Solid State Transformer with Integrated Input Stage

In this paper, a solid state transformer (SST) with integrated stages is addressed. The SST has been originally proposed for traction applications, after as an option to face the new requirements of the distributed generation but also suggested in many applications. There are different topologies, from one to three stages; certainly each one with their advantages and limitations. Some challenges for this type of systems are reducing the cost and increasing the efficiency.The components reduction is discussed in this paper, by integrating two stages of the SST; the ac/dc converter and the DAB converter share one leg. The proposed scheme is described and numerically simulated

Peak Current Control and Feed-Forward Compensation for the DAB Converter

This paper presents a double band peak current control for the DAB converter that permits to avoid the risk of transformer saturation. Additionally, feed-forward compensation is employed to achieve a fast transient response under load variations. The proposal is described, analyzed, and numerically simulated

Double Active Bridge Operated in Quasi Discontinuous Conduction Mode

The quasi discontinuous conduction mode (QDCM) of the double active bridge (DAB) is addressed in this paper. The DAB converter usually is operated turning on always two semiconductors per bridge, and this leads to a continuous inductor current: However, a similar operation to dc/dc converters can be implemented, for this, less than two switches are turned on, at certain time, in one of the bridges; this leads to the quasi-DCM. With this mode of operation, a natural soft-switching is performed during the whole range of operation, but also low current stress is performed compared to the square modulation, not only at low power range. The modulation is relatively simple compared to other techniques. The proposed technique is described, analyzed, numerically simulated, and experimentally tested

Multiwinding based Semi-Dual Active Bridge Converter

Modular converter structures are state of the art for fast charging, since high power and short charging times are required. Multiwinding converter structures can bring several positive advantages, like cost and space reduction. However, the increased complexity due to the magnetically coupled ports needs to be handled. This paper introduces a multiwinding based Semidual-Active-Bridge converter with separated output voltages. The related design challenges in terms of independent charging voltage regulation are evaluated and design guidelines for the medium frequency transformer are presented. The theoretical analysis is validated experimentally

Isolated Multiport Converter as Cost Efficient Solution for DC-Fast Charger of Electric Vehicle

The ongoing electrification of the transport sector raises demands for new power electronic solutions. As a consequence, modular converter structures are state of the art for fast charging, since high power and short charging times are required. This work presents a modular multiport DC-DC converter which has the capability to decrease the cost and size of the required charging station. Furthermore, design guidelines for the investigated topology are presented. The analysis is validated with a three port isolated DC-DC converter with separated loads

