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The article identifies the challenges during the system and specifically the software development process for safety critical electro-hydraulic control systems by using the example of the hydrostatic driveline with a four speed transmission of a feeder mixer. An optimized development approach for mobile machinery has to fulfill all the requirements according to the Machinery Directive 2006/42/EC, considering functional safety, documentation and testing requirements from the beginning and throughout the entire machine life cycle. The functionality of the drive line control could be verified in advance of the availability of a prototype by using a “software-in-the-loop” development approach, based on a MATLAB/SIMULINK model of the drive line in connection with the embedded software.

Battery energy management plays a crucial role in fuel economy improvement of charge-sustaining parallel hybrid electric vehicles. Currently available control strategies consider battery state of charge (SOC) and driver’s request through the pedal input in decision-making. This method does not achieve an optimal performance for saving fuel or maintaining appropriate SOC level, especially during the operation in extreme driving conditions or hilly terrain. The objective of this thesis is to develop a control algorithm using forthcoming traffic condition and road elevation, which could be fed from navigation systems. This would enable the controller to predict potential of regenerative charging to capture cost-free energy and intentionally depleting battery energy to assist an engine at high power demand. The starting point for this research is the modelling of a small sport-utility vehicle by the analysis of the vehicles currently available in the market. The result of the analysis is used in order to establish a generic mild hybrid powertrain model, which is subsequently examined to compare the performance of controllers. A baseline is established with a conventional powertrain equipped with a spark ignition direct injection engine and a continuously variable transmission. Hybridisation of this vehicle with an integrated starter alternator and a traditional rule-based control strategy is presented. Parameter optimisation in four standard driving cycles is explained, followed by a detailed energy flow analysis. An additional potential improvement is presented by dynamic programming (DP), which shows a benefit of a predictive control. Based on these results, a predictive control algorithm using fuzzy logic is introduced. The main tools of the controller design are the DP, adaptive-network-based fuzzy inference system with subtractive clustering and design of experiment. Using a quasi-static backward simulation model, the performance of the controller is compared with the result from the instantaneous control and the DP. The focus is fuel saving and SOC control at the end of journeys, especially in aggressive driving conditions and a hilly road. The controller shows a good potential to improve fuel economy and tight SOC control in long journey and hilly terrain. Fuel economy improvement and SOC correction are close to the optimal solution by the DP, especially in long trips on steep road where there is a large gap between the baseline controller and the DP. However, there is little benefit in short trips and flat road. It is caused by the low improvement margin of the mild hybrid powertrain and the limited future journey information. To provide a further step to implementation, a software-in-the-loop simulation model is developed. A fully dynamic model of the powertrain and the control algorithm are implemented in AMESim-Simulink co-simulation environment. This shows small deterioration of the control performance by driver’s pedal action, powertrain dynamics and limited computational precision on the controller performance.

Aujourd’hui, la conception ne porte plus sur de simples objets, mais sur des systèmes complexes, sociotechniques et ouverts. Les systèmes de conduite de procédés font partie de ce type de systèmes, où les performances du système reposent sur l’optimisation conjointe des composantes humaines et techniques. Afin de limiter la détection d’erreur tardive, il devient alors important de pouvoir effectuer des tests tout au long de la conception, sans augmenter les coûts et les délais de conception. L’objectif de nos travaux est de faciliter l’intégration de techniques de vérification par simulation, dès le début de la conception, pour des systèmes de conduite de procédés de type gestion de fluide. Pour tenir compte du caractère adaptable du système et de son évolution dans un environnement dynamique, une première contribution porte sur la démarche de vérification, basée sur la formalisation et la contextualisation des propriétés à vérifier. Puis, afin de faciliter l’obtention des modèles de simulation du procédé nécessaires à la mise en œuvre des vérifications tout au long de la conception, nous proposons une approche de génération automatisée des modèles de simulation du procédé dans le langage Modelica (modélisation multi-domaine), à partir d’un schéma P&ID (représentation de l’architecture fonctionnelle du procédé) et d’une bibliothèque d’éléments (contenant les modèles de simulation des éléments). L’implémentation de cette approche dans le cadre du flot de conception automatisée de contrôle- commande d’Anaxagore permet d’apporter une preuve de concept et une preuve d’usage de nos propositions. / Nowadays, engineers have to design open, complex and sociotechnical systems. The process control systems belong to this class of systems, in which the system performance relies on the joint optimisation of technical components and human components. To avoid the late discovery of design errors, it is necessary to perform tests throughout the design without adding design costs and delays. The aim of this work is therefore to facilitate the integration of checking by simulation, from early design stage, for process control systems such as fluid management systems. Regarding the adaptable feature of the system and its evolution in a dynamic environment, a first contribution focusses on the verification approach, by modelling the requirements within the context. Then, to facilitate the obtaining of the process simulation models required for checking throughout the design, we propose an automatic generation approach of simulation models in Modelica language (multi-domain modelling), from a P&ID model (modelling of the functional architecture of the process) and a library of elements (containing the simulation models of elements). To provide a proof of concept and a proof of use of our proposals, this approach has been implemented into Anaxagore, an automated design flow for monitoring and control.

