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Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xiii, 164 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 85-87).

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains xi, 118 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 102-103).

M.Phil (Engineering Management) / The importance of an effective maintenance programme cannot be over-emphasized because such a programme plays such an important role in the effectiveness of lean manufacturing. Maintenance may be considered the health care of any engineering equipment and its equipment. It is required to reduce waste effectively, and to run an efficient, continuous locomotive operation within a business or service operation. The cost of regular maintenance is very small when it is compared to the cost of a major breakdown at which time production is held up. The main purpose of regular maintenance is to ensure that all equipment required for production is operating at 100% efficiency at all times. Through short daily inspections, cleaning, lubricating, and making of minor adjustments, minor problems can be detected and corrected before they become major problems that can shut down a production line. A good maintenance programme requires company-wide participation and support by everyone from top executives to shop floor personnel (Dale, 2008) The function of reliability engineering is to develop the reliability requirements for a product, establish an adequate reliability programme, and perform appropriate analyses and tasks to ensure that the product meets its requirements. These tasks are managed by a reliability engineer who usually holds an accredited engineering degree and has additional reliability-specific education and training. Reliability engineering is closely associated with maintainability engineering and logistics engineering. Many problems from other fields can also be tackled using reliability engineering techniques (O’Connor 2010). Reliability is defined as the probability that a device will perform its required function under stated conditions for a specific period of time, and quality can be defined as how the recipient of the product or service views the product (Barringer, 2006). Therefore the two cannot be viewed differently as they both have the same focus which is the end result of the product’s performance. The findings reveal that customers should form part of reliability management systems; the development of ways to identify possible failure before it actually happens is key in achieving reliability targets; and training of key personnel on engineering and quality department as well as resource planning and utilization is a key towards eliminating reliability challenges.

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.

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

O presente trabalho tem por objetivo o desenvolvimento de um modelo analógico dinâmico do IGBT 2MBI1200U4G-170 para simulação SPICE para a análise de tempos de comutação, perdas e corrente de carga. Este desenvolvimento foi motivado pelo fato de não se dispor de modelos prontos para IGBT para faixas de tensão e corrente na ordem de kV e kA, destinado ao projeto de um conversor CC para controle de motores de tração em locomotivas diesel-elétricas. Como parte do processo se fez uma tentativa de modificação do modelo padrão de IGBT da plataforma Cadence Orcad 16.5, baseada nos trabalho de Hefner, considerada uma forma de modelo físico. Verificou-se que o correto levantamento dos dados para o modelo físico não seria compensatório frente às análises desejadas, o que gerou necessidade por outras formas de modelagem. Decidiu-se por um modelo analógico, obtido com dados do catálogo do componente descritos em tabelas e como fontes de tensão e corrente. Os resultados mostraram-se adequados para projeto térmico, análise de formas de onda e corrente de porta e coletor. A simulação é comparada com curvas da documentação do fabricante e com dados obtidos a partir de testes estáticos em laboratório com duas topologias. Testes foram feitos com tensão de entrada de 74V, 300V, 900V e 1000V, frequências de comutação de 200Hz, 416Hz, 1kHz e 2kHz e correntes de carga de até 1400A. A corrente de carga apresentou diferenças de até 3% com a medida em laboratório e a temperatura divergiu em até 7% com a medida no dissipador do protótipo usado. / This paper presents the design report for an analog IGBT SPICE model, part number 2MBI1200U4G-170. The modeling was perceived as a interesting tool in order to analyze the switching times and losses during the development, not performed at the University, of a chopper DC-DC converter used for current control of traction motors of diesel-electric locomotives. The main motivational factor was that an practical and quick approach was wanted and none standard model was found for the intended IGBT part number. As part of the process, an attempt to modify the standard SPICE model of the Cadence Orcad 16.5, which is a physics model based on Hefner works, was made. It was verified that the correct data collecting for the standard model would not be compensatory, so other modeling techniques were needed. It was decided an analog modeling would be used. The modeling achieved uses no more than the information found on the component datasheet described in tables format, voltage and current sources. The validation was done in two different topologies with load currents up to 1400A, switching frequencies of 200Hz, 416Hz, 1kHz and 2kHz and input voltages of 74V, 300V, 900V and 1000V . Comparatives were done with the vendor catalog and laboratory data. The model is satisfactory for heat, collector and gate currents analysis. The simulation current and temperature results showed differences up to 3% and 7%, respectively, when compared to laboratories measurements.

O presente trabalho tem por objetivo o desenvolvimento de um modelo analógico dinâmico do IGBT 2MBI1200U4G-170 para simulação SPICE para a análise de tempos de comutação, perdas e corrente de carga. Este desenvolvimento foi motivado pelo fato de não se dispor de modelos prontos para IGBT para faixas de tensão e corrente na ordem de kV e kA, destinado ao projeto de um conversor CC para controle de motores de tração em locomotivas diesel-elétricas. Como parte do processo se fez uma tentativa de modificação do modelo padrão de IGBT da plataforma Cadence Orcad 16.5, baseada nos trabalho de Hefner, considerada uma forma de modelo físico. Verificou-se que o correto levantamento dos dados para o modelo físico não seria compensatório frente às análises desejadas, o que gerou necessidade por outras formas de modelagem. Decidiu-se por um modelo analógico, obtido com dados do catálogo do componente descritos em tabelas e como fontes de tensão e corrente. Os resultados mostraram-se adequados para projeto térmico, análise de formas de onda e corrente de porta e coletor. A simulação é comparada com curvas da documentação do fabricante e com dados obtidos a partir de testes estáticos em laboratório com duas topologias. Testes foram feitos com tensão de entrada de 74V, 300V, 900V e 1000V, frequências de comutação de 200Hz, 416Hz, 1kHz e 2kHz e correntes de carga de até 1400A. A corrente de carga apresentou diferenças de até 3% com a medida em laboratório e a temperatura divergiu em até 7% com a medida no dissipador do protótipo usado. / This paper presents the design report for an analog IGBT SPICE model, part number 2MBI1200U4G-170. The modeling was perceived as a interesting tool in order to analyze the switching times and losses during the development, not performed at the University, of a chopper DC-DC converter used for current control of traction motors of diesel-electric locomotives. The main motivational factor was that an practical and quick approach was wanted and none standard model was found for the intended IGBT part number. As part of the process, an attempt to modify the standard SPICE model of the Cadence Orcad 16.5, which is a physics model based on Hefner works, was made. It was verified that the correct data collecting for the standard model would not be compensatory, so other modeling techniques were needed. It was decided an analog modeling would be used. The modeling achieved uses no more than the information found on the component datasheet described in tables format, voltage and current sources. The validation was done in two different topologies with load currents up to 1400A, switching frequencies of 200Hz, 416Hz, 1kHz and 2kHz and input voltages of 74V, 300V, 900V and 1000V . Comparatives were done with the vendor catalog and laboratory data. The model is satisfactory for heat, collector and gate currents analysis. The simulation current and temperature results showed differences up to 3% and 7%, respectively, when compared to laboratories measurements.