小型低频电磁式振动能量采集器的制作及其特性研究

Study on Fabrication and Properties for Small Low-Frequency Electromagnetic Energy Harvester

典型的环境振动能量采集器件采用片状的悬臂梁弹簧结构,当这种类型器件的尺度为mm量级时其共振频率较高,这在实际应用中难以与环境中低频振动源进行机械耦合。为此,提出一种回形弹簧结构,并结合电磁感应发电原理,设计和制作了一种低频电磁式振动能量采集器件。在该器件中,使用厚度为100μm的304不锈钢片制作回形弹簧,使得器件的共振频率低至17.8 Hz。整个器件由回形弹簧、Nd Fe B永磁体、自绕线圈和支座组成,外形尺寸为28 mm×28 mm×16 mm。实验测试表明,当激励振动的振幅为500μm时,器件的开路峰值电压为1.82 V,输出功率为1.1 m W。

The structure of typical ambient vibration energy harvesting device uses flake cantilever spring, which is difficult to make mechanical coupling with vibration source in the practical application, with the millimeter-sized device resulting in higher resonant frequency.A flexuous spring structure was presented, and a small low-frequency electromagnetic energy harvester was de- signed and fabricated according to electromagnetic induction law.The resonant frequency of the device was just 17.8 Hz by using 100 μm thickness of 304 stainless steel sheet to make flexuous spring.The device consists of a flexuous spring, a permanent mag- net of NdFeB, a designed coil,an enclosure and the whole size is 28 mm×28 mm×16 mm.Initial measurement shows that the peak open-circuit voltage value is 1.82 V and the output power is 1.1 mW when the vibration energy harvester is under a shock with an amplitude of 500 μm.