Advanced control of renewable energy microgrids with hybrid energy storage system

Renewable energy will play an important role in the transition to a new energetic model which, along with other developments of the digital age, will probably bring about the Third Industrial Revolution. However, the change to this new energetic model is subject to overcoming technological barriers, namely the sporadic nature of renewable sources. Which in turn affects both, power quality and economic competitiveness. The imbalance of active and reactive power that renewable energies introduce in the grid causes variation in the voltage supply, grid frequency, harmonics, as well as producing other power quality issues. Energy storage systems appear to be a key factor in compensating generation and demand. The lack of controllability and the penalty for deviations in the regulation market hinder the economic competitiveness of renewable energy. Energy storage systems will be the technological solution enabling controllability in renewable energies, allowing their introduction in the spot energy market. Redesigning the grid into smaller, more manageable units based on microgrids appears as a solution to the outlined problems. In these microgrids, stored energy compensates both the intermittent nature of renewable generation and the randomness of the consumer's behaviour. Traditionally, energy storage has been developed by large hydropower-regulation plants, however, these kinds of plants are subject to natural emplacements and their implementation is subject to environmental impact grades. The high energy density of hydrogen as an energy carrier will play an important role in this new energetic paradigm. However, robust performance and the transient response are the main barriers for its technological implantation and, usually, hydrogen-based systems have a useful life that is sometimes too limited to buffer the associated cost. Batteries and supercapacitors have a better transient response, however, their low energy density does not provide enough autonomy to the system. The design of a hybrid energy storage system, having advanced control systems in charge of taking advantage of each storage system and avoiding the causes of degradation and/or limitations of them, emerges as a technological solution to the problems commented. The high number of constraints and variables to be optimized increases the complexity of the associated control problem, making it necessary to deploy advanced control algorithms. In this thesis, the development of optimal controllers for renewable energy microgrids with hybrid energy storage systems is explored using Model Predictive Control (MPC). The control system is introduction on different time scales resulting in an optimal control solution for the economic dispatch and the power quality of the microgrid. Meanwhile, degradation issues of energy storage systems are analyzed and minimized, improving the longevity of the whole energy storage system

Incorporation of the intangibles into the spanish start-ups by activity sector and region. Improving their economic sustainability

Nowadays, start-ups, assuming increasing importance, have the possibility to include intangible knowledge as another resource on which they can carry out planning exercises, impact studies, evaluation and monitoring, protection, accumulation and exploitation. The study carried out in this paper allows us to analyze the influence that intangible knowledge has on the financial status of a start-up and, therefore, on its economic sustainability. This enables start-ups to present a good image, become more transparent, have more opportunities, reduce uncertainty, improve sustainability, etc. Moreover, the study presents a descriptive analysis of intangibles according to regions and activity sectors. An analysis of variance was carried out, to see if there is a relationship between the investment in intangible assets and the activity sector and/or regions to which the company belongs. The study concludes that, among all sectors, the differences in the incorporation of intangible assets into financial statements are most recognized in tourism, which may be a key factor for the sustainability of this sector, especially in periods of economic crisis, such as the one Europe and the planet are currently facin

A Stochastic MPC Based Energy Management System for Simultaneous Participation in Continuous and Discrete Prosumer-to-Prosumer Energy Markets

This article studies the exchange of self-produced renewable energy between prosumers (and with pure end consumers), through the discrete trading of energy packages and proposes a framework for optimizing this exchange. In order to mitigate the imbalances derived from discrepancies between production and consumption and their respective forecasts, the simultaneous continuous trading of instantaneous power quotas is proposed, giving rise to a time-ahead market running in parallel with a real-time one. An energy management system (EMS) based on stochastic model predictive control (SMPC) simultaneously determines the optimal bidding strategies for both markets, as well as the optimal utilisation of any energy storage system (ESS). Simulations carried out for a heterogeneous group of agents show that those with SMPC-EMS achieve savings of between 3% and 15% in their energy operation economic result. The proposed structures allows the peer-to-peer (P2P) energy trading between end users without ESS and constitute a viable alternative to avoid deviation penalties in secondary regulation markets.Ministerio de Economía y Competitividad ‘Retos Investigación 2016’ DPI2016-78338-

