An attempt was made to reduce fuel costs of a diesel-electric locomotive by operating the locomotive in a periodic manner, as opposed to operating at a constant velocity. The periodic operation consisted of accelerating the locomotive in a high throttle position and then deccelerating at a low throttle position. An SD40 Locomotive was modeled to test the periodic operation. The periodic operation was actually found to offer no improvement in fuel performance over that of constant velocity operation. A modification to the diesel engine that takes advantage of the periodic operation is suggested that will give a better fuel performance. The modification to the engine would not be possible with constant velocity operation. With the modification, the periodic operation was found to save fuel over the constant velocity operation. A controller was then designed to implement the periodic operation. The key component of the controller is an observer to determine unknown hill forces. The controller was found to work successfully. / M.S.

Thesis (Ph.D.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Ahmet Vecdet Arslan. / Ph.D.

No description available.

M.Ing. / The principal reasons for the development of a prototype improved control system are the high maintenance costs and unreliability of Spoomet's fleet of class 6E/6E1 resistor technology electric main line locomotives. These factors may largely be attributed to two fundamental shortcomings of the existing locomotive control systems, namely the lack of inherent feedback and application of inconsequent control practices during acceleration from standstill. The improved control system features the application of a rule based fuzzy controller, implementing human skill and experience to control tractive effort of a resistor technology main line locomotive. The aim of the fuzzy controller is to accelerate the train from standstill to approximately 35 km/h, smoothly and safely. The prototype fuzzy controller was implemented with a personal computer using an advanced fuzzy logic development system. A simulation model was developed for the locomotive and the load. This model was used to first test the structure of the controller and the initial rule blocks. Following the verification of the fuzzy rules on the simulation model, a relay interface was developed to implement the operation of the control system in coupled mode with the existing control system on a locomotive. The interactive fine-tuning and evaluation of the fuzzy rules were performed during this phase of the development. The test results include the successful evaluation of the prototype fuzzy controller under a variety of typical and "worst case" operating conditions, as well as under conditions of wheel slip. The industrialisation and long term considerations for continued development of the fuzzy logic controller are described in the conclusion.

No description available.

M.Ing. / Spoornet currently has a fleet of more than 1500 electric locomotives in service. The majority of electric locomotives are resistor controlled but there are many chopper as well as thyristor controlled locomotives which all incorporate direct current (dc) traction motors. In recent years Spoornet has also bought locomotives employing alternating current (ac) traction motors. Because locomotives are very expensive and the running costs are high it is important that these locomotives must be available and reliable. Most of the newer generation locomotives, which are the semiconductor controlled locomotives, must be in service for at least another 20 years. The availability and reliability are often influenced by delayed design problems as well as problems arising due to changes in the total system configuration. One way of solving these problems, or at least understanding them, is by employing computer simulations. The availability and reliability can also be improved by using new technologies which were not originally employed on the locomotives. By doing computer simulations the optimal solution can be obtained when introducing new technologies on the locomotive. A good example of this type of application within Spoornet is given in [6], where simulation models for high technology locomotives were developed which were suitable to be used in the assessment of electromagnetic compatibility between modern power electronic locomotives and the railway signaling system. However, these models are also suited to be used in other applications. These models make use of the ATP-EMTP simulation program.

Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 1980. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Includes bibliographical references. / by Li-Moon Wann. / M.S.

Thesis (doctoral)--Universität Erlangen.

Diesel locomotives provide versatility to the railway system as they do not depend on electric feeding. Worldwide they constitute important parts of locomotive fleets used for various tasks such as mainline services, shunting and terminal operations. The main drawbacks are emissions of CO2, NOx and other pollutants. The emissions to air are in general controlled by legislation. The European testing and approval procedure for locomotive engines is performed with the ISO 8178-F test cycle. It is alone meant to resemble all European locomotives. Good correlation was found between mainline operations and the ISO 8178-F test cycle. A good correlation was furthermore found between shunting operations and North American shunting test cycles. However, this thesis has shown that this results in inadequate description of for instance shunting operations. Typical characteristics for shunting are relatively high ratio of transient loading, low mean power output and high amount of idling. Therefore important aspects of diesel locomotive usage are thereby disregarded in certifications. Deficient correlation between test cycle and intended operations may lead to locomotives that are not properly optimised for the type of operation they are intended for. Improperly dimensioned and optimised locomotives cause impaired fuel economy and more emissions emitted. Many Swedish diesel locomotives are to a large extent used in shunting-like conditions in yards and industries for instance. Therefore, it is recommended to supplement the present ISO test cycle with a test cycle that includes the characteristic of shunting. Knowledge about duty cycles for specific operations can be of importance in locomotive acquisition, dimensioning of new locomotives or when estimating emissions and/or fuel consumption. It is essential to make proper dimensioning of propulsion systems as it can imply lower life cycle costs as well as fewer emissions. Appropriate dimensioning of the propulsion system is particularly important for non-conventional propulsion systems. If the application range of a test cycle is narrow, its emulating capability ought to be better at describing and representing the indented application. Today's test cycles state fractional power or torque as a function of engine speed. This may result in misleading duty cycles when the same kind of operation is undertaken with different locomotives that have widespread power ratings. A more powerful locomotive used for the very same load as a less powerful locomotive will result in a different duty cycle. Non-conventional propulsion systems are gaining popularity also in the railway industry where implementation of new technology usually is slow. Dual mode and hybrid systems are two examples. Related to test and duty cycles the build-up of these new propulsion systems change the prerequisites of the propulsion systems. From a duty cycle perspective it is reasonable to implement an additional test cycle for non-conventional propulsion systems if the popularity rises. / QC 20111115

