Feasibility study of a Medium Voltage DC/DC Converter adopting WBG devices

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Input Parallel Output Series Structure of Planar Medium Frequency Transformers for 200 kW Power Converter: Model and Parameters Evaluation

Nowadays, the demand for high power converters for DC applications, such as renewable sources or ultra-fast chargers for electric vehicles, is constantly growing. Galvanic isolation is mandatory in most of these applications. In this context, the Solid State Transformer (SST) converter plays a fundamental role. The adoption of the Medium Frequency Transformers (MFT) guarantees galvanic isolation in addition to high performance in reduced size. In the present paper, a multi MFT structure is proposed as a solution to improve the power density and the modularity of the system. Starting from 20 kW planar transformer model, experimentally validated, a multi- transformer structure is analyzed. After an analytical treatment of the Input Parallel Output Series (IPOS) structure, an equivalent electrical model of a 200 kW IPOS (made by 10 MFTs) is introduced. The model is validated by experimental measurements and tests

Fast hardware protection for a series-series compensated inductive power transfer system for electric vehicles

The paper proposes a simple solution to a safety problem encountered during the development of a series-series compensated IPT system for electric vehicles. This problem is related to the equivalent current source behavior of the receiver side in presence of an unpredicted load disconnection. A pure analog hardware system able to manage this fault protecting the filtering elements of the system is proposed. The system is investigated by means of a circuit simulation then its physical implementation is presented. The effectiveness of the proposed solution is experimentally proven

100 kW Three-Phase Wireless Charger for EV: Experimental Validation Adopting Opposition Method

This paper presents the experimental validation, using the opposition method, of a high-power three-phase Wireless-Power-Transfer (WPT) system for automotive applications. The systemunder test consists of three coils with circular sector shape overlapped to minimize the mutualcross-coupling, a three-phase inverter at primary side and a three-phase rectifier at receiver side.In fact thanks to the delta configuration used to connect the coils of the electromagnetic structure,a three-phase Silicon Carbide (SiC) inverter is driving the transmitter side. The resonance tankcapacitors are placed outside of the delta configuration reducing in this way their voltage sizing. ThisWPT system is used as a 100 kW–85 kHz ultrafast battery charger for light delivery vehicle directlysupplied by the power grid of tramways. The adopted test-bench for the WPT charger consistsof adding circulating boost converter to the system under test to perform the opposition methodtechnique. The experimental results prove the effectiveness of the proposed structure together withthe validation of fully exploited simulation analysis. This is demonstrated by transferring 100 kWwith more than94Ü-to-DC efficiency over 50 mm air gap in aligned conditions. Furthermore,testing of Zero-Current and Zero-Voltage commutations are performed to test the performance of SiCtechnology employed

Losses and thermal considerations on an IPOS structure with 20kW high-frequency planar transformers

Nowadays power electronics is looking for more integrated and compact insulated DC/DC converters. Electrical machines, like transformers, have a fundamental role in those kinds of converters. One of the main integration issue is the thermal aspect due to the power losses. Moreover, in an insulated DC/DC converter the bulkiest device is the transformer. Based on the high frequency power application the adopted transformer could be planar or litz wounded technology. In this work a single phase planar transformer for high power application has been investigated. An IPOS structure connecting many planar transformers has been performed to cope with the limitations that a single component gives. An experimental set-up adopting a SiC H-bridge power module feeding the different transformer structure. A power losses comparison among different structures has been realized. Indeed, the comparison is made connecting the H-bridge to a: single phase planar transformer, IPOS with 2 transformers, IPOS with 5 transformers, IPOS with 6 trans- formers and IPOS with a 10 transformers. The paper proposes thermal simulations for the IPOS made by 10 transformers and experimental result

Sensorless control of the charging process of a dynamic inductive power transfer system with interleaved nine-phase boost converter

The paper proposes a technique for the control of the charging process in a dynamic inductive power transfer system for automotive applications. This technique is based on an impedance control loop on the receiver side. The proposed control allows to carry out the different phases of the charging process in absence of a communication link between ground and vehicle side. The charging process starts with a sensorless procedure for the identification of the actual presence of the vehicle over the receiver. The same control technique introduces several advantages in terms of interoperability between systems having different requirements in terms of power demand. A 11 kW prototype has been implemented based on a transmitter 1.5 meters long as compromise solution between the long track coil and the lumped one. The power management of the receiver side is provided by a nine-phase interleaved boost converter. The experimental results prove the effectiveness of the proposed control together with a good matching with the developed theoretical equations set for the system description

Campaña de publicidad social "Mal Trago”

