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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
331

Laserový vibrometr s 2D rozmítáním / Laser vibrometer with 2D scanning system

Rajm, Martin January 2012 (has links)
This thesis deals in the theoretical part with the non-contact vibration measurement by single point Laser Doppler vibrometer and it concretes constructions used in practice. It deals also with the possibilities of the laser beam scanning to measure the vibrations in the plane and there are also listed suitable-commercial systems for this solution. Mentioned sweep is immediately necessary for 2D scanning vibrometer construction. In the practical part, the single-point laser vibrometer OFV-5000 was expanded by scanning galvo system, supplemented by a measuring cards for signal acquisition from the vibrometer and suitable control hardware was chosen for mentioned laser. For the resulting hardware assembly was designed and implemented in LabVIEW measurement software, to control the 2D scanning system, to set the position of the laser beam and to process and to visualize of measured vibration signals in the plane. The functionality of the developed measuring system was checked by performed measurement and visualization of the velocity vibration of restraint girder, excited by shaker.
332

Implementace algoritmů řízení elektrických motorů v systémech CompactRIO / Implementation of Electric Motor Control Algoritms in CompactRIO systems

Gléba, Gergely January 2013 (has links)
This master’s thesis deals with the implementation of existing algorithms of electric AC motor control in Matlab Simulink to LabVIEW Control Design and Simulation. The first part of the thesis treats with the deduction of a mathematical model of an asynchronous motor, permanent magnet synchronous motor and with the theory of vector control of AC motors. In the next part there is a brief guide to create simulation algorithms in LabVIEW environment and to create the model of a motor with EMI functions in language C. The last part contains the comparison of Matlab Simulink and LabVIEW simulation tools.
333

Uživatelské měřicí moduly pro platformu cRIO / User-defined Measurement Modules for cRIO

Pivnička, Martin January 2015 (has links)
This thesis describes design and manufacture of measuring and communication modules for CompactRIO platform. In the first section is described platform from National Instrument suitable for measurement and control technology. There is written more fact about CompactRIO. The second part is focused on description of the hardware requirements needed to construct the module, communication and working modes. The third part describes information about support programs. At the end of third part is describes practical application of input digital card. Next section consists of practical proposal modules (input / output analog module, GPS modulu) and achievements.
334

Příprava grafenu metodou CVD / The preparation of Grafen by method CVD

Procházka, Pavel January 2012 (has links)
This diploma thesis is mainly focused on the fabrication of graphene layers on the copper foil by the Chemical Vapor Deposition (CVD). For this purpose the high-temperature chamber for the production of the graphene was completed and fully automated. The production of the high area graphene on the copper foil was experimentally achieved. The Raman microscopy and X-ray photoelectron spectroscopy measurements proved that the produced graphene is mostly a monolayer. Graphene layer was transferred on non-conductive substrate.
335

Měřicí a regulační systém vzduchového zemního výměníku tepla / Measurement and control system of an air-ground heat exchanger

Bielik, Jan January 2015 (has links)
Diploma thesis deals with design of measurement and control system of an air-ground heat exchanger, which is placed in area of FME BUT in Brno. System is built in development environment LabVIEW and it is using modules CompactDAQ from National Instrument. Developed system managed trial operation, during which was designed additional changes of measurement equipment for determine another magnitudes, which help us with future evaluation of benefit of air-ground heating exchanger. It was designed some operational modes, which solve different ways of control air-ground heat exchanger.
336

Implementace metod pro měření rychlosti otáčení rotačních strojů na platformě cRIO / Implementation of methods for measurement of rotational speed using cRIO platform

Fábry, Tomáš January 2016 (has links)
This diploma thesis implements methods for a measurement of rotational speed. It is implemented on the Compact RIO platform from National Instruments. Corresponding SW is implemented using the graphical programming language G in LabView environment. Developed system uses two different sensors – incremental encoder and tacho sensor for measurements of rotational speed. Thesis further analysis and implements a method for an encoder nonlinearity determination and for its on-line correction. For used methods, effects adding errors into the measurements are evaluated and quantified.
337

Laserový 2D skener / 2D laser scanner

Tomek, Tomáš January 2016 (has links)
This thesis deals with design and implementation of extension module that enables 2D scanning with single-point interferometer. Afterwards is here solved question of software, which output data can be visualized in ModalVIEW by ABSignal company. My work also contains an overview of LDV sensors and scan systems, which are used to laser beam steering.
338

