• Energy Research

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.

Abstract A novel maximum power point tracking algorithm for small wind turbines is proposed. The solution presented here is an adaptive intelligent algorithm that uses a new advanced perturb and observe method to search for the optimum relationship of the system for tracking the maximum power point even under variable wind conditions. The validity of the proposed algorithm is analysed and the design procedure is presented. Its main virtue resides in its capability to adapt to changes in the turbine and in the surrounding environment, even under variable wind conditions, improving the efficiency of the system. The experimental results confirm the validity of the proposed algorithm.

Critical systems require zero recovery time when a failure occurs in a communications network. The soon to be implemented standard IEC 62439-3 defines the only two protocols, parallel redundancy protocol and high-availability seamless redundancy, which fulfill this requirement and ensure no frame loss in the presence of an error. These protocols also provide a hot-plugging capability, which allows elements to be added to or removed from the network without interrupting communications and the operation of the plant. The electricity sector has adopted these for power utility automation in the recently published IEC 61850-90-4. The challenge is to obtain an efficient approach for use in electronic devices, capable of managing the characteristic duplicates, and circulating frames of these protocols, coupled with agile architectures capable of dealing with real-time processing requirements, fast switching times, high throughput, and deterministic behavior. The main contribution of this paper is the in-depth analysis it makes of network parameters imposed by the application of the protocols to power utility automation, and the proposition of a frame management system based on a segmented memory system that improves frame detecting time and uses the smallest memory required in order to resolve all the issues dealt with. Research and Education Unit of the Department of Electronics Technology, University of the Basque Country (UPV/EHU) (Grant Number: UFI11/16) Department of Education, Universities and Research of the Basque Government within the fund for Research Groups of Basque University System (Grant Number: IT394-10)

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.

Microgrids are a suitable, reliable and clean solution to integrate distributed generation into the mains grid. Microgrids can present both AC and DC distribution lines. The type of distribution conditions the performance of distribution line and implies different features, advantages and disadvantages in each case. This article analyses, in detail, all this parameters for AC and DC microgrids in order to identify and describe the available alternatives for building and configuring a microgrid. Elements and issues involved in the implementation and development, such as protections, power converters, economic analysis, availability, etc. are discussed and described. This analysis constitutes a tool for selecting a suitable configuration of a microgrid adapted to the needs in each situation. In addition, the article provides a picture of the current situation of microgrids, and identifies and proposes future research lines This workhasbeencarriedoutinsidetheResearchand Education UnitUFI11/16oftheUPV/EHUandsupportedbythe Department ofEducation,UniversitiesandResearchoftheBasque GovernmentwithinthefundforresearchgroupsoftheBasque universitysystemIT394-10andbytheGovernmentoftheBasque Country withintheresearchprogramETORTEKastheproject ENERGIGUNE12(IE12-335). This work has been carried out inside the Research and Education Unit UFI11/16 of the UPV/EHU and supported by the Department of Education, Universities and Research of the Basque Government within the fund for research groups of the Basque university system IT394-10 and by the Government of the Basque Country within the research program ETORTEK as the project ENERGIGUNE12 (IE12-335).

A large number of factors such as the increasingly stringent pollutant emission policies, fossil fuel scarcity and their price volatility have increased the interest towards the partial or total electrification of current vehicular technologies. These transition of the vehicle fleet into electric is being carried out progressively. In the last decades, several technological milestones have been achieved, which range from the development of basic components to the current integrated electric drives made of silicon (Si) based power modules. In this context, the automotive industry and political and social agents are forcing the current technology of electric drives to its limits. For example, the U.S Department of Energy’s goals for 2020 include the development of power converter technologies with power densities higher than 14.1 kW/kg and efficiencies greater than 98%. Additionally, target price of power converters has been set below $3.3/kW. Thus, these goals could be only achieved by using advanced semiconductor technologies. Wide-bandgap (WBG) semiconductors, and, most notably, silicon carbide (SiC) based power electronic devices, have been proposed as the most promising alternative to Si devices due to their superior material properties. As the power module is one of the most significant component of the traction power converter, this work focuses on an in-deep review of the state of the art concerning such element, identifying the electrical requirements for the modules and the power conversion topologies that will best suit future drives. Additionally, current WBG technology is reviewed and, after a market analysis, the most suitable power semiconductor devices are highlighted. Finally, this work focuses on practical design aspects of the module, such as the layout of the module and optimum WBG based die parallelization, placement and Direct Bonded Copper (DBC) routing. This work has been supported by the Department of Education, Linguistic Policy and Culture of the Basque Government within the fund for research groups of the Basque university system IT978-16, and by the Government of the Basque Country within the research program ELKARTEK as the project ENSOL (KK-2018/00040) and the Generalitat de Catalunya under AGAUR Grant 2017-SGR-1384. As well as, the program to support the education of researches of the Basque Country PRE_2017_2_0008.