Battery energy management plays a crucial role in fuel economy improvement of charge-sustaining parallel hybrid electric vehicles. Currently available control strategies consider battery state of charge (SOC) and driver’s request through the pedal input in decision-making. This method does not achieve an optimal performance for saving fuel or maintaining appropriate SOC level, especially during the operation in extreme driving conditions or hilly terrain. The objective of this thesis is to develop a control algorithm using forthcoming traffic condition and road elevation, which could be fed from navigation systems. This would enable the controller to predict potential of regenerative charging to capture cost-free energy and intentionally depleting battery energy to assist an engine at high power demand. The starting point for this research is the modelling of a small sport-utility vehicle by the analysis of the vehicles currently available in the market. The result of the analysis is used in order to establish a generic mild hybrid powertrain model, which is subsequently examined to compare the performance of controllers. A baseline is established with a conventional powertrain equipped with a spark ignition direct injection engine and a continuously variable transmission. Hybridisation of this vehicle with an integrated starter alternator and a traditional rule-based control strategy is presented. Parameter optimisation in four standard driving cycles is explained, followed by a detailed energy flow analysis. An additional potential improvement is presented by dynamic programming (DP), which shows a benefit of a predictive control. Based on these results, a predictive control algorithm using fuzzy logic is introduced. The main tools of the controller design are the DP, adaptive-network-based fuzzy inference system with subtractive clustering and design of experiment. Using a quasi-static backward simulation model, the performance of the controller is compared with the result from the instantaneous control and the DP. The focus is fuel saving and SOC control at the end of journeys, especially in aggressive driving conditions and a hilly road. The controller shows a good potential to improve fuel economy and tight SOC control in long journey and hilly terrain. Fuel economy improvement and SOC correction are close to the optimal solution by the DP, especially in long trips on steep road where there is a large gap between the baseline controller and the DP. However, there is little benefit in short trips and flat road. It is caused by the low improvement margin of the mild hybrid powertrain and the limited future journey information. To provide a further step to implementation, a software-in-the-loop simulation model is developed. A fully dynamic model of the powertrain and the control algorithm are implemented in AMESim-Simulink co-simulation environment. This shows small deterioration of the control performance by driver’s pedal action, powertrain dynamics and limited computational precision on the controller performance.

Enabling vehicles to preempt the normal operation of traffic signals has the potential to improve the safety and efficiency of both the requesting vehicle and all of the other vehicles. Little is known about which strategy is the most effective to exit from preemption control and transition back to the traffic signals normal timing plan. Common among these traffic signal transition strategies is the method of either increasing or decreasing the cycle length of the signal timing plan, as the process followed to return to the coordination point of the effected signal timing plan, to coordinate its operation with adjacent traffic signals. This research evaluates commonly available transition strategies: best way, long, short, and hold strategies. The major contribution of this research is enhancing the methodology to evaluate the impacts of using these alternative transition strategies. Part of this methodology consists of the "software-in-the-loop" simulation tool which replicates the stochastic characteristics of traffic flow under different traffic volume levels. This tool combines the software from a traffic signal controller (Gardner NextPhase Suitcase Tester, version 1.4B) with a microscopic traffic simulation model (CORSIM, TSIS 5.2 beta version). The research concludes that a statistically significant interaction exists between traffic volume levels and traffic signal transition strategies. This interaction eliminates the ability to determine the isolated effects of either the transition strategies on average travel delay and average travel time, or the effects of changes in traffic volume levels on average travel delay and average travel time. Conclusions, however, could be drawn on the performance of different transition strategies for specific traffic volume levels. As a result, selecting the most effective transition strategy needs to be based on the traffic volume levels and conditions specific to each traffic signal or series of coordinated traffic signals. The research also concludes that for the base traffic volume and a 40% increase in traffic volume, the most effective transition strategies are the best way, long or hold alternatives. The best way was the most effective transition strategy for a 20% increase in traffic volume. The least effective strategy is the short transition strategy for both the base and 40% increase in traffic volume, and the long and short for a 20% increase in traffic volume. Further research needs to be conducted to assess the performance of different transition strategies in returning to coordinated operation under higher levels of traffic volume (e.g., approaching or exceeding congested flow regime), with varying cycle lengths, with different signal timing plans, and when different roadway geometric configurations (e.g., turn lanes, length of turn lanes, number of lanes, spacing between intersections) are present. / Ph. D.