Further Remarks on Irrational Systems and Their Applications †

Irrational Systems (ISs) are transfer functions that include terms with irrational exponents. Since such systems are ubiquitous and can be seen when solving partial differential equations, fractional-order differential equations, or non-linear differential equations; their nature seems to be strongly linked with a low-order description of distributed parameter systems. This makes ISs an appealing option for model-reduction applications and controls. In this work, we review some of the fundamental concepts behind a set of ISs that are of core importance in their stability analysis and control design. Specifically, we introduce the notion of multivalued functions, branch points, time response, and stability regions, as well as some practical applications where these systems can be encountered. The theory is accompanied by some numerical examples or simulations

Power Quality Management of Interconnected Microgrids using Model Predictive Control

Cuenta con otro ed. : IFAC-PapersOnLine Incluida en el vol. 53 Article number: 145388In this paper, the power quality of interconnected microgrids is managed using a Model Predictive Control (MPC) methodology which manipulates the power converters of the microgrids in order to achieve the requirements. The control algorithm is developed for the microgrids working modes: grid-connected, islanded and interconnected. The results and simulations are also applied to the transition between the different working modes. In order to show the potential of the control algorithm a comparison study is carried out with classical Proportional-Integral Pulse Width Modulation (PI-PWM) based controllers. The proposed control algorithm not only improves the transient response in comparison with classical methods but also shows an optimal behavior in all the working modes, minimizing the harmonics content in current and voltage even with the presence of non-balanced and non-harmonic-free three-phase voltage and current systems.Ministerio de Economía y Competitividad (España) DPI2016-78338-RInterreg SUDOE SOE3 / P3 / E090

Microgrids Power Quality Enhancement Using Model Predictive Control

In electric power systems, any deviation with respect to the theoretical sinusoidal waveform is considered to be a disturbance in the power quality of the electrical grid. The deviation can alter any of the parameters of the waveform: frequency, amplitude, and symmetry among phases. Microgrid, as a part of the electric power system, has to contribute providing an adequate current waveform in grid connected-mode, as well as to guarantee similar voltage features than the standard requirement given for public distribution grids under normal exploitation conditions in islanded mode. Adequate power quality supply is necessary for the correct compatibility between all the devices connected to the same grid. In this paper, the power quality of microgrids is managed using a Model Predictive Control (MPC) methodology which regulates the power converters of the microgrids in order to achieve the requirements. The control algorithm is developed for the following microgrids working modes: grid-connected, islanded, and interconnected. The simulation results demonstrate that the proposed methodology improves the transient response in comparison with classical methods in all the working modes, minimizing the harmonic content in the current and the voltage even with the presence of non-balanced and non-harmonic-free three-phase voltage and current systems

Evaluation of the degradation of the graphene-polypropylene composites of masks in harsh working conditions

The recent COVID-19 outbreak has led health authorities to recommend at least the use of surgical masks, most preferably respirators (FFP2 or KN95), to prevent the spread of the virus. Non-woven fabrics have been chosen as the best option to manufacture the face masks, due to their filtration efficiency, low cost, and versatility. Modifying the mask filters with graphene has been of great interest due to its potential use as antibacterial and virucidal properties. Indeed, some companies have commercialized face masks in which graphene is coated and/or embedded. However, the Canadian sanitary authorities advised against using the Shandong Shengquan New Materials Co. graphene masks because of the possibility of pulmonary damage produced by graphene inhalation. Thus, we have analyzed the stability of the graphene filter of these masks and compared it with two other commercially available graphene mask filters, evaluating the morphological and spectroscopical change of the fibers, as well as the particles released during the endurance tests. Our work introduces the necessary tools and methodology to evaluate the potential degradation of face masks under extreme working conditions. These methods complement the present standard tests ensuring the security of the new filters based on composites or nanomaterialsWe thank Ministerio de Ciencia e Innovacion (projects PID2019- 106268GB-C31 and PID2019-106268GB-C32), the financial support through the “María de Maeztu” Programme for Units of Excellence in R&D (CEX2018-000805-M) and Banco de Santander CRUE (Fondo Supera COVID-19

Peroxidase expression in a cereal cyst nematode (Heterodera avenae) resistant hexaploid wheat line.

