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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.
1

Real time modeling, simulation and validation of protective relays

Saran, Ankush 11 December 2009 (has links)
The protection system plays an important role in the power system to detect the fault, isolate the faulted zone from the unaulted zone and restore the power supply to the healthy part. In order to validate the developed protection system, hardware in the loop (HIL) tests have been performed on several power system test cases using commercial overcurrent and distance relays from two vendors and a Real Time Digital Simulator (RTDS). Two-bus and eight-bus terrestrial power systems (TPS) as well as a 4-bus shipboard power system (SPS) are developed in RSCAD and used as power system test cases. The simulation results of the HIL tests provides the background to design the software overcurrent relay model, which should have the same functionality as that of the hardware commercial overcurrent relay. The test case power system with the developed software overcurrent relay model is simulated on RTDS for the same fault conditions in the software in the loop (SIL) test. The comparison of the HIL and SIL simulation results was used to validate the software overcurrent relay model. This research work is further extended to implement more complex operations like multiple relay operation and relay coordination using the developed overcurrent relay model. The first step is to conduct the multiple relay operation and relay coordination tests on the SPS and TPS using multiple commercial hardware overcurrent relays. The second step is to modify the RSCAD software overcurrent relay model by adding more functionality to produce the matching results as obtained in the first step for the same test cases under similar fault scenarios. In addition to modeling overcurrent relay, a differential relay was also modeled using LabVIEW. The relay model was tested for different types of fault conditions.
2

Application of a New Software Tool for the Automated Test of Automotive Electronic Control Unit Software

Amlinger, Hanna January 2009 (has links)
<p>Testing plays a very important role for assuring the quality of developed software. In a modern vehicle, more and more of the functionality is controlled by software and the complexity of the software always increases. The expectations on automating the testing process are to save time and to reach an even higher quality.</p><p>In this thesis, which was performed at ZF Friedrichshafen AG, a new tool for automated tests is studied. The tool is used for software in the loop simulation based system tests. The user specifies which outputs that shall be observed and which inputs that can be controlled. Based on these prerequisites, test cases are generated.</p><p>It has been studied how to apply the tool, how the test case generation can be influenced, on which systems it successfully could be used and which results that could be reached with the tool. The tool has been evaluated on the hand of two real-life examples; the software of an automatic transmission and of a pressure controller, a module of this software. It was found that there are many interesting possibilities to apply the tool in order to support the present testing process.</p>
3

Application of a New Software Tool for the Automated Test of Automotive Electronic Control Unit Software

Amlinger, Hanna January 2009 (has links)
Testing plays a very important role for assuring the quality of developed software. In a modern vehicle, more and more of the functionality is controlled by software and the complexity of the software always increases. The expectations on automating the testing process are to save time and to reach an even higher quality. In this thesis, which was performed at ZF Friedrichshafen AG, a new tool for automated tests is studied. The tool is used for software in the loop simulation based system tests. The user specifies which outputs that shall be observed and which inputs that can be controlled. Based on these prerequisites, test cases are generated. It has been studied how to apply the tool, how the test case generation can be influenced, on which systems it successfully could be used and which results that could be reached with the tool. The tool has been evaluated on the hand of two real-life examples; the software of an automatic transmission and of a pressure controller, a module of this software. It was found that there are many interesting possibilities to apply the tool in order to support the present testing process.
4

Modellbasierte Software in the Loop Simulation von Werkzeugmaschinen /

Herfs, Werner Josef. January 2010 (has links)
Zugl.: Aachen, Techn. Hochsch., Diss., 2010.
5

Desenvolvimento de uma plataforma para testes de controladores, em arquitetura de controle hardware in the loop, utilizando um hardware eletrônico externo e um software de simulação de voo / Development of a platform for controllers tests, in hardware in the loop control architecture, using an external electronic hardware and a flight simulation software

