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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.
51

Hardware-in-the-loop simulation of hybrid hydromechanical transmissions

Larsson, Viktor, Ericson, Liselott, Krus, Petter 23 June 2020 (has links)
Increased demands on fuel-efficient propulsion motivate the use of complex hybrid hydromechanical transmissions in heavy construction machines. These transmissions offer attractive fuel savings but come with an increased level of complexity and dependency on computer-based control. This trend has increased the use of computer-based simulations as a cost-effective alternative to hardware prototyping when developing and testing control strategies. Hardware-In-the-Loop (HWIL) simulations that combine physical and virtual model representations of a system may be considered an attractive compromise that combine the benefits of these two concepts. This paper explores how HWIL simulations may be used to evaluate powertrain control strategies for hybrid hydromechanical transmissions. Factors such as hardware/software partitioning and causality are discussed and applied to a test rig used for HWIL simulations of an example transmission. The results show the benefit of using HWIL simulations in favour of pure offline simulations and prototyping and stress the importance of accurate control with high bandwidth in the HWIL interface.
52

Hardware-in-the-loop Simulation of a Pumping Station : Design and implementation of a Python-based simulation program / Hardware-in-the-loop-simulering av en Pumpstation : Design och implementering av ett Python-baserat simuleringsprogram

Liang, Katrina January 2022 (has links)
The use of simulation enables testing of a system without the need for a complete physical system, while also having the advantages of lower cost and fewer practical limits compared to field tests. Hardware may be integrated into the simulation loop, such a simulation is defined as a Hardware-in-the-loop (HIL) simulation. The pump is the most energy-consuming part of a pumping station, thus improvement and assessment of the pump controller are two of the main considerations in the development of pumping stations. Nevertheless, the developers do not always have access to a real pumping station to run tests on. A HIL simulator that imitates parts of a pumping station while including a real controller in the simulation is therefore desirable for the development of pump controllers.In this thesis, a mathematical model of a pumping station was built based on the physical features of different components, and a HIL simulation was implemented with the programming language Python, in which a real controller was integrated into the simulation loop. Through a three-hour-long simulation run, the functionality of the simulator has been analyzed, and the simulation accuracy was evaluated by comparing simulated results to real data. The results showed that among the 10 800 simulated data points of the water level, there were \(43\) (\(\approx 0.39\%\)) that had a relative change larger than \(30\%\) or less than \(-30\%\) with respect to the field data. This thesis contributes to the field of Python-based simulation of a pumping station, and serves as a foundation for future improvement for the host company. / Användningen av simulering möjliggör testning av ett system utan ett komplett fysiskt system, till en lägre kostnad och färre praktiska begränsningar jämfört med fälttester. Hårdvara kan integreras i simuleringsloopen, en sådan simulering kallas för en hardware-in-the-loop (HIL) simulering. Pumpen är den mest energikrävande delen i en pumpstation, därför är förbättring och utvärdering av pumpstyrningen två av de viktigaste faktorerna vid utvecklingen av pumpstationer. Dock har utvecklarna inte alltid tillgång till en fysisk pumpstation att köra tester på. En HIL-simulator som imiterar delar av en pumpstation, till vilken en pumpstyrning kan kopplas, är därför önskvärd för utvecklingen av pumpstyrningar.I detta examensarbete konstruerades en matematisk modell av en pumpstation utifrån de fysiska egenskaperna hos olika komponenter. En HIL-simulator var sedan implementerad i programmeringsspråket Python, där en riktig pumpstyrning integrerades i simuleringsloopen. Genom en tre timmar lång körning har simulatorns funktionalitet analyserat, och simuleringsnoggrannheten utvärderades genom att jämföra simulerade resultat med verkliga data. Resultaten visade att \(43\) av de 10 800 (\(\approx 0,39\%\)) simulerade datapunkterna för vattennivån hade en relativ förändring större än \(30\%\) eller mindre än \(-30\%\) med avseende på fältdata. Detta arbete bidrar till området inom Python-baserad simulering av en pumpstation och agerar som en grund för framtida utvecklingar hos värdföretaget.
53

Multi-operated HIL Test Bench for Testing Underwater Robot’s Buoyancy Variation System

