar cell module into alternating current (AC) power having a frequency of 400 Hz to 1200 Hz and outputting the AC power to a load.