自供电式同步翻转电荷提取电路的优化设计

Optimized Design of Self-powered Synchronous Inversion and Charge Extraction Circuit

目的解决现有接口电路俘能效率低、开关控制电路模块结构复杂等问题。方法基于电压翻转及电荷提取技术,提出一种自供电式同步翻转电荷提取的压电能量俘获电路(Self-Powered Optimized Synchronous Inversion and Charge Extraction Circuit,SP-OSICE)。该电路设计了2个电压峰值检测电路,检测压电换能器两端电压峰值,并在正峰值处进行一次电压翻转,然后在负峰值处采用同步电荷提取方法,提取压电换能器寄生电容上储存的电荷,提高能量的收集效率。结果在低负载区,SP-OSICE电路的输出功率略低于SICE电路的输出功率,随着负载电压的增大,SP-OSICE电路的输出功率略高于SICE电路,且可达到全桥整流电路最大输出功率的6倍以上。结论SP-OSICE电路优化了SICE电路中的开关控制策略,无需整流桥结构,提高了接口电路的输出功率。整体电路采用自供电设计,无需外部辅助电路控制晶体管通断,降低了电路结构的复杂性。仿真和实验结果均验证了SP-OSICE电路的优势。

Aiming at the problems of low energy capture efficiency of existing interface circuits and complex structure of switch control modules,this paper presents a self-powered optimized synchronous inversion and charge extraction(hereinafter referred to as SP-OSICE)circuit,in which two passive peak detectors are employed to detect the extreme vibration displacement of the piezoelectric transducer.At the positive maximum,the voltage of the piezoelectric transducer is inversed.While at the negative maximum,the accumulated charge on the piezoelectric transducer is extracted,which can improve the energy capture efficiency of the interface circuit.The simulated and experimental results show that the output power of the SP-OSICE circuit is slightly lower than that of the SICE circuit when connected to the load with low impedance value,and higher than that of the SICE circuit as the load impedance increases.Compared to the FBR interface circuit,the output power of the SP-OSICE circuit is improved by six times.The SP-OSICE circuit optimizes the switching control strategy in the SICE circuit,excluding the recti-fier bridge structure,and increases the energy capture ability of the interface circuit.Moreover,the overall circuit adopts a self-powered design and without requiring an external auxiliary circuit to control the transistor on and off,which reduces the complexity of the circuit structure.Both simulation and experimental results verify the advantages of the SP-OSICE circuit.