27 research outputs found

    Development of a Photovoltaic Array Emulator in a Real Time Control Environment Using xPC Target

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    Part 12: Integration of Power Electronics Systems with ICT - IIInternational audienceThis paper is devoted to the design and construction of a photovoltaic array emulator for high power applications in order to test all kind of photovoltaic inverters. To develop such device, a rapid prototyping tool based on xPC Target of Matlab/Simulink has been used, providing a real-time testing environment. PV array emulator can be used to evaluate the performance of photovoltaic inverters as any test conditions can be programmed. The proposed emulator operates as a distributed control system taking advantage of the TCP/IP protocol features

    A smart power electronic multiconverter for the residential sector

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    El futuro de la red incluye la generación distribuida y las tecnologías de red inteligente. Los sistemas de gestión del lado de la demanda (DSM) también serán esenciales para lograr un alto nivel de confiabilidad y robustez en los sistemas de energía. Para hacer eso, es necesario expandir la Infraestructura de medición avanzada (AMI) y los Sistemas de gestión de energía (EMS). La dirección de la tendencia es hacia la creación de centros de recursos energéticos, como el concepto de comunidad inteligente. Este documento presenta un sistema multiconvertidor inteligente para el sector residencial / vivienda con un Sistema de Almacenamiento de Energía Híbrido (HESS) que consta de supercapacitador y batería, y con integración de fuente de energía fotovoltaica (PV) local. El dispositivo funciona como una unidad de energía distribuida ubicada en cada casa de la comunidad, recibiendo puntos de ajuste de energía activos proporcionados por una comunidad inteligente EMS. Este SGA central es responsable de administrar los flujos de energía activa entre la red eléctrica, las fuentes de energía renovables, los equipos de almacenamiento y las cargas existentes en la comunidad. El multiconvertidor propuesto es responsable de cumplir con los puntos de referencia de potencia activa de referencia con la calidad de potencia adecuada; garantizando que los módulos fotovoltaicos locales funcionen con un algoritmo de seguimiento del punto de máxima potencia (MPPT); y prolongando la vida útil de la batería gracias a un funcionamiento cooperativo del HESS. Se ha desarrollado un modelo de simulación para mostrar el funcionamiento detallado del sistema. Finalmente, se implementó un prototipo de la plataforma de multiconversores y se realizaron algunas pruebas experimentales para validarlo.The future of the grid includes distributed generation and smart grid technologies. Demand Side Management (DSM) systems will also be essential to achieve a high level of reliability and robustness in power systems. To do that, expanding the Advanced Metering Infrastructure (AMI) and Energy Management Systems (EMS) are necessary. The trend direction is towards the creation of energy resource hubs, such as the smart community concept. This paper presents a smart multiconverter system for residential/housing sector with a Hybrid Energy Storage System (HESS) consisting of supercapacitor and battery, and with local photovoltaic (PV) energy source integration. The device works as a distributed energy unit located in each house of the community, receiving active power set-points provided by a smart community EMS. This central EMS is responsible for managing the active energy flows between the electricity grid, renewable energy sources, storage equipment and loads existing in the community. The proposed multiconverter is responsible for complying with the reference active power set-points with proper power quality; guaranteeing that the local PV modules operate with a Maximum Power Point Tracking (MPPT) algorithm; and extending the lifetime of the battery thanks to a cooperative operation of the HESS. A simulation model has been developed in order to show the detailed operation of the system. Finally, a prototype of the multiconverter platform has been implemented and some experimental tests have been carried out to validate it.Ministerio de Economía y Competitividad (España) y Fondos FEDER: Proyecto TEC2013-47316-C3-3-PpeerReviewe

    Fatal respiratory failure in a term newborn due to non-previously described compound heterozygous ABCA3 mutations

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    The adenosine triphosphate binding cassette member A3 (ABCA3) is a lipid transporter involved in pulmonary surfactant biogenesis. ABCA3 deficiency is increasingly being recognized as a cause of respiratory distress syndrome in term neonates. The clinical spectrum and severity of lung disease caused by ABCA3 mutations vary widely. We present a term newborn who presented respiratory distress short afterbirth. Despite treatment and supportive care, she developed a refractory progressive hypoxic respiratory failure and she died. She received repeated surfactant doses always with transient improvement. She was found to be a compound heterozygote for 2 non-previously described ABCA3 gene mutations, one inherited from each parent

