Self-Contained Resonant Rectifier for Piezoelectric Sources Under Variable Mechanical Excitation

Abstract

Abstract-A rectification scheme is proposed for increasing the available output power of electrical generators that have a high output capacitance. The proposed rectifier could be useful in increasing the output power of piezoelectric generators (PZG) that convert mechanical vibrations into electrical power. The improvement is achieved by a resonant circuit that self commutates the voltage across the output terminals of the PZG and thereby eliminates the shunting of the output current by the output capacitor. A low-consumption circuit synchronously controls the operation of the resonant rectifier by detecting voltage transitions across the generator. The presented resonant rectifier was experimentally verified by connecting it to a PZG as well as to a PZG emulator. The results show that, under constant harmonic excitation, the proposed circuit can significantly increase the extracted power by up to 230% as compared to a conventional bridge rectifier. The feasibility of using the proposed topology as a self-powered system driven by variable excitation was investigated experimentally as well. In particular, the system was driven by two types of excitation source: amplitude modulated and frequency modulated. It was found that the proposed circuit increases the extracted power by 160% and 172% for AM and FM excitations, respectively.

Resonant Rectifier ICs for Piezoelectric Energy Harvesting Using Low-voltage Drop Diode Equivalents

“…The results in [4], [6], [19] are based on discrete realization, which shows a high power [4] and a high PCE [19]. However, discrete realization may not suitable for mass production to accommodate a large number of sensors such as IoT.…”

“…However, we note that there exists power loss from the voltage drop of the two switches. To reduce the voltage drop, current paths for positive and negative cycles are split [4]- [6].…”

A direct AC-DC converter integrated with SSHI circuit for piezoelectric energy harvesting

“…Nevertheless, the controller for switch timing of the SSHI circuit is rather complex. In order to simply the controller for the switch timing, it inserts the diode into the resonant circuit [3,4,5]. Liao et al further simplify the controller by integrating a SSHI circuit with a full-bridge rectifier [6,7,8].…”

“…Liao et al further simplify the controller by integrating a SSHI circuit with a full-bridge rectifier [6,7,8]. However, the SSHI circuits reported in [1,2,3,4,5,6,7,8] are relied upon a low-frequency full-bridge rectifier. In fact, the full-bridge rectifier limits power extraction from the PE transducer.…”

Piezoelectric vibration energy harvesting: A connection configuration scheme to increase operational range and output power

“…The most commonly used passive rectification method is a full-bridge rectifier; however, this sets a high threshold voltage for the generated energy by the harvester to be transferred to a storage capacitor [Qian et al, 2013]. This limitation prevents the system from operating if the environmental excitation is not high enough to attain the required operational threshold voltage and the vibrational energy due to this small excitation is therefore not rectified and transferred to the energy storage device [Krihely and Ben-Yaakov, 2011]. Furthermore, for excitation resulting in harvester output slightly greater than the threshold 4 voltage, a very significant amount of energy is wasted as a result [Liang and Liao, 2012].…”