Cazarini, Eduardo 06 March 2015 (has links)
Essa dissertação tem por objetivo o desenvolvimento de uma plataforma para testes de controladores de voo. Tal plataforma consiste em um hardware executando algoritmos de controle e atuando numa aeronave simulada em software de simulação de voo. O software de simulação escolhido, baseado na experiência prática de pilotos profissionais, foi o Microsoft Flight Simulator (MSFS), para o qual desenvolveu-se o modelo gráfico e dinâmico do quadricóptero AscTec Pelican. A comunicação entre o MSFS e o hardware é feita pela interface USB através do software FVMS v2.0 desenvolvido em ambiente DELPHI® 7.0 exclusivamente para este trabalho. O FVMS é capaz de ler o estado das variáveis de voo no MSFS, enviá-las para o hardware externo executar o controle, receber os sinais de controle de volta e utilizá-los no MSFS. O projeto e execução do hardware externo com controlador dsPIC também foi realizado neste mesmo trabalho. A título de avaliação de desempenho, também foi implementado um controlador robusto do tipo H&#8734; linear, desenvolvido pela equipe ART (Aerial Robots Team) da Escola de Engenharia de São Carlos. O mesmo controlador também foi aplicado na arquitetura software in the loop, na qual o controle é executado dentro do próprio FVMS, para comparação de desempenho entre os dois sistemas. Ao término do trabalho, as características de desempenho do sistema como um todo ficam bem evidenciadas através dos testes de estabilidade com e sem distúrbios executados em ambas arquiteturas de controle. / This dissertation aims to develop a platform for flight controllers tests. It platform consists of an electronic hardware where the control\'s algorithms will be executed and a virtual aircraft is simulated in flight simulation software. The chosen simulation software, based on practical experience of professional pilots, was Microsoft Flight Simulator (MSFS). The graphic and dynamic model of quadrotor AscTec Pelican was developed to perform inside the software. The communication between the MSFS and the hardware is made by USB interface through FVMS v2.0 software developed in DELPHI® 7.0 environment, exclusively for this work. The FVMS can read the status of the flight variables in MSFS, send them to the external hardware, receive control signals back and write them in MSFS. The design and implementation of external hardware with dsPIC controller was also developed ons ame work. For performance evaluation of the system, it was also implemented a robust linear H&#8734; controller, developed by ART team (Aerial Robots Team) of the School of Engineering of São Carlos. The same controller was also applied using software in the loop architecture, in which the control is performed inside FVMS, to compare performance between the two architectures. In the end of the work, the performance characteristics of the systems were well evidenced by the stability tests carried out with and without disturbances in both control architectures.
6

Desenvolvimento de uma plataforma para testes de controladores, em arquitetura de controle hardware in the loop, utilizando um hardware eletrônico externo e um software de simulação de voo / Development of a platform for controllers tests, in hardware in the loop control architecture, using an external electronic hardware and a flight simulation software

Eduardo Cazarini 06 March 2015 (has links)
Essa dissertação tem por objetivo o desenvolvimento de uma plataforma para testes de controladores de voo. Tal plataforma consiste em um hardware executando algoritmos de controle e atuando numa aeronave simulada em software de simulação de voo. O software de simulação escolhido, baseado na experiência prática de pilotos profissionais, foi o Microsoft Flight Simulator (MSFS), para o qual desenvolveu-se o modelo gráfico e dinâmico do quadricóptero AscTec Pelican. A comunicação entre o MSFS e o hardware é feita pela interface USB através do software FVMS v2.0 desenvolvido em ambiente DELPHI® 7.0 exclusivamente para este trabalho. O FVMS é capaz de ler o estado das variáveis de voo no MSFS, enviá-las para o hardware externo executar o controle, receber os sinais de controle de volta e utilizá-los no MSFS. O projeto e execução do hardware externo com controlador dsPIC também foi realizado neste mesmo trabalho. A título de avaliação de desempenho, também foi implementado um controlador robusto do tipo H&#8734; linear, desenvolvido pela equipe ART (Aerial Robots Team) da Escola de Engenharia de São Carlos. O mesmo controlador também foi aplicado na arquitetura software in the loop, na qual o controle é executado dentro do próprio FVMS, para comparação de desempenho entre os dois sistemas. Ao término do trabalho, as características de desempenho do sistema como um todo ficam bem evidenciadas através dos testes de estabilidade com e sem distúrbios executados em ambas arquiteturas de controle. / This dissertation aims to develop a platform for flight controllers tests. It platform consists of an electronic hardware where the control\'s algorithms will be executed and a virtual aircraft is simulated in flight simulation software. The chosen simulation software, based on practical experience of professional pilots, was Microsoft Flight Simulator (MSFS). The graphic and dynamic model of quadrotor AscTec Pelican was developed to perform inside the software. The communication between the MSFS and the hardware is made by USB interface through FVMS v2.0 software developed in DELPHI® 7.0 environment, exclusively for this work. The FVMS can read the status of the flight variables in MSFS, send them to the external hardware, receive control signals back and write them in MSFS. The design and implementation of external hardware with dsPIC controller was also developed ons ame work. For performance evaluation of the system, it was also implemented a robust linear H&#8734; controller, developed by ART team (Aerial Robots Team) of the School of Engineering of São Carlos. The same controller was also applied using software in the loop architecture, in which the control is performed inside FVMS, to compare performance between the two architectures. In the end of the work, the performance characteristics of the systems were well evidenced by the stability tests carried out with and without disturbances in both control architectures.
7

