An AC-DC Wind Energy Harvesting Circuit with Extended Input-Voltage Range and 95% Tracking Efficiency

A novel wind energy harvesting (WEH) system using micro-watt turbines is proposed in this paper. To extend the range of wind velocities the harvesting system can process and enhance the settling at the same time, we proposed to use the parasitic inductor of the wind turbines for local excitations. Two-stage power converter is utilized in this system, including a regulator and a maximum power extraction (MPE) implemented in the same chip. The smallest input voltage can be as low as 0.25 V and the settling time is less than 0.2 s with a 1 mF rectified capacitor. This work is fabricated in TSMC 0.35-μm process, achieving 63% end-to-end efficiency. The total active area is 7.68 mm 2 .