A Self-Powered VDJT AC–DC Conversion Circuit for Piezoelectric Energy Harvesting Systems

Abstract

A comprehensive model for micro-powered piezoelectric generator (PG), analysis of operation, and control of voltage doubler joule thief (VDJT) circuit to find the piezoelectric devices (PD’s) optimum functioning points are discussed in the present article. The proposed model demonstrates the power dependence of the PG on mechanical excitation, frequency, and acceleration, as well as outlines the load behaviour for optimal operation. The proposed VDJT circuit integrates the combination of voltage doubler (VD) and joule thief circuit, whereas the VD circuit works in Stage 1 for AC (alternating current)–DC (direct current) conversion, while a joule thief circuit works in Stage 2 for DC–DC conversion. The proposed circuit functions as an efficient power converter, which converts power from AC–DC and boosts the voltage from low to high without employing any additional electronic components and generating duty cycles. The electrical nature of the input (i.e., PD) of a VDJT circuit is in perfect arrangement with the investigated optimisation needs when using the proposed control circuit. The effectiveness of the proposed VDJT circuit is examined in terms of both simulation and experiment, and the results are presented. The proposed circuit’s performance was validated with available results of power electronics interfaces in the literature. The proposed circuit’s flexibility and controllability can be used for various applications, including mobile battery charging and power harvesting.

Analysis of the Methods for Realization of Low-Power Piezoelectric Energy Harvesting Circuits for Wearable Battery-Free Power Supply Devices

“…In the last 2 years, various practical realizations of piezoelectric power conversion devices have been published [85,94,[99][100][101][102][103]. In this section, seven devices for piezoelectric energy harvesting are presented and compared.…”

“…The same author proposes another topology called voltage-doubler joule thief (VDJT) [103]. This concept is based on FBRJT topology but instead of a full-bridge rectifier a voltage doubler is used.…”

“…In the Table 3, a comparative representation of the investigated devices [85,94,[99][100][101][102][103]] is presented. The most important parameters such as the output power reached and/or the efficiency for each device are presented.…”