Trabajo Final para optar al grado académico de Licenciatura en Comunicación Social, Universidad Nacional de Córdoba. Calificación: 8 (ocho). Orientación AudiovisualEl presente trabajo es un Proyecto de Comunicación Aplicada que releva un tema social de actualidad como es el acoso sexual, del cual son víctimas principalmente las mujeres en los boliches bailables de la ciudad de Córdoba. El problema principal de esta tesis es tratar “la problemática del acoso sexual a mujeres dentro de los boliches de Córdoba Capital”. El objetivo de la construcción del producto es concientizar sobre el acoso a través de spots publicitarios dentro de los boliches y redes sociales. Por ende, decidimos abordarlo desarrollando una campaña de publicidad social y a través de una investigación cualitativa, realizando una recolección de datos y su posterior análisis. Es un tema dentro de la Violencia de Género de consideración pública en estos tiempos, en que la sociedad avanza en la igualdad de géneros, superando el modelo social patriarcal, vigente como hegemónico hasta principios del siglo XXI.Fil: Fandos, Jessica Belén. Universidad Nacional de Córdoba. Facultad de Ciencias de la Comunicación; Argentina.Fil: La Ganga, Julia Rina. Universidad Nacional de Córdoba. Facultad de Ciencias de la Comunicación; Argentina.Fil: Oviedo, Lautaro. Universidad Nacional de Córdoba. Facultad de Ciencias de la Comunicación; Argentina

Role of Microvesicles in the Spread of Herpes Simplex Virus 1 in Oligodendrocytic Cells

Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establishes latent infections in the neurons of sensory ganglia. In some cases, the virus spreads into the central nervous system, causing encephalitis or meningitis. Cells infected with several different types of viruses may secrete microvesicles (MVs) containing viral proteins and RNAs. In some instances, extracellular microvesicles harboring infectious virus have been found. Here we describe the features of shedding microvesicles released by the human oligodendroglial HOG cell line infected with HSV-1 and their participation in the viral cycle. Using transmission electron microscopy, we detected for the first time microvesicles containing HSV-1 virions. Interestingly, the Chinese hamster ovary (CHO) cell line, which is resistant to infection by free HSV-1 virions, was susceptible to HSV-1 infection after being exposed to virus-containing microvesicles. Therefore, our results indicate for the first time that MVs released by infected cells contain virions, are endocytosed by naive cells, and lead to a productive infection. Furthermore, infection of CHO cells was not completely neutralized when virus-containing microvesicles were preincubated with neutralizing anti-HSV-1 antibodies. The lack of complete neutralization and the ability of MVs to infect nectin-1/HVEM-negative CHO-K1 cells suggest a novel way for HSV-1 to spread to and enter target cells. Taken together, our results suggest that HSV-1 could spread through microvesicles to expand its tropism and that microvesicles could shield the virus from neutralizing antibodies as a possible mechanism to escape the host immune response. IMPORTANCE Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establishes latent infections in neurons. Extracellular vesicles are a heterogeneous group of membrane vesicles secreted by most cell types. Microvesicles, which are extracellular vesicles which derive from the shedding of the plasma membrane, isolated from the supernatant of HSV-1-infected HOG cells were analyzed to find out whether they were involved in the viral cycle. The importance of our investigation lies in the detection, for the first time, of microvesicles containing HSV-1 virions. In addition, virus-containing microvesicles were endocytosed into CHO-K1 cells and were able to actively infect these otherwise nonpermissive cells. Finally, the infection of CHO cells with these virus-containing microvesicles was not completely neutralized by anti-HSV-1 antibodies, suggesting that these extracellular vesicles might shield the virus from neutralizing antibodies as a possible mechanism of immune evasion

Recovering the Inflationary Potential

A procedure is developed for the recovery of the inflationary potential over the interval that affects astrophysical scales (\approx 1\Mpc - 10^4\Mpc). The amplitudes of the scalar and tensor metric perturbations and their power-spectrum indices, which can in principle be inferred from large-angle CBR anisotropy experiments and other cosmological data, determine the value of the inflationary potential and its first two derivatives. From these, the inflationary potential can be reconstructed in a Taylor series and the consistency of the inflationary hypothesis tested. A number of examples are presented, and the effect of observational uncertainties is discussed.Comment: 13 pages LaTeX, 6 Figs. available on request, FNAL-Pub-93/182-

The political economy of migration and reputation in Kinshasa

This essay presents a history of the mikiliste, the high-living bon vivant who travels to Europe and is a central figure in Kinois urban mythology. It looks in particular at the highly theatrical exchanges engaged in by the mikiliste, which relate especially to music patronage and to designer clothing. I show how these exchanges have evolved over time, both shaping and being shaped by the political economy of Kinshasa. The essay shows how such aesthetic performances should not be discussed in isolation from wider political-economic considerations. Those who participate in economies of prestige must be connected to a material base, and the ruling class, with their access to the resources of the interior, have become ever more important participants in the mikiliste rituals of largesse. Recently, theviolent contestation of mikiliste exchange, both in Europe and in Kinshasa, indicates that such moments of largesse may be involved in reproducing politicaleconomic relations in the Congolese capital