Power conditioning units

Abstract

We describe a power conditioning unit with maximum power point tracking (MPPT) for a dc power source, in particular a photovoltaic panel. A power injection control block has a sense input coupled to an energy storage capacitor on a dc link and controls a dc-to-ac converter to control the injected mains power. The power injection control block tracks the maximum power point by measuring a signal on the dc link which depends on the power drawn from the dc power source, and thus there is no need to measure the dc voltage and current from the dc source. In embodiments the signal is a ripple voltage level and the power injection control block controls an amplitude of an ac current output such that an amount of power transferred to the grid mains is dependent on an amplitude of a sinusoidal voltage component on the energy storage capacitor.

Dependencies are inferred from the claim text.