Maximum output power point tracking for photovoltaic energy harvesting systems: Mathematical model and circuit implementation

Maximizing the power transferred to the load is a key feature in any energy harvesting system. Contrary to traditional approaches, this paper mathematically demonstrates that performing a maximum power point tracking on the power delivered to the load instead of on the photogenerated power allows to harvest up to 25% more power due to setting less demanding operating conditions. A circuit implementation of a system that successfully maximizes its output by exclusively taking measurements of the output voltage is designed and demonstrated using a 180 nm commercial CMOS process. The system operates at uW range and achieves a peak power conversion efficiency of 79.04% at 30.74 uW output.

keywords: Energy Harvesting, MPPT, DC-DC converter