Odd-harmonic repetitive control of an active filter under varying network frequency: control design and stability analysis

This work deals with the design and analysis of a controller for a shunt active power filter. The design is based on combined feedforward and feedback actions, the last using repetitive control, and aims at the obtention of a good closedloop performance in spite of the possible frequency variations that may occur in the electrical network. As these changes affect the performance of the controller, the proposal includes a compensation technique consisting of an adaptive change of the digital controller’s sampling time according to the network frequency variation. However, this implies structural changes in the closed-loop system that may destabilize the overall system. Hence, this article is also concerned with closed-loop stability of the resulting system, which is analyzed using a robust control approach through the small gain theorem. Experimental results that indicate good performance of the closed-loop system are provided.Postprint (published version

Protocol d'actuació per al control i la prevenció de la tuberculosi en els immigrants i en els casos importats

Protocol d'actuació; Tuberculosi; ImmigrantsProtocolo de actuación; Tuberculosis; InmigrantesAction protocol; Tuberculosis; ImmigrantsAquest document és un protocol d'actuació per la tuberculosi i la seva prevenció

Efecto de una intervención formativa en urgencias en la mejora del manejo y el tratamiento de la insuficiencia cardiaca aguda.

Introducción y objetivos: Existe un escaso seguimiento de las recomendaciones de las guías de manejo diagnóstico y terapéutico de los pacientes con insuficiencia cardiaca aguda (ICA) en los servicios de urgencias hospitalarios (SUH). Se evalua si un programa de intervención sobre urgenciólogos permite mejorar el cumplimiento de estas guías. Método: Se diseñó un estudio de intervención cuasi-experimental sin grupo control y con una comparación pre y post-intervención. En una primera fase, se incluyeron de forma consecutiva a 708 pacientes que acudieron al SUH de 6 hospitales españoles durante un mes con el diagnóstico principal de ICA. En una segunda fase, se realizaron diferentes programas de formación sobre el manejo de la ICA según las guías vigentes. Tras la intervención, se volvió a incluir, siguiendo la misma metodología, a 613 pacientes que acudieron de ICA. Las variables principales fueron aquéllas que estudios previos habían detectado una mayor desviación de las recomendaciones de las principales guías (determinación de troponinas plasmáticas y BNP o pro-BNP, uso de furosemida en perfusión continua o nitroglicerina endovenosa y utilización de ventilación no invasiva-VNI). Resultados: Hubo escasas diferencias entre los grupos pre y postintervención en sus características demográficas, clínicas o en el tratamiento (en el grupo postintervención, existía un mayor porcentaje de pacientes con enfermedad cerebrovascular, neumopatía crónica, disfunción sistólica y tratamiento ambulatorio con bloqueadores beta-adrenérgicos; p < 0,05 para todos ellos). Se detectó un aumento significativo en la determinación de BNP o pro-BNP (incremento absoluto del 44,7%, IC del 95%: 39,9-49,5%; p < 0,001) y en el uso de nitroglicerina endovenosa (incremento absoluto del 6,9%, IC del 95%: 2,2-11,5; p < 0,01). Se evidenció un aumento no significativo en la determinación de troponinas, y en el uso de furosemida en perfusión continua y VNI. Conclusiones: Un programa de formación sobre el manejo diagnóstico y terapéutico de la ICA en los SUH mejora el seguimiento de las recomendaciones de las guías

Ultralight vector dark matter search using data from the KAGRA O3GK run

Among the various candidates for dark matter (DM), ultralight vector DM can be probed by laser interferometric gravitational wave detectors through the measurement of oscillating length changes in the arm cavities. In this context, KAGRA has a unique feature due to differing compositions of its mirrors, enhancing the signal of vector DM in the length change in the auxiliary channels. Here we present the result of a search for U(1)B−L gauge boson DM using the KAGRA data from auxiliary length channels during the first joint observation run together with GEO600. By applying our search pipeline, which takes into account the stochastic nature of ultralight DM, upper bounds on the coupling strength between the U(1)B−L gauge boson and ordinary matter are obtained for a range of DM masses. While our constraints are less stringent than those derived from previous experiments, this study demonstrates the applicability of our method to the lower-mass vector DM search, which is made difficult in this measurement by the short observation time compared to the auto-correlation time scale of DM

Differential response of planktonic primary, bacterial, and dimethylsulfide production rates to static vs. dynamic light exposure in upper mixed-layer summer sea waters

