Patent ID: 6844739
Filing Date: 2005-01-18
Classification: G05F,H02J,H02M,Y02E

Abstract:
1. A maximum power point tracking method for use in a system in which power from a direct-current power source, which has a bow-shaped current-voltage characteristic, is supplied to a load via a switching converter, the method comprising: performing low frequency, minute modulation of an output voltage of the direct-current power source; detecting an output current value of the direct-current power source in a current detection circuit after performing the modulation, the current detection circuit being configured to perform an amplification factor switching function that switches an amplification factor of the current detection circuit between definite magnitudes in synchronization with the performed modulation to produce an output; and controlling said switching converter using a signal obtained in a discriminator circuit by demodulating the output of the current detection circuit in synchronization with the performed modulation.