Développement d'une plateforme de co-simulation en vue de validation et d'évaluation de performances des systèmes de communication pour les installations de distribution électriques / Co-Simulation Platform for performance evaluation of communication networks 'application for smart grid communication architecture'

Haffar, Mohamad 21 September 2011 (has links)
Un système de distribution électrique est le cœur de tous types de sites industriels, aussi bien les sites producteurs d'énergie que les sites consommateurs. La sécurité de ce système doit être impérativement assurée par la mise en place des unités assurant plusieurs fonctionnalités de protection contre les dédauts électriques. Parmi ces fonctionalités il existe celles qui se basent sur des échanges d'information entre plusieurs unités de protection. Le standard IEC 61850 guarantit cet échange des informations via des signaux ‘temps réel' échangé via le réseau de communication. Vue l'aspet non deterministe de ces signaux, une étude poussée de leur fiabilité doit être effectuée. Pour ces raisons notre travail de thèse a pour objectif de mettre en place une méthodologie, basée sur une plateforme de Co-Simulation conçue pendant notre étude, qui permet la validation de la fiabilité de ces messages tout au long du cycle de vie d'un système de communication IEC 61850. / From 2004, a new worldwide standard of communication IEC61850 is introduced in the majority of substation automation system carrying out new innovation prospects to the world of substation. One of these feature is that it allows the exchange of security real time communication messages all over the communication network. These messages are used as control information for the Distributed Automation Application 'DAA'. Taking into consideration that DAA have a direct effect on ythe dependability of a smart grid architecture, the fiability of these real time IEC 61850 should be evaluated. For these reasons, our research delas with the development of a Co-Simulation platform that permits the evaluation and validation of an IEC 61850 communication network.
8

Modeling and Assessment of State-Of-The-Art Traffic Control Subsystems

Mladenovic, Milos Novica 12 May 2011 (has links)
Traffic signals are one of the vital control elements of traffic management and control systems under purview of Departments of Transportation (DOTs) nationwide. They directly affect mobility, safety, and environmental parameters of the transportation networks. Traffic engineers in DOTs often face pressure for extracting additional benefits from existing signal control equipment, influenced by evident increase in demand and changing traffic patterns. However, they often face difficulties, usually from the maturity of the field equipment, lack of understanding of currently available equipment capabilities, and multitude of market available equipment. Besides issues in everyday operation, the need for improved decision-making process appears during selection and implementation of the future signal-control subsystems. This thesis is focusing on the issues related with the need for extracting additional benefits and improved planning of signal-control equipment deployment. Presented are several methodologies and techniques for modeling and assessing traffic signal controllers and supporting communication infrastructure. Techniques presented in this thesis include Petri Net modeling language, Software-in-the-loop simulation, and Geographical Information Systems. Specific capabilities of listed techniques are coordinated for maximizing their benefits in addressing specific issues. The intended positive effects reflect in enhanced comprehension, numerical representation, and analysis of state-of-the-art signal control subsystems in focus. Frameworks, methodologies, and example cases are presented for each of the specific issues in identified traffic signal subsystems, along with recommendations for further research. / Master of Science
9

