Open Access
Presentación e inauguración de la Jornada
(2016) Carlosena García, Alfonso; López López, Hugo; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
El objetivo de la Jornada es dar a conocer las posibilidades de participación en acciones ERASMUS+ diferentes a la movilidad, entre otras: titulaciones de máster conjuntas Erasmus Mundus, asociaciones estratégicas en el ámbito de la educación, la formación y la juventud, alianzas para el conocimiento y alianzas para las competencias sectoriales, desarrollo de las capacidades en el ámbito de la educación superior, acciones Jean Monnet, cátedras, módulos, centros de excelencia, apoyo a asociaciones, redes y proyectos, actividades deportivas.
Open Access
V Jornadas de Enseñanza de las Matemáticas en Navarra: acto de apertura
(2018) Carlosena García, Alfonso; Solana Arana, María; Jiménez, Jesús Javier; Fernández Pérez, David; Lasa Oyarbide, Aitzol; Ingeniería Eléctrica, Electrónica y de Comunicación; Estadística, Informática y Matemáticas; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Estatistika, Informatika eta Matematika
Open Access
Ultra-low frequency multidirectional harvester for wind turbines
(Elsevier, 2023) Castellano Aldave, Jesús Carlos; Carlosena García, Alfonso; Iriarte Goñi, Xabier; Plaza Puértolas, Aitor; Ingeniería; Ingeniería Eléctrica, Electrónica y de Comunicación; Institute of Smart Cities - ISC; Ingeniaritza; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this paper we propose, and demonstrate through a prototype, a completely novel device able to harvest mechanical energy from the multidirectional vibrations in a wind turbine, and convert it into electrical, to power autonomous sensors. The application is very challenging since vibrations are of ultra-low frequency, well below 1 Hz, with accelerations of tenths of cm/s2 (0.01 g), and the device must capture energy from the movement in any direction. According to our experiments, the device is capable to generate average powers around the milliwatt in the operation conditions of a wind turbine, which are enough for some very-low power sensor nodes, or at least to considerably extend the life-time of batteries. The device is based on the principle of moving (inertial) masses comprised of magnets in Hallbach arrays interacting with coils, and can work for movements on any direction of a plane. To the best of our knowledge, this is the first device specifically proposed for wind turbines and one of the few that work in such low frequencies, and capture energy from movements on any direction on a plane. Only three harvesters proposed in the literature, intended for distinct applications, can work at such low frequencies, and our device exhibits a better efficiency. Though comparisons with harvesters working in different contexts and, even using different conversion principles, is not completely fair, we make in this paper a comparison to the closest ones, resorting to two different figures of merit.
Open Access
A family of alternating current amplifiers for ultra-low frequency operation
(Wiley, 2021) Martincorena Arraiza, Maite; Carlosena García, Alfonso; Cruz Blas, Carlos Aristóteles de la; Beloso Legarra, Javier; López Martín, Antonio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
A family of capacitively coupled alternating current (AC) amplifiers featuring ultra-low (below 1 Hz) corner frequency is presented. This is achieved by using high-gain devices which actively boost feedback resistance and thus reduce corner frequency. This procedure is often termed, though with a different purpose, as 'bootstrapping'. The proposed architectures are very general and admit several possible practical implementations. To demonstrate their usefulness, the circuits are implemented with two operational amplifiers (OA), but other active devices such as operational transconductance amplifiers (OTAs) can be alternatively used. All circuits have been theoretically analyzed, extensively simulated and measured, exhibiting high-pass cutoff frequencies as low as 30 mHz.
Open Access
Señales y espectros: buscando los ciclos de la naturaleza
(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2023) Carlosena García, Alfonso; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
Se explica qué es la teoría de la señal.
Open Access
Dataset for the identification of a ultra-low frequency multidirectional energy harvester for wind turbines
(Elsevier, 2024-11-20) Bacaicoa Díaz, Julen; Hualde Otamendi, Mikel; Merino Olagüe, Mikel; Plaza Puértolas, Aitor; Iriarte Goñi, Xabier; Castellano Aldave, Jesús Carlos; Carlosena García, Alfonso; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Ingeniería; Ingeniaritza; Institute of Smart Cities - ISC; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This paper presents a publicly available dataset designed to support the identification (characterization) and performance optimization of an ultra-low-frequency multidirectional vibration energy harvester. The dataset includes detailed measurements from experiments performed to fully characterize its dynamic behaviour. The experimental data encompasses both input (acceleration)-output (energy) relationships, as well as internal system dynamics, measured using a synchronized image processing and signal acquisition system. In addition to the raw input-output data, the dataset also provides post-processed information, such as the angular positions of the moving masses, their velocities and accelerations, derived from recorded high-speed videos at 240 Hz. The dataset also includes the measured power output generated in the coils. This dataset is intended to enable further research on vibration energy harvesters by providing experimental data for identification, model validation, and performance optimization, particularly in the context of energy harvesting in low-frequency and multidirectional environments, such as those encountered in wind turbines.
