一种采用频率变换的自供电电源管理电路

 在低频率条件下,采用直接阻抗匹配的原理,设计的压电材料换能器电源管理电路,匹配电感值很大.本文采用频率变换,设计了一种自供电电源管理电路.分析了频率变换的原理.将低频信号变换至较高频率,匹配电感值很小,有利于电路的小型化.该管理电路还可以在宽频带内对于压电换能器实现匹配.实验结果表明,电路实现了频率变换,匹配电感值和电路体积都大大减小.电源管理电路的最大采集功率为181.6mW,能量采集效率可以达到44.8%.当0.47法拉的储能电容电压为1.13V时,该电路最大放电功率可达110mW,放电时间持续620ms,能够驱动无线传感器在一个周期内正常工作.

A Self-Powered Power Supply Management Circuit Using Frequency Conversion Network

In low frequency applications,a large inductance is needed for directly matching the piezoelectric transducer impedance in the power supply management circuit.This paper designs a self-powered piezoelectric energy harvesting circuit using frequency conversion.The principle of frequency conversion is analyzed.Because the low frequency can be converted to a higher frequency by using a small matching inductance,the size of the power supply management circuit is very small.The circuit can realize the matching for the piezoelectric transducer in a wide range of frequency bandwidth.The experiment results show that the frequency of the transducer can be converted,and the matching inductance and the management circuit size can be decreased.The maximum harvesting power of the management circuit is 0.182mW,and the energy harvesting efficiency can reach 44.8%.When the voltage of the supercapacitor reaches 1.13V,the circuit can drive a wireless sensor node with a power consumption of 110mW at 620ms.