Gafurov, Salimzhan A., Reshetov, Viktor M., Salmina, Vera A., Handroos, Heikki 03 May 2016 (has links) (PDF)
Nowadays underwater gliders have become to play a vital role in ocean exploration and allow to obtain the valuable information about underwater environment. The traditional approach to the development of such vehicles requires a thorough design of each subsystem and conducting a number of expensive full scale tests for validation the accuracy of connections between these subsystems. However, present requirements to cost-effective development of underwater vehicles need the development of a reliable sampling and testing platform that allows the conducting a preliminary design of components and systems (hardware and software) of the vehicle, its simulation and finally testing and verification of missions. This paper describes the development of the HIL test bench for underwater applications. Paper discuses some advantages of HIL methodology provides a brief overview of buoyancy variation systems. In this paper we focused on hydraulic part of the developed test bench and its architecture, environment and tools. Some obtained results of several buoyancy variation systems testing are described in this paper. These results have allowed us to estimate the most efficient design of the buoyancy variation system. The main contribution of this work is to present a powerful tool for engineers to find hidden errors in underwater gliders development process and to improve the integration between glider’s subsystems by gaining insights into their operation and dynamics.
54

DESIGN AND DEVELOPMENT OF A FIBER OPTIC TELEMETRY PACKAGE

Griffith, Jerry A., Rowan, Herman K., Huber, August J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The Guided Weapons Evaluation Facility (GWEF) at Eglin Air Force Base is the Air Force’s premiere munitions hardware-in-the-loop (HITL) simulation facility. HITL simulation testing is a ground based tool used to evaluate the performance of a weapon system at a fraction of the cost of free flight testing. The weapon system is stimulated in a laboratory setting with the electromagnetic environment and physical motion it would experience in an operational setting. The system’s responses to that environment are measured to provide various measures of performance including target tracking ability and miss distance. Electrical interfaces are required in order to control the weapon’s guidance system and to receive and inject signals from the HITL simulation computer system to the weapon under test. These interfaces are usually developed using external control circuits and copper cabling to the guidance unit. The GWEF had a requirement to develop a missile interface with no external copper wires or antennas to support a unique test configuration. The requirement led to the development of a Fiber Optic Telemetry (FOTM) package which would be contained completely within the missile body cavity. The constraints on the FOTM design were considerable. Lack of a suitable commercial off-the-shelf fiber optic telemetry package led to the eventual in house design and fabrication of the FOTM. This paper describes the requirements, design constraints and results achieved in the FOTM design. Although not classical telemetry it does share similarities with conventional telemetry units used for open air weapons testing including size constraints, data rates and thermal considerations.
55

THE USE OF TELEMETRY IN AN ELECTROMAGNETIC TEST ENVIRONMENT

Papich, William J. 10 1900 (has links)
International Telemetering Conference Proceedings / October 25-28, 1999 / Riviera Hotel and Convention Center, Las Vegas, Nevada / The U.S. Army Redstone Technical Test Center (RTTC) uses telemetry as a vital part of its data acquisition and analysis for electromagnetic environmental effects developmental testing of U.S. Army weapon systems. Testing in an electromagnetic environment poses several unique challenges. These challenges have resulted in the development of highly customized telemetry and data acquisition systems. This paper discusses the design and integration of past and current telemetry needs to incorporate real-time or near real-time simulations or scene generations into the testing process.
56

Real-time Simulation of Modular Multilevel Converters

Dominic, Paradis 09 December 2013 (has links)
This thesis presents the real-time simulation of a realistic-size Modular Multilevel Converter (MMC) based High-Voltage Direct Current (HVDC) transmission system. Based on the concept of time-varying Thevenin equivalent, a computationally efficient model of the MMC is developed and deployed on an FPGA platform. The salient features of the developed MMC model are: (i) The decoupling of the solutions of the MMC model and the of the rest of the system, (ii) it provides an equivalent representation of the full MMC, (iii) it is suitable for parallel implementation. The model is used as part of the simulation of the 401-level France/Spain MMC-HVDC link between, in which 2 separate MMCs are included, showing the expandability of the designed system to larger DC grid scenarios. Hardware in the loop (HIL) testing capabilities of the system are also demonstrated with the addition of an external controller to the simulation system.
57

Real-time Simulation of Modular Multilevel Converters

Dominic, Paradis 09 December 2013 (has links)
This thesis presents the real-time simulation of a realistic-size Modular Multilevel Converter (MMC) based High-Voltage Direct Current (HVDC) transmission system. Based on the concept of time-varying Thevenin equivalent, a computationally efficient model of the MMC is developed and deployed on an FPGA platform. The salient features of the developed MMC model are: (i) The decoupling of the solutions of the MMC model and the of the rest of the system, (ii) it provides an equivalent representation of the full MMC, (iii) it is suitable for parallel implementation. The model is used as part of the simulation of the 401-level France/Spain MMC-HVDC link between, in which 2 separate MMCs are included, showing the expandability of the designed system to larger DC grid scenarios. Hardware in the loop (HIL) testing capabilities of the system are also demonstrated with the addition of an external controller to the simulation system.
58

Implementação de plataforma de simulação hardware-in-the-loop ABS para aplicações didáticas. / Implementation of ABS hardware-in-the-loop simulation platform for didactic applications.

