| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a power supply with a constant output voltage at low cost, by following up a maximum output power point in operation using a simple constitution, regardless of intensity of sun light or temperatures. SOLUTION: Solar energy is converted into electric energy by a solar battery 15 to generate a DC voltage. The DC voltage of the solar battery 15 is changed into a given DC voltage and fed from a chopper circuit 100. The DC voltage from the chopper circuit 100 is charged in a battery 200. A pulse width modulation controller 300 detects a maximum point of output power, through the output voltage and output current from the solar battery 15. A pulse width modulation control is carried out in order to follow up the output current of the solar battery 15 on the basis of the detected power signal, so as to operate the chopper circuit 100 at maximum output power.</p> |