16 pages, 8 figures, 1 tableMicrobial plankton experience short-term fluctuations in total solar irradiance and in its spectral composition as they are vertically moved by turbulence in the oceanic upper mixed layer (UML). The fact that the light exposure is not static but dynamic may have important consequences for biogeochemical processes and ocean-atmosphere fluxes. However, most biogeochemical processes other than primary production, like bacterial production or dimethylsulfide (DMS) production, are seldom measured in sunlight and even less often in dynamic light fields. We conducted four experiments in oligotrophic summer stratified Mediterranean waters, where a sample from the UML was incubated in ultraviolet (UV)-transparent bottles at three fixed depths within the UML and on a vertically moving basket across the same depth range. We assessed the response of the phyto- and bacterioplankton community with physiological indicators based on flow cytometry singe-cell measurements, fast repetition rate fluorometry (FRRf), phytoplankton pigment concentrations and particulate light absorption. Dynamic light exposure caused a subtle disruption of the photoinhibition and photoacclimation processes associated with ultraviolet radiation (UVR), which slightly alleviated bacterial photoinhibition but did not favor primary production. Gross DMS production (GPDMS) decreased sharply with depth in parallel to shortwave UVR, and displayed a dose-dependent response that mixing did not significantly disrupt. To our knowledge, we provide the first measurements of GPDMS under in situ UV-inclusive optical conditions. © 2013 Author(s)M. G. acknowledges the receipt of a CSIC JAE scholarship. This work was supported by the (former) Spanish Ministry of Science and Innovation through the project SUMMER (CTM2008-03309/MAR). This is a contribution of the Research Groups on Marine Biogeochemistry and Global Change and on Aquatic Microbial Food Webs, supported by the Generalitat de CatalunyaPeer Reviewe

Odd-harmonic repetitive control of an active filter under varying network frequency: control design and stability analysis

This work deals with the design and analysis of a controller for a shunt active power filter. The design is based on combined feedforward and feedback actions, the last using repetitive control, and aims at the obtention of a good closedloop performance in spite of the possible frequency variations that may occur in the electrical network. As these changes affect the performance of the controller, the proposal includes a compensation technique consisting of an adaptive change of the digital controller’s sampling time according to the network frequency variation. However, this implies structural changes in the closed-loop system that may destabilize the overall system. Hence, this article is also concerned with closed-loop stability of the resulting system, which is analyzed using a robust control approach through the small gain theorem. Experimental results that indicate good performance of the closed-loop system are provided

Odd-harmonic repetitive control of an active filter under varying network frequency: a small-gain theorem-based stability analysis

Best Presentation in Session Award, que atorga la 2010 American Control ConferenceThis work deals with the design and analysis of a controller for a shunt active power filter. The design is based on combined feedforward and feedback actions, the last using repetitive control, and aims at the obtention of a good closedloop performance in spite of the possible frequency variations that may occur in the electrical network. As these changes affect the performance of the controller, the proposal includes a compensation technique consisting of an adaptive change of the digital controller’s sampling time according to the network frequency variation. However, this implies structural changes in the closed-loop system that may destabilize the overall system. Hence, this article is also concerned with closed-loop stability of the resulting system, which is analyzed using a robust control approach through the small gain theorem. Experimental results that indicate good performance of the closed-loop system are provided.Peer ReviewedAward-winnin

Robust high-order repetitive control of an active filter using an odd-harmonic internal model

Shunt active power filters have proven to be an efficient means to compensate for the negative effects of nonlinear and reactive loads on the power quality of the electrical distribution network. In this context, the control objective is to achieve a power factor close to 1, as well as load current harmonics and reactive power compensation. A useful control strategy for this purpose is repetitive control. However, the performance of repetitive controllers is strongly affected by frequency variations of the involved signals. This work analyzes the effect of such variations and describes the architecture of an odd-harmonic, high-order repetitive controller specifically designed to obtain robust closed-loop performance against frequency variations that may occur in the electrical network

Odd-harmonic repetitive control of an active filter under varying network frequency: a small-gain theorem-based stability analysis

Best Presentation in Session Award, que atorga la 2010 American Control ConferenceThis work deals with the design and analysis of a controller for a shunt active power filter. The design is based on combined feedforward and feedback actions, the last using repetitive control, and aims at the obtention of a good closedloop performance in spite of the possible frequency variations that may occur in the electrical network. As these changes affect the performance of the controller, the proposal includes a compensation technique consisting of an adaptive change of the digital controller’s sampling time according to the network frequency variation. However, this implies structural changes in the closed-loop system that may destabilize the overall system. Hence, this article is also concerned with closed-loop stability of the resulting system, which is analyzed using a robust control approach through the small gain theorem. Experimental results that indicate good performance of the closed-loop system are provided.Peer ReviewedAward-winningPostprint (published version