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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.
231

Kontrollsystem till Markberedare : Styrning till Invers-Markberedare

Ekman Svahn, Edvin Benjamin January 2020 (has links)
Syftet med detta examinationsarbete är att utveckla ett kontrollsystem för en inversmarkberedningsprototyp.En simuleringsmodell har skapats för att utveckla ett kontrollsystem med syftet att validera och verifiera prototypens effektivitet. Simuleringsuppställningen är skapad i Simulink, där en del av prototypen är importerad som en solidmodell vilken sammankopplas med en modell av ett hydraulsystem som styr solidmodellens rörelse. I Simuleringsmiljön utvecklades reglering samt styrlogik för prototypen. När regleringen var färdig att testas kontrollerades det att mjukvaran läsa av aktuella sensorer och att utsignaler från kontrollsystemet når hårdvaran, samt att den avsedda rörelsen utförs i verkligheten. Detta projekt har därmed resulterat i en simuleringsmodell, ett kontrollsystem, samt förutsättningar för att kunna verifiera resultaten i verkligheten. / This thesis treats the development of a control system for an inverse soil conditioner prototype. A simulation model was created to develop a control system with the purpose of validation and verification of the prototypes efficacy. The simulation model is created in Simulink, where a part of the soil conditioner is imported as a solid model, which then is coupled to a model of a hydraulic system. In the simulation a control system and regulator were implemented and tuned. when the software was test-ready the hardware-interface was tested to validate that the current software could receive inputs and send meaningful outputs, and then real movements were logged to validate the software function for the machine. The results of this project can then be summarized as a simulation model, a control system, and a solid basis for real world verification are completed.
232

System Modeling of Next Generation Digitally Modulated Automotive RADAR (DMR)

January 2019 (has links)
abstract: State-of-the-art automotive radars use multi-chip Frequency Modulated Continuous Wave (FMCW) radars to sense the environment around the car. FMCW radars are prone to interference as they operate over a narrow baseband bandwidth and use similar radio frequency (RF) chirps among them. Phase Modulated Continuous Wave radars (PMCW) are robust and insensitive to interference as they transmit signals over a wider bandwidth using spread spectrum technique. As more and more cars are equipped with FMCW radars illuminate the same environment, interference would soon become a serious issue. PMCW radars can be an effective solution to interference in the noisy FMCW radar environment. PMCW radars can be implemented in silicon as System-on-a-chip (SoC), suitable for Multiple-Input-Multiple-Output (MIMO) implementation and is highly programmable. PMCW radars do not require highly linear high frequency chirping oscillators thus reducing the size of the final solution. This thesis aims to present a behavior model for this promising Digitally modulated radar (DMR) transceiver in Simulink/Matlab. The goal of this work is to create a model for the electronic system level framework that simulates the entire system with non-idealities. This model includes a Top Down Design methodology to understand the requirements of the individual modules’ performance and thus derive the specifications for implementing the real chip. Back annotation of the actual electrical modules’ performance to the model closes the design process loop. Using Simulink’s toolboxes, a passband and equivalent baseband model of the system is built for the transceiver with non-idealities of the components built in along with signal processing routines in Matlab. This model provides a platform for system evaluation and simulation for various system scenarios and use-cases of sensing using the environment around a moving car. / Dissertation/Thesis / Masters Thesis Engineering 2019
233

Zielsystemunabhängiger Modellbasierter Entwurf auf der Basis von MATLAB/Simulink® mit einem vollständigen Model in the Loop-Test und automatischer Code-Generierung für einen Mischprozess

Büchau, Bernd, Gröbe, Gerald 27 January 2022 (has links)
Auf der Basis eines modellbasierten Entwurfs mit MATLAB/Simulink® wird der Entwurf für einen Mischprozess einer Mischstation vorgenommen. Durch den Einsatz der Toolbox PLC Coder™ von Mathworks® kann dieser Entwurf ohne jegliche Änderungen für aktuell 12 Automatisierungssysteme verschiedener Hersteller verwendet werden, so dass dies als ein zielsystemunabhängiger Entwurf angesehen werden kann. Der Vorteil besteht darin, dass nicht wie bisher ein klassischer Entwurf des Systems entsprechend IEC 61131 Teil 3 mit einer entsprechenden hersteller- bzw. systemspezifischen Entwicklungsumgebung durchgeführt wird, sondern ein hersteller- und systemunabhängiger Entwurf mit den zur Verfügung stehenden Werkzeugen von Simulink vorgenommen werden kann. Mit der verwendeten Toolbox PLC Coder™ für MATLAB/ Simulink® wird strukturierter Text nach IEC 61131 Teil 3 für das jeweilige Automatisierungssystem automatisch generiert. Im vorliegenden Fall wird als Automatisierungssystem eine SIMATIC ET 200SP Open Controller mit entsprechenden Erweiterungsmodulen (digitale und analoge Ein- und Ausgänge usw.) und das TIA Portal in der Version 15.1 der Fa. Siemens eingesetzt. / Für den Mischprozess, eine Mischstation, werden Flüssigkeiten aus drei verschiedenen Behältern in verschiedenen vorgegebenen Mischverhältnissen und Mengen dosiert und in einen Mischbehälter ge-leitet. Hierfür wird der modellbasierte Entwurf primär mittels endlicher Zustandsautomaten mit einer unterlagerten Durchflussmengenregelung in insgesamt neun Subsystemen vorgenommen. Um eine möglichst hohe Genauigkeit des Mischproduktes zu erzielen, wird hierbei die Dosierung der verschie-denen Flüssigkeiten volumengesteuert vorgenommen. Für den vollständigen modellbasierten Entwurf der Automatisierung der Mischstation, dessen Visua-lisierung sowie der Modellierung des HMI mittels Apps des App Designers von MATLAB/ Simulink® wird ein vollständiger Model in the Loop (MIL)-Test in Realzeit zur Verifikation des Gesamtsystems durchgeführt, der hier den Schwerpunkt darstellt. Durch den auf einem deutlich höheren Abstraktionsniveau durchgeführten modellbasierten Entwurf und den MIL-Test werden die Implementierungs- und Inbetriebnahmephase minimal. Abschließend werden die wesentlichen Vorteile des modellbasierten Entwurfs behandelt und ein Aus-blick gegeben.
234

