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Contribución al desarrollo de sensores de temperatura y redes de sensores en tecnología de fibra ópticaMadruga Saavedra, Francisco Javier 06 October 2006 (has links)
Este trabajo de tesis recoge las contribuciones aportadas en el campo de los sensores de fibra óptica en tres ámbitos de trabajo. Un sistema sensor de alta temperatura sin contacto con transductores de fibras ópticas de sílice se ha presentado. Dos topologías de "ojo abierto" y "ojo cerrado" y un algoritmo de decodificación "pirometría de banda dual" propuesto en este trabajo son las novedosas aportaciones presentadas. El sistema ha sido validado en laboratorio y en pruebas de campo de forma exitosa. Para sensores de temperatura con fibras dopadas con Erbio se ha demostrado que su máxima sensibilidad tiene lugar cuando la longitud utilizada es superior a la óptima exigida por el bombeo. Finalmente se ha modelado y validado en laboratorio una red de sensores acústicos basados en interferómetros Fabry-Perot de cavidad larga determinando a partir del modelo obtenido la fase mínima detectable y la visibilidad máxima del sistema. / The thesis collects contributions in the field of optic fibre sensors for three areas. A high temperature sensor system without contact based on silica optic fibre transducers has been submitted. Two topologies "open eye" and "closed eye" and a dual band pyrometer decoding algorithm are the submitted innovative contributions. The system has been validated successful in the laboratory and field tests so. Another contribution has been the demonstration that the maximum sensitivity for temperature sensors based on Er-doped fibres occurs when the used length is more than the optimum required by pumping. Finally a network of acoustic sensors based on Fabry-Perot fibre interferometers has been modelled and validated in the laboratory. The minimum detectable phase and maximum visibility of the system has been obtained from the proposed and validated model
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Temperaturbestimmung an IGBTs und Dioden unter hohen Stoßstrombelastungen / Temperature measurement of IGBTs and Diodes under high surge current loadsSimon, Tom 03 June 2015 (has links) (PDF)
Diese Arbeit beschäftigt sich mit drei verschiedenen Temperaturmessmethoden VCE, VGTH sowie über die Messung der thermsichen Impedanz mit 10ms langen Lastimpulsen und vergleicht die Messergebnisse mit zwei Simulatoren. Dabei wird ein Schaltungs- sowie ein Halbleitersimulator verwendet und das bisherige Simulationsmodell angepasst.
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Quantitative measurements of temperature using laser-induced thermal grating spectroscopy in reacting and non-reacting flowsLowe, Steven January 2018 (has links)
This thesis is concerned with the development and application of laser induced thermal grating spectroscopy (LITGS) as a tool for thermometry in reacting and non-reacting flows. LITGS signals, which require resonant excitation of an absorbing species in the measurement region to produce a thermal grating, are acquired for systematic measurements of temperature in high pressure flames using OH and NO as target absorbing species in the burned gas. The signal obtained in LITGS measurements appears in the form of a time-based signal with a characteristic frequency proportional to the value or the sound speed of the local medium. With knowledge of the gas composition, the temperature can be derived from the speed of sound measurement. LITGS thermometry using resonant excitation of OH in the burned gas region of in oxygen enriched CH4/O2/N2 and CH4/air laminar flames was performed at elevated pressure (0.5 MPa) for a range of conditions. Measurements were acquired in oxygen enriched flames to provide an environment in which to demonstrate LITGS thermometry under high temperature conditions (up to 2900 K). The primary parameters that influence the quality of LITGS signal were also investigated. The signal contrast, which acts as a marker for the strength of the frequency oscillations, is shown to increase with an increase in the burnt gas density at the measurement point. LITGS employing resonant excitation of NO is also demonstrated for quantitative measurements of temperature in three environments – a static pressure cell at ambient temperature, a non-reacting heated jet at ambient pressure and a laminar premixed CH4/NH3/air flame operating at 0.5 MPa. Flame temperature measurements were acquired at various locations in the burned gas close to a water-cooled stagnation plate, demonstrating the capability of NO-LITGS thermometry for measuring the spatial distribution of temperature in combustion environments. In addition, the parameters that in influence the local temperature rise due to LITGS were also investigated in continuous vapour flows of acetone/air and toluene/air mixtures at atmospheric conditions. Acetone and toluene are commonly targeted species in previous LITGS measurements due to their favourable absorption characteristics. Results indicate that LITGS has the potential to produce accurate and precise measurements of temperature in non-reacting flows, but that the product of the pump intensity at the probe volume and the absorber concentration must remain relatively low to avoid significant localised heating of the measurement region.
