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UrsĂșa Rubio, Alfredo

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UrsĂșa Rubio

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Alfredo

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Ingeniería Eléctrica, Electrónica y de Comunicación

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ISC. Institute of Smart Cities

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0000-0001-6240-8659

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3245

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Now showing 1 - 10 of 28
  • PublicationOpen Access
    Influence of the aging model of lithium-ion batteries on the management of PV self-consumption systems
    (IEEE, 2018) Berrueta Irigoyen, Alberto; Pascual Miqueleiz, Julio MarĂ­a; San MartĂ­n Biurrun, Idoia; Sanchis GĂșrpide, Pablo; UrsĂșa Rubio, Alfredo; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; IngenierĂ­a ElĂ©ctrica, ElectrĂłnica y de ComunicaciĂłn; Gobierno de Navarra / Nafarroako Gobernua, PI038 INTEGRA-RENOVABLES
    Lithium-ion batteries are gaining importance for a variety of applications due to their improving characteristics and decreasing price. An accurate knowledge of their aging is required for a successful use of these ESSs. The vast number of models that has been proposed to predict these phenomena raise doubts about the suitability of a model for a particular battery application. The performance of three models published for a Sanyo 18650 cylindrical cell in a self-consumption system are compared in this work. Measured photovoltaic production and home consumption with a sampling frequency of 15 minutes are used for this comparison. The different aging predictions calculated by these three models are analyzed, compared and discussed. These comparison is particularized for two management strategies. The first of them maximizes the self-consumption PV energy, while the second reduces the maximum power peak demanded from the grid.
  • PublicationOpen Access
    Comparison of State-of-Charge estimation methods for stationary Lithium-ion batteries
    (IEEE, 2016) Berrueta Irigoyen, Alberto; San MartĂ­n Biurrun, Idoia; Sanchis GĂșrpide, Pablo; UrsĂșa Rubio, Alfredo; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC
    An accurate monitoring of the State of Charge (SoC) is mandatory for an efficient management of a Lithium-ion battery. Batteries of stationary systems barely have long resting periods when the cumulative errors can be reset. These special requirements make a robust and accurate SoC estimation algorithm necessary. A real stationary system including an experimental microgrid with renewable energy generation, home consumption and a 5.3 kWh Li-ion storage system is analyzed in this paper. Three representative SoC monitoring algorithms are applied and compared in terms of accuracy and robustness to battery aging and current measurement offset. A closed-loop method consisting of an adaptive filter and a state observer achieves best results while having a reasonable computational complexity.
  • PublicationOpen Access
    Electro-thermal modelling of a supercapacitor and experimental validation
    (Elsevier, 2014) Berrueta Irigoyen, Alberto; San MartĂ­n Biurrun, Idoia; HernĂĄndez, Andoni; UrsĂșa Rubio, Alfredo; Sanchis GĂșrpide, Pablo; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
    This paper reports on the electro-thermal modelling of a Maxwell supercapacitor (SC), model BMOD0083 with a rated capacitance of 83 F and rated voltage of 48 V. One electrical equivalent circuit was used to model the electrical behaviour whilst another served to simulate the thermal behaviour. The models were designed to predict the SC operating voltage and temperature, by taking the electric current and ambient temperature as input variables. A five-stage iterative method, applied to three experiments, served to obtain the parameter values for each model. The models were implemented in MATLABSimulink , where they interacted to reciprocally provide information. These models were then validated through a number of tests, subjecting the SC to different current and frequency profiles. These tests included the validation of a bank of supercapacitors integrated into an electric microgrid, in a real operating environment. Satisfactory results were obtained from the electric and thermal models, with RMSE values of less than 0.65 V in all validations.
  • PublicationOpen Access
    High frequency power transformers with foil windings: maximum interleaving and optimal design
    (IEEE, 2015) Barrios RĂ­podas, Ernesto; Urtasun Erburu, Andoni; UrsĂșa Rubio, Alfredo; Marroyo Palomo, Luis; Sanchis GĂșrpide, Pablo; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Ingeniaritza Elektrikoa eta Elektronikoa; Universidad PĂșblica de Navarra / Nafarroako Unibertsitate Publikoa
