新型微型电磁式振动能量收集器

New micro electromagnetic vibration energy harvester

提出一种新型电磁振动能量收集器,该能量收集器主要包括静线圈和由磁体、质量块与平面弹簧构成的拾振系统。理论分析得到拾振系统在谐振频率工作时,相对位移最大,有利于收集振动能量。为了得到结构合理、性能优良的能量收集器,对能量收集器拾振系统进行限元建模分析,得到弹簧片厚度、弹簧臂宽度、弹簧臂长度与振动特性的关系;对能量收集器能量转化系统进行有限元建模分析,得到线圈匝数,永磁铁的长、宽、高,线圈磁铁间距,磁铁振幅以及振动与频率输出电压的关系。对确定尺寸的模型,工作在谐振频率45.4 Hz时,仿真分析得到最大输出电压为205 mV。

A new kind of micro electromagnetic vibration energy harvester of flat spring was proposed.The energy harvester includes static coil and vibration picking system with magnets,mass and spring.Theoretical analysis results show that vibration energy can be collected easily when work frequency is resonance frequency and relative displacement is the largest.In order to get the optimum energy harvester,finite element method was used to build collection system model.The relationship among vibration characteristic and thickness of spring,width of elastic beam and length of elastic beam is gotten through finite element analysis.The finite element analysis was used to build energy conversion system.The relationships among peak output voltage and turns of coil,length,width and height of magnet,distance,amplitude and frequency are obtained.When the size of model is determined and resonant frequency is 45.4Hz,the maximum output voltage is 205 mV.