Spelling suggestions: "subject:"auxiliar systems""
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Resonant DC link converters and their use in rail traction applicationsEllams, Philip January 1994 (has links)
Conventional 'hard switching' converters suffer from significant switching loss due to the simultaneous imposition of high values of current and voltage on the devices during commutation. Resonant converters offer a solution to this problem. A review of resonant circuit topologies is presented, which includes a summary of the interference problems which may occur when using power converters in the rail traction environment. Particular attention is given to the Resonant DC Link Inverter (RDCLI) which shows a great deal of pronuse using currently available devices. The frequency domain simulation of RDCLIs is discussed as a means of rapidly evaluating circuit behaviour, especially in relation to modulation strategies. A novel modulation strategy is proposed for Resonant DC Link Inverters, based on a procedure known as Simulated Annealing which allows complex harmonic manipulations such as han-nonic minimisation, to be performed. This is despite the fact that RDCLIs are constrained to use Discrete Pulse Modulation whereby switch commutations are restricted to specific moments in time. The modulation algorithms were verified by use of a low-power test rig and the results obtained are compared against theoretical values. Details of the hardware implementation are also included. A single-phase pulse-converter input stage is described which may be incorporated into the Resonant DC Link Inverter topology. This input stage also benefits from soft-sVVItching and allows four-quadrant operation at any desired power factor. A modulation scheme based on SiMulated Annealing is proposed for the pulse-converter, to achieve hannomc control whilst also synchronising with the supply wavefon-n. Practical results are presented and compared with those obtained by simulation and calculation. Finally the design of Resonant DC Link Converters is discussed and reconunendations made for the choice of resonant components based on the minimisation of overall losses. Comparisons are made between hard-switching and soft-switching converters in terms of loss and harmonic performance, in an attempt to quantify the benefits which may be obtained by the application of soft-switching.
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On design methods for mechatronics : servo motor and gearheadRoos, Fredrik January 2005 (has links)
<p>The number of electric powered sub-systems in road-vehicles is increasing fast. This development is primarily driven by the new and improved functionality that can be implemented with electro-mechanical sub-systems, but it is also necessary for the transition to electric and hybrid-electric drive trains.</p><p>An electromechanical sub-system can be implemented as a physically integrated mechatronic module: controller, power electronics, electric motor, transmission and sensors, all integrated into one component. A mechatronic module, spans, as all mechatronic systems, over several closely coupled engineering disciplines: mechanics, electronics, electro-mechanics, control theory and computer science. In order to design and optimize a mechatronic system it is therefore desirable to design the system within all domains concurrently. Optimizing each domain or component separately will not result in the optimal system design. Furthermore, the very large production volumes of automotive sub-systems increase the freedom in the mechatronics design process. Instead of being limited to the selection from off-the shelf components, application specific components may be designed.</p><p>The research presented in this thesis aims at development of an integrated design and optimization methodology for mechatronic modules. The target of the methodology is the conceptual design phase, where the number of design parameters is relatively small. So far, the focus has been on design methods for the electric motor and gearhead, two of the most important components in an actuation module. The thesis presents two methods for design and optimization of motor and gearhead in mechatronic applications. One discrete method, intended for the selection of off-the-shelf components, and one method mainly intended for high volume applications where new application specific components may be designed. Both methods can handle any type of load combination, which is important in mechatronic systems, where the load seldom can be classified as pure inertial or constant speed.</p><p>Furthermore, design models relating spur gear weight, size and inertia to output torque and gear ratio are presented. It is shown that a gearhead has significantly lower inertia and weight than a motor. The results indicate that it almost always is favorable from a weight and size perspective to use a gearhead. A direct drive configuration may only be lighter for very high speed applications. The main contribution of this thesis is however the motor/gear ratio sizing methods that can be applied to any electromechanical actuation system that requires rotational motion.</p>
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On design methods for mechatronics : servo motor and gearheadRoos, Fredrik January 2005 (has links)
The number of electric powered sub-systems in road-vehicles is increasing fast. This development is primarily driven by the new and improved functionality that can be implemented with electro-mechanical sub-systems, but it is also necessary for the transition to electric and hybrid-electric drive trains. An electromechanical sub-system can be implemented as a physically integrated mechatronic module: controller, power electronics, electric motor, transmission and sensors, all integrated into one component. A mechatronic module, spans, as all mechatronic systems, over several closely coupled engineering disciplines: mechanics, electronics, electro-mechanics, control theory and computer science. In order to design and optimize a mechatronic system it is therefore desirable to design the system within all domains concurrently. Optimizing each domain or component separately will not result in the optimal system design. Furthermore, the very large production