Energy harvesting and speed sensing with a hybrid rotary generator for self-powered wireless monitoring

具备能量采集和速度感知的复合式能量采集器及其自传感应用

Real-time onboard health monitoring systems are critical for the railway industry to maintain high service quality and operational safety.However,the issue with power supplies for monitoring sensors persists,especially for freight trains that lack onboard power.Here,we propose a hybrid piezoelectric-triboelectric rotary generator(HPT-RG)for energy harvesting and vehicle speed sensing.The HPT-RG incorporates a rotational self-adaptive technique that softens the equivalent stiffness,enabling the piezoelectric non-resonant beam to surpass resonance limitations in a low-frequency region.The experiments demonstrate the feasibility of using the HPT-RG as an energy harvesting module to collect the rotational energy of the freight rail transport and power the wireless temperature sensors.To allow multiple monitoring in confined spaces on trains,a triboelectric sensing module is added to the HPT-RG to sense the operation speed and mileage of vehicles.Furthermore,the generator exhibits favorable mechanical durability under more than 600 h of official testing on the train bogie axle.The proposed HPT-RG is essential for creating a truly self-powered,maintenance-free,and zero-carbon onboard wireless monitoring system on freight railways.

实时车载健康监测系统对铁路行业保持高质量服务和运行安全至关重要.然而,目前监测系统中传感器的电源供应问题仍然存在,特别是对于缺乏车载电源的货运列车.为此,本论文提出了一种用于车辆能量收集和速度感知的压电-摩擦电复合式旋转能量采集器(HPT-RG).HPT-RG借助旋转自适应技术软化驱动梁的等效刚度,促使压电梁突破谐振的限制而工作在超低频领域.实验表明,HPT-RG可以将列车的旋转能量转化为电能,进而驱动无线温度传感器工作.为了在列车轴箱有限空间内实现多维监测,HPT-RG增加了摩擦电传感模块来感知车辆的运行速度和里程.此外,样机在列车转向架轴箱轴承上进行了超过600 h的官方测试,测试结果表明样机具有较好的机械耐久性.本文提出的HPT-RG对于建立货运列车自供电、免维护和零碳车载无线监控系统至关重要.