New controllability criteria for 3-phase 4-wire inverters applied to shunt active power filters

In shunt active filter applications, the 3-phase 4-wire topology is frequently used when dealing with unbalanced loads containing zero sequence components. A new design criteria for this topology is presented, based on the well-known existing method for the 3-phase 3-wire system. Simulation and experimental results confirms the validity of this new criteria, providing an easy method for the design of the reactive elements involved in a shunt active filter

Incremental SVM of controlled full-bridge rectifiers to allow IEC 61000-3-2 enforcement in power grid connection of modern elevator systems

The purpose of this paper is the study of different power converters and control techniques to allow power grid connection of modern vertical operation systems, verifying IEC 61000-3-2. We focus on the harmonic current analysis produced by the industrial standard AC/DC/3-phase AC machines system. Different AC/DC converters and control techniques have been compared to determine the one that minimizes low frequency harmonic current production. An incremental space vector modulator to regulate power grid current flow in electrical reference frame with a full-bridge controlled rectifier has been proven as the best power grid connection system. A general purpose test rig has been designed to evaluate the different power grid interface policies. Experimental results have been provided to show the effectiveness of the method

Experiencia PBL en una asignatura troncal de Electrónica general

El Congreso TAEE 2012, organizado por la Universidad de Vigo, se celebró entre el 13 y el 15 de junio de 2012La iniciación en la enseñanza relacionada con las tecnologías electrónicas en las diferentes titulaciones de ingeniería se ha venido realizando de manera habitual mediante la impartición de clases teóricas que plantean los conceptos básicos asociados a la electrónica analógica y digital. Este planteamiento se ha demostrado poco motivante para los alumnos, fundamentalmente porque no acerca los sistemas electrónicos reales a la clase. Para conseguir este acercamiento se ha rediseñado una asignatura troncal de electrónica general y 2º curso en el nuevo grado de Ingeniería en Tecnologías Industriales. La metodología docente planteada reduce el contenido de las clases teóricas del curso y mejora la coordinación entre la parte teórica y práctica de la asignatura mediante la inclusión en el temario de una metodología docente de aprendizaje basada en problema (PBL). En este artículo se detalla el programa de la asignatura y se describe la experiencia PBL desarrollada para la mismaUniversidad de Sevilla, I Plan Propio de Docenci

Análisis comparativo de diferentes técnicas de modulación PWM en convertidores de potencia

Buena parte del desarrollo y aplicación industrial de los convertidores de potencia se debe al avance experimentado en la generación de cualquier forma de onda de tensión deseada. La aparición de las técnicas de modulación, unido a la posibilidad de implementarlas en modernos microprocesadores o dispositivos electrónicos configurables (FPGA), ha favorecido el uso de los convertidores de potencia y el desarrollo industrial y comercial de propulsores eléctricos en vehículos, generadores eólicos, ascensores ecológicos, etc., por citar algunos ejemplos. Diferentes métodos de modulación, centrados en la generación de portadora o en la resolución analítica de un problema n-dimensional (modulación conocida como Space Vector Pulse Width Modulation o SVPWM), permiten que un convertidor de potencia imponga cualquier forma de onda de tensión que se desee a la carga a la que se encuentra conectado. Las diferentes estrategias de modulación se han ido complicando para lograr la mayor fiabilidad en la generación de la tensión deseada (menor ruido eléctrico). En este trabajo se analizan y comparan diferentes técnicas de modulación basadas en portadora o Space Vector, empleando herramientas de simulación basadas en Matlab y Simulink. El objetivo es plantear un análisis comparativo, que permita al alumno entender el interés y funcionamiento de cada técnica de modulación, observando las ventajas e inconvenientes asociadas

Hyperspectral image processing for the identification and quantification of lentiviral particles in fluid samples

