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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.
71

Automatizace výroby statorů elektromotorů / Automation of stators production

Šula, Martin January 2020 (has links)
The diploma thesis deals with the design of a robotic workplace layout for finishing operations on the stator of an electric motor. Three variants of the workplace layout were created, these variants were evaluated, and then the most suitable variant was selected. Suitable subcomponents have been created for this variant, such as the end effector, deburring spindles, rotary stand and milling table. A risk analysis was also created for her to ensure the safety and protection of the operator. The most suitable variant was transferred to the Process Simulate software, where its functionality was verified and the real cell cycle was determined.
72

Návrh dálničniho osobního vozidla na elektrický pohon / Design Study of Highway Electrical Passenger Car

Přikryl, Karel January 2011 (has links)
This thesis deals with design concept of the electric car. At first, vehicle dynamics was solved in program MathCad. The components were selected from the obtained results. This was followed by a proposal layout design and vehicles main dimensions design. The frame was created in program ProEngineer, and then imported into ANSYS. Simulation of torsional rigidity was made in ANSYS by FEM.
73

Návrh výkonové, řídicí a měřicí elektroniky elektrické brzdy s EC motorem / Design of power, control and measurement electronics for an electric brake with a BLDC motor

Drbohlav, Jan January 2013 (has links)
This paper describes the design of control, measurement and power electronics department for dynamic loading of electronically commutated motors with electric brakes. After comparing the advantages and disadvantages of possible conceptions the proposal focuses on electric brake operating in generator mode and the value of load is controlled by the current dissipated in a dummy load.
74

Návrh konstrukce vibrační třídičky odpadu / Design of vibrating waste sorter

Taska, Abraham January 2016 (has links)
The master thesis deals with a construction proposal for a vibrating sorter of cartridges. The thesis contains the theoretical part characterizing various sorter types of cartridges and describes the principle of sorting with the help of the vibrating sorters. The practical part includes a draft of a drive, calculation of a vibrating sorter, a proposal of compression springs bearing vibration frame and a control calculation of these springs. A complete vibrating sorter of the cartridges is created in a 3D modeling program. The thesis is attached by the drawings of the individual assemblies, subassemblies and individual parts.
75

Zařízení na výrobu vlákna z termoplastu PET pro použití k 3D tisku metodou FDM / An equipment for PET filament producing for 3D printing usage

Kotačka, Petr January 2016 (has links)
This thesis deals with design of equipment for the production of PET termoplastic fibre to be used in 3D printing by means of FDM method. Concise survey of plastics processing methods is presented herein, furthermore, structural design of equipment with necessary engineering calculations is included as well. Drawing documents with the total economic evaluation is a part of this thesis too.
76

Design and Performance Analysis of Rare-Earth-Free Five-Phase Permanent Magnet-Assisted Synchronous Reluctance Motor

Islam, Md. Zakirul January 2019 (has links)
No description available.
77

LabView-baserat produktionstest för borstlösa trefasiga likströmsmotorer / LabView-based production test for brushless three phase direct current motors

Thulin, Marlene January 2019 (has links)
Testning är en viktig del i tillverkningskedjan för att säkerställa kvalitet och funktion hos elektronikprodukter, och utförs ofta på flera nivåer innan den färdiga produkten lämnar fabriken. Produktionstester är rutinmässiga tester som tillämpas under masstillverkning och vid utformning av dessa måste tidseffektivitet prioriteras för att minimera negativ inverkan på produktionstakten. I detta projekt överfördes ett produktionstest för färdigmonterade borstlösa DC-motorer med drivelektronik till en ny testutrustning hos företaget Allied Motion. Testet skulle moderniseras och införas i företagets mjukvaruplattform uppbyggd i programspråket LabView. Testsekvensen kunde effektiviseras främst genom att kombinera dess delmoment och låta körningar av motorn användas för att testa flera egenskaper istället för att upprepas. Resultatet blev ett test som täckte in samma mätningar som i det äldre systemet med undantag för enstaka moment, samt mätte hastighet och momentkarakteristik med högre precision. Det omarbetade testet bestod av fyra deltester jämfört med tidigare tolv steg, och implementerades i fyra LabView-baserade testfall som kunde användas för att skapa en komplett testsekvens i plattformen. Uppgiften visade sig dock kräva mer tid och arbete än vad som uppskattats inledningsvis, och därför återstod flera av de arbetsuppgifter som planerats inom projektet att slutföra innan det nya testet skulle kunna tas i bruk i produktionen. / Testing is an important part of the manufacturing process to ensure the functional quality of electronics products, and is often performed in multiple stages during product assembly before the final product leaves the factory. Production tests are applied as a routine on all units in a production line, therefore time efficiency must be prioritized in the design of such tests in order to minimize the negative effect imposed on production rate. In this project an existing production test for fully assembled brushless DC motors was re-implemented for a new test equipment at Allied Motion. The purpose was to modernize the test and implement it in the company’s own LabView-based software platform. The test sequence was streamlined by combining and thereby reducing the number of steps, using the same motor runs to test multiple functions rather than repeating run sessions to collect data for similar test steps. The project resulted in a new test that, with a minor exception, covered the same measurements as in the old system and measured speed and torque performance with higher precision. The new test consisted of four partial tests instead of the earlier version’s twelve test steps, which were implemented in LabView-code as four separate test cases that could be used in creating complete test sequences in the software platform. The project task though turned out to require more time and effort than was initially estimated, and several parts that had been planned to be completed within the project time still remained before the test could be taken into use in the production line.
78

