• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 1
  • 1
  • Tagged with
  • 2
  • 2
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 1
  • 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.
1

Carregador de Baterias MonofÃsico Para AplicaÃÃo em VeÃculos ElÃtricos / âSingle-Phase Battery Charger Feasible for Electric Vehicles Applicationsâ,

CÃsar Orellana Lafuente 28 June 2011 (has links)
Este trabalho apresenta o estudo de um carregador de baterias monofÃsico aplicado a veÃculos elÃtricos. Este carregador à composto por dois estÃgios de processamento de energia e um circuito digital de supervisÃo para controlar a tensÃo sobre o banco de baterias e a corrente de recarga das mesmas. O primeiro estÃgio consiste de um conversor CA-CC bridgeless com caracterÃstica de alto fator de potÃncia, e o segundo estÃgio à representado por um conversor CC-CC fullbridge com isolamento em alta frequÃncia e comutaÃÃo sob tensÃo nula (Zero Voltage Switching â ZVS). Para ambos os conversores, foi realizada uma anÃlise qualitativa e quantitativa, bem como apresentados exemplos de projeto para facilitar o dimensionamento dos componentes. Finalmente, com os componentes escolhidos, foi montado um protÃtipo que permite carregar de uma atà oito baterias de 12 V conectadas em sÃrie. O sistema apresenta como especificaÃÃes: tensÃo de entrada alternada de 220 VÂ15%; tensÃo de saÃda contÃnua de 120 V; corrente de saÃda contÃnua de 20 A; e potÃncia mÃdia de saÃda de 2,4 kW. / This work presents a single-phase battery charger for electric vehicles. This converter is composed by two energy processing stages and a digital circuit to control the voltage across the batteries and their respective charging current. The first stage is a high power factor ACDC bridgeless converter, while the second one consists on a ZVS (Zero Voltage Switching) high frequency isolated DC-DC full-bridge converter. For both converters, the qualitative and quantitative analyses have been performed, as well as design examples have been presented in order to ease the components calculation. Finally, a prototype that allows charging up to eight series-connected 12 V batteries has been built. The system specifications are: AC input voltage of 220 V Â15%; DC output voltage of 120 V; DC output current of 20 A; and average output power of 2.4 kW.
2

Development of a Bar Changer for a Punching Machine

Shafai, Zamen January 2020 (has links)
This master thesis was performed at the Mechanical department at Outotec AB,Skellefte˚a. Outotec AB is a technology company as well as a project company, sell-ing complex mining technology and plant projects. Outotec’s technologies are usedfor applications such as producing base metals, processing iron ore etc. Outotec isrunning a program called ‘Fully automated smelter’ where manual hazardous workmust be avoided. A machine which automatically replaces punching bars on thepunching machine is needed. This thesis project aimed to investigate if the punching bar changer will be aproprietary purpose-build machine or an industrial robot. The five-step conceptgeneration method was used for concept development during this thesis project.For gathering knowledge and information about the project area, experts have beeninterviewed to obtain information for the start of the project. The gathered infor-mation and knowledge from interviews and literature studies have been used as abase when the concepts were generated. Seven concepts were generated and evalu-ated using a screening matrix. The concept that best satisfied the set requirementswere further developed, designed and simulated. The two scenarios have been in-vestigated and a design concept of the proprietary purpose-built machine has beenpresented. The result from concept evaluation and simulation indicated that bothalternatives are applicable in this area. But to make a decision a more in-depthcalculation of the associated cost and investigation of the design is necessary.

Page generated in 0.0992 seconds