Optical spectroscopic techniques have been commonly used to detect the presence of biofilm-forming pathogens (bacteria and fungi) in the agro-food industry. Recently, near-infrared (NIR) spectroscopy revealed that it is also possible to detect the presence of viruses in animal and vegetal tissues. Here we report a platform based on visible and NIR (VNIR) hyperspectral imaging for non-contact, reagent free detection and quantification of laboratory-engineered viral particles in fluid samples (liquid droplets and dry residue) using both partial least square-discriminant analysis and artificial feed-forward neural networks. The detection was successfully achieved in preparations of phosphate buffered solution and artificial saliva, with an equivalent pixel volume of 4 nL and lowest concentration of 800 TU.mu L-1. This method constitutes an innovative approach that could be potentially used at point of care for rapid mass screening of viral infectious diseases and monitoring of the SARS-CoV- 2 pandemic.This research was funded by grants number COV20-00080 and COV20-00173 of the 2020 Emergency Call for Research Projects about the SARS-CoV-2 virus and the COVID-19 disease of the Institute of Health 'Carlos III', Spanish Ministry of Science and Innovation, and by grant number EQC2019-006240-P of the 2019 Call for Acquisition of Scientific Equipment, FEDER Program, Spanish Ministry of Science and Innovation. This work has been supported by the European Commission through the JRC HUMAINT project. ABR was supported by grant number RTI2018-094465-J funded by the Spanish National Agency of Research. The authors would like to gratefully acknowledge the assistance of the members of the EOD-CBRN Group of the Spanish National Police, whose identities cannot be disclosed, and who are represented here by JMNG. Authors thank continuous support from their institutions

Polarimetric imaging for the detection of synthetic models of SARS-CoV-2: A proof of concept

Objective: To conduct a proof-of-concept study of the detection of two synthetic models of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using polarimetric imaging. Approach: Two SARS-CoV-2 models were prepared as engineered lentiviruses pseudotyped with the G protein of the vesicular stomatitis virus, and with the characteristic Spike protein of SARS-CoV-2. Samples were prepared in two biofluids (saline solution and artificial saliva), in four concentrations, and deposited as 5-µL droplets on a supporting plate. The angles of maximal degree of linear polarization (DLP) of light diffusely scattered from dry residues were determined using Mueller polarimetry from87 samples at 405 nm and 514 nm. A polarimetric camera was used for imaging several samples under 380–420 nm illumination at angles similar to those of maximal DLP. Per-pixel image analysis included quantification and combination of polarization feature descriptors in 475 samples. Main results: The angles (from sample surface) of maximal DLP were 3° for 405 nm and 6° for 514 nm. Similar viral particles that differed only in the characteristic spike protein of the SARS-CoV-2, their corresponding negative controls, fluids, and the sample holder were discerned at 10-degree and 15-degree configurations. Significance: Polarimetric imaging in the visible spectrum may help improve fast, non-contact detection and identification of viral particles, and/or other microbes such as tuberculosis, in multiple dry fluid samples simultaneously, particularly when combined with other imaging modalities. Further analysis including realistic concentrations of real SARS-CoV-2 viral particles in relevant human fluids is required. Polarimetric imaging under visible light may contribute to a fast, cost-effective screening of SARS-CoV-2 and other pathogens when combined with other imaging modalities.12 página

A test-rig to evaluate a wind turbine generation control system based on DSP

7th European Power Electronics Conference. Trondheim (Noruega), 8-10 Sept. 199

Contactless Ultrasonic Cavitation for the Prevention of Shunt Obstruction in Hydrocephalus: A Proof-of-Concept Study.

