Towards a More Flexible, Sustainable, Efficient and Reliable Induction Cooking: A Power Semiconductor Device Perspective

Esta tesis tiene como objetivo fundamental la mejora de la flexibilidad, sostenibilidad, eficiencia y fiabilidad de las cocinas de inducción por medio de la utilización de dispositivos semiconductores de potencia: Dentro de este marco, existe una funcionalidad que presenta un amplio rango de mejora. Se trata de la función de multiplexación de potencia, la cual pretende resolverse de una manera más eficaz por medio de la sustitución de los comúnmente utilizados relés electromecánicos por dispositivos de estado sólido. De entre todas las posibles implementaciones, se ha identificado entre las más prometedoras a aquellas basadas en dispositivos de alta movilidad de electrones (HEMT) de Nitruro de Galio (GaN) y de aquellas basadas en Carburo de Silicio (SiC), pues presentan unas características muy superiores a los relés a los que se pretende sustituir. Por el contrario, otras soluciones que inicialmente parecían ser muy prometedoras, como los MOSFETs de Súper-Unión, han presentado una serie de comportamientos anómalos, que han sido estudiados minuciosamente por medio de simulaciones físicas a nivel de chip. Además, se analiza en distintas condiciones la capacidad en cortocircuito de dispositivos convencionalmente empleados en cocinas de inducción, como son los IGBTs, tratándose de encontrar el equilibrio entre un comportamiento robusto al tiempo que se mantienen bajas las pérdidas de potencia. Por otra parte, también se estudia la robustez y fiabilidad de varios GaN HEMT de 600- 650 V tanto de forma experimental como por medio de simulaciones físicas. Finalmente se aborda el cálculo de las pérdidas de potencia en convertidores de potencia resonantes empleando técnicas de termografía infrarroja. Por medio de esta técnica no solo es posible medir de forma precisa las diferentes contribuciones de las pérdidas, sino que también es posible apreciar cómo se distribuye la corriente a nivel de chip cuando, por ejemplo, el componente opera en modo de conmutación dura. Como resultado, se obtiene información relevante relacionada con modos de fallo. Además, también ha sido aprovechar las caracterizaciones realizadas para obtener un modelo térmico de simulación.This thesis is focused on addressing a more flexible, sustainable, efficient and reliable induction cooking approach from a power semiconductor device perspective. In this framework, this PhD Thesis has identified the following activities to cover such demands: In view of the growing interest for an effective power multiplexing in Induction Heating (IH) applications, improved and efficient Solid State Relays (SSRs) as an alternative to the electromechanical relays (EMRs) are deeply investigated. In this context, emerging Gallium Nitride (GaN) High‐Electron‐Mobility Transistors (GaN HEMTs) and Silicon Carbide (SiC) based devices are identified as potential candidates for the mentioned application, featuring several improved characteristics over EMRs. On the contrary, other solutions, which seemed to be very promising, resulted to suffer from anomalous behaviors; i.e. SJ MOSFETs are thoroughly analysed by electro‐thermal physical simulations at the device level. Additionally, the Short Circuit (SC) capability of power semiconductor devices employed or with potential to be used in IH appliances is also analysed. On the one hand, conventional IGBTs SC behavior is evaluated under different test conditions so that to obtain the trade‐off between ruggedness and low power losses. Moreover, ruggedness and reliability of several normally‐off 600‐650 V GaN HEMTs are deeply investigated by experimentation and physics‐based simulation. Finally, power losses calculation at die‐level is performed for resonant power converters by means of using Infrared Thermography (IRT). This method assists to determine, at the die‐level, the power losses and current distribution in IGBTs used in resonant soft‐switching power converters when functioning within or outside the Zero Voltage Switching (ZVS) condition. As a result, relevant information is obtained related to decreasing the power losses during commutation in the final application, and a thermal model is extracted for simulation purposes.<br /

