Maximum-power-point tracking method of photovoltaic power system using single transducer

This paper proposes a maximum-power-point tracking (MPPT) method of a photovoltaic power system with less transducer count. A unique feature of this method is capability to seek the maximum power point, using only a single transducer implemented in a switched dc-dc power converter, i.e., a current transducer or a voltage transducer. Output power of the converter can be estimated with an average value and ripple amplitude of the reactor current or the capacitor voltage detected in the converter. The output power obtained from only the current or the voltage information allows seeking the maximum power point on the basis of a common hill-climbing method. In this paper, not only a theoretical aspect of the proposed method is described, but also several experimental results are presented to prove feasibility of the method.