Data-driven Target Tracking and Hybrid Path Planning Methods for Autonomous Operation of UAV

Choi, Jae-Young January 2023 (has links)
The present study focuses on developing an efficient and stable unmanned aerial system traffic management (UTM) system that utilizes a data-driven target tracking method and a distributed path planning algorithm for multiple Unmanned Aerial Vehicle (UAV) operations with local dynamic networks, which can provide flexible scalability, enabling autonomous operation of a large number of UAVs in dynamically changing environment. Traditional dynamic motion-based target tracking methods often encounter limitations due to their reliance on a finite number of dynamic motion models. To address this, data-driven target tracking methods were developed based on the statistical model of the Gaussian mixture model (GMM) and deep neural networks of long-short term memory (LSTM) model, to estimate instant and future states of UAV for local path planning problems. The estimation accuracy of the data-driven target tracking methods were analyzed and compared with dynamic model-based target tracking methods. A hybrid dynamic path planning algorithm was proposed, which selectively employs grid-free and -based path search methods depending on the spatio-temporal characteristics of the environments. In static environment, the artificial potential field (APF) method was utilized, while the $A^*$ algorithm was applied in the dynamic state environment. Furthermore, the data-driven target tracking method was integrated with the hybrid path planning algorithm to enhance deconfliction. To ensure smooth trajectories, a minimum snap trajectory method was applied to the planned paths, enabling controller tracking that remains dynamically feasible throughout the entire operation of UAVs. The methods were validated in the Software-in-the-loop (SITL) demonstration with the simple PID controller of the UAVs implemented in the software program. / Ph.D. / This dissertation focuses on developing data-driven models for tracking and path planning of Unmanned Aerial Vehicle (UAV) in dynamic environments with multiple operations. The goal is to improve the accuracy and efficiency of Unmanned Aircraft System traffic management (UTM) under such conditions. The data-driven models are based on Gaussian mixture model (GMM) and long-short term memory (LSTM) and are used to estimate the instant and consecutive future states of UAV for local planning problems. These models are compared to traditional target tracking models, which use dynamic motion models like constant velocity or acceleration. A hybrid dynamic path planning approach is also proposed to solve dynamic path planning problems for multiple UAV operations at an efficient computation cost. The algorithm selectively employs a path planning method between grid-free and grid-based methods depending on the characteristics of the environment. In static state conditions, the system uses the artificial potential field method (APF). When the environment is time-variant, local path planning problems are solved by activating the $A^*$ algorithm. Also, the planned paths are refined by minimum snap trajectory to ensure that the path is dynamically feasible throughout a full operation of the UAV along with controller tracking. The methods were validated in the Software-in-the-loop (SITL) demonstration with the simple PID controller of the UAVs implemented in the software program.
10

Virtual Test Cell : a Real-Time digital twin of an internal combustion engine

Malmqvist, Rasmus January 2024 (has links)
As the world is evolving faster and technology gets cheaper and more powerful, simulations are proving to be more and more beneficial. Simulations allow for faster development with less lead time between iterations which means that product versions can be released more often and at less cost. The automotive industry is heavily affected by emission legislation and environmental politics. The development of more environmentally friendly engines forces the rate of development to speed up. Simulations allow the industry to keep up with the increasing requests for more complex systems. For software development, it speeds up the process significantly. Although real-life testing in engine test cells and test cars still sets the foundation for and validates the results of the simulations, simulations can drastically decrease the amount needed. Less unnecessary real-life testing with bugs in the software causing wasted time and cost. In the meantime, more iterations can be tested in a smaller time frame, making the actual real-life testing more valuable and giving. The aim of this thesis is to develop a method to convert an accurate but relatively slow simulation model of the airflow through an engine, into a faster-running format preparing it to run in close to Real-Time and with a fixed timestep. Then exporting the converted model as a functional mock-up unit, FMU, a standardised entity, part of the Functional Mock-up Interface standard. The FMU was to be used in Software in Loop, SiL, simulations using it in cooperation with Matlab Simulink and Synopsys Silver. The SiL environment is then to be used to develop and test calibration software for the engine in question.

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