自供电的压电振动能与温差热电能融合采集电路设计

Self-Powered Piezoelectric Energy and Thermoelectric Energy Fusion Harvesting Circuit Design

环境能量俘获中压电振动能和温差热电能的俘获电路设计已成为近几年研究的热点之一。但由于存在压电换能器和热电换能器输出的能量分别是交、直流形式而难以同时俘获,且热电换能器的开路电压通常要低于三极管的阈值电压而需要借助外部电源供电等问题,本文提出了一种自供电的混合式同步电荷提取HSP-SECE(Hybrid Self-Powered Synchronous Electric Charge Extraction)电路。所提出的HSP-SECE电路,通过压电电压峰值的检测,在其达到峰值时进行压电振动能和温差热电能的同步提取,实现两种能量的融合采集。仿真和实验测试表明,所提出的电路可以有效实现温差热电能和压电振动能的同步采集,与现有的电路相比,在俘获效率、自供电和负载相关性等方面,具有较为明显的优势和特色。

Circuit design for harvesting piezoelectric energy and thermal energy existed in ambient energy harvesting has become one of the hot topics in recent years. However,since there are some issues such as energy types output from piezoelectric transducer(PZT)and thermoelectric generator(TEG)are in AC and DC,respectively,two different types of energy are hard to be simultaneously harvested and the open circuit voltage of the TEG normally is lower than the threshold voltage of the triode so that external power supply is required. In this paper,a hybrid self-powered synchronous electric charge extraction(HSP-SECE)circuit is presented. The proposed HSP-SECE circuit can simultaneously harvest energy from the PZT and TEG when the peak voltage of the PZT is detected through the passive peak detection circuit. Simulations and experiment tests show that HSP-SECE circuit can effectively harvest both piezoelectric energy and thermoelectric energy. Compared with the existing circuits,the proposed circuit has more advantages and characteristics in terms of harvesting efficiency,self-power,load correlation,etc.