基于阵列型压电能量收集器的中高频自供电系统

Medium and High Frequency Self-Powered System Based on Array-Type Piezoelectric Energy Harvester

随着物联网(IoT)的发展,无线自供电传感是实现感知机体状态和飞行环境的重要技术手段。机体振动具有分布范围广,激励频率高和频域宽等特点,单一压电能量收集器难以有效俘获能量。针对上述问题,研制了一套基于阵列型压电能量收集器的自供电传感系统。该系统由阵列型压电能量收集器、电源管理电路、传感节点、低功耗蓝牙及微控制器组成。压电能量收集器采用压电厚膜方案,在谐振频率693 Hz,2 g下最高平均输出功率密度为4 mW·cm^(-3)·g^(-2)。电源管理电路采用改进的整流器设计和欠压锁定电路(UVLO)实现高效能量传输与能量释放,充电速度是普通整流器的1.3倍,最大输出功率达到1.32 mW,结合微处理器进行时序控制可达到动态平衡,实现了固定间隔时间持续的数据读取和发送。

With the development of the Internet of Things(IoT),wireless self-powered sensing has become an important technical means for monitoring the airframe state and flight environment.However,airframe vibrations are characterized by a wide distribution range,high excitation frequencies,and a broad frequency domain,making it challenging for a single piezoelectric energy collector to capture energy effectively.To address these issues,this paper develops a self-powered sensing system based on an array-type piezoelectric energy collector.The system comprises an array-type piezoelectric energy harvester,a power management circuit,a sensing node,a low-power Bluetooth module,and a microcontroller.The piezoelectric energy harvester utilizes a piezoelectric thick-film scheme,achieving the highest average output power density of 4 mW·cm^(-3)·g^(-2)at 693 Hz(resonant frequency)under 2 g acceleration.The power management circuit features an improved rectifier design and an undervoltage lockout(UVLO)circuit,enabling efficient energy transfer and release.The charging speed is 1.3 times faster than that of an ordinary rectifier,and the maximum output power reaches 1.32 mW.Combined with a microcontroller for timing control,the system achieves dynamic balance,allowing for the transmission of data readings at fixed intervals over an extended period of time.