Power conversion device for solar cell

A power conversion device for converting DC electrical power produced by a solar cell as a result of incident light received to AC electrical power and providing the AC electrical power to a commercial AC power source with the AC electrical power having a frequency which is automatically maintained in a predetermined relationship with a frequency of the commercial AC power source, wherein a DC output voltage of the solar cell increases with increases in amounts of incident light reaching the solar cell;

• the power conversion device comprised of:
• a voltage controlled oscillator powered by the solar cell for producing a VCO output with a VCO frequency which varies as a function of a DC output voltage of the solar cell;
• an inverter connected to the solar cell in parallel with the VCO and responsive to the VCO output for converting a DC output current from the solar cell into the AC electrical power having a frequency which varies with VCO frequency so that the frequency of the AC electrical power increases with an increase in the DC output voltage;
• and
• an inductor for coupling therethrough the AC electrical power from the inverter to the commercial power source with a phase difference which varies as a function of the frequency of the AC electrical power, and wherein an amount of the AC electrical power coupled through the inductor increases with increases in the phase difference;
• wherein the DC output current flowing from the solar cell increases with increases in the AC electrical power coupled through the inductor;
• and wherein the DC output voltage of the solar cell tends to decrease with increases in the DC output current flow so that the frequency of the AC electrical power is automatically maintained at an essentially fixed level and is synchronized with the frequency of the commercial AC power source despite variations in the incident light received by the solar cell.