Santos Junior, Aguinaldo Batista dos 18 April 2017 (has links)
A utilização de plataformas HIL (Hardware-in-the-loop) tem aumentado dentro do processo de desenvolvimento de ECU\'s em indústrias do ramo automotivo. A principal justificativa para tal aumento é a utilização da metodologia de desenvolvimento baseada em modelo, a qual integra a técnica HIL como um de seus principais pilares, possibilitando redução no tempo e custos de desenvolvimento de uma ECU. Quando aplicada a validação de sistemas de controle de freios, a simulação HIL possui vital importância, pois permite a prévia visualização de efeitos diretamente relacionados à dinâmica veicular, os quais somente podiam ser analisados através da realização de testes em pistas. No entanto, os benefícios da simulação HIL não se restringem somente as aplicações industriais. A possibilidade de análise dos efeitos produzidos por um módulo eletrônico de controle através de simulações cria um campo para a utilização da técnica HIL como uma ferramenta efetiva no ensino de sistemas eletrônicos veiculares. Neste trabalho demonstra-se a implementação de uma plataforma HIL ABS para aplicações didáticas. Esta plataforma é implementada incluindo o uso de um circuito elétrico para emulação de cargas e aquisição de sinais, de uma interface com entradas e saídas reconfiguráveis, de uma ECU ABS e de um computador de simulação, o qual executa os softwares de manipulação de dados e de simulação de dinâmica veicular. Os resultados obtidos através de simulações realizadas com a plataforma desenvolvida são comparados com resultados de testes reais, validando desta forma o modelo proposto. / The HIL (Hardware-in-the-loop) platforms utilization has increased within the development process of ECUs in the automotive industry. The main reason for this increase is the usage of the model based development methodology, which integrates the HIL technique as one of its main pillars, allowing a reduction in the time and costs of developing an ECU. When applied to the validation of brake control systems, HIL simulation has a vital importance, since it allows a prior visualization of effects directly related to the vehicle dynamics, which could only be analyzed by performing track tests. However, the benefits of HIL simulation are not only restricted to the industrial applications. The possibility of analyzing the effects produced by an electronic control module through simulations creates a field for the use of the HIL technique as an effective tool for teaching vehicular electronic systems. This work demonstrates the implementation of an ABS HIL platform for didactic applications. This platform is implemented including the usage of an electrical circuit for loads emulation and signals acquisition, an interface with reconfigurable inputs and outputs, an ABS ECU and a simulation computer, which runs the data manipulation and vehicle dynamic simulation softwares. The results obtained through the performed simulations with the developed platform are compared with actual test results, validating therefore the proposed model.
59

Modèles à échelle réduite en similitude pour l'ingénierie système et l'expérimentation simulée "temps compacté" : application à un microréseau incluant un stockage électrochimique.

Varais, Andy 10 January 2019 (has links) (PDF)
Cette thèse a été réalisée en collaboration avec la société SCLE SFE (Groupe ENGIE) et le laboratoire Laplace. Elle porte sur le développement d’une méthodologie permettant d’élaborer des modèles dits « en similitude », à échelle de puissance et de temps réduites. Ces modèles peuvent servir pour l’analyse des systèmes mais ils sont en particulier utiles pour l’expérimentation en temps réel des systèmes énergétiques. En effet, les expérimentations sont très souvent menées à échelle réduite pour des questions de taille, de coût,… Certaines parties de ces expérimentations peuvent être « émulées » (simulées physiquement par des dispositifs de puissance) d’autres étant constitués de composants physiques : on parle alors de procédure Hardware in the Loop (HIL). Même si, à la base, la démarche de réduction d’échelle a une portée générale, notre gamme d’application principale concerne les micro réseaux avec intégration de sources renouvelables intermittentes couplées à des composants de stockage. En conséquence,nos travaux se focalisent sur la mise en œuvre de modèles de similitudes en puissance/énergie/temps de sources ENR et de stockeurs. La notion de réduction de temps, nous parlerons de « temps virtuel compacté », est un des concepts clés de ces travaux. Une attention particulière est portée sur le développement d’un émulateur physique de batterie électrochimique.En effet, le stockage d’énergie est un point clé dans un micro réseau. De plus, cet élément présente de fortes non-linéarités dont la mise en similitude doit impérativement tenir compte et n’est pas triviale. Une fois ces modèles développés, on les éprouve via la mise en œuvre d’essais en expérimentation simulée par émulateurs physiques à échelle de puissance réduite et en temps virtuel compacté. Ces essais permettent par ailleurs de confronter les notions d’émulateurs «copie-modèle », pour lequel un modèle est utilisé pour reproduire le comportement du système, et d’émulateurs « copie-image », où le comportement du système est reproduit à partir d’un de ses composants réels (par exemple une cellule pour la batterie).
60

