Bruzzi Mara, Pampaloni Giovanni, Cappelli Irene, Fort Ada, Laschi Maurizio, Vignoli Valerio, Vangi Dario
Department of Physics and Astronomy, University of Florence, Via G. Sansone 1, 50019 Florence, Italy.
National Institute of Nuclear Physics INFN, Florence Section, Via G. Sansone 1, 50019 Florence, Italy.
Sensors (Basel). 2024 Sep 30;24(19):6340. doi: 10.3390/s24196340.
A novel prototype based on the combination of a multi-junction, high-efficiency photovoltaic (PV) module and a supercapacitor (SC) able to self-power a wireless sensor node (WSN) for outdoor air quality monitoring has been developed and tested. A PV module with about an 8 cm active area made of eight GaAs-based triple-junction solar cells with a nominal 29% efficiency was assembled and characterized under terrestrial clear-sky conditions. Energy is stored in a 4000 F/4.2 V supercapacitor with high energy capacity and a virtually infinite lifetime (10 cycles). The node power consumption was tailored to the typical power consumption of miniaturized, low-consumption NDIR CO sensors relying on an LED as the IR source. The charge/discharge cycles of the supercapacitor connected to the triple-junction PV module were measured under illumination with a Sun Simulator device at selected radiation intensities and different node duty cycles. Tests of the miniaturized prototype in different illumination conditions outdoors were carried out. A model was developed from the test outcomes to predict the maximum number of sensor samplings and data transmissions tolerated by the node, thus optimizing the WSN operating conditions to ensure its self-powering for years of outdoor deployment. The results show the self-powering ability of the WSN node over different insolation periods throughout the year, demonstrating its operation for a virtually unlimited lifetime without the need for battery substitution.
一种基于多结高效光伏（PV）模块和超级电容器（SC）组合的新型原型已被开发并测试，该原型能够为用于户外空气质量监测的无线传感器节点（WSN）自供电。组装了一个有源面积约为8平方厘米的光伏模块，它由八个基于砷化镓的三结太阳能电池制成，标称效率为29%，并在地面晴空条件下进行了特性表征。能量存储在一个4000 F/4.2 V的超级电容器中，该超级电容器具有高能量容量和几乎无限的寿命（10个循环）。节点功耗针对以发光二极管作为红外源的小型化、低功耗非分光红外（NDIR）一氧化碳传感器的典型功耗进行了调整。在选定的辐射强度和不同的节点占空比下，使用太阳模拟器设备在光照条件下测量了连接到三结光伏模块的超级电容器的充放电循环。在户外不同光照条件下对小型化原型进行了测试。根据测试结果开发了一个模型，以预测节点能够容忍的最大传感器采样次数和数据传输次数，从而优化WSN的运行条件，以确保其在户外部署多年的情况下能够自供电。结果表明，WSN节点在全年不同日照时段都具有自供电能力，证明其在几乎无限的寿命期内无需更换电池即可运行。
