A Self-Powered Dual-Stage Boost Converter Circuit for Piezoelectric Energy Harvesting Systems

Abstract

Miniaturised piezoelectric devices are emerging energy harvesting sources that are appropriate for various implantable and wearable applications. However, these piezoelectric devices exhibit considerable internal resistance due to their internal impedance, which leads to self-start and low-energy conversion failures. This paper describes a dual-stage boost converter circuit by facilitating self-powering features and boosting the low voltage harvested by the piezoelectric devices into dc. The proposed circuit comprises conversion stages of ac-dc and dc-dc in Stages I and II, respectively. In addition, the proposed circuit does not require employing the auxiliary circuits to generate the train pulses by triggering the bidirectional switches to envelop the current being stored in Stage II and kick-start the self-powered circuit for piezoelectric energy harvesting systems. Theoretical assumptions and control strategies were tested and verified with ideal and impedance input sources. The proposed circuit could convert a low voltage of 3 Vac into 19 Vdc. The maximum attained output power by the proposed circuit was 3.61 mW. The outcome depicted that the proposed circuit boosted the low voltage and outperformed the existing literature circuits in terms of output voltage and power.

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 first selected work [101] was developed by M. Elda et al and represents a nonlinear switching circuit (INLSC) for the active rectification of voltage in a piezoelectric energy harvesting (PEH) system. The proposed schematic is presented in Figure 35.…”

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

“…Alternately, it also can be considered as voltage in series with its internal capacitor, C P [5,24,[34][35][36]. The internal characteristics of the PG in AC voltage (i.e., positive and negative cycles) are explained below and depicted in Figure 3b [5,8,9,11,[37][38][39][40][41][42].…”

“…As a result, the VD circuit's output voltage is doubled and stored in the load capacitor, C L1 . The VD circuit's output power varies with rectified voltage [11,43], and the optimum power output occurs when [5,8,9,11,[37][38][39][40][41][42]:…”

“…In practice, PGs are confined to low-power domains in the micro/milliwatt category caused by physically constrained features like internal capacitance and resistance [1][2][3][4]. They can withstand extremely high pressure but have minimal strain and make huge material quantities challenging to use [5][6][7][8][9]. In contrast, most anticipated excitations are generally in the range of 0.1 to 1 kHz and produce low voltage levels, whereas most electronic equipment requires 3 to 5 V dc.…”