Energy‐Harvesting Systems

Abstract

Research on energy-harvesting applications has gained importance in the last decade [1][2][3][4][5][6][7][8][9][10]. The most commonly discussed applications include wireless sensor nodes for healthcare, embedded or implanted sensor nodes for medical applications, tire pressure-monitoring systems for automobiles, battery-charging devices for long-sustainability systems, security or guard systems for homes, and environmental condition-monitoring systems. Figure 8.1 [11] shows a wireless healthcare bio-wireless sensor network (WSN) in a hospital used to monitor the vitals of patients [12]. Each patient wears several sensor nodes in several small monitoring systems, such as an electrocardiogram (ECG). Each system is responsible for specific physiological signals. The central health server can collect the sensed data through wireless communication.The popularity and widespread use of WSNs may be ascribed to several factors. The first factor is the progress of silicon technology in micrometer and even down to nanometer scales. According to Moore's law [13], the size of transistors on integrated circuits follows a decreasing trend of 0.7× every one and a half years. The gate count on a chip, as well as the operating speed and processing performance, increase significantly. The supply voltage on a silicon chip is also greatly reduced because of thinner oxides in advanced nanometer technologies. Smaller transistors or passive components result in lower parasitic effects and, thus, further reduce power loss. For a scale reduction by factor α (α > 1), the power consumption of a shrunk circuit that performs the same task can be reduced by (1/α) 3 [1]. The second factor is the progress of RF technology. RF technologies, especially low-power transmission networks such as Zigbee [14] and Bluetooth low energy (BLE) [15], facilitate data transmission and WSN construction. The third factor is the system integration of SoC and a heterogeneous system. A highly integrated SoC greatly decreases the requirements of external components, thereby reducing the volume and weight of the entire system. Heterogeneous integration technologies integrate Power Management Techniques for Integrated Circuit Design, First Edition. Ke-Horng Chen.

A Design of Boost Converter With Time-Domain MPPT and Digital Self-Tracking ZCD for Thermoelectric Energy Harvesting Applications

“…An energy harvesting boost converter extracts maximum power from energy sources such as solar or thermoelectric generators (TEG), according to MPPT operation. This paper presents a method that requires a reference voltage among various methods for MPPT operation, and this reference voltage is made by using the open circuit input voltage [3][4][5]. The open circuit input voltage is the boost converter's input voltage when the current dose not flow through the energy source.…”

Bio‐electrochemical response to sense implant degradation

“…Understanding degradation behaviour using state-of-theart techniques such as SVET, SECM and tribo-corrosion would significantly advance MBEC sensor technology. Emerging technologies in areas of energy harvesting such as piezoelectric harvesters(Chen, 2016;Elahi, Eugeni, & Gaudenzi, 2018), thermal harvesters(Wahbah, Alhawari, Mohammad, Saleh, & Ismail, 2014), electromagnetic harvesters, electrostatic harvesters and more recently triboelectric harvesters(Tanneru, Kuruvinashetti, Pillay, Rengaswamy, & Packirisamy, 2019) aim to fill the gap of powering the MBEC sensors for the duration of implant service life. Biocompatible microelectrodes, ultramicroelectrodes and nanoelectrodes will help in achieving miniaturization and reduction in power requirements to the milliwatt range.…”