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Komunikační zařízení přes GSM/GPRS / Communication devices over GSM/GPRSPrečan, David January 2010 (has links)
This master thesis deals with a data remote transmission by means of SMS and GPRS technology. The overview of current solutions is presented and then a remote temperature measurement and a data transmission employing a communication module GSM/GPRS TM1 through GSM network using GPRS technology is described. As a response to an impulse, the communication module sends SMS. The technical solution is described in details including HW and SW design of the data transfer and processing equipment using a ATmega 162 microprocessor. This equipment communicates with a server (PC), which displays the measured temperature. A prototype which was used for a validation of the design is also described.
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Řízení klimatických vlastností pěstebního boxu / Control system for greenhouseHaring, Filip January 2016 (has links)
This project deals with design and implementation of control system, which is used for regulation climate conditions in special grow box. Measured values are displayed on graphic LCD, sent to application in PC or displayed on web server. The project solves software and hardware implementation of measurement system.
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Temperaturbestimmung an IGBTs und Dioden unter hohen StoßstrombelastungenSimon, Tom 16 April 2015 (has links)
Diese Arbeit beschäftigt sich mit drei verschiedenen Temperaturmessmethoden VCE, VGTH sowie über die Messung der thermsichen Impedanz mit 10ms langen Lastimpulsen und vergleicht die Messergebnisse mit zwei Simulatoren. Dabei wird ein Schaltungs- sowie ein Halbleitersimulator verwendet und das bisherige Simulationsmodell angepasst.:Aufgabenstellung
Inhaltsverzeichnis
Nomenklatur
Einleitung
1. Grundlagen
1.1. Halbleitermaterialien
1.2. Dioden Grundlagen
1.2.1. pn-Übergang
1.2.2. Temperaturabhängigkeit der Diffusionsspannung des pn-Übergangs
1.2.3. Diodenstrukturen
1.3. IGBT Grundlagen
1.3.1. Funktionsweise und ESB
1.3.2. Statisches Verhalten des IGBTs
1.4. Messtechnische Bestimmung der virtuellen Sperrschichttemperatur
1.4.1. VCE(T)- und VGth(T)-Methode
1.4.2. Temperaturreferenzmessung – Kalibrierkennlinie
1.4.3. Wurzel(t)-Methode
1.5. Simulation der virtuellen Sperrschichttemperatur mittels thermischer Ersatzschaltbilder
1.5.1. Thermische Kenngrößen Rth, Cth
1.5.2. Transiente thermische Impedanz Zth
1.5.3. Ersatzschaltbild – Cauer-Netzwerk
1.6. Simulation der virtuellen Sperrschichttemperatur mittels Halbleitersimulator
1.7. Stoßstromereignisse
2. Vormessungen
2.1. Prüflinge
2.2. Messung der Sperrfähigkeit
2.2.1. Testaufbau – Schaltung
2.2.2. Testergebnisse
2.3. Messung des Ausgangskennlinienfeldes/ Durchlassmessungen
2.3.1. Testaufbau – Schaltung
2.3.2. Testergebnisse
2.4. Messung der Transferkennlinie
2.4.1. Testaufbau – Schaltung
2.4.2. Testergebnisse
2.4.3. Bestimmung des “pinch-off”-Bereiches
2.5. Aufnahme der Kalibrierkennlinien
2.5.1. Testaufbau – Schaltung
2.5.2. Testergebnisse
3. Temperaturbestimmung mittels thermischer Impedanz Zth
3.1. Testaufbau – Schaltung
3.2. Testergebnisse
4. Temperaturbestimmung am Stoßstrommessplatz
4.1. Ermittlung der Halbleitertemperatur nach einem Stoßstromereignis
4.1.1. Anpassung des Stoßstrommessplatzes
4.1.2. Pulsmuster VCE(T)-, VGth(T)-Messung
4.1.3. Testergebnisse
4.2. Ermittlung des Halbleitertemperaturverlaufes während des Stoßstromereignisses
4.2.1. Testaufbau - Schaltung
4.2.2. Pulsmuster VCE(T)-, VGth(T)-Messung
4.2.3. Testergebnisse
5. Simulation der Temperaturverläufe
5.1. Temperatursimulation mittels Halbleitersimulator
5.2. Temperatursimulation mittels Cauer-Netzwerk
5.3. Angepasste Temperatursimulation mittels Cauer-Netzwerk
6. Zusammenfassung und Ausblick
Anhang
Literaturverzeichnis
Selbstständigkeitserklärung
Danksagung
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Soustava hodnocení tepelného stavu prostředí a analýza jejich nejistot měření / Evaluation System of Thermal Condition Environment and his Measurement Uncertainties AnalyzeKošíková, Jana January 2013 (has links)