Comparación de la regresión Poisson y la regresión de Cox: aplicación al estudio de la incapacidad permanente en una cohorte de 768.454 trabajadores afiliados a la Seguridad Social

Este proyecto quiere cumplir dos objetivos: uno, de metodología estadística (objetivo 1) y el otro, de salud pública (objetivo 2). En concreto, los objetivos de este proyecto son los siguientes: 1) Comparar empíricamente el modelo Poisson y modelo de Cox en la estimación de las medidas epidemiológicas de interés (riesgos relativos de IP y sus intervalos de confianza) mediante los datos de una cohorte de trabajadores afiliados al régimen general de la Seguridad Social. 2) Describir la incidencia de casos de IP entre 2004 y 2007 en una cohorte de 768.454 trabajadores afiliados al régimen general de la Seguridad Social, según sexo, edad, comunidad autónoma, nivel de estudios, tamaño de la empresa y actividad económica en España

M.M.O. Geocaching game with modular connections

Treballs Finals de Grau d'Enginyeria Informàtica, Facultat de Matemàtiques, Universitat de Barcelona, Any: 2015, Director: Eloi Puertas i PratsM.M.O. Geocaching Game with Modular Connections is a final grade project that pretends to create a game for Android devices, where the users participate in a massive multiplayer online experience in real time and located by GPS. This project wants to be close to the new devices, services offered by other companies, libraries,... to have an end product in the modern market, using concepts like geocaching to narrow the distance between users using a synchronized and online service

Comparación de la regresión Poisson y la regresión de Cox: aplicación al estudio de la incapacidad permanente en una cohorte de 768.454 trabajadores afiliados a la Seguridad Social

Este proyecto quiere cumplir dos objetivos: uno, de metodología estadística (objetivo 1) y el otro, de salud pública (objetivo 2). En concreto, los objetivos de este proyecto son los siguientes: 1) Comparar empíricamente el modelo Poisson y modelo de Cox en la estimación de las medidas epidemiológicas de interés (riesgos relativos de IP y sus intervalos de confianza) mediante los datos de una cohorte de trabajadores afiliados al régimen general de la Seguridad Social. 2) Describir la incidencia de casos de IP entre 2004 y 2007 en una cohorte de 768.454 trabajadores afiliados al régimen general de la Seguridad Social, según sexo, edad, comunidad autónoma, nivel de estudios, tamaño de la empresa y actividad económica en España

High-power test device for package thermal assessment and validation of thermal measuremetn tecniques

This paper describes the structure and thermal behavior of a high-power thermal test chip (up to 200 W/cm2) designed for power electronics package assessment, which has also been used for the validation of thermal measurement techniques. In particular, we show two application examples where the proposed device allowed the assessment of different power substrate technologies, and the validation of temperature measurement techniques used to characterize the high frequency behavior of circuits and devices in the frequency domain using the heterodyne technique.Postprint (published version

Hot spot analysis in integrated circuit substrates by laser mirage effect

3 páginas, 2 figuras.This work shows an analytical and experimental technique for characterizing radial heat flow present in integrated circuits (ICs) when power is dissipated by integrated devices. The analytical model comes from the resolution of the Fermat equation for the trajectory of rays and supposing a spherical heat source dissipating a time-periodic power. An application example is presented; hence demonstrating how hot spots and heat transfer phenomena in the IC substrate can be characterized. The developed method may become a practical alternative to usual off-chip techniques for inspecting hot spots in ICs and to experimentally characterize heat flow in the semiconductor substrate.This work has been partially supported by the Consejo Superior de Investigaciones Científicas (CSIC) (under contract “Junta para la Ampliación de Estudios,” JAEDoc No. E-08–2008–0637732) and the Spanish Ministry of Science and Innovation (research programs THERMOS TEC2008- 05577, RUE CSD2009-00046, TERASYSTEMS TEC2008- 01856, and Ramón y Cajal RYC-2010-07434).Peer reviewe

