An ultra-low-power MPPT architecture for photovoltaic energy harvesting systems

In this paper, a maximum power point tracking (MPPT) architecture for micro-scale photovoltaic (PV) energy harvesting systems is presented. A switching DC-DC boost converter is used to provide the required voltage for the circuits of the ultra-low-power application. The MPPT tracks different illumination intensities through changing the input impedance of the boost converter. The proposed technique depends on maximizing the voltage delivered by the boost converter to a test load whose value is constant. Maximizing the voltage of the test load leads to extracting the maximum available source power. The proposed algorithm employs simple and low-power circuits to change the switching frequency of the boost converter to track different illumination conditions. The proposed system has been implemented in a low-cost CMOS 130nm technology. It consumes a quiescent current less than while achieving an average tracking efficiency (TE) of 96% and occupies an area of 0.175mm2.