The Ph.D. thesis deals with the evaluation of indoor thermal environment in which people are located. A great attention is paid to the thermal comfort. If a person in a given environment does not feel well, then makes mistakes. Thermal comfort is created many parameters that can be monitored and managed. These parameters include not only temperature but also other parameters such as the mean radiant temperature, operative temperature, humidity and air velocity and the draft. All these parameters can be measured. The standard ČSN EN ISO 7726 is written how and what the parameters are measured. Furthermore, this standard provides requirements for measuring equipment. There are many professional measuring devices. Unfortunately, these devices are very expensive. Therefore are within the project GACR 101/09/H050 - Research on energy- saving equipment to achieve the quality of the indoor environment at our faculty developed sensors for thermal comfort, which have showed comparable accuracy measurements as a professional , but it will be cheaper than professional. Knowledge of real parameters of the developed sensor thermal comfort environment is important, as with any other measurement devices, and also need to verified whether it has the required accuracy. In order to objectively sensors testing were developed two chambers - the testing and calibration chamber. The developed sensors were tested both in the open laboratory, and also in the test chamber. Then uncertainties measurement were calculated from the results of measurements This work deals with the evaluation of thermal comfort, the measurement of parameters of thermal environment, the evaluating the results of measurements and determining the measurement uncertainty of the sensors. In this thesis, based on these results, were recommended suitable sensors for measuring various parameters environment.
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Bestimmung lebensdauerrelevanter Parameter von IGBTs im Antriebsumrichter von ElektrofahrzeugenHiller, Sebastian 21 December 2022 (has links)
Die Arbeit beschreibt verschiedene technische Ansätze zur Bestimmung der Alterung der Chip-Substrat-Verbindung. Eine der Schlüsseltechnologien ist hierbei die Bestimmung der virtuellen Sperrschichttemperatur. Es werden in der Arbeit verschiedene Möglichkeiten zur Bestimmung der virtuellen Chiptemperatur von IGBTs und der Alterung der Chip-Substrat-Verbindung vorgestellt und mit ihren Vor- und Nachteilen in der Umsetzbarkeit und in der Anwendbarkeit im Umrichter diskutiert.
Besondere Betrachtung findet dabei unter anderem die technische Umsetzung einer Messmethode, die auf einer kurzzeitigen Belastung im aktiven Bereich mit anschließender Bestimmung des Abkühlverhaltens basiert. Über einen Vergleich mit dem ursprünglichen Abkühlverhalten ist es mit den vorgestellten Verfahren gut möglich, die Chipalterung zu detektieren.
Weiterhin wird ein Verfahren vorgestellt, das die Bestimmung der virtuellen Chiptemperatur im Umrichter über eine Ermittlung der Millerplateauhöhe im Abschaltmoment des IGBTs ermöglicht.:1 Einleitung
2 Alterung von Leistungshalbleitern
3 Stand der Technik der Chiptemperaturbestimmung in der Umrichterschaltung
4 Untersuchungen temperaturabhängiger elektrischer Bauelementparameter
5 Wichtige Verfahren zur Bestimmung der Chiptemperatur in der Umrichterschaltung
6 Untersuchung eines Verfahrens zur Bestimmung der Chiptemperatur in der Umrichterschaltung mittels Millerplateauhöhe
7 Technische Umsetzbarkeit der gezeigten Messverfahren
8 Zusammenfassung und Ausblick
A Anhang / This work describes different technical approaches to determine the aging of the chip-substrate interconnection. One of the key technologies here is the determination of the virtual junction temperature. Various possibilities for determining the virtual chip temperature of IGBTs and the aging of the chip-substrate interconnection are presented in the work and discussed with their advantages and disadvantages in terms of feasibility and applicability in the converter.
