自供电传感器的多源复合微能源能量管理研究

The power source of sensors has become one main bottleneck which restrict further development of Internet of Things. Energy harvesting has been proved a pressing need for self-powered sensors. However, a single energy harvester cannot usually meet the power requirements of sensors. Aiming at the environmental multiple energy sources: mechanical vibration energy, light energy and thermal energy, the proposed project will carry out the fusion and distribution of the multiple input energy sources based on piezoelectric-photoelectric-thermoelectric mechanism, construct a new hybrid model for energy harvester, power management circuit and storage energy device, and reveal the fusion mechanism. So the scientific problems for energy transmission, management, storage and release will be solved. And a power management circuit chip for self-powered sensors is designed based on the breakthrough of key technologies of ultra-low power consumption for self-powered circuit. The novel Energy Neutral Algorithm to balance the input energy and the load demand will be also put forward innovatively under complex environmental conditions to improve the overall efficiency of the whole energy system. Another novel method of low input voltage start-up using MEMS passive switch will be made based on nonlinear switching technology to make a breakthroughs in electrical limit of DC-DC converter. The research achievements will lay a strong foundation and provide technical support on implementing self-powered sensors. It has important scientific research significance and practical application value.

传感器的电源问题已成为制约物联网发展的主要瓶颈，迫切需要传感器实现基于环境能量收集的自主供电。然而单一的环境能量收集方式往往不能完全满足传感器的供电需求，课题针对传感器应用环境中最常见能量源：机械能、光能和热能，提出基于压电-光电-热电能量转换机制，开展多源能量收集的复合与分配研究，建立多源能量收集器-电源管理电路-储能器件三者为一体的微能源整体系统模型，揭示多源能量的复合机理，解决微能量传输与耗散、储存与释放等基础科学问题，突破低功耗自供能电路设计关键技术，设计多源能量收集的复合微能源电源管理芯片。课题创新性地提出采用多变环境条件下输入能量与负载需求的能量分配新算法来提高微能源系统整体效率；提出基于MEMS无源开关的超低输入电压启动新方法来突破DC-DC低电压启动的电学极限问题。课题研究成果将为传感器实现自主供电奠定坚实的理论基础和提供技术支持，具有重要科学研究意义和实际应用价值。

目前传感器主要采用传统的电池供电方式，一旦电池能量耗尽，传感器便失去功能，所以电池有限的使用寿命已经成为制约传感器发展的瓶颈。基于环境能收集的自供电传感器是将传感器工作环境中的能量如机械能、光能、温差等转换为电能为传感器供电，理论上可为传感器提供永久的长寿命、免维护的工作电源。课题针对基于环境能量收集的微能源与自供电传感，开展了多源能量收集（机械能、光能和热能）的能量管理与分配基础理论及技术研究，建立了微能源系统模型，揭示了多源能量的复合机理，设计了多源能量收集的微能源管理芯片；针对TENG自供电传感的高阻抗、高电压、小电流、弱电荷信号难以测试表征的问题，提出了一种具有高精度高可靠性的测量方法；针对环境间歇式微能量收集和存储的难题，提出了优化的次级能量转移策略，基于低功耗开关的电量判定和定时方式，建立了自适应的微能源释放方法，有效提高了能量收集效率；针对自供电传感器难以同时兼顾能量收集和感知信号的难题，采用并行和分时的方法实现了基于TENG器件真正意义的自供电传感系统。课题研究的多源能量收集的微能源管理芯片、基于TENG自供电传感等成果为环境能量收集、自驱动传感奠定了坚实的理论基础和技术支撑，具有重要科学研究意义和实际应用价值。