Search results for "Reliability engineering"
showing 10 items of 224 documents
A review of health assessment techniques for distribution transformers in smart distribution grids
2020
Due to the large number of distribution transformers in the distribution grid, the status of distribution transformers plays an important role in ensuring the safe and reliable operation of the these grids. To evaluate the distribution transformer health, many assessment techniques have been studied and developed. These tools will support the transformer operators in predicting the status of the distribution transformer and responding effectively. This paper will review the literature in the area, analyze the latest techniques as