Special consideration is given to the technical implementation of a measurement method based on a short-term load in the active area with subsequent determination of the cooling behavior. By comparing this with the original cooling behavior, it is possible to detect chip aging with the methods presented.
Furthermore, a method is presented that enables the determination of the virtual chip temperature in the inverter via a determination of the Miller plateau height at the switch-off moment of the IGBT.:1 Einleitung
2 Alterung von Leistungshalbleitern
3 Stand der Technik der Chiptemperaturbestimmung in der Umrichterschaltung
4 Untersuchungen temperaturabhängiger elektrischer Bauelementparameter
5 Wichtige Verfahren zur Bestimmung der Chiptemperatur in der Umrichterschaltung
6 Untersuchung eines Verfahrens zur Bestimmung der Chiptemperatur in der Umrichterschaltung mittels Millerplateauhöhe
7 Technische Umsetzbarkeit der gezeigten Messverfahren
8 Zusammenfassung und Ausblick
A Anhang
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Active dielectrophoretic trapping for deterministic single-cell encapsulation in droplet microfluidicsSurana, Prasanna January 2023 (has links)
The research work focuses on optimizing various parameters for controlling cells using negative dielectrophoresis and entrapping them in droplet microfluidics. This is achieved by developing a conductivity medium, combining CytoRecovery, BSA, and EDTA, to maintain a steady count of single cells with good viability over an extended period. The study involves the optimization of frequency and voltage applied to the electrodes to achieve the desired dielectrophoretic forces for long-term cell manipulation. The optimization is based on simulations performed using myDEP and COMSOL software. Additionally, the stability of the conductivity medium is tested during prolonged electric field applications. Considering the significance of working with cells, ensuring the temperature inside the channels remains within physiological limits is vital. Both COMSOL simulations and physical experiments using Rhodamine B dye are conducted to achieve this objective. Moreover, a well-designed process flow is proposed for performing cellular entrapment in droplets. Finally, a novel microfluidic cleaning protocol has been developed to efficiently eliminate both non-biological and biological contaminants from the microfluidic chamber. This innovative protocol has the potential to enable the reuse of any microfluidic chip that does not possess a functionalized surface. / Forskningsarbetet fokuserar på att optimera olika parametrar för att kontrollera celler med hjälp av negativ dielektrofores och fånga in dem i droppmikrofluidik. Detta uppnås genom att utveckla ett konduktivitetsmedium, som kombinerar CytoRecovery, BSA och EDTA, för att upprätthålla ett jämnt antal enstaka celler med god livsduglighet under en längre period. Studien involverar optimering av frekvens och spänning som appliceras på elektroderna för att uppnå de önskade dielektroforetiska krafterna för långvarig cellmanipulation. Optimeringen är baserad på simuleringar utförda med mjukvaran myDEP och COMSOL. Dessutom testas konduktivitetsmediets stabilitet under långvariga elektriska fälttillämpningar. Med tanke på betydelsen av att arbeta med celler är det viktigt att se till att temperaturen inuti kanalerna håller sig inom fysiologiska gränser. Både COMSOL-simuleringar och fysiska experiment med Rhodamine B-färgämne genomförs för att uppnå detta mål. Dessutom föreslås ett väldesignat processflöde för att utföra cellulär infångning i droppar. Slutligen har ett nytt mikrofluidrengöringsprotokoll utvecklats för att effektivt eliminera både icke-biologiska och biologiska föroreningar från mikrofluidkammaren. Detta innovativa protokoll har potential att möjliggöra återanvändning av alla mikrofluidiska chip som inte har en funktionaliserad yta.
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Měřící systém pro sledování efektivity fotovoltaického panelu / Measuring system of photovoltaic panels efficiencyHofman, Jiří January 2010 (has links)
This diploma thesis is focused on development and initial run of a measurement system whose aim is to measure photovoltaic panel efficiency. Experimental photovoltaic panel is installed outside the laboratory. Measurement system consists of the solar radiation measurement module (pyranometer), photovoltaic panel load module (panel power measurement) and panel climate measurement module. Data from measurement module is being captured via control computer for subsequent analysis of panel efficiency and climatic impacts on it.
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