Indirect Modulation for Direct Matrix Converter

[ES] Los convertidores matriciales han sido estudiados y propuestos para diferentes aplicaciones.  Hay dos tipos de convertidores matriciales: los llamados indirectos y los directos, cada uno con sus ventajas y desventajas. Para el convertidor matricial indirecto se utilizan dos moduladores ya que está compuesto de dos etapas claramente definidas: un rectificador y un convertidor cd/ca; esto permite el uso de técnicas de modulación y control tradicionales. Por el contrario, el convertidor matricial directo se compone de una sola etapa, por lo que se considera un solo modulador o controlador; es decir que se usa un modulador directo.En este artículo se propone un modulador indirecto, pero para el convertidor matricial directo; esto es, se utilizan dos moduladores virtuales: un modulador para una etapa de entrada o rectificadora y otro para la etapa de salida o inversora; ciertamente ambos moduladores son unidos de forma que se generan las señales de control para el convertidor matricial de una sola etapa. Se presenta el análisis, operación y discusión de la propuesta, pero también resultados de simulación y experimentales que confirman la operación del sistema.[EN] Matrix converters have been studied and proposed for different applications. There are two types of matrix converters, the called indirect and direct converters, each one with their advantages and drawbacks. For the indirect matrix converter are considered two modulators since is composed by two stages: one for the rectifier stage and the other for the inverter stage, then a traditional controller should be employed; on the contrary the direct matrix converter is composed for just one stage, and then is considered a single modulator or controller, this is, a direct modulator is usually employed. In this paper an indirect modulation is addressed, but for the direct matrix converter; this is, two virtual modulators are employed; one modulator is for the input and the second for the output, but certainly both are joined to establish the final control signals of the single stage matrix converter. A comprehensive analysis, operation, and discussion is presented; but also simulation and some experimental results are presented to confirm the operation of the system.Este trabajo ha sido realizado gracias al apoyo del Tecnológico Nacional de México y del CONACyT (proyecto No. 293557).Vazquez, N.; Diosdado, R.; Huerta, H.; Osorio, R.; Vázquez, E.; Hernández, C. (2018). Modulación Indirecta para el Convertidor Matricial Directo. Revista Iberoamericana de Automática e Informática industrial. 15(3):317-326. https://doi.org/10.4995/riai.2018.8715OJS317326153Alesina A., Venturini M., 1981, "Solid-state power conversion: A Fourier analysis approach to generalized transformer synthesis," IEEE Trans. On Circuits Syst., CAS-28, pp. 319-330.Alesina A., Venturini M.G., 1989, Analysis and design of optimum-amplitude nine-switch direct AC-AC converters. IEEE Trans. on Power Electron., 4 (1), pp. 101-112.Blaabjerg F., Casadei D., Klumpner C., Matteini M., 2002, "Comparison of Two Current Modulation Strategies for Matrix Converters Under Unbalanced Input Voltage Conditions," IEEE Trans. Ind. Elect., 49(2), pp. 289-296.Boost M.A., Ziogas P.D., 1988, "State of the Art Carrier PWM Techniques: A critical evaluation," IEEE transactions on industry applications, 24 (2), pp. 271-280.Casadei D., Serra G., Tani A., Zarri L., 2002, "Matrix Converter Modulation Strategies: A New General Approach Based on Space-Vector Representation of the Switch State," IEEE Trans. Ind. Elect., 49(2), pp. 370-381.Chai M., Xiao D., Dutta R., Fletcher J.E., 2016, "Space Vector PWM Techniques for Three-to-Five-Phase Indirect Matrix Converter in the Overmodulation Region," IEEE Trans. Ind. Elect., 63(1), pp. 550-561.Ellabban O., Abu-Rub H., Bayhan S., 2016, "Z-Source Matrix Converter: An Overview," IEEE Trans. Power Electron., 31(11), pp. 7436-7450.Enjeti P.N., Choi S., 1993, "An approach to realize higher power PWM AC controller," In IEEE Applied Power Electronics Conference and Exposition, 1993, pp. 323-327.Hojabri H., Mokhtari H., Chang L., 2011, "A Generalized Technique of Modeling, Analysis, and Control of a Matrix Converter Using SVD," IEEE Trans. Ind. Elect., 58(3), pp. 949-959.Huber L., Borojevic D., 1995, "Space Vector Modulated Three-phase to Three-phase Matrix Converter with Input Power Factor Correction," IEEE Trans. on Ind. App., 31(6), pp. 1234-1246.Idris Z., Hamzah M.K., Omar A.M., 2005, "Implementation of Single-Phase Matrix Converter as a Direct AC-AC Converter Synthesized Using Sinusoidal Pulse Width Modulation with Passive Load Condition," IEEE PEDS.Nguyen T.D., Lee H.H., 2016, "Development of a Three-to-Five-Phase Indirect Matrix Converter with Carrier-Based PWM Based on Space-Vector Modulation Analysis," IEEE Trans. Ind. Elect., 63(1), pp. 13-24.Rashid M. H.. 2004, "Power Electronics: Circuits, devices, and applications". Ed. Pearson-Prentice Hall. 3rd EditionRatanapanachote S., Cha H.J., Enjeti P.N., 2006, "A Digitally Controlled Switch Mode Power Supply Based on Matrix Converter," IEEE Trans. Power Electron., 21(1), pp. 1818-1829, pp. 124-130.Riedemann J., Peña R., Cárdenas R., Blasco R., Clare J., 2014, "Indirect Matrix Converter Modulation Strategies for Open-end Winding Induction Machine," IEEE Latin America Trans., 12(3), pp. 395-401.Rivera M., Wilson A., Rojas C.A., Rodriguez J., Espinoza J.R., Wheeler P.W., Empringham L., 2013, "A Comparative Assessment of Model Predictive Current Control and Space Vector Modulation in a Direct Matrix Converter," IEEE Trans. Ind. Elect., 60 (2), pp. 578-588.Rodriguez J. J., Caporal R.M., Peralta E., Carranza O., Ortega R., 2016, "Optimal Venturini Modulation for a Three-phase Four-Wire Matrix Converter," IEEE Latin America Trans., 14(2), pp. 617-623.Rodriguez J., Rivera M., Kolar J.W., Wheeler P.W., 2012, "A Review of Control and Modulation Methods for Matrix Converters," IEEE Trans. Ind. Elect., 59 (1), pp. 58-69.Roy G., April G.E., 1989, "Cycloconverter operation under a new scalar control algorithm," in Proc. 20th Annu. IEEE Power Electron. Spec. Conf., vol. 1, pp. 368-375.Sayed M.A., Iqbal A., 2016, "Pulse width modulation technique for a three to-five phase matrix converter with reduced commutations," IET Power electronics, 9(3), pp. 466-475.Wheeler P.W., Rodríguez J., Clare J.C., Empringham L., Weinstein A., 2002, "Matrix Converters: A Technology Review," IEEE Trans. Ind. Elect., 49 (2), pp. 276-288.Venturini M., Alesina A., 1980, "The generalized transformer: A new bidirectional sinusoidal waveform frequency converter with continuously adjustable input power factor," in Proc. of IEEE PESC'80, pp. 242-252.Yoon Y.D., Sul S.K., 2006, "Carrier-Based Modulation Technique for Matrix Converter," IEEE Trans. Power Electron., 21(6), pp. 1691-1703.Ziogas P.D., Khan S.I., Rashid M.H., 1985, "Some Improved Forced Commutated Cycloconverter Structures," IEEE Trans. on Ind. App., IA-21(5), pp. 1242-1253.Ziogas P.D., Khan S.I., Rashid M.H., 1986, "Analysis and Design of Forced Commutated Cycloconverter Structures with Improved TransFer Characteristics," IEEE Trans. on Ind. Elect., IE-33(3), pp.271-280