    Foil conductors and primary and secondary interleaving are normally used to minimize winding losses in high frequency transformers used for high-current power applications. However, winding interleaving complicates the transformer assembly, since taps are required to connect the winding sections, and also complicates the transformer design, since it introduces a new tradeoff between minimizing losses and reducing the construction difficulty. This paper presents a novel interleaving technique, named maximum interleaving, that makes it possible to minimize the winding losses as well as the construction difficulty. An analytical design methodology is also proposed in order to obtain free cooled transformers with a high efficiency, low volume and, therefore, a high power density. For the purpose of evaluating the advantages of the proposed maximum interleaving technique, the methodology is applied to design a transformer positioned in the 5 kW 50 kHz intermediate high frequency resonant stage of a commercial PV inverter. The proposed design achieves a transformer power density of 28 W/cm3 with an efficiency of 99.8%. Finally, a prototype of the maximum-interleaved transformer is assembled and validated satisfactorily through experimental tests.
  • PublicationOpen Access
    Influence of the power supply on the energy efficiency of an alkaline water electrolyser
    (Elsevier, 2009) UrsĂșa Rubio, Alfredo; Marroyo Palomo, Luis; GubĂ­a Villabona, Eugenio; GandĂ­a Pascual, Luis; DiĂ©guez Elizondo, Pedro; Sanchis GĂșrpide, Pablo; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Ingeniaritza Elektrikoa eta Elektronikoa; IngenierĂ­a MecĂĄnica, EnergĂ©tica y de Materiales; Mekanika, Energetika eta Materialen Ingeniaritza; QuĂ­mica Aplicada; Kimika Aplikatua; Gobierno de Navarra / Nafarroako Gobernua
    Electric energy consumption represents the greatest part of the cost of the hydrogen produced by water electrolysis. An effort is being carried out to reduce this electric consumption and improve the global efficiency of commercial electrolysers. Whereas relevant progresses are being achieved in cell stack configurations and electrodes performance, there are practically no studies on the effect of the electric power supply topology on the electrolyser energy efficiency. This paper presents an analysis on the energy consumption and efficiency of a 1 N m3 h1 commercial alkaline water electrolyser and their dependence on the power supply topology. The different topologies of power supplies are first summarised, analysed and classified into two groups: thyristor-based (ThPS) and transistor-based power supplies (TrPS). An Electrolyser Power Supply Emulator (EPSE) is then designed, developed and satisfactorily validated by means of simulation and experimental tests. With the EPSE, the electrolyser is characterised both obtaining its I–V curves for different temperatures and measuring the useful hydrogen production. The electrolyser is then supplied by means of two different emulated electric profiles that are characteristic of typical ThPS and TrPS. Results show that the cell stack energy consumption is up to 495 W h N m3 lower when it is supplied by the TrPS, which means 10% greater in terms of efficiency.
  • PublicationOpen Access
    Boost DC-AC inverter: a new control strategy
    (IEEE, 2005) Sanchis GĂșrpide, Pablo; UrsĂșa Rubio, Alfredo; GubĂ­a Villabona, Eugenio; Marroyo Palomo, Luis; IngenierĂ­a ElĂ©ctrica, ElectrĂłnica y de ComunicaciĂłn; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren
    Boost dc–ac inverter naturally generates in a single stage an ac voltage whose peak value can be lower or greater than the dc input voltage. The main drawback of this structure deals with its control. Boost inverter consists of Boost dc–dc converters that have to be controlled in a variable-operation point condition. The sliding mode control has been proposed as an option. However, it does not directly control the inductance averaged-current. This paper proposes a control strategy for the Boost inverter in which each Boost is controlled by means of a double-loop regulation scheme that consists of a new inductor current control inner loop and an also new output voltage control outer loop. These loops include compensations in order to cope with the Boost variable operation point condition and to achieve a high robustness to both input voltage and output current disturbances. As shown by simulation and prototype experimental results, the proposed control strategy achieves a very high reliable performance, even in difficult transient situations such as nonlinear loads, abrupt load changes, short circuits, etc., which sliding mode control cannot cope with.
  • PublicationOpen Access
    On the testing, characterization, and evaluation of PV inverters and dynamic MPPT performance under real varying operating conditions
    (Wiley, 2007) Sanchis GĂșrpide, Pablo; LĂłpez Taberna, JesĂșs; UrsĂșa Rubio, Alfredo; GubĂ­a Villabona, Eugenio; Marroyo Palomo, Luis; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Ingeniaritza Elektrikoa eta Elektronikoa; Gobierno de Navarra / Nafarroako Gobernua