Open Access
Low-frequency electromagnetic harvester for wind turbine vibrations
(Elsevier, 2024) Castellano Aldave, Jesús Carlos; Plaza Puértolas, Aitor; Iriarte Goñi, Xabier; Carlosena García, Alfonso; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC; Ingeniería; Ingeniaritza; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
In this paper we describe and fully characterize a novel vibration harvester intended to harness energy from the vibration of a wind turbine (WT), to potentially supply power to sensing nodes oriented to structural health monitoring (SHM). The harvester is based on electromagnetic conversion (EM) and can work with vibrations of ultra-low frequencies in any direction of a plane. The harvester bases on a first prototype already disclosed by the authors, but in this paper, we develop an accurate model parameterized by a combination of physical parameters and others related to the geometry of the device. The model allows predicting not only the power generation capabilities, but also the kinematic behaviour of the harvester. Model parameters are estimated by an identification procedure and validated experimentally. Last, the harvester is tested in real conditions on a wind turbine.
Open Access
Modal frequency and damping estimation of wind turbines: analysis of a wind farm
(Springer, 2024-06-22) Legaz Catena, Asier; Zivanovic, Miroslav; Iriarte Goñi, Xabier; Plaza Puértolas, Aitor; Carlosena García, Alfonso; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC; Ingeniería; Ingeniaritza
In this paper, we present an in-depth analysis carried out on several units of the same Wind Turbine (WT) model installed in a wind farm. We have collected simultaneous data under several different operating conditions ranging from the idling state to nominal power close to cut-out. Both frequency and damping parameters have been estimated for the first and second Fore-Aft (FA) and Side-Side (SS) tower modes. As far as we know, there are no previous publications combining data from so many turbines, operating conditions, and for a time period spanning several months. We have made use of a novel strategy to isolate the modes and minimize the influence of harmonics, using an algorithm previously proposed by the authors. The main conclusion is that estimated modal frequencies allow for a clear discrimination between turbines, whereas damping ratios, subjected to much wider deviations, do not seem to be very discriminant. We show here results for only one operating mode (nominal power), for which the method has been tuned. The analysis of other operating modes and longer periods, now under consideration, will allow for more conclusive results.
Open Access
A novel ultra-low input voltage and frequency self astarting AC-DC boost converter for micro energy harvesting
(IEEE, 2024) Castellano Aldave, Jesús Carlos; Cruz Blas, Carlos Aristóteles de la; Carlosena García, Alfonso; Ingeniería Eléctrica, Electrónica y de Comunicación; Ingeniaritza Elektrikoa, Elektronikoa eta Telekomunikazio Ingeniaritza; Institute of Smart Cities - ISC
In this letter, a novel low-voltage junction field-effect transistor (JFET) oscillator with self-starting capability to implement an ac-dc boost converter is introduced. The circuit is transformer free and can operate with very low-voltage and low-frequency signals. In order to operate with positive and negative input signals, a coupled topology of JFETs has been used. The circuit has been built using off the shelf components, and can be used with electromagnetic harvesters, thermoelectric modules, and/or wearable devices. Experimental results with a practical harvester are provided in order to demonstrate the proposed ac-dc boost converter.
Open Access
AC coupled amplifier with a resistance multiplier technique for ultra-low frequency operation
(Elsevier, 2022) Martincorena Arraiza, Maite; Cruz Blas, Carlos Aristóteles de la; Carlosena García, Alfonso; López Martín, Antonio; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; Ingeniería Eléctrica, Electrónica y de Comunicación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
This paper proposes a novel, tunable AC coupled capacitive feedback amplifier, exhibiting an ultra-low high pass corner frequency. This is accomplished by actively boosting the output resistive value of a MOS transistor in weak inversion. The circuit is based on a more general architecture, recently proposed by the authors, and is analyzed in terms of its capability to achieve ultra-low frequency operation, its DC performance, and noise. The proposed technique is demonstrated via measurement results from a fabricated test chip prototype using a standard 0.18 µm CMOS technology. The proposed amplifier provides a tunable high pass corner frequency from 20 mHz to 475 mHz, consuming 4.71 μW and a total area of 0.069 mm2.