Gestion d’énergie de véhicules multi-sources électriques et hybrides au travers de la représentation énergétique macroscopique / Energy management of multi-sources electric and hybrid vehicles using energetic macroscopic representation

Castaings, Ali 31 May 2016 (has links)
Les véhicules routiers sont à une étape majeure de leur histoire. Face aux enjeux actuels d’ordre économiques et environnementaux, le véhicule routier du futur se doit d’être le moins énergivore et avoir une empreinte environnementale la plus réduite possible. Les véhicules multi sources représentent des solutions intéressantes afin de répondre à ces préoccupations. Cependant, ces véhicules utilisent des systèmes de propulsion particulièrement complexes tant au niveau de leur architecture que de leur commande. En particulier, la gestion des différentes sources d’énergie représente un point clé pour l’efficacité énergétique et environnementale des véhicules à concevoir. Elle devient un réel challenge dès que l’on dépasse le nombre usuel de deux sources comme dans le cas des véhicules hybrides actuels et des véhicules électriques mixtes (batterie et supercondensateurs). L’objectif des travaux relatifs à cette thèse est de proposer une méthodologie structurée pour la synthèse de la gestion d’énergie en temps réel, de véhicules multi-sources électriques ou hybrides. Cette démarche s’appuie sur une approche systémique utilisant la modélisation et la Représentation Energétique Macroscopique (REM) en tant qu’outil d’aide à la synthèse des modèles et de la commande associée. Une démarche systématique pour la synthèse des stratégies basées sur la commande optimale a été ensuite associée à cet ensemble profitant de la REM comme outil structurant. En effet, la REM respectant la causalité « physique » (causalité intégrale) d’une part, et permettant d’effectuer une distinction claire entre la commande dite « locale » et le niveau « stratégie » d’autre part, la formulation du problème de commande optimale est réalisée de manière efficace et structurée. Ainsi, en partant du cas du véhicule électrique avec un système multi-source batterie/supercondensateurs déjà étudiée dans la littérature, la méthode a été appliquée pour la synthèse d’une loi de gestion d’énergie basée sur la commande optimale. Ensuite, des sources ont été rajoutées pour passer au cas de trois sources en incluant une Pile à combustible puis quatre sources en rajoutant un groupe électrogène. Les principes développés sont validés par simulation et par l’intermédiaire de tests expérimentaux, afin de s’assurer entre autres, de la faisabilité en temps réel des stratégies développées. / Road vehicles are at a turning point of their history. In order to face economic and environmental challenges, road vehicle of the future must be less energy-consuming and less polluting. Multi sources vehicles represent interesting solutions in order to comply with these challenges. However, these vehicles use particularly complex propulsion systems, both on the architecture level and the control level. The management of the different energy sources represents a key issue for the energy efficiency of the vehicles to be designed. It becomes a real challenge as soon as one exceeds the usual number of two sources, as in current hybrid vehicles and mixed electric vehicles (battery and supercapacitors). The objective of the works relative to this thesis is to propose a structured method for the synthesis the energy management in real time, of electric or hybrid multi-sources vehicles. This approach is based on a systemic approach using the modeling and Energetic Macroscopic Representation (EMR) as a tool of assistance to the synthesis of the models and the related control. A systematic way for the synthesis of the strategies based on optimal control, has been associated benefitting from EMR tool. Indeed, EMR respecting “physical” causality (integral causality) on the one hand, and giving a clear distinction between the control level known as “local” and the “strategy” level on the other hand, the formulation of the optimal control problem is carried out and efficiently structured. Thus, on the basis of the electric vehicle case with a multi-source system battery/supercapacitors already studied in the literature, the method was applied for the synthesis of an energy management law based on the optimal control. Then, sources were added to pass to the case of three sources by including a Fuel cell, then four sources by adding a generator set. The developed principles are validated by simulation and experimental tests, in order to assess the feasibility in real time of the developed strategies.

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