    RICORS2040 : The need for collaborative research in chronic kidney disease

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    Chronic kidney disease (CKD) is a silent and poorly known killer. The current concept of CKD is relatively young and uptake by the public, physicians and health authorities is not widespread. Physicians still confuse CKD with chronic kidney insufficiency or failure. For the wider public and health authorities, CKD evokes kidney replacement therapy (KRT). In Spain, the prevalence of KRT is 0.13%. Thus health authorities may consider CKD a non-issue: very few persons eventually need KRT and, for those in whom kidneys fail, the problem is 'solved' by dialysis or kidney transplantation. However, KRT is the tip of the iceberg in the burden of CKD. The main burden of CKD is accelerated ageing and premature death. The cut-off points for kidney function and kidney damage indexes that define CKD also mark an increased risk for all-cause premature death. CKD is the most prevalent risk factor for lethal coronavirus disease 2019 (COVID-19) and the factor that most increases the risk of death in COVID-19, after old age. Men and women undergoing KRT still have an annual mortality that is 10- to 100-fold higher than similar-age peers, and life expectancy is shortened by ~40 years for young persons on dialysis and by 15 years for young persons with a functioning kidney graft. CKD is expected to become the fifth greatest global cause of death by 2040 and the second greatest cause of death in Spain before the end of the century, a time when one in four Spaniards will have CKD. However, by 2022, CKD will become the only top-15 global predicted cause of death that is not supported by a dedicated well-funded Centres for Biomedical Research (CIBER) network structure in Spain. Realizing the underestimation of the CKD burden of disease by health authorities, the Decade of the Kidney initiative for 2020-2030 was launched by the American Association of Kidney Patients and the European Kidney Health Alliance. Leading Spanish kidney researchers grouped in the kidney collaborative research network Red de Investigación Renal have now applied for the Redes de Investigación Cooperativa Orientadas a Resultados en Salud (RICORS) call for collaborative research in Spain with the support of the Spanish Society of Nephrology, Federación Nacional de Asociaciones para la Lucha Contra las Enfermedades del Riñón and ONT: RICORS2040 aims to prevent the dire predictions for the global 2040 burden of CKD from becoming true

    Sistema de inyección de energía cooperativo para plantas de generación fotovoltaica

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    Esta Tesis se ha elaborado con el fin de desarrollar un sistema de inyección de potencia de la energía procedente de una planta de generación fotovoltaica hacia la red general de distribución. La innovación que aporta la topología propuesta consiste en la asociación cooperativa de dos inversores, uno multinivel y otro tradicional, que consigue una óptima calidad de la potencia inyectada, a la vez que se mejora la eficiencia del conjunto. Primeramente, se realiza un estudio sobre el escenario actual de las fuentes de generación distribuida, para posteriormente fijar los objetivos buscados. Posteriormente, se realiza una revisión bibliográfica relativa a las topologías de inyección de energía fotovoltaica a red. Seguidamente, se mencionan los métodos empleados para las principales funciones asociadas a dichos sistemas, incluyendo el seguimiento del punto de máxima potencia, las técnicas de sincronización y el anti-islanding. Para desarrollar la topología propuesta, se hace un análisis de inversores de n niveles, profundizando en el inversor de 2 niveles y en el inversor de 3 niveles, incluyendo el estudio de pérdidas de ambos. Se propone una estructura de sincronización que mejora la robustez ante perturbaciones en la señal de entrada. Finalmente, se presenta la topología cooperativa monofásica y trifásica propuesta como sistema de inyección de potencia fotovoltaica conectado a red compuesta por un inversor de 3 niveles con diodos de clamping que se centra en inyectar la potencia y un inversor tradicional que se centra en controlar la calidad de la misma. La topología se valida con resultados experimentales.This document has been carried out with the goal of developing a power system to inject the energy of a photovoltaic plant into the grid. The innovation of the work consists in a proposed topology that relies on the cooperative association of two inverters, a multilevel and a traditional one, to improve the whole efficiency with higher power quality. Firstly, a present study about the distributed generation sources is done in order to set the general objectives. Later, an overview of the grid connected photovoltaic power injection systems is summarized from the literature. Next, the different methods of the basic functions associated to these systems, including the maximum power point tracking, the synchronization algorithm and the anti-islanding, are mentioned. The proposed topology is developed after an analysis of the n-level inverters, and specifically the two-level inverter and the neutral point clamped inverter, including the losses study of both converters. A grid synchronization method has been proposed too as a part of the control algorithm, which improves the response under distorted conditions. Finally, the cooperative topology proposed is presented, in its single-phase and three-phase structure, as a grid connected photovoltaic power injection system composed by a neutral point clamped that injects the power quantity term and a traditional inverter that controls the power quality term. The topology is validated through experimental results

    Sistema de inyección de energía cooperativo para plantas de generación fotovoltaica

