Daily Archives: 17 December 2015

Information and Communication Technology in Urban Electric Transportation

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Abstract

This paper is a first attempt at assessing the impact of information and communication technology in transport, with an accent on electric public transportation. Information
and communication technology is present in all spheres of human activity. Transport systems are made of vehicles and infrastructure. Modern vehicles are filled with complex
technology, such as electric drives, mechatronics, artificialintelligence and information and communication technology. And the infrastructure currently numbers only the roads and traffic lights, but the evolution of things leads to Intelligent Transport System. A technology that would connect vehicles and infrastructure to make transportation on land safer and more efficient. Electric vehicles require special attention to motor control. Power converters driven by intelligent modules allow an efficient control of the motor. A series of electronic systems for trolleybus and tram control, the SDMC, were made in Chiinău by the Informbusiness Company. The SDMC systems are intelligent system, built on microprocessors and CAN communication protocol. Modern ICT technology allows
simultaneously to ensures diagnostics, monitoring and protection of all components; to store the current state of the elements; to provide information means for the driver and
passengers and ensure good function of complex control algorithms. Information technology is present also in intelligent transportation systems with smart or even driverless vehicles. Technologies such as GPS and Wireless Networking allow optimizing urban transport, and are basic stones in the future of transport, which includes Intelligent Transport Systems and Driverless vehicles.		 images

Transversal Shape Optimization of a Brushless DC Motor for Electric Vehicles

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Abstract

The opportunity of this research is to emphasize certain approaches related to the design and modeling of low and medium power permanent magnet brushless DC motors for electric vehicles, which are presently poorly treated. The challenge of any manufacturer is to develop electric machines with minimum manufacture and maintenance costs by accomplishing the performance required by the customer. One looks for mathematical models as exact as possible as tools for the design and parameter computation. As a consequence of the progress of control and power electronics, the performances of brushless DC motors have been improved. Therefore, the problems of optimal design
and optimal operating mode of such motors are currently reported by the technical literature. By exploiting the available numerical computation tools, we developed the optimized technical design of a brushless DC motor for an electric bicycle. The performed simulations emphasize the technical performances which accomplish the customer requirements as follows: manufacture cost reduction of 27.9%, total cost reduction of 9.11% and a slightly growth of the maintenance cost of 8.01%. It is advisable to do a
periodical optimal re-design, which will take into account new performant electrotechnical materials with adequate technologies, in order to decrease the fabrication cost and to increase the energy efficiency of brushless direct current motors. The optimized motor achieves the required overallsize.		 images

Factors Involved in Choosing LEDs for General Lighting Applications: a Critical Review

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Abstract 

 

Electric lighting accounts for 19% of electricity consumption worldwide and generates remarkable concern to get energy savings. As a modern source of light, LEDs open up a multitude of innovative lighting solutions. LEDs lighting is already widely used in many niche areas like traffic lights, car lights, lighting displays, TVs etc. Now, based on lowered manufacturing costs, they penetrate into the general lighting market. But for specialists, LEDs are not yet the end solution in any lighting application. There are a lot of factors that can influence their adoption decision.Among them, the most favorable and promising one is the high efficiency, with values in permanent increasing. The paper discusses various aspects of LEDs efficiency and demonstrates that luminous efficiency is not a relevant criteria for a decision, a better understanding being got with an indicator like the Lighting Power Density, in W/m2. And beyond the efficiency, the paper makes a critical analysis of other parameters that matters in the lighting decisionmaking
process, like lifetime, color rendering and chromatic shift, health and environmental impact. Finally, the paper point out that the calculation of cost and return of investment
represent a very technical effort, based on accuracy of the entry data, often unknown by the investor itself, like different confidential costs, daily average time of functioning,
temperature hazards and lifetime in condition of poor quality of electricity.		 images