Nuevo inversor fotovoltaico integrado sin transformador

Los inversores sin transformador son ampliamente utilizados en sistemas fotovoltaicos conectados a la red eléctrica, debido a los beneficios de lograr alta eficiencia y bajo costo.El inversor fotovoltaico sin transformador puede generar una corriente de fuga entre el inversor y la red eléctrica, a través de la capacitancia parásita del módulo fotovoltaico y la tierra física. Esta corriente de fuga provoca una disminución de la eficiencia, reduce el tiempo de vida del módulo fotovoltaico y pone en riesgo al personal que esté en contacto con el sistema. Se han propuesto varias topologías de inversores sin transformador para reducir esta corriente de fuga; este trabajo propone una topología diferente que consiste en la integración de dos etapas, un inversor puente completo y un convertidor CD/CD elevador. Una terminal de salida del inversor está conectada directamente a tierra y el convertidor es controlado por modos deslizantes.Palabra(s) Clave(s): control por modos deslizantes, corriente de fuga, inversor fotovoltaico

Search for dark matter produced in association with bottom or top quarks in √s = 13 TeV pp collisions with the ATLAS detector

A search for weakly interacting massive particle dark matter produced in association with bottom or top quarks is presented. Final states containing third-generation quarks and miss- ing transverse momentum are considered. The analysis uses 36.1 fb−1 of proton–proton collision data recorded by the ATLAS experiment at √s = 13 TeV in 2015 and 2016. No significant excess of events above the estimated backgrounds is observed. The results are in- terpreted in the framework of simplified models of spin-0 dark-matter mediators. For colour- neutral spin-0 mediators produced in association with top quarks and decaying into a pair of dark-matter particles, mediator masses below 50 GeV are excluded assuming a dark-matter candidate mass of 1 GeV and unitary couplings. For scalar and pseudoscalar mediators produced in association with bottom quarks, the search sets limits on the production cross- section of 300 times the predicted rate for mediators with masses between 10 and 50 GeV and assuming a dark-matter mass of 1 GeV and unitary coupling. Constraints on colour- charged scalar simplified models are also presented. Assuming a dark-matter particle mass of 35 GeV, mediator particles with mass below 1.1 TeV are excluded for couplings yielding a dark-matter relic density consistent with measurements