    No full text
    Esta Tesis se ha elaborado con el fin de desarrollar un sistema de inyección de potencia de la energía procedente de una planta de generación fotovoltaica hacia la red general de distribución. La innovación que aporta la topología propuesta consiste en la asociación cooperativa de dos inversores, uno multinivel y otro tradicional, que consigue una óptima calidad de la potencia inyectada, a la vez que se mejora la eficiencia del conjunto. Primeramente, se realiza un estudio sobre el escenario actual de las fuentes de generación distribuida, para posteriormente fijar los objetivos buscados. Posteriormente, se realiza una revisión bibliográfica relativa a las topologías de inyección de energía fotovoltaica a red. Seguidamente, se mencionan los métodos empleados para las principales funciones asociadas a dichos sistemas, incluyendo el seguimiento del punto de máxima potencia, las técnicas de sincronización y el anti-islanding. Para desarrollar la topología propuesta, se hace un análisis de inversores de n niveles, profundizando en el inversor de 2 niveles y en el inversor de 3 niveles, incluyendo el estudio de pérdidas de ambos. Se propone una estructura de sincronización que mejora la robustez ante perturbaciones en la señal de entrada. Finalmente, se presenta la topología cooperativa monofásica y trifásica propuesta como sistema de inyección de potencia fotovoltaica conectado a red compuesta por un inversor de 3 niveles con diodos de clamping que se centra en inyectar la potencia y un inversor tradicional que se centra en controlar la calidad de la misma. La topología se valida con resultados experimentales.This document has been carried out with the goal of developing a power system to inject the energy of a photovoltaic plant into the grid. The innovation of the work consists in a proposed topology that relies on the cooperative association of two inverters, a multilevel and a traditional one, to improve the whole efficiency with higher power quality. Firstly, a present study about the distributed generation sources is done in order to set the general objectives. Later, an overview of the grid connected photovoltaic power injection systems is summarized from the literature. Next, the different methods of the basic functions associated to these systems, including the maximum power point tracking, the synchronization algorithm and the anti-islanding, are mentioned. The proposed topology is developed after an analysis of the n-level inverters, and specifically the two-level inverter and the neutral point clamped inverter, including the losses study of both converters. A grid synchronization method has been proposed too as a part of the control algorithm, which improves the response under distorted conditions. Finally, the cooperative topology proposed is presented, in its single-phase and three-phase structure, as a grid connected photovoltaic power injection system composed by a neutral point clamped that injects the power quantity term and a traditional inverter that controls the power quality term. The topology is validated through experimental results

    Apoptosis: implicaciones en Medicina Intensiva

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    El conocimiento de la muerte celular programada o apoptosis ha experimentado un enorme desarrollo en los últimos tiempos. Los hallazgos realizados implican cada vez más a este tipo de muerte celular con numerosas patologías, incluida la patología crítica. El objetivo de este trabajo es revisar el concepto de apoptosis y su importancia en la fisiopatología del paciente crítico. Los resultados obtenidos hasta la fecha demuestran que la apoptosis interviene en mayor o menor grado en la patogenia de innumerables enfermedades. El uso de bloqueadores de la apoptosis ha mostrado resultados satisfactorios en algunos modelos experimentales, mientras que en otros han sido contradictorios. Es posible que, en un futuro, el uso de medicamentos que permitan modular la apoptosis sea una alternativa terapéutica válida en este tipo de pacientes. Por ello es necesario profundizar en los mecanismos fisiopatológicos de la apoptosis en el paciente crític

    Increased numbers of circulating CD8 effector memory T cells before transplantation enhance the risk of acute rejection in lung transplant recipients.

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    The effector and regulatory T cell subpopulations involved in the development of acute rejection episodes in lung transplantation remain to be elucidated. Twenty-seven lung transplant candidates were prospectively monitored before transplantation and within the first year post-transplantation. Regulatory, Th17, memory and naïve T cells were measured in peripheral blood of lung transplant recipients by flow cytometry. No association of acute rejection with number of peripheral regulatory T cells and Th17 cells was found. However, effector memory subsets in acute rejection patients were increased during the first two months post-transplant. Interestingly, patients waiting for lung transplant with levels of CD8(+) effector memory T cells over 185 cells/mm(3) had a significant increased risk of rejection [OR: 5.62 (95% CI: 1.08-29.37), p=0.04]. In multivariate analysis adjusted for age and gender the odds ratio for rejection was: OR: 5.89 (95% CI: 1.08-32.24), p=0.04. These data suggest a correlation between acute rejection and effector memory T cells in lung transplant recipients. The measurement of peripheral blood CD8(+) effector memory T cells prior to lung transplant may define patients at high risk of acute lung rejection

    Three-Level Neutral-Point-Clamped Quasi-Z-Source Inverter with Maximum Power Point Tracking for Photovoltaic Systems

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    Part 12: Integration of Power Electronics Systems with ICT - IIInternational audienceThis article is focused on a photovoltaic system based on the three-level neutral-point-clamped quasi-z-source inverter. The maximum power point tracking (MPPT) algorithm based on dP/dV feedback was used in the photovoltaic system to adjust the duration of the shoot-through states of power switches and achieve a maximum power. Proper system operation in the case of irradiance step is demonstrated by simulation in Matlab/Simulink software
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