Analysis of solid state relay solutions based on different semiconductor technologies

This paper provides an analysis on the design, implementation and operation of Bi-Directional Switches (BDS) based on power semiconductor devices intended to replace Electro Mechanical Relays (EMR) in home appliances. Static and dynamic characterizations of test vehicles developed using different power device semiconductor technologies (TRIAC, Super Junction (SJ) MOSFET, IGBT...) are presented. At this time, emerging Gallium Nitride High Electron Mobility Transistors (GaN HEMTs) seem to be very suitable for the mentioned applications. Actually, GaN HEMTs based BDS has demonstrated to be the best solution to replace EMRs, with a high expectation to a significant cost reduction

Reduced-Order Thermal Behavioral Model Based on Diffusive Representation

14 páginas, 15 figuras, 2 tablas.-- et al.The virtual prototyping of power electronic converters requires electrothermal models with various abstraction levels and easy identification. Numerous methods for the construction of compact thermal models have been presented in this paper. Few of them propose state-space models, where the model order can be controlled according to the necessity of the virtual prototyping analyses. Moreover, the model reduction methods require the experience of the engineer and previous calibration. Diffusive representation (DR) is proposed here as an original and efficient method to build compact thermal models as state-space models. The model reduction is obtained through the model parameter identification and/or the time horizon of the measurement data provided for the identification. Instead of eigenvalue elimination, the method enables to specify adequately inside the model the frequency domain wished for the virtual analysis at hand. The proposed method is particularly dedicated to the system optimization phases. Experimental and simulation results are in good agreement. The advantages and limitations of the DR are discussed in comparison to published methods.Peer reviewe

A methodology to determine gaseous emissions in a composting plant

Environmental impacts associated to different waste treatments are of interest in the decision-making process at local, regional and international level. However, all the environmental burdens of an organic waste biological treatment are not always considered. Real data on gaseous emissions released from full-scale composting plants are difficult to obtain. These emissions are related to the composting technology and waste characteristics and therefore, an exhaustive sampling campaign is necessary to obtain representative and reliable data of a single plant. This work proposes a methodology to systematically determine gaseous emissions of a composting plant and presents the results obtained in the application of this methodology to a plant treating source-separated organic fraction of municipal solid waste (OFMSW) for the determination of ammonia and total volatile organic compounds (VOC). Emission factors from the biological treatment process obtained for ammonia and VOC were 3.9 kg Mg OFMSW⁻¹ and 0.206 kg Mg OFMSW⁻¹ respectively. Emissions associated to energy use and production were also quantified (60.5 kg CO₂ Mg OFMSW⁻¹ and 0.66 kg VOC Mg OFMSW⁻¹). Other relevant parameters such as energy and water consumption and amount of rejected waste were also determined. A new functional unit is presented to relate emission factors to the biodegradation efficiency of the composting process and consists in the reduction of the Respiration Index of the treated material. Using this new functional unit, the atmospheric emissions released from a composting plant are directly related to the plant specific efficiency

Output Power and Gain Monitoring in RF CMOS Class A Power Amplifiers by Thermal Imaging

© 2019 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes,creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.The viability of using off-chip single-shot imaging techniques for local thermal testing in integrated Radio Frequency (RF) power amplifiers (PA’s) is analyzed. With this approach, the frequency response of the output power and power gain of a Class A RF PA is measured, also deriving information about the intrinsic operation of its transistors. To carry out this case study, the PA is heterodynally driven, and its electrical behavior is down converted into a lower frequency thermal field acquirable with an InfraRed Lock-In Thermography (IR-LIT) system. After discussing the theory, the feasibility of the proposed approach is demonstrated and assessed with thermal sensors monolithically integrated in the PA. As crucial advantages to RF-testing, this local approach is noninvasive and demands less complex instrumentation than the mainstream commercially available solutions.Peer ReviewedPostprint (author's final draft