A multifunctional electromagnetic generator for omnidirectional wind energy harvesting and self-powered wind vector detection

Constant and accurate wind vector information is an essential component of meteorological monitoring. However, in view of the wide distribution and poor sustainability of Internet of Things (IoT) nodes powered by batteries, traditional sensor technology has limited the development of distributed wind vector monitoring. Herein, we propose a multifunctional electromagnetic generator for omnidirectional wind energy harvesting and self-powered wind vector detection. A Savonius turbine structure is constructed to convert the wind blowing into the rotation of a magnet-embedded rotor, which then induces a voltage in wound coils fixed on a stator. On this basis, average power of 2.16-237.57 mW is obtained with a matched load under the wind speed of 1.80-4.50 m/s, where a superior minimum cut-in wind speed as low as 1.80 m/s is achieved. It is also revealed that the wind speed can be indicated by the root-mean-square value of the induced voltage, with the electromagnetic generator serving as a self-powered wind speed sensor without any external power supply. Besides, results show that an integrated photoelectric wind direction monitoring module has reached a resolution of 10°. This work offers a convenient and self-sustained device for both wind energy harvesting and wind vector detection, which show promising prospects in IoT-based constant meteorological monitoring.