Maximum power point tracking method and device
AssigneeNational Inst. of Advanced Ind. Science and Tech.
InventorsYuji Kasai, Fumihisa Kano
Life of this patent
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Abstract
The output current value of a direct-current power source obtained by low-frequency, minute modulation of the input voltage of a switching converter is detected in a circuit having an amplification factor switching function that switches the amplification factor between definite magnitudes synchronizing with the modulation, and by using a signal obtained by demodulating in a discriminator circuit the output of this circuit synchronizing with the modulation to control the switching converter, the power point of the switching converter can be tracked to the maximum power point by following the change in state of the direct current power source.
Claims8
A maximum power point tracking method that supplies power of a direct-current power source, having a bow-shaped current-voltage characteristic, to a load via a switching converter, wherein:
- an output current value of said direct-current power source, which undergoes low-frequency, minute modulation of input voltage to the switching converter, is detected in a circuit with an amplification factor switching function that switches the amplification factor between definite magnitudes synchronizing with said modulation, and said switching converter is controlled using a signal obtained in a discriminator circuit by demodulating output of this circuit synchronizing with said modulation.
A maximum power point tracking device that supplies power of a direct-current power source, which has a bow-shaped current-voltage characteristic, to a load via a switching converter, said maximum power point tracking device comprising:
- (1) a circuit for performing low-frequency, minute modulation that alternately switches input voltage of the switching converter between two voltage values;
- (2) a circuit that detects an output current value of said direct-current power source and has an amplification factor switching function that switches the amplification factor between definite magnitudes synchronizing with the modulation in (1) above;
- (3) a discriminator circuit for obtaining a component synchronized with the modulation in (1) of output of the circuit in (2);
- and
- (4) a circuit that uses output of the circuit in (3) to generate a signal that is also input to a switching converter control circuit.
Dependencies are inferred from the claim text.