The key to self-powered technique is initiative to harvest energy from the surrounding environment. Harvesting energy from an ambient vibration source utilizing piezoelectrics emerged as a popular method. Effi- cient ...The key to self-powered technique is initiative to harvest energy from the surrounding environment. Harvesting energy from an ambient vibration source utilizing piezoelectrics emerged as a popular method. Effi- cient interface circuits become the main limitations of existing energy harvesting techniques. In this paper, an inter- face circuit for piezoelectric energy harvesting is presented. An active full bridge rectifier is adopted to improve the power efficiency by reducing the conduction loss on the rectifying path. A parallel synchronized switch harvesting on inductor （P-SSHI） technique is used to improve the power extraction capability from piezoelectric harvester, thereby trying to reach the theoretical maximum output power. An intermittent power management unit （IPMU） and an output capacitor-less low drop regulator （LDO） are also introduced. Active diodes （AD） instead of tradition- al passive ones are used to reduce the voltage loss over the rectifier, which results in a good power efficiency. The IPMU with hysteresis comparator ensures the interface circuit has a large transient output power by limiting the output voltage ranges from 2.2 to 2 V. The design is fabricated in a SMIC 0.18/~m CMOS technology. Simulation results show that the flipping efficiency of the P-SSHI circuit is over 80% with an off-chip inductor value of 820/zH. The output power the proposed rectifier can obtain is 44.4/~W, which is 6.7x improvement compared to the maximum output power of a traditional rectifier. Both the active diodes and the P-SSHI help to improve the output power of the proposed rectifier. LDO outputs a voltage of 1.8 V with the maximum 90% power efficiency. The proposed P-SSHI rectifier interface circuit can be self-powered without the need for additional power supply.展开更多
基金Project supported by the National Natural Science Foundation of China(Nos.61574103,U1709218)the Key Research and Development Program of Shaanxi Province(No.2017ZDXM-GY-006)
文摘The key to self-powered technique is initiative to harvest energy from the surrounding environment. Harvesting energy from an ambient vibration source utilizing piezoelectrics emerged as a popular method. Effi- cient interface circuits become the main limitations of existing energy harvesting techniques. In this paper, an inter- face circuit for piezoelectric energy harvesting is presented. An active full bridge rectifier is adopted to improve the power efficiency by reducing the conduction loss on the rectifying path. A parallel synchronized switch harvesting on inductor （P-SSHI） technique is used to improve the power extraction capability from piezoelectric harvester, thereby trying to reach the theoretical maximum output power. An intermittent power management unit （IPMU） and an output capacitor-less low drop regulator （LDO） are also introduced. Active diodes （AD） instead of tradition- al passive ones are used to reduce the voltage loss over the rectifier, which results in a good power efficiency. The IPMU with hysteresis comparator ensures the interface circuit has a large transient output power by limiting the output voltage ranges from 2.2 to 2 V. The design is fabricated in a SMIC 0.18/~m CMOS technology. Simulation results show that the flipping efficiency of the P-SSHI circuit is over 80% with an off-chip inductor value of 820/zH. The output power the proposed rectifier can obtain is 44.4/~W, which is 6.7x improvement compared to the maximum output power of a traditional rectifier. Both the active diodes and the P-SSHI help to improve the output power of the proposed rectifier. LDO outputs a voltage of 1.8 V with the maximum 90% power efficiency. The proposed P-SSHI rectifier interface circuit can be self-powered without the need for additional power supply.
