光伏电池室内光能采集系统的研究进展与展望

Research Progress and Prospects of Photovoltaic Cell Indoor Light Energy Harvesting System

随着5G时代的到来,届时将存在数量庞大的室内物联网设备。尽管大多数室内物联网设备是低功率产品,但它们通常是分布式的,且需要定期更换供电设备,这会导致成本增加和工作不便,而环境能量采集技术正好可以解决这一难题。环境中的光能是最值得被开发利用的能源之一,光伏电池室内光能采集系统正是通过采集周围光能并转换成电能,达到为室内低功耗物联网设备供电的目的。本文针对如何最大化地延长光伏电池室内光能采集系统为室内低功耗物联网设备供电的时间这一主要问题,从高效率采集室内光能、最大功率点跟踪和储能选择三个方面进行简要综述。首先通过对比分析室内光源下带隙值,串并联电阻的大小和电池种类对光伏电池弱光性能的影响,提出了一种高效率采集室内光能的方案;其次从工作原理、优缺点和技术特征等方面分析讨论各类最大功率点追踪技术,指出开路电压比例系数法可能最适合用于室内场景下光伏电池的最大功率点追踪;最后分析和讨论超级电容和可充电电池各自存在的优缺点,指出在光伏电池室内光能采集系统的储能选择方面,可充电电池与超级电容结合使用的储能模块可能是一个有前途的发展方向,为进一步推进室内光能采集系统的设计提供参考。

There will be a huge number of indoor internet of things(IoT)devices with the advent of the 5G era.Although most indoor IoT devices were low-power products,they were usually distributed and required regular replacement of power supply equipment,which inevitably led to increase cost and inconvenience.Environmental energy harvesting technology can solve this problem.The light energy in the environment was one of the most worthy of development and utilization of energy.The photovoltaic cell indoor light energy harvesting system achieved the purpose of powering indoor low-power IoT devices by harvesting ambient light energy and converting it into electrical energy.In this paper,a brief overview of the main issue on how to maximize the time of the photovoltaic cell indoor light energy harvesting system to power indoor low-power IoT devices was provided from three aspects including high-efficiency collection of indoor light energy,maximum power point tracking and energy storage options.Firstly,a scheme of high-efficiency harvesting indoor light energy was proposed by comparing and analyzing the influence of the band gap value,the size of the series and shunt resistance and the types of cell on the weak light performance of the photovoltaic cell.Secondly,the open circuit voltage proportional coefficient method was pointed out that it may be most suitable for the maximum power point tracking of photovoltaic cells in indoor scenarios by analyzing and discussing various maximum power point tracking technologies from the aspects of working principle,advantages and disadvantages and technical characteristics.Finally,the advantages and disadvantages of supercapacitors and rechargeable batteries were analyzed and discussed.It was pointed out that the energy storage module combining rechargeable batteries and supercapacitors may be a promising development in terms of energy storage options for photovoltaic cell indoor light energy harvesting systems.This work may provide a reference direction for further advancing the design of indoor light energy harvesting system.