Analysis of the efficiency and performance of half-cell solar modules

Hernandez, Diego January 2023 (has links)
Solar photovoltaic energy has gained great importance in the last couple of years, as its costs getlower and the total installed capacity increases. As a result of this, new technologies are arisingwithin the field, with the objective of increasing performance and reducing costs. One of themis the half-cell solar modules which, among other advantages, are said to perform better undershaded conditions compared to standard modules.This project checks the veracity of this statement. For that, a Matlab/Simulink model capable ofrepresenting the behavior of the JAM60S21-365-MR solar module has been created, andexperimentally calibrated with measurements performed in an actual panel. After the modelaccuracy has been checked, it has been used to simulate various shaded scenarios for standardand half-cell modules, to carry out an equivalent comparison between the two.The results for the model show a maximum error of 0.62% for the reference case, and of 6.06%for the worst 4-module-string simulation. This has been found to be an acceptable error, whichis created mainly as a result of temperature measuring inaccuracies and the rough estimation ofsolar cell model parameters. To reduce it, it is recommended that these issues are addressed.Which module does better under shading has been found to be dependent on multiple factors:The temperature and irradiance at which the module operates, its constructive parameters, thenumber of series or parallel connected devices and the shape and size of the shadow. This lastone is the one with the biggest impact in electrical power output. Because of it, the most usualcases for shadowing in PV facilities have been compared. For equivalent modules, shading in thedirection of the string of a single cell is less detrimental in half-cell modules; however, if thatshadow covers a whole row, it is equally damaging. If a full cell is 50% shaded in this scenario, a20% less power is lost in the half cell module compared to the normal one. On the other hand,shadowing in the direction on the bypass-diode line tends to slightly benefit standard modulesfor equal cell parameters if the shadowed full-cell percentage is below 50%, for both cell androw shading. However, as this value increases, half-cell modules tend to gain an advantage overstandard ones.
235

Stability of a Fuzzy Logic Based Piecewise Linear Hybrid System

Seyfried, Aaron W. 01 June 2013 (has links)
No description available.
236

REAL TIME SIMULATION AND HARDWARE-IN-LOOP TESTING OF A HYBRID ELECTRIC VEHICLE CONTROL SYSTEM

Medisetti, Praveen 08 August 2007 (has links)
No description available.
237

Unmanned Aerial Vehicle Powered by Hybrid Propulsion System / Drönare driven på vätgas-batterihybridsystem

