Search results for "Automotive"
showing 10 items of 619 documents
Influence of material properties variability on springback and thinning in sheet stamping processes: a stochastic analysis
2010
A very critical issue for stamping operations is the improvement of process robustness. The reliability of final results, in fact, strongly depends on the intrinsic variability due to stochastic behavior of many parameters, namely, operative ones and material properties. A given process performance may undergo a variation around the value which would be obtained neglecting stochastic behaviors of the operative or material parameters (i.e., considering a deterministic parameters behavior). Such variation introduces a significant source of uncertainty within the process design: a possible consequence may be the rejection of some stamped parts. In this paper, reliability analyses aimed to evid…
Techno-economic optimum sizing of hybrid renewable energy system
2013
Using off grid hybrid renewable energy systems for rural electrification has become an attractive solution for those areas, where grid electricity is not feasible or cost of the grid extension is relatively large. Hybrid system combines several energy systems together, therefore it can supply high reliable electricity rather than a PV/battery system or a wind/battery system. But the most important thing is that the system should be economically attractive. To achieve both of these features, each of the components in the hybrid system should be optimally sized. This requires a detailed techno-economic analysis of different possible hybrid system configurations. The objective of this study is…
Sustainable Transportation Management System for a Fleet of Electric Vehicles
2015
In the last few years, significant efforts have been devoted to developing intelligent and sustainable transportation to address pollution problems and fuel shortages. Transportation agencies in various countries, along with several standardization organizations, have proposed different types of energy sources (such as hydrogen, biodiesel, electric, and hybrid technologies) as alternatives to fossil fuel to achieve a more ecofriendly and sustainable environment. However, to achieve this goal, there are significant challenges that still need to be addressed. We present a survey on sustainable transportation systems that aim to reduce pollution and greenhouse gas emissions. We describe the ar…
A robust calibration methodology for an On-Board Diagnostic car system
2006
New car models are now by law equipped with on-board diagnostic (OBD) systems aimed at monitoring the state of health of strategic components that ensure low levels of polluting exhaust emissions. During development phases, for each new car model, the OBD system must be finely calibrated. This article presents a robust calibration methodology taking into account sources of variability mainly due to production process, operating, and environmental conditions. The methodology enables us to evaluate the false alarm and failure to detect risks intrinsically related to the adopted calibration. An application concerning an upstream oxygen sensor monitored by the OBD is presented.
Experimental study of the evolution of a bar breakage process in a commercial induction machine
2008
This paper analyzes the results of a destructive test developed on a commercial induction motor. The test is designed to reproduce in the laboratory the cage degradation process of an induction motor subjected to a high amount of working cycles, which include heavy startups. During each cycle, the main magnitudes related to the motor condition monitoring are registered, at steady state as well as at transient regime. From these magnitudes, some fault indicators described in the literature are calculated, and so, it is possible to follow their evolution. This analysis assesses the use of such small commercial machines in a test bed as a way of developing a failure that can be used to compare…
Piezoelectric Rainfall Energy Harvester Performance by an Advanced Arduino-Based Measuring System
2018
This paper presents the performances of rainfall energy harvesting through the use of a piezoelectric transducer and an Arduino-based measuring system. Different studies agree on the possibility of generating electricity from rainfall, but to date, a study on measuring the quantity of energy produced during rainfall is still missing. The present study begins with results obtained from laboratory researchers using piezoelectric transducers and oscilloscopes, finalized to measure the energy produced from a single raindrop, and concludes with an ad hoc Arduino-based measuring system, aimed to measure the actual amount of electrical energy produced by a piezoelectric transducer that is exposed …
Design issues for wind farms grid tied Inverter
2017
In this paper the Authors give indications for the design of a grid tied Voltage Source Inverters (VSI) aimed to optimal use in energy conversion from wind source. In particular, the design of the inverter is more focused on the control system planning, with a particular glance on the grid synchronization problem. After the exposition of general issues concerning renewable energies and associated topics, the case of a grid tied inverter is considered and a methodology of design is sketched starting from the consideration of the DC side and also considering the power device losses, the protection issue against over voltages and over-currents, snubber circuits, heat sinks and, finally the con…
Experimental characterization of a wind generator prototype for sustainable small wind farms
2016
This paper presents the experimental characterization of a wind turbine prototype used for micro wind farms. The proposed prototype, whose advantages can be summarized in versatility of application, low noise and compactness, can generate 1 kW of rated power for a wind speed equal to 4 m/s. The tests here reported and carried out by means of an experimental test bench confirm that the prototype is well designed and adequate for the purpose of its application.
Test Bench Realization and Application of Specific Working Cycles for the Characterization of Wheelchair Electrical Drives
2006
The life quality of motion disabled people is increased by the use of more and more sophisticated electrical wheelchairs. Despite the diffusion of such aid tools, specific technical standards for the determination of characteristic parameters of their electric drives are not so developed as the ones available for urban electric vehicles. In this paper, in order to define new technical standards for wheelchairs electrical drives, a wheelchair test bench has been purposely carried out. Moreover two specific working cycles, previously conceived and defined by some of the Authors to characterize the performances of the propulsion systems suitable for electrical wheelchair applications, have bee…
Static meters for the reactive energy in the presence of harmonics: an experimental metrological characterization
2009
Electricity metering plays a crucial role for all the commercial transactions on the energy market. Thus, an accurate evaluation of the performance of the electricity metering equipment is required not only in the reference operating conditions but also in the presence of disturbances affecting the power systems. As regards this matter, this paper analyzes the main aspects related to the metrological characterization of the static meters for the reactive energy in the presence of harmonic distortion. Attention is focused not only to the meters covered by the current standards but also to the meters of better accuracy and to the reference standard meters. The analysis is supported by several…