As worldwide awareness about global climate change spreads, green electronics are becoming increasingly popular as an alternative to diminish pollution. Thus, nowadays energy efficiency is a paramount characteristic in electronics systems to obtain such a goal. Harvesting wasted energy from human activities and world physical phenomena is an alternative to deal with the aforementioned problem. Energy harvesters constitute a feasible solution to harvesting part of the energy being spared. The present research work provides the tools for characterizing, designing and implementing such devices in electronic systems through their equivalent structural models.
The present research work proposes a photovoltaic energy harvester and an appropriate direct current (DC)/DC converter for a harvesting system after the study of the devices and taking the operation conditions. Parameters such as power, efficiency and voltage are taken into account under different environment conditions of illumination and temperature in order to obtain the best possible response. For this reason, suitable metal-oxide semiconductor field-effect transistor (MOSFET), diode, coil, frequency, duty-cycle and load are selected and analyzed for a DC/DC converter with boost architecture.
The smart-grid concept takes the communications from the enclosed and protected environment of a substation to the wider city or nationwide area. In this environment, cyber security takes a key role in order to secure the communications. The challenge is to be able to secure the grid without impacting the latency while, at the same time, maintaining compatibility with older devices and non secure services. At the lower level, added security must not interfere with the redundancy and the latency required for the real-time substation automation communications. This paper studies how to integrate IEEE MAC Security standard (MACsec) in the substation environment, especially when used in substation system communications
Nowadays, system-on-chips have become critical since they support more and more safe applications due to their flexibility. However, they are susceptible to single-event upsets because the memory cell size has significantly shrunk. This article presents a triple redundant on-chip interconnect bus that provides low-speed peripherals with high reliability. In addition to correcting single errors and detecting duplicated ones, the proposed circuit offers zero latency and is transparent for both the embedded processor and the peripherals. These characteristics make it suitable for hard real-time applications. At the same time, the impact on area and power consumption is minimal.
Wind energy harvesting is a widespread mature technology employed to collect energy, but it is also suitable, and not yet fully exploited at small scale, for powering low power electronic systems such as Internet of Things (IoT) systems like structural health monitoring, on-line sensors, predictive maintenance, manufacturing processes and surveillance. The present work introduces a three-phase mini wind energy harvester and an Alternate Current/Direct Current (AC/DC) converter. The research analyzes in depth a wind harvester’s operation principles in order to extract its characteristic parameters. It also proposes an equivalent electromechanical model of the harvester, and its accuracy has been verified with prototype performance results. Moreover, unlike most of the converters which use two steps for AC/DC signal conditioning—a rectifier stage and a DC/DC regulator—this work proposes a single stage converter to increase the system efficiency and, consequently, improve the energy transfer. Moreover, the most suitable AC/DC converter architecture was chosen and optimized for the best performance taking into account: the target power, efficiency, voltage levels, operation frequency, duty cycle and load required to implement the aforementioned converter.