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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.
1

Development of an integrated expansion evaporator and condenser unit for an advanced thermo-adsorptive battery system

Yu, Tao 09 October 2014 (has links)
The advanced thermo-adsorptive battery climate control system (ATB) is a highly innovative cooling and heating technology being developed by a cross-disciplinary academic and industrial team. The primary goal of this technology is to be employed in electric vehicles (EVs). In comparison with the conventional vapor-compression cooling system and the inefficient resistive heating method employed by the EVs’ industry, the ATB system is expected to offer EVs an additional 30% driving range by providing high cooling (2.5kWh) and heating (3.5kWh) storage in a lighter (<35kg) and more compact (<30L) system. The integrated expansion evaporator/condenser unit (IEECU) is one of the most crucial components comprising the ATB system. It combines the functions of an evaporator and a condenser and is designed to enhance the heat exchange between coolant and refrigerant. This thesis summarizes the work starting from the design, fabrication to characterizing process, with a particular focus on evaporation characterization. Development of ATB system and test setup including other components is covered in the rest of thesis. / text
2

DSP_Based Brushless Motor Driver for Electric Vehicle

Wu, Nan-Yi 26 July 2001 (has links)
This paper presented Symmetric and Asymmetric Regular Sampling techniques apply successfully to a Digital Signal Processor (DSP) together with an inverter. Experimental results are shown that taking advantage of SPWM control techniques can reduce the waste of energy. Further, the Soft Start techniques of DSP scripts can boost security for driver. Moreover motor driver safely can be increased by designing circuit to prevent over voltage. The function of motor driver will be better due to the decreased hardware size and increased accuracy which are the advantage of writing DSP scripts to analysis rotor speed.
3

The dynamic characterisation and modelling of lead-acid batteries for electric vehicle applications

Morgan, Clive January 1985 (has links)
In an effort to increase the available capacity of a lead-acid battery, the effects of pulsed discharge currents as opposed to the effects of continuous discharge currents on the battery were investigated, for a wide range of frequency, mark/space ratio and peak current of the discharge waveform. It was found that for certain conditions of pulsed discharge, the use of pulsed currents can provide a considerable increase in available capacity when compared to that obtained from using conventional continuous currents. In order to increase the efficiency and reduce the time of the lead-acid battery charge, the effects of using pulsed charging currents with ·and without depolarisation discharge pulses interspersed throughout the charging period as opposed to using conventional continuous current charging was investigated. For the tests performed, it was found that pulsed current charging without depolarisation pulses offers no advantages over conventional continuous current charging for three-stage and single-stage charging techniques. The use of pulsed currents with depolarisation pulses was found to be less effective than using conventional continuous current or straight pulsed current charging. A model for the cell terminal voltage and state-of-charge of the battery is derived from the results of an extensive series of tests performed by the author. In this writing for the first time a model accurately accounts for the dependence of recuperation, regeneration and wide variations in the discharge rate on the temperature of the electrolyte and the effects of these factors on the terminal voltage and state-of-charge. Additionally, for the first time a comprehensive model for use with pulsed discharge currents is derived. The models were tested under dynamic conditions of battery operation and were found to be able to predict battery state to a high degree of accuracy, and were also found to be more accurate than existing models.
4

Roaming Interoperability for Electric Vehicle Charging Networks

Al-Tubuly, Abdulnasir January 2016 (has links)
The purpose of this thesis is to analyze the maturity and the performance of the currently available roaming solutions that provide interoperability and roaming services to Electrical Vehicle Charging Networks. At least three different entities are involved in an Electrical Vehicle (EV) charging roaming scenario, namely the EV, the home charging network and the visited charging network. All of these entities have to interface and interact with each other on the physical and the communication protocols level. The Open Clearing House Protocol (OCHP) roaming protocol is implemented and its performance is evaluated against the e-Clearing.net test platform. The protocol functionality for billing and its suitability for different scenarios is also evaluated. Furthermore, an extension to the protocol is proposed to support prepaid subscription, and its performance is also estimated. The findings of this study have verified the performance and the maturity of the OCHP protocol, and strongly recommends the implementation of roaming protocols and clearing houses. The estimated performance of the proposed extension confirmed that both prepaid and postpaid billing can be realized using the tested roaming protocol and clearing house implementations.
5

Pack Level Design Optimization for Electric Vehicle Thermal Management Systems Minimizing Standard Deviation of Temperature Distribution

Bakker, Jeremy 30 October 2013 (has links)
Green technologies have recently gained interest for many reasons. Economic factors in conjunction with an increased social desire to reduce our environmental impact on the Earth have created a desire for more environmentally friendly technologies, especially automotive technologies such as the electric car. While public interest in electric vehicles is growing, there are a number of challenges which must first be addressed before their widespread adoption is possible. Cost, longevity, and range are all important factors which need to be addressed for electric vehicles to compete directly with their gasoline counterparts. By more efficiently using the energy stored within the battery pack, some of these issues can be addressed. This study focuses on the thermal management systems for electric vehicles and the application of design optimization in the early design phase considering the pack in its entirety. A liquid cooling system is considered for a current generation electric vehicle, with time dependent heat generation rates within the battery cells based on vehicle operating conditions. Identifying the most efficient distribution of cooling within the battery pack to achieve uniform temperature is the objective of optimization. Simulations were performed on a complete battery pack model, featuring 288 battery cells and 144 cooling plates. Anisotropic material properties and non-uniform heat generation rates are included as well as energy demands based on a representative vehicle drive cycle. Results have shown that through design optimization, the standard deviation of temperature within the battery cells can be improved by as much as 80% when compared to a conventional design. The standard deviation of temperature saw improvement from an average of 0.2828 K for a conventional design to 0.05318 K after optimization. These results are specific to the given battery pack construction, battery cell, and cooling type. The method of modeling and analysis can be extended to many battery geometries and cooling technologies in the future. Application of design optimization to the problem of thermal iii management system design can yield significant improvements to battery pack thermal management, and thereby incrementally improve the efficiency of electrified vehicles. / Thesis (Master, Mechanical and Materials Engineering) -- Queen's University, 2013-10-30 10:49:28.639
6