For years the trend in the automotive industry has been toward more complex electronic control systems. The number of electronic control units (ECUs) in vehicles is ever increasing as is the complexity of communication networks among the ECUs. Increasing fuel economy standards and the increasing cost of fuel is driving hybridization and electrification of the automobile. Achieving superior fuel economy with a hybrid powertrain requires an effective and optimized control system. On the other hand, mathematical modeling and simulation tools have become extremely advanced and have turned simulation into a powerful design tool. The combination of increasing control system complexity and simulation technology has led to an industry wide trend toward model based control design. Rather than using models to analyze and validate real world testing data, simulation is now the primary tool used in the design process long before real world testing is possible. Modeling is used in every step from architecture selection to control system validation before on-road testing begins. The Hybrid Electric Vehicle Team (HEVT) of Virginia Tech is participating in the 2011-2014 EcoCAR 2 competition in which the team is tasked with re-engineering the powertrain of a GM donated vehicle. The primary goals of the competition are to reduce well to wheels (WTW) petroleum energy use (PEU) and reduce WTW greenhouse gas (GHG) and criteria emissions while maintaining performance, safety, and consumer acceptability. This paper will present systematic methodology for using model based design techniques for architecture selection, control system design, control strategy optimization, and controller validation to meet the goals of the competition. Simple energy management and efficiency analysis will form the primary basis of architecture selection. Using a novel method, a series-parallel powertrain architecture is selected. The control system architecture and requirements is defined using a systematic approach based around the interactions between control units. Vehicle communication networks are designed to facilitate efficient data flow. Software-in-the-loop (SIL) simulation with Mathworks Simulink is used to refine a control strategy to maximize fuel economy. Finally hardware-in-the-loop (HIL) testing on a dSPACE HIL simulator is demonstrated for performance improvements, as well as for safety critical controller validation. The end product of this design study is a control system that has reached a high level of parameter optimization and validation ready for on-road testing in a vehicle. / Master of Science