Study on a high precision drilling tool with focus on power source and driveline / Studie av en högprecisionsborrmaskin med fokus på kraftkälla och drivlina

Hallberg, Daniel, Ringdahl, Patrik January 2017 (has links)
This thesis was carried out at Atlas Copco Industrial Technique in Nacka, Sweden. Atlas Copco is a world leading manufacturer of industrial tools for a wide range of industries. One application is semi-automatic drilling machines for the aerospace industry. The latest trend for such tools is moving in a direction of increased control and traceability. The purpose of this thesis was to investigate the possibility of replacing the pneumatic motor in an industrial semi-automatic drilling machine, PFD1100, with an electric motor and explore the possibilities such design would enable. The two main priorities for the thesis have been:  Investigate the capacity of an electric motor developed by Atlas Copco and find out if it’s suitable for use in drilling applications.  Develop concepts for a new driveline, solving the two core functions of the drill - spindle rotation and spindle feed. The thesis has been limited to use the electric motor from an existing nutrunner and carry over the design for the spindle mechanism from the PFD1100 drilling machine. A background study was conducted of the aerospace industry in general and drilling applications in particular. The authors made a study visit to Airbus production facilities in Hamburg to get a better insight of where and how the tools are used. The background study supported the need for an electric drilling machine, targeted at smaller hole sizes and stack drilling applications. A hybrid prototype machine was designed and manufactured consisting of the driveline from the PFD1100 drilling machine and the motor and electrics from an electric nutrunner. The purpose of the prototype was to verify analytical calculations of the mechanical drilling power through physical testing, and investigate how the machines would behave with an electric motor. The prototype showed promising results with respect to drilling performance and basic adaptive drilling. The electric motor from the nutrunner was tested in a power test rig and the results were used to adapt an existing MATLAB script for estimating motor and inverter losses. With the adapted script provided by Atlas Copco, the gear ratio for the drilling machine could be optimized to minimize losses in the motor and electrical systems. Finally, concepts for a transmission between the electric motor and the spindle mechanism was generated and evaluated with a weighted Pugh’s evaluation matrix. Concepts focused on achieving a tool with minimum size and weight as well as expanding the tool functionality. The most promising concepts according to the evaluation were those that offered a compact and robust solution. To minimize resources and time to market, these concepts could offer a good starting point for continued develpoment. / Detta examensarbete utfördes vid Atlas Copco Industrial Technique i Nacka, Sverige. Atlas Copco är världsledande leverantör av industriella verktyg till olika typer av industrier, bland annat flygindustrin. Semi-automatiska borrmaskiner har använts inom flygindustrin i flera år och trenden för sådana verktyg rör sig i riktning mot ökad kontroll och spårbarhet. Syftet med arbetet var att undersöka möjligheten att ersätta den pneumatiska motorn i en industriell semi-automatisk borrmaskin, PFD1100, med en elektrisk motor samt utforska de fördelar som en sådan konstruktion kan medföra. De två huvudprioriteringarna var följande:  Undersöka kapaciteten hos en elmotor utvecklad av Atlas Copco och hur den lämpar sig för en borrmaskin.  Utveckla koncept för en ny drivlina som löser de två huvudfunktionerna rotation och matning av borrspindeln. Examensarbetet avgränsades till att använda motorn från en befintlig mutterdragare och grundprincipen från PFD1100 borrmaskinens mekanism för spindeldrivning. I en bakgrundsstudie undersöktes flygindustrin i allmänhet och borrningsapplikationer i synnerhet. Författarna gjorde ett studiebesök hos Airbus produktionsanläggning i Hamburg för att se hur verktygen används och vilka behov som finns. Från bakgrundsstudien drogs slutsatsen att en elektrisk maskin bör rikta in sig mot mindre hålstorlekar och tillämpningar av stackborrning. En prototyp konstruerades bestående av drivlina och spindeldrivning från PFD1100 och motorpaket och styrning från en elektrisk mutterdragare. Syftet med prototypen var att verifiera teoretiska beräkningar av den mekaniska borreffekten och få en ökad förståelse för maskinens beteende med en elmotor. Prototypen visade lovande resultat med avseende på borrning och kunde även utföra adaptiv borrning i viss utsträckning. Den elektriska motorn testades i en effektprovrigg och resultatet användes för att anpassa ett befintligt MATLAB-skript för beräkning av motorförluster. Skriptet, som tillhandahölls av Atlas Copco, användes för att optimera utväxlingen för verktyget i syfte att minimera effektförluster i motor och elektronik. Flertalet koncept genererades för rotation och matning där några av koncepten skulle ge ett så kompakt verktyg som möjligt med låg komplexitet, medan andra koncept fokuserade på utökad funktionalitet. Koncepten utvärderades med en viktad Pughs utvärderingsmatris. De mest lovande koncepten enligt konceptutvärderingen var de som erbjöd en kompakt och robust lösning som tillämpar kända tekniska principer. Om resurskrav och tid till marknad ska minimeras så kan dessa koncept utgöra en bas för fortsatt utveckling.
79