Depuis un demi-siècle, le développement de la traction électrique ferroviaire en courant monophasé en France s'est appuyé sur les progrès réalisés aussi bien au niveau des installations fixes de traction qu'au niveau du matériel roulant. Toutefois, au cours des deux dernières décennies, l'augmentation du trafic et l'introduction de locomotives avec des chaines de traction innovantes ont été à l'origine de phénomènes électriques qui se sont avérés néfastes pour l'exploitation du système. Les premiers phénomènes observés ont été à l'origine de dégâts matériels à bord de locomotives. Il s'agissait de surtensions résultant d'une interaction défavorable entre l'impédance interne de l'infrastructure et les harmoniques générés par les engins moteurs équipés de redresseurs à thyristors. Plus récemment, suite à l'introduction massive d'engins équipés de redresseurs à absorption sinusoïdale de courant, un phénomène de modulation très basse fréquence de la tension caténaire est apparu et a provoqué la mise hors tension des locomotives voire la disjonction de la sous station alimentant le secteur concerné. Ceci constitue aujourd'hui un obstacle majeur à l'utilisation généralisée de la nouvelle technologie à bord des engins. Ces perturbations affectent l'exploitation du système en entrainant généralement des retards voire des annulations de circulation. Elles peuvent aussi dégrader la qualité d'énergie du réseau d'électricité amont à un niveau tel que la sous-station d'alimentation doit être déconnectée. La direction de l'ingénierie de la SNCF a donc pris des dispositions pour comprendre puis éviter l'apparition des phénomènes observés. Une collaboration interne entre le centre d'ingénierie du matériel et la division des installations fixes de traction électrique ainsi qu'un partenariat avec le LAPLACE ont été mis en place. Le présent document est le fruit de cette collaboration. L'objectif de cette thèse est donc d'étudier et de modéliser les interactions entre les engins et les installations fixes de traction sur le réseau français 25kV/50Hz. Ce manuscrit comporte deux parties principales qui s'organisent ainsi : La première partie est consacrée à l'étude du phénomène de modulation très basse fréquence de la tension caténaire. Les modèles des deux principaux composants du système sont d'abord présentés. Les études ainsi menés permettent de comprendre l'origine du phénomène, puis ensuite de développer une méthode de caractérisation des engins permettant de retrouver les limites de stabilité dans les secteurs problématiques du réseau ferré. Ceci nous a conduit à proposer une représentation générale des locomotives modernes sous forme d'une matrice admittance qu'il est possible d'obtenir par une mesure directe sur des engins réels. La deuxième partie concerne l'étude des interactions harmoniques à l'origine de surtensions sur la caténaire. L'analyse systématique du phénomène est basée sur des outils de simulation de circuits électroniques de puissance utilisant une bibliothèque de modèles élémentaires. La première étape consiste à développer un modèle « moyenne fréquence » du réseau d'alimentation afin de mettre en évidence les fréquences de résonance de l'ensemble ligne/sous-station. La deuxième étape consiste à modéliser les locomotives afin de prendre en compte leur réponse harmonique. Au final, il devient possible de savoir si un engin donné va générer des déformations de la tension en vérifiant si l'une des composantes harmoniques du courant absorbé coïncide avec une des résonances caractéristique du circuit d'alimentation. Pour compléter cette deuxième partie, une modélisation plus fine, intégrant l'effet de peau et l'effet de proximité est abordée. Elle s'appuie sur la caractérisation expérimentale en moyenne fréquence d'un transformateur 50Hz. Ceci nous permet de vérifier l'influence de ces phénomènes sur le comportement fréquentiel du réseau d'alimentation. / For a half a century, the increasing development of AC electrical traction railway networks in France relied on the progress made in the infrastructure power supply an in the rolling stock. However, over the past two decades, increased traffic and the introduction of modern locomotives were the cause of electrical phenomena that have proven harmful to the operation of the railway network. The first events that occurred induced serious faults on board locomotives. It was overvoltages resulting from unfavourable interaction between the internal impedance of the infrastructure and the harmonics generated by the electrical vehicles using thyristor controlled rectifiers. More recently, with the massive introduction of active front-end locomotives, problems of low frequency oscillations and instability were observed causing power off locomotives or disjunction of the sector sub-station. The objective of this thesis is to study and model the interactions between locomotives and fixed installations for electric traction on the French rail network 25kV/50Hz. This script has two main parts, which organized as follows: The first part is devoted to the study of the phenomenon of very low frequency modulation of the catenary voltage. The models of the two main components of the system, namely the single-phase power and the active front-end locomotives are first presented. Studies conducted this way, help to understand the origin of the phenomenon and then to develop a method to characterize the vehicle to find the stability limits in problems sectors of the rail network. This led us to propose a general representation of modern locomotives as an admittance matrix that can be obtained by direct measurement on real machines. The second part is the study of harmonic interactions causing overvoltages on the catenary. Systematic analysis of the phenomenon is based on simulation tools of power electronics circuits using a collection of specific elementary models. The first step consists in developing a “medium frequency” model of the power network in order to highlight the resonance and anti-resonance frequencies of the line/sub-station set. The second step is to model locomotives to take into account their harmonic response. In the end, it becomes possible to know whether a particular machine will generate deformations of the catenary voltage, by checking if any of the harmonic components of the consumed current coincides with one of the characteristic resonances of the traction electric circuit. To complete the second part, a more detailed model is discussed incorporating physical phenomena that occur with an increasing frequency (skin effect in the insulted conductors or proximity effect between conductors).It is based on the experimental characterization on medium frequency of a 50Hz transformer. This allows us to check the influence of these phenomena on the frequency behaviour of the supply network.