Obstructive failure of implanted shunts is the most common complication in the treatment of hydrocephalus. Biological material and debris accumulate in the inner walls of the valve and catheters block the normal flow of the drained cerebrospinal fluid causing severe symptoms with high morbidity and mortality. Unfortunately, at present, there is no effective preventive protocol or cleaning procedure available. To assess whether externally applied, focused ultrasound beams can be used to resuspend deposits accumulated in brain shunts safely. A computational model of an implanted brain shunt was implemented to test the initial design parameters of a system comprising several ultrasound transducers. Under laboratory conditions, configurations with 3 and 4 transducers were arranged in a triangle and square pattern with their radiation axis directed towards a target model of the device, 2 catheters and a brain shunt filled with water and deposited graphite powder. The ultrasound beams were then concentrated on the device across a head model. The computational model revealed that by using only 3 transducers, the acoustic field intensity on the valve was approximately twice that on the brain surface suggesting that acoustic cavitation could be selectively achieved. Resuspension of graphite deposits inside the catheters and the valve were then physically demonstrated and video-recorded with no temperature increase. The technology presented here has the potential to be used routinely as a noninvasive, preventive cleaning procedure to reduce the likelihood of obstruction-related events in patients with hydrocephalus treated with an implanted shunt

Hyperspectral image processing for the identification and quantification of lentiviral particles in fluid samples

Optical spectroscopic techniques have been commonly used to detect the presence of biofilm-forming pathogens (bacteria and fungi) in the agro-food industry. Recently, near-infrared (NIR) spectroscopy revealed that it is also possible to detect the presence of viruses in animal and vegetal tissues. Here we report a platform based on visible and NIR (VNIR) hyperspectral imaging for non-contact, reagent free detection and quantification of laboratory-engineered viral particles in fluid samples (liquid droplets and dry residue) using both partial least square-discriminant analysis and artificial feed-forward neural networks. The detection was successfully achieved in preparations of phosphate buffered solution and artificial saliva, with an equivalent pixel volume of 4 nL and lowest concentration of 800 TU·μ L−1. This method constitutes an innovative approach that could be potentially used at point of care for rapid mass screening of viral infectious diseases and monitoring of the SARS-CoV-2 pandemic.This research was funded by grants number COV20-00080 and COV20-00173 of the 2020 Emergency Call for Research Projects about the SARS-CoV-2 virus and the COVID-19 disease of the Institute of Health ‘Carlos III’, Spanish Ministry of Science and Innovation, and by grant number EQC2019-006240-P of the 2019 Call for Acquisition of Scientifc Equipment, FEDER Program, Spanish Ministry of Science and Innovation. This work has been supported by the European Commission through the JRC HUMAINT project. ABR was supported by grant number RTI2018-094465-J funded by the Spanish National Agency of Research

Optical imaging spectroscopy for rapid, primary screening of SARS-CoV-2: a proof of concept

Effective testing is essential to control the coronavirus disease 2019 (COVID-19) transmission. Here we report a-proof-of-concept study on hyperspectral image analysis in the visible and near-infrared range for primary screening at the point-of-care of SARS-CoV-2. We apply spectral feature descriptors, partial least square-discriminant analysis, and artificial intelligence to extract information from optical diffuse reflectance measurements from 5 µL fluid samples at pixel, droplet, and patient levels. We discern preparations of engineered lentiviral particles pseudotyped with the spike protein of the SARS-CoV-2 from those with the G protein of the vesicular stomatitis virus in saline solution and artificial saliva. We report a quantitative analysis of 72 samples of nasopharyngeal exudate in a range of SARS-CoV-2 viral loads, and a descriptive study of another 32 fresh human saliva samples. Sensitivity for classification of exudates was 100% with peak specificity of 87.5% for discernment from PCR-negative but symptomatic cases. Proposed technology is reagent-free, fast, and scalable, and could substantially reduce the number of molecular tests currently required for COVID-19 mass screening strategies even in resource-limited settings.This research was funded by Grants Number COV20-00080 and COV20-00173 of the 2020 Emergency Call for Research Projects about the SARS-CoV-2 virus and the COVID-19 disease of the Institute of Health ‘Carlos III’, Spanish Ministry of Science and Innovation, and by Grant Number EQC2019-006240-P funded by MICIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. ABR was supported by Grant Number RTI2018-094465-J-I00 funded by MICIN/AEI/10.13039/501100011033 and by “ERDF A way of making Europe”. This work has been supported by the European Commission through the Joint Research Center (JRC) HUMAINT project