Interactions between industry emergence and policy adaptation : inspirations from China's regional electric vehicle (EV) industry development

Chang, Feifan January 2016 (has links)
No description available.
7

A Study on the Charging of Electric Vehicles On a Prototypical Residential Feeder

Taylor, David 31 January 2014 (has links)
Due to recent concerns regarding energy conservation and dependence on fossil fuels, the efficient integration of electric vehicle populations’ in the future smart grid has become a significant area of research. Despite the heavy penetration of smart meters throughout North America and Europe a lack of research exists utilizing real consumption data. Making use of smart meter data, a model of a prototypical residential feeder was created to observe the effects of increased electric vehicle penetration on the selected feeder. Simulations of the current operation of the feeder were performed along with modeled uncoordinated, coordinated, and coordinated vehicle to grid charging of electric vehicles. As expected, it was found that the normal operation of the feeder is subject to several inefficiencies which are made worse by uncoordinated charging of electric vehicles. Significant improvements in the considered operational parameters were found as a result of the coordinated charging of vehicles using a quadratic programming based control algorithm. Further it was found, that the use of coordinated vehicle to grid connections only produces marginal benefits over standard connections. Leading to the conclusion that development of charging controls is more significant to the mitigation of electric vehicle charging effects than the integration of vehicle to grid connections. / Thesis (Master, Physics, Engineering Physics and Astronomy) -- Queen's University, 2014-01-31 16:02:37.201
8

CAN Control System for an Electric Vehicle

Azzeh, Abdel Rahman January 2007 (has links)
The University of Canterbury has purchased a 1992 Toyota MR2 and used it as the platform to construct a new electric car. Similar to the common combustion engine vehicle, electric vehicles require control systems to control the operation of 12Vdc auxiliary loads, such as lights, indicators and windscreen wipers, where traditional technology results in a large number of wires in the wiring harness. Also, with the added complexity of modern vehicles, the need for integrating independent control systems together has become very important in providing safer and more efficient vehicles. To reduce the number of wires and make it possible for different control systems to communicate, and so perform more complex tasks, a flexible and reliable control system is used. The CAN (Controller Area Network) control system is a simple two-wire differential serial bus system, which was developed by Bosch for automotive applications in the early 1980s. The power and control system within the vehicle is named the "Power Distribution Network" and it is implemented by using multiple power converters and the CAN control system. This thesis presents the design, implementation, and test results of the CAN control system for the MR2. The 312Vdc nominal battery voltage is converted to an intermediate voltage of 48Vdc. This configuration is considered more efficient than the usual 12Vdc distribution system since smaller and lighter wires can be used to carry the same amount of power. The power distribution network operates off the 48Vdc intermediate voltage, and provides 12Vdc output to power all auxiliaries within the vehicle. The Power Distribution Network is implemented with two major subsystems: the auxiliary power system, which consists of multiple converters to step-down voltage from the 48Vdc intermediate voltage to the 12Vdc, and the CAN control system, which is developed to control and integrate the 12Vdc auxiliary loads within the vehicle. The prototype CAN control system is fully operational and has been tested with 12Vdc loads which are used to simulate most of the auxiliary loads in the vehicle. Experimental measurements show that the prototype is able to successfully control and maintain the network of independent nodes. This confirms that in principle the CAN control system is suitable for controlling the auxiliary loads in an electric vehicle.
9

Design, simulation, and construction of a series hybrid electric vehicle

Northcott, Daniel Ross 27 September 2007 (has links)
This thesis evaluates a series hybrid electric drivetrain design for use in parking patrol vehicles. Due to the particular attributes of this application, it is proposed that the design would improve the energy efficiency of such a vehicle. The scheme is evaluated in depth through the use of electromagnetic transient simulation tools, which are used to create a highly accurate model of the vehicle. A prototype vehicle of the same design is built, and used to verify and improve the accuracy of the simulation model. The simulation model is then used to predict the energy efficiency of the series hybrid design for parking patrol. This simulation based design strategy is proposed as a method for more rapid and cost effective design of hybrid electric vehicles. / October 2007
10

Design, simulation, and construction of a series hybrid electric vehicle

Northcott, Daniel Ross 27 September 2007 (has links)
This thesis evaluates a series hybrid electric drivetrain design for use in parking patrol vehicles. Due to the particular attributes of this application, it is proposed that the design would improve the energy efficiency of such a vehicle. The scheme is evaluated in depth through the use of electromagnetic transient simulation tools, which are used to create a highly accurate model of the vehicle. A prototype vehicle of the same design is built, and used to verify and improve the accuracy of the simulation model. The simulation model is then used to predict the energy efficiency of the series hybrid design for parking patrol. This simulation based design strategy is proposed as a method for more rapid and cost effective design of hybrid electric vehicles.

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