En esta tesis se hacen contribuciones a la simulación interactiva de motores de reluctancia autoconmutados desde la perspectiva de la ingeniería concurrente.En primer lugar, después de una breve introducción histórica, se sitúa el motor de reluctancia autoconmutado (SRM) en el marco de los accionamientos eléctricos y se introducen los principios básicos de la ingeniería concurrente utilizando el prototipado rápido de accionamientos eléctricos.En segundo lugar se presenta la constitución del accionamiento con SRM y sus principios de funcionamiento. Se especifican los antecedentes en el modelado de los SRM y se presenta un tratamiento original de las curvas de magnetización.Seguidamente se trata la simulación de los accionamientos eléctricos desde la perspectiva de la ingeniería concurrente. Tras estudiar la evolución de la simulación (analógica, numérica, analógica digital, multidisciplinar, física, etc.), se muestran los procedimientos de la ingeniería concurrente que parten del modelado del accionamiento con SRM usando las técnicas SIL (Software In the Loop) que permiten escoger y ajustar los controles más adecuados usando un prototipo virtual del accionamiento y que integra los procedimientos utilizados en las técnicas HIL (hardware in the loop), concretándose todo ello en una plataforma digital para el desarrollo de los accionamientos con SRM.A continuación se procede, después de hacer una descripción general del accionamiento programado, a detallar los programas utilizados en la simulación interactiva de los diferentes componentes (convertidor estático, detectores de posición, sensores de corriente, cargas, etc) del accionamiento completo con SRM, considerando diferentes estrategias de control (pulso único, control de corriente mediante histéresis y PWM) y condiciones de funcionamiento (régimen permanente, transitorios y faltas).Posteriormente, se diseña una plataforma para el desarrollo de accionamientos con SRM en tiempo real mediante un entorno de prototipado rápido. Esta plataforma es flexible modular y robusta permitiendo; configurar distintas topologías del convertidor, implementar distintas estrategias de control en tiempo real tanto para el convertidor como para el accionamiento, evitando los problemas habituales de prueba y ajuste, que tanto tiempo hacen perder en el diseño convencional de accionamientos, para centrar la atención y los esfuerzos en los conceptos y aspectos clave de los accionamientos con SRM.Una vez construida la plataforma de desarrollo, esta se utiliza para contrastar y validar los resultados obtenidos mediante la simulación SIL, constatándose además la capacidad de la plataforma para el desarrollo de accionamientos de SRM, así como sus ventajas para la enseñanza e investigación en este tipo de accionamientos. Finalmente, se enumeran las aportaciones realizadas, se presentan las conclusiones finales y se describen futuras líneas de investigación. / In this thesis, contributions are made to the interactive simulation of switched reluctance motors (SRMs) from the perspective of concurrent engineering.Firstly, after a brief introduction to the history of switched reluctance motors (SRMs), they are placed in the context of electric drives. The basic principles of concurrent engineering are then described by means of the rapid prototyping of electric drives.Secondly, the design of drives using SRMs and the principles behind their operation are presented. An overview of SRM modeling is given and an original treatment of magnetization curves is presented.Subsequently, the simulation of electric drives from the perspective of concurrent engineering is carried out. After a study of how simulation (analogical, numerical, analogical-digital, multidisciplinary and physical) has evolved, the procedures of concurrent engineering are demonstrated. The procedures start out by modeling drives with SRMs using SIL (software-in-the-loop) techniques. This makes it possible to choose and to fit the most suitable controls by using a virtual prototype of the drive and integrating the procedures used in HIL (hardware-in-the-loop) techniques. The final outcome is a digital platform for the development of drives using SRMs.After a general description of the drive, the programs used in the interactive simulation of the components (static converters, position detectors, current sensors, loads, etc.) of the complete drive with an SRM are described. Various strategies ranging from control (single pulse, control of current by means of hysteresis and PWM) to conditions of operation (permanent, transitory and faulty schemes) are also considered.A platform for the development of drives using SRMs in real time by means of rapid prototyping is designed. This platform is flexible, modular and robust, which makes it possible to configure different topologies for the converter and to implement different control strategies in real time for the converter and the drive. This avoids the habitual problems of testing and adjusting, which take up a great deal of time in conventional drive design, thus making it possible to focus on the drive's conceptual features.Once the development platform has been built, it is used to validate the results obtained by means of SIL simulation. The platform's capacity to contribute to the development of SRM drives and its advantages for teaching and research in this particular field are demonstrated.Finally, all the original contributions are put forward, the conclusions are presented and future lines of research are described.

The methods used today for the commissioning and validation of industrial machines requires theconstruction of physical prototypes. Those prototypes help the engineers to e.g. validate if theprogram code meant to control a machine works as intended. In recent years the development ofnew techniques for the commissioning and validation of industrial machines has changed rapidlythanks to the development of new software. The method used in this thesis is called simulationin the loop. Another method that can be benecial to use is hardware in the loop. Using thosemethods for the commissioning of a machine is called virtual commissioning. The simulation inthe loop method is used to simulate both the machine and the control system that operate thatmachine. This is called a digital twin, a virtual copy of the physical hardware and its control systemthat can be used without the need for a real prototype to be available.The software used in this thesis comes all from the company Siemens and those are TIA Portal,Mechatronics Concept Designer, SIMIT and PLCSim Advanced. By using those programs it waspossible to build a digital twin with rigid body dynamics and its control system of the industrialmodel that was given by the company Renholmen AB. This model contained all the necessarycomponents needed for a virtual commissioning project to be done without the need to be at thefactory oor.The results showed that it was possible to achieve a real time simulation, allowing the possibilityto trim the controller parameters without the need of a physical prototype. Design errors were alsofound thanks to the results of the simulation.This new technique has shown to be a useful tool due to most of the work could be done on a digitalmodel of the machine. Simulations can reduce the time to market for industrial machines and alsohelp engineers to validate and optimize the product at an early stage. This tool that can be usedto validate industrial machines before they are created.

The article identifies the challenges during the system and specifically the software development process for safety critical electro-hydraulic control systems by using the example of the hydrostatic driveline with a four speed transmission of a feeder mixer. An optimized development approach for mobile machinery has to fulfill all the requirements according to the Machinery Directive 2006/42/EC, considering functional safety, documentation and testing requirements from the beginning and throughout the entire machine life cycle. The functionality of the drive line control could be verified in advance of the availability of a prototype by using a “software-in-the-loop” development approach, based on a MATLAB/SIMULINK model of the drive line in connection with the embedded software.