Erweitern eines Gentoo-Linux mit RTAI, LabVIEW und Comedi als digitaler Regler

Jäger, Markus 12 February 2018 (has links)
Der Einsatz von Computern, zur unterstützenden Durchführung physikalischer Experimente, gewinnt immer mehr an Bedeutung. Computer, unter anderem auch Personal Computer (kurz PC), können durch ihre heutige Leistungsfähigkeit, immer mehr nützliche Funktionen während eines physikalischen Experimentes übernehmen. Diese Arbeit beschäftigt sich mit dem Vorbereiten eines solchen PC, welcher für die Umsetzung einer Regelschaltung für ein physikalisches Experiment genutzt werden kann. Dazu werden Gentoo-Linux, RTAI, Scilab/Scicos und Comedi verwendet. Besonderer Schwerpunkt der Arbeit ist dabei die Regelung in Echtzeit auszuführen. Im Verlauf der Arbeit werden Hardware- sowie Software-Ansprüche und deren Anpassungen besprochen, so dass alle Voraussetzungen des Experiment-PC, zur Umsetzung eines zuverlässigen Regelprozesses, erfüllt werden. Aus Gründen, welche in dieser Arbeit erläutert werden, wurde der Experiment-PC mit der Open-Source Linux-Distribution namens Gentoo ausgestattet. Zusätzlich verfügt der Experiment-PC über eine Mess- und Steuerkarte, welche es dem Experiment-PC erlaubt Signale aus dem Experiment aufzunehmen und eine entsprechende Regelung, durch die Ausgabe von Signalen, vorzunehmen.
339

Feeder Dynamic Rating Application for Active Distribution Networks using Synchrophasors

Singh, Narender January 2016 (has links)
There is an ever increasing demand of electricity and to meet this demand, installation of new transmission and distribution lines is required. This task requires a significant investment and consent from the respective authorities. An alternative is to utilize maximum capability of the existing lines. Static line ratings are based on a conservative estimate, which means that on most occasions, the actual capacity of lines is much higher than the static line ratings. In order to provide a solution to this problem, this thesis introduces an approach that has been developed to utilize real time weather conditions, conductor sag data and the actual line loading of the conductor from PMU to provide dynamic line ratings for active distribution networks. The application has been developed in LabVIEW environment which provides a user friendly front panel where real-time ampacity can be seen as a waveform while being compared to the actual line loading.  The developed application has been tested on the reference grid created for IDE4L project. The ampacity calculation method introduced here makes use of real-time data available through a real-time simulator in SmarTS lab at KTH, Sweden. / Det är ett ökande behov av elektricitet och för att möta detta behövet, installation av nya transmission och distributionsledningar behövs. Denna utbyggnad kräver ett stort engagemang och förståelse från ansvariga grupper. Ett alternativ är att utnyttja max-kapaciteten på redan befintliga ledningar. Installerade ledningar har räknats på ett konservativt sätt, vilket innebär att det vid vissa tillfällen går att öka belastingen på på dessa. För att ge en lösning på detta problem, introducerar den här avhandlingen en metod för att använda realtids-väderdata, tabeller för ledningarnas utvidgning och realtids-belastningsdata från PMU för att framställa dynamisk data för aktiva distributions-nätverk. Applikationen har utvecklas i LabVIEW-miljön som har ett användarvänligt GUI, där “Real-time ampacity” kan ses som en vågform medans den jämförs mot den faktiska belastningen på ledningen.  Den utvecklade appliktionen har testats på referens-miljön som skapts för IDE4L projektet. “Ampacity calculation metoden” som introduceras här använder sig av realtidsdata som görs tillgänglig igenom en realtids-simulator i SmarTSlab på Kungliga Tekniska Högskolan i Sverige.
340

An Investigation of the Ward Leonard System for Use in a Hybrid or Electric Passenger Vehicle

Telford, Cody L. 18 April 2012 (has links) (PDF)
Since the early 1900's demand for fuel efficient vehicles has motivated the development of electric and hybrid electric vehicles. Unfortunately, some components used in these vehicles are expensive and complex. Today's consumer electric vehicles use dangerously high voltage,expensive electronic controllers, complex battery management systems and AC motors. The goal of this research at BYU is to increase safety by lowering the operating voltage and decrease cost by eliminating expensive controllers and decrease the number of battery cells. This paper specifically examines the use of a Ward Leonard Motor Control system for use in a passenger vehicle. The theory of the Ward Leonard system as an Infinitely Variable Transmission (IVT) is presented along with its history and past uses. Analogous systems are presented and similarities made in an attempt to enlighten designers to a broader design approach to increase safety and decrease cost of an electric or hybrid electric vehicle. The results of this research include a characterization of the Ward Leonard system as an IVT for use in an electric or hybrid (EV or HEV) passenger vehicle. These results include a study of past uses of the Ward Leonard system and what method is now used as a replacement. The theory of the Ward Leonard system and it operation is explained to an extent that someone not familiar with electronics can understand its working principles. A Control Factor metric was developed as a result of this research to measure the Ward Leonard System's ability to reduce the size of the electronic controller for application in an EV or HEV. The potential cost reduction of the electronic controller that would be used to control the Ward Leonard System compared with current EV and HEV vehicles was also research and identified. A bench top model of the Ward Leonard system was tested validating the Control Factor metric. The Ward Leonard system is capable of reducing the controller size by 77% and potentially reducing its cost by 68% or more. This work also provides performance characteristics for automotive designers and offers several design alternatives for EV and HEV architectures allowing the reduction of high voltage, the use of AC inverters, AC motors, expensive controllers and high cell count battery packs.

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