    The increasing number of photovoltaic inverters that are coming on to the PV marketstresses the need to carry out a dynamic characterization of these elements and theirmaximum power point tracking (MPPT) algorithms under real operating conditions.In order to make these conditions repeatable at the laboratory, PV array simulatorsare used. However, actual simulators, including the commercial simulators, recreateonly a single or small set of PV array characteristic curves in which quite commonlytheoretical calculations are included in order to simulate irradiance and temperatureartificial variations. This is far from being a recreation of the real and long dynamicbehavior of a PVarray or generator. The testing and evaluation of the performance ofPV inverters and MPPT algorithms has to be carried out when the PV system movesdynamically according to real operating conditions, including processes such asrapidly changing atmospheric conditions, partial shadows, dawn, and nightfall. Thispaper tries to contribute to the analysis of this problem by means of an electronicsystem that both measures the real evolution of the characteristic curves of PVarraysat outdoor operation and then recreates them at the laboratory to test PV inverters.This way the equipment can highlight the different performances of PV inverters andMPPT techniques when they operate under real operating conditions. As an example,two commercial inverters are tested and analyzed under the recreated behavior of aPV generator during 2 singular days that include processes of partial shading and fastirradiance variations.
  • PublicationOpen Access
    A comprehensive model for lithium-ion batteries: from the physical principles to an electrical model
    (Elsevier, 2018) Berrueta Irigoyen, Alberto; Urtasun Erburu, Andoni; UrsĂșa Rubio, Alfredo; Sanchis GĂșrpide, Pablo; Ingeniaritza Elektrikoa eta Elektronikoa; Institute of Smart Cities - ISC; IngenierĂ­a ElĂ©ctrica y ElectrĂłnica; Gobierno de Navarra / Nafarroako Gobernua, PI038 INTEGRA-RENOVABLES
    The growing interest in e-mobility and the increasing installation of renewable energy-based systems are leading to rapid improvements in lithium-ion batteries. In this context, battery manufacturers and engineers require advanced models in order to study battery performance accurately. A number of Li-ion battery models are based on the representation of physical phenomena by electrochemical equations. Although providing detailed physics-based information, these models cannot take into account all the phenomena for a whole battery, given the high complexity of the equations. Other models are based on equivalent circuits and are easier to design and use. However, they fail to relate these circuit parameters to physical properties. In order to take the best of both modeling techniques, we propose an equivalent circuit model which keeps a straight correlation between its parameters and the battery electrochemical principles. Consequently, this model has the required simplicity to be used in the simulation of a whole battery, while providing the depth of detail needed to identify physical phenomena. Moreover, due to its high accuracy, it can be used in a wide range of environments, as shown in the experimental validations carried out in the final section of this paper.
  • PublicationOpen Access
    Critical comparison of energy management algorithms for lithium-ion batteries in renewable power plants
    (IEEE, 2019) Berrueta Irigoyen, Alberto; Soto Cabria, AdriĂĄn; GarcĂ­a Solano, Miguel; Parra Laita, ĂĂ±igo de la; Sanchis GĂșrpide, Pablo; UrsĂșa Rubio, Alfredo; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; IngenierĂ­a ElĂ©ctrica, ElectrĂłnica y de ComunicaciĂłn; Universidad PĂșblica de Navarra / Nafarroako Unibertsitate Publikoa
    Lithium-ion batteries are gaining importance for a variety of applications due to their price decrease and characteristics improvement. A good energy management strategy is required in order to increase the profitability of an energy system using a Li-ion battery for storage. The vast number of management algorithms that has been proposed to optimize the achieved profit, with diverse computational power requirements and using models with different complexity, raise doubts about the suitability of an algorithm and the required computation power for a particular application. The performance of three energy management algorithms based on linear, quadratic, and dynamic programming are compared in this work. A realistic scenario of a medium-sized PV plant with a constraint of peak shaving is used for this comparison. The results achieved by the three algorithms are compared and the grounds of the differences are analyzed. Among the three compared algorithms, the quadratic one seems to be the most suitable for renewableenergy applications, given the undue simplification of the battery aging required by the linear algorithm and the discretization and computational power required by a dynamic algorithm.
  • PublicationOpen Access
    Influence of renewable power fluctuations on the lifetime prediction of lithium-ion batteries in a microgrid environment
    (IEEE, 2019) Soto Cabria, AdriĂĄn; Berrueta Irigoyen, Alberto; Sanchis GĂșrpide, Pablo; UrsĂșa Rubio, Alfredo; Ingeniaritza Elektrikoa, Elektronikoaren eta Telekomunikazio Ingeniaritzaren; Institute of Smart Cities - ISC; IngenierĂ­a ElĂ©ctrica, ElectrĂłnica y de ComunicaciĂłn; Gobierno de Navarra / Nafarroako Gobernua
    This contribution analyses lifetime estimation errors due to the effect of power fluctuations in lithium-ion batteries connected to microgrids when different time steps are used for the calculations. Usually, not every second data are available or the computational cost is excessively high. Those facts result in the use of larger time steps. However, the increase of the time steps may turn out in too optimistic predictions. Data from a real microgrid make it possible to optimize calculation times while keeping low errors. The results show that when 1 minute time step is set, the computation time is reduced by 14.4 times while the lifetime overstatement is only 3.5-5.2% higher, depending on the aging model.