133 research outputs found
Células solares fotovoltaicas : desarrollo de sistemas de monitorización y seguimiento de sistemas fotovoltaicos
En la UMA se investiga tanto el control y análisis de este tipo de dispositivos, como en las características eléctricas de módulos de distintas tecnologías que ayudan, entre otras cosas, a conocer enn directo indicadores como la producción real de energía de estas plataformas
Characterisation of hourly temperature of a thin-film module from weather conditions by artificial intelligence techniques
The aim of this paper is the use and validation of artificial intelligence techniques to predict the
temperature of a thin-film module based on tandem CdS/CdTe technology. The cell temperature of a module is
usually tens of degrees above the air temperature, so that the greater the intensity of the received radiation, the greater
the difference between these two temperature values. In practice, directly measuring the cell temperature is very
complicated, since cells are encapsulated between insulation materials that do not allow direct access. In the literature
there are several equations to obtain the cell temperature from the external conditions. However, these models use
some coefficients which do not appear in the specification sheets and must be estimated experimentally. In this work,
a support vector machine and a multilayer perceptron are proposed as alternative models to predict the cell
temperature of a module. These methods allow us to achieve an automatic way to learn only from the underlying
information extracted from the measured data, without proposing any previous equation. These proposed methods
were validated through an experimental campaign of measurements. From the obtained results, it can be concluded
that the proposed models can predict the cell temperature of a module with an error less than 1.5 °C.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tec
Models for the Optimization and Evaluation of Photovoltaic Self-Consumption Facilities
The results obtained for the modeling and optimization of photovoltaic self-consumption facilities are presented. The study has been carried out for three Spanish cities with different climatic conditions. The self-consumption and self-sufficiency curves for different hourly consumption profiles have been obtained based on the installed peak power and the size of the battery. Different models of machine learning are proposed to predict these parameters. The input variables of these models are related to the configuration of the installation, its location and the type of consumption profile. The model with best predictions of self-sufficiency is Random Forest, which in cross-validation has a relative error of 5%. For the prediction of self-consumption, the model that performs best is the multilayer perceptron, with an average absolute error of 0.55 and an absolute relative error of 3%
New software tool to characterize photovoltaic modules from commercial equipment
A software platform has been developed in order to unify the different measurements obtained from different manufacturers in the
photovoltaic system laboratory of the University of Malaga, Spain. These measurements include the current-voltage curve of PV
modules and several meteorological parameters such as global and direct irradiance, temperature and spectral distribution of solar irradiance. The measurements are performed in an automated way by a stand-alone application that is able to communicate with a pair of multimeters and a bipolar power supply that are controlled in order to obtain the current–voltage pairs. In addition, several magnitudes, that can be configured by the user, such as irradiance, module temperature or wind speed, are incorporated to register the conditions of each measurement. Moreover, it is possible to attach to each curve the spectral distribution of the solar radiation at each moment. Independently of the source of the information, all these measurements are stored in a uniform relational database. These data can be accessed through a public web site that can generate several graphics from the data.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. Junta de Andalucía. Proyecto de Excelencia P11-RNM-711
Interfaz web para la gestión de sondas de red de altas prestaciones
A network probe is a device capable of capturing or injecting network traffic. This
work is founded on a custom-made FPGA based probe. So far, the only possibility to
interact with this probe was through the command line, difficulting the management of
the probe for people without any previous knowledge of it. Another issue present in the
probe’s control was the existence of many aspects related to its operation that were being
handled externally, such as storage, sorting and managing the traces or monitoring the
system performance.
The proposed application facilitates the use of the network probe through a web-based
graphical interface. This interface allows the user to manage the probe without any specific
knowledge of its inner workings. In addition, it brings together other relevant aspects of
the capture and injection of web traffic, such as trace storage, write speed of the disks or
trace format conversion. The interface implementation follows design that enables it to
be used on mobile devices with a similar user experience. The final product provides a
simple interface to manage all the relevant aspects of the probe, which displays the state
and additional information of the system visually, using graphs and statistics.
This project, however, has not exclusively consisted in the development of a graphical
interface. A base architecture, which formalizes the management of network probes from
a web interface, has also been designed. This proposal contemplates how to structure the
components so that it is extensible to other network probes, not just the one selected.