Åkesson, Elsa, Kempe, Maximilian, Nordlander, Oskar, Sandén, Rosa January 2020 (has links)
I samband med den globala uppvärmningen ökar efterfrågan för rena och förnybara bränslen alltmer i dagens samhälle. Eftersom flygindustrin idag är ansvarig för samma mängd växthusgaser som all motortrafik i Sverige, skulle ett byte till en avgasfri energikälla för flygfarkoster vara ett stort framsteg. Därför har projektet genom modellering framtagit ett hybridsystem av ett batteri och en bränslecell och undersökt hur kombinationen av olika storlekar på dem presterar i en driftcykel. Då batterier har hög specifik effekt men är tunga, kompletteras de med fördel av bränsleceller, som är lättviktiga och bidrar med uthållig strömförsörjning. På så sätt blir hybriden optimal för flygfarkoster. Kandidatarbetet är en del av projektet Green Raven, ett tvärvetenskapligt samarbete mellan instutitionerna Tillämpad Elektrokemi, Mekatronik och Teknisk Mekanik på Kungliga Tekniska Högskolan. Driftcykelmodelleringen gjordes i Simulink, och flera antaganden gjordes beträffande effektprofilen, samt bränslecellens mätvärden och effekt. Tre olika energihushållningsscheman skapades, vilka bestämde bränslecellseffekten beroende på vätgasnivån och batteriets laddningstillstånd. Skillnaden på systemen var vilka intervall av laddningstillstånd hos batteriet som genererade olika effekt hos bränslecellen.  Det bästa alternativet visade sig vara 0/100-systemet, eftersom det var det enda som inte orsakede någon degradering av bränslecellens kapacitet. / In today’s society, with several environmental challenges such as global warming, the demand for cleanand renewable fuels is ever increasing. Since the aviation industry in Sweden is responsible for the sameamount of greenhouse gas emissions as the motor traffic, a change to a non-polluting energy source forflying vehicles would be considerable progress. Therefore, this project has designed a hybrid system of abattery and a fuel cell and investigated how different combinations of battery and fuel cell sizes perform ina drive cycle, through computer modelling. As batteries possess a high specific power but are heavy, thefuel cells with high specific energy complement them with a sustained and lightweight power supply,which makes the hybrid perfect for aviation. The bachelor thesis is a part of Project Green Raven, aninterdisciplinary collaboration with the institutions of Applied Electrochemistry, Mechatronics andEngineering Mechanics at KTH Royal Institute of Techology. The drive cycle simulations were done inSimulink, and several assumptions regarding the power profile, fuel cell measurements and power weremade. Three different energy management strategies were set up, determining the fuel cell powerdepending on hydrogen availability and state of charge of the battery. The strategies were called 35/65,20/80 and 0/100, and the difference between them was at which state of charge intervals the fuel cellchanged its power output. The best strategy proved to be 0/100, since it was the only option which causedno degradation of the fuel cell whatsoever.
238

Controller Modeling and Stability Analysis of Multiple Input Single Output DC-DC Converter

Adhikari, Astha 01 March 2021 (has links) (PDF)
This thesis entails the stability analysis of the Multiple Input Single Output (MISO) DC-DC converter developed for the DC House Project at Cal Poly. A frequency domain control system model of the MISO converter was designed and constructed using MATLAB Simulink. Transfer functions were derived and modeled for each stage of the converter to best fit the converter circuit system used in the original MISO circuit. Stability metrics such as overshoot, undershoot, rise time, phase margin and gain margin were measured to evaluate and analyze the stability of the converter. These metrics were measured with the original model including the current sharing network that allows load sharing between multiple MISO modules. The simulation results demonstrate that based on the existing model, the system is stable with a gain margin of infinity and phase margin of around 40 degrees at crossover frequency of 47kHz with nominal input voltage of 24V. Another compensator was proposed to overcome the shortcomings of the original compensator model with respect to the overshoot and phase margin. The new compensator model improved the phase margin at the same crossover frequency with a higher rise time and lowered percent overshoot. Additional improvements and tradeoffs are further discussed to help with the decision when designing a compensator for DC-DC converter that uses the current mode control technique.
239

Dynamics Simulation and Optimal Control of a Multiple-Input and Multiple-Output Balancing Cube

Haimerl, Felix K 01 June 2018 (has links) (PDF)
This thesis document outlines the development of a multibody dynamics simulation of an actively stabilized multiple-input, multiple-output, coupled, balancing cube and the process of verifying the results by implementing the control algorithm in hardware. A non-linear simulation of the system was created in Simscape and used to develop a Linear Quadratic Gaussian control algorithm. To implement this algorithm in actual hardware, the system was first designed, manufactured, and assembled. The structure of the cube and the reaction wheels were milled from aluminum. DC brushless motors were installed into the mechanical system. In terms of electronics, a processor, orientation sensor, motor drivers, analog to digital converters, and a pulse width modulation board were assembled into the cube. Upon completion, the software to control the cube was developed using Simulink and run on a Raspberry Pi computer within the mechanism.
240

Гидропривод наклона дуговой сталеплавильной печи ДСП-100 : магистерская диссертация / Hydraulic tilt drive of the arc steelmaking furnace DSP-100

Славницкий, Р. А., Slavnitskiy, R. A. January 2022 (has links)
В работе с использованием среды Matlab и пакетами расширений Simulink и Fluids выполнен динамический анализ имитационной модели гидропривода наклона дуговой сталеплавильной печи. Актуальность темы выпускной квалификационной работы обусловлена экономией времени и ресурсов предприятия при создании имитационной модели вместо стендовой модели механизма «в железе», а также наглядностью полученной модели. Динамический анализ механизма выполнен путем создания блок-схемы гидравлического привода с рассчитанными для заданной системы параметрами, выполненной в расширении Fluids и подачи сигнала усилия на твердотельную модель печи, выполненной в расширении Simulink. / This article contains dynamic analysis of the simulation model of the hydraulic tilt drive of an arc steelmaking furnace was performed with use of the Matlab environment and Simulink and Fluids extension packages. The relevance of the topic of the final qualifying work is due to the saving of time and resources of the enterprise when creating a simulation model instead of a bench model of the mechanism "in metal", as well as the visibility of the resulting model. The dynamic analysis of the mechanism was performed by creating a block diagram of a hydraulic drive with parameters calculated for a given system, performed in the Fluids expansion and sending a force signal to a solid-state furnace model performed in the Simulink expansion.

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