On The Mechanical Design of Power Dense Axial Flux Permanent Magnet Synchronous Motors for Aircraft Propulsion Applications

Duperly, Federico January 2024 (has links)
Traffic congestion in large urban and metropolitan areas is a substantial problem plaguing these areas. Not only are commuters losing valuable time, but greenhouse gas emissions are substantially worse because of congestion. Considerable research and development into next generation electrified aircraft is ongoing to introduce air mobility as a viable new means of transporting people and goods across long commutes. This development extends into commercial aviation as a whole as a means of reducing the industry’s carbon footprint with new aircraft designs that employ electrified propulsion systems. Many electrified aircraft projects are currently underway, ranging from small commuter aircraft all the way to large twin-aisle aircraft, and part of the development scope for alot of these projects is creating highly robust and power dense electric machines that replace the current state-of-the-art. The axial flux permanent magnet synchronous machine is an exciting candidate for aircraft propulsion due to its exceptional torque density and compact axial nature. In this thesis, the mechanical design for three generations of axial flux permanent magnet synchronous machines is discussed. These machines serve as development phase prototypes for machines that are ultimately intended for propulsion applications in commercial aviation, particularly for eVTOL aircraft. The motivation for electrification in the commercial aviation industry is discussed, followed by an overview of the development landscape for electrified propulsion systems in commercial aviation, focusing primarily on electric machines that are currently state-of-the-art or are set to be in the near future, as well as what is required for future electric machines in terms of power output and power density. The axial flux architecture is then presented, including a high-level comparison to the radial-flux architecture, an overview of the various axial flux machine designs and topologies, and a discussion of the inherent mechanical design challenges associated with the axial flux architecture. The yokeless and segmented armature axial flux permanent magnet synchronous machine design was selected for the machines developed as part of the research for this thesis, and the discussion of the mechanical design of these machines is broken up into the two core sub assemblies: stator assembly and rotating assembly. High-level design methodologies are introduced for both sub-assemblies, which is further broken down into different approaches pertaining to each generation. The first and second generation designs are presented at a high level, followed by deep-dives into the complete mechanical design for the third generation stator, the bearing selection, arrangement, and analysis for the third generation rotating assembly, and adhesive characterization trials used to guide adhesive selection for rotor magnetics retention in the second and third generation machines. The current status of the machines and any outcomes from testing that has been conducted thus far, particularly with respect to performance, is presented at the end. / Thesis / Master of Applied Science (MASc)
80

Electrification of rock drills : An initial study of an electromagnetic percussion concept

Smith Siljestrand, Jakob, Chebolu, Sai Shridhar January 2023 (has links)
The world is looking for greener solutions and so is the mining industry. This quest has led to the question whether it is possible to have a completely electric rock drill. This work carries out an initial exploration of completely electrified percussion. Furthermore, it compares the preliminary performance of an electrified rock drill against a hydraulic counterpart. A mathematical model for an electromagnetic linear motor was developed and simulated as a component in the simulation software Hopsan. This component was then incorporated into a electromagnetic rock drill model which uses components from Epiroc’s in-house developed library. The electromagnetic rock drill model was then optimised and used to obtain the performance characteristics such as impact energy and frequency which were compared against one of the hydraulic rock drill models, COP 1838. The results show that it is possible to reach the same performance as the COP 1838 with enough input current. The characteristics were then studied with respect to variation of physical parameters of the electromagnetic linear motor and input current. Finally some limitations and strengths of the electromagnetic rock drill concept are discussed and some conclusions are presented.

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