With this goal in mind, the system has been divided into two components, back-end
and front-end, which communicate with each other and that can be hosted on different
servers. Thereby, a REST Web Service has been designed and implemented for the backend,
which formalizes the status and functionality of the FPGA, adding also control over
other important aspects mentioned above. For the front-end, an ad hoc framework has
been created, which has served as a starting point for the web interface. It is intended
that most of the proposed solution could be reused in similar projects, in which the
management of the probes is done through command line.Una sonda de red es un dispositivo capaz de capturar tráfico de red o de inyectarlo.
Este trabajo está basado en una sonda a medida sobre una FPGA. Hasta ahora, la
única posibilidad era interaccionar con esta sonda desde la línea de comandos, lo que
dificultaba su gestión para personas sin conocimientos previos de la misma. Otro problema
presente en el control de la sonda era la existencia de numerosos aspectos relacionados
con su funcionamiento que se manejaban de forma externa, tales como el almacenamiento,
clasificación y gestión de las trazas, o la monitorización del rendimiento del sistema.
La aplicación propuesta facilita la utilización de la sonda de red mediante una interfaz
gráfica basada en tecnologías web. Esta interfaz permite gestionar la sonda sin tener un
conocimiento específico de su funcionamiento interno. También agrupa otros aspectos
relevantes de la captura y reproducción de tráfico web, como el almacenamiento de
las trazas, la velocidad de escritura en disco o la conversión entre formatos de traza.
La implementación de la interfaz sigue un diseño que permite que sea utilizada desde
dispositivos móviles con una experiencia de usuario similar. Se ha conseguido, como
producto final, una interfaz simple que permite gestionar todos los aspectos de la sonda
considerados relevantes, presentando el estado e información adicional del sistema de
forma visual, mediante gráficos y estadísticas.
Este proyecto, sin embargo, no ha consistido únicamente en el desarrollo de una
interfaz gráfica. Se ha diseñado también una arquitectura base que formaliza la gestión
de sondas de red desde una interfaz web. Esta propuesta contempla cómo estructurar los
componentes de forma que sea extensible a otras sondas de red, no solo la seleccionada.
Con este objetivo, se ha dividido el sistema en dos componentes, back-end y front-end, que
se comunican entre sí y que pueden estar alojados en un servidor distinto cada uno. Así, se
ha diseñado e implementado un ServicioWeb REST en el back-end, que formaliza el estado
y funcionalidad de la FPGA, añadiendo también control sobre otros aspectos relevantes
mencionados anteriormente. Para el front-end se ha creado un framework propio, que ha
servido de punto de partida para la interfaz web. Se pretende que gran parte de la solución
propuesta sea reutilizable en proyectos similares, en los que el manejo de las sondas se
realiza por línea de comandos
Optimization of Energy Distribution in Solar Panel Array Configurations by Graph Theory and Minkowski’s Paths
Nowadays, the development of the photovoltaic (PV) technology is consolidated as a source of renewable energy. The research in the topic of maximum improvement on the energy efficiency of the PV plants is today a major challenge. The main requirement for this purpose is to know the performance of each of the PV modules that integrate the PV field in real time.
In this respect, a PLC communications based Smart Monitoring and Communications Module, which is able to monitor at PV level their operating parameters, has been developed at the University of Malaga. With this device you can check if any of the panels is suffering any type of overriding performance, due to a malfunction or partial shadowing of its surface.
Since these fluctuations in electricity production from a single panel affect the overall sum of all panels that conform a string, it is necessary to isolate the problem and modify the routes of energy through alternative paths in case of PV panels array configuration.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech
Lexicon of ornaments in Murcian lists of goods of the Golden Age
[ES] El objetivo perseguido con este trabajo consiste en analizar una selección de voces referentes a guarniciones de piezas textiles, localizadas en relaciones de bienes, originales e inéditas, que se conservan en el Archivo Histórico Provincial de Murcia y que fueron redactadas en la zona de la Vega Alta del Segura (Murcia) durante el Siglo de Oro.[EN] The aim of this article is to analyze a selection of voices referring to ornaments of textile pieces, located in original and unpublished relations of goods. The documentation sources on which this article is based are kept in the Provincial Historical Archive of Murcia and were drafted in Vega Alta del Segura (Murcia) during the Spanish Golden Age
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