volumes of automotive sub-systems increase the freedom in the mechatronics design process. Instead of being limited to the selection from off-the shelf components, application specific components may be designed. The research presented in this thesis aims at development of an integrated design and optimization methodology for mechatronic modules. The target of the methodology is the conceptual design phase, where the number of design parameters is relatively small. So far, the focus has been on design methods for the electric motor and gearhead, two of the most important components in an actuation module. The thesis presents two methods for design and optimization of motor and gearhead in mechatronic applications. One discrete method, intended for the selection of off-the-shelf components, and one method mainly intended for high volume applications where new application specific components may be designed. Both methods can handle any type of load combination, which is important in mechatronic systems, where the load seldom can be classified as pure inertial or constant speed. Furthermore, design models relating spur gear weight, size and inertia to output torque and gear ratio are presented. It is shown that a gearhead has significantly lower inertia and weight than a motor. The results indicate that it almost always is favorable from a weight and size perspective to use a gearhead. A direct drive configuration may only be lighter for very high speed applications. The main contribution of this thesis is however the motor/gear ratio sizing methods that can be applied to any electromechanical actuation system that requires rotational motion. / QC 20101220
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Energy use in the operational cycle of passenger rail vehicles / Energianvändning i passagerarjärnvägsfordons driftcykelVinberg, Erik Magni January 2018 (has links)
This master thesis investigates and analyzes the energy use for traction and auxiliary equipment in passenger rail vehicles. It covers both the train service with passengers and when the trains are going through other stages in the everyday operation. The operational cycle and associated operational situations are introduced as a way of describing the varying use of a train over time. The descriptions focus on the most common activities and situations, such as stabling and parking, regular cleaning, inspections and maintenance. Also how these situations affect energy use by their need for different auxiliary systems to be active. An energy model is developed based on the operational cycle as a primary input, together with relevant vehicle parameters and climate conditions. The latter proving to be a major influence on the energy used by the auxiliary equipment. The model is applied in two case studies, on SJ's X55 and Västtrafik's X61 trains. Both are modern electric multiple units equipped with energy meters. Model input is gathered from available technical documentation, previous studies and by measurements and parameter estimations. Operational cycle input is collected through different planning systems and rolling stock rosters. Climate input is finally compiled from open meteorological data banks. The results of the case studies show that the method and models are useful for studying the energy used by the trains in their operational cycles. With the possibility to distinguish the energy used by the auxiliary equipment, both during and outside the time the trains are in service with passengers. With this it's also possible to further investigate and study potential energy saving measures for the auxiliary equipment. Simulations of new ventilation control functions and improved use of existing operating modes on the trains show that considerable energy savings could be achieved with potentially very small investments or changes to the trains. The results generally show the importance of a continued investigation of the auxiliary equipment's energy use, as well as how the different operational situations other than the train service affect the total energy use. / Detta examensarbete utreder och analyserar energianvändningen för passagerarjärnvägsfordons traktion- och hjälpkraftssystem, både under tågdriften med passagerare och andra delmoment som tågen genomgår under den normala dagliga driften. För detta introduceras driftcykeln och tillhörande driftsituationer som ett sätt att beskriva användningen av ett tåg över tiden. Syftet är att beskriva de vanligast förekommande aktiviteterna och situationerna, såsom uppställning och parkering, regelbundna inspektioner, klargörningar och underhåll. Även hur dessa situationer påverkar energianvändningen genom ett varierande behov av hjälpkraft och aktiva funktioner i tågen. En energimodell baserad på driftcykeln som huvudsaklig indata, tillsammans med tågets egenskaper samt det omgivande klimatet, tas fram. Klimatet visar sig vara en avgörande faktor i hjälpkraftens energianvändning. Modellen utvärderas i typstudier på SJs X55 och Västtrafiks X61. Båda är elektriska motorvagnståg utrustade med energimätare. Indata till modellen samlas in genom tillgänglig teknisk dokumentation, tidigare studier och genom mätningar samt parameterestimering. Driftcyklerna för tågtyperna sammanställs med hjälp av olika planeringssystem och omloppsplaner. Väder- och klimatdata samlas slutligen in från öppna databaser för metrologiska data. Resultaten från typstudierna visar att metoden och modellerna är användbara verktyg för att kunna beskriva tågens energianvändning i deras driftcykler. Med möjligheten att särskilja hjälpkraftssystemens energianvändning vid tågdriften med passagerare men även i de övriga situationerna. Med detta blir det också möjligt att undersöka potentiella energibesparingsåtgärder för hjälpkraftssystemen. Simulering av förbättrade styrfunktioner för ventilationen och förbättrat utnyttjade av redan inbygga energibesparande driftlägen på tågen visar att betydande energibesparingar kan fås med relativt små medel och få förändringar på fordonen. De sammantagna resultaten av arbetet visar på vikten av att fortsätta undersöka och utreda hjälpkraftens energianvändning samt hur driftsituationerna utanför tågdriften med passagerare påverkar den totala energianvändningen.
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