The incompatible interaction between plant and pathogen is often determined by the hypersensitive reaction (HR). This response is associated with accumulation of reactive oxygen species (ROS), which results in adverse growth conditions for pathogens. Two major mechanisms involving either NADPH oxidases or peroxidases have been proposed for generation of ROS. Peroxidases (PER, EC 1.11.1.7), present in all land plants, are members of a large multigenic family with high number of isoforms involved in a broad range of physiological processes. PER genes, which are expressed in nematode feeding sites, have been identified in several plant species (Zacheo et al. 1997). A strong correlation between HR and PER activities at four and seven days post nematode infection, was detected in roots of wheat lines carrying Cre2, Cre5 (from Ae. ventricosa) or Cre7 (from Ae. triuncialis) Heterodera avenae resistance genes (Andrés et al. 2001; Montes et al. 2003, 2004). We have studied changes in root of peroxidase mRNAs levels after infection by H. avenae of a wheat/Ae. ven¬tricosa introgression line (H-93-8) carrying Cre2 (Delibes et al. 1993). We also report and classify the predicted protein sequences derived from complete peroxidase transcripts

DRESS syndrome by sulfonamides, about a case

Among the most feared toxico-dermas is drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome, a rare drug dermatitis that occurs after acute exposure to drugs whose clinical impact is based on multiple organs (skin, liver, kidneys, lungs, heart) and cell lines (eosinophils and lymphocytes). It is an entity with high mortality if it is not identified early, its treatment consists of the immediate suspension of the responsible drug and the administration of steroids, these being the therapeutic protagonists. A 64-year-old male patient with clinical, biochemical and histopathological criteria compatible with DRESS syndrome. It is essential to suspect the clinical course of DRESS syndrome before the appearance of dermatosis with multisystem involvement associated with the use of drugs, emphasis is placed on its early identification and the establishment of timely treatment to modify its prognosis.

Functionalization of a Few-Layer Antimonene with Oligonucleotides for DNA Sensing

This document is the Accepted Manuscript version of a Published Work that appeared in final form in ACS Applied Nano Materials, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see: https://pubs.acs.org/doi/abs/10.1021/acsanm.0c00335Antimonene, a novel group 15 two-dimensional material, is functionalized with an oligonucleotide as a first step to DNA sensor development. The functionalization process leads to a few-layer antimonene modified with DNA that after deposition on gold screen-printed electrodes gives a simple and efficient DNA electrochemical sensing platform. We provide theoretical and experimental data of the DNA–antimonene interaction, confirming that oligonucleotides interact noncovalently but strongly with antimonene. The potential utility of this antimonene-based sensing device is assessed using, as a case of study, a sequence from the BRCA1 gene as the target DNA. The selectivity of the device allows not only recognition of a specific DNA sequence but also detection of a mutation in this gene associated with breast cancer, directly in clinical samplesThe Ministerio de Ciencia Innovación y Universidades (Grants CTQ2017-84309-C2-1-R, MAT2016-77608-C3-1-P, PCI2018-093081, JTC2017/2D-Sb&Ge, and FIS2016-80434-P), Generalitat Valenciana (Grant APOSTD/2017/010), and CAM (Grants TransNANOAVANSENS and 2017-T1/BIO-5435) are gratefully acknowledged. We also acknowledge the María de Maeztu Programme for Units of Excellence in R&D (MDM-2014-0377), the Fundación Ramón Areces, and the computer resources and assistance provided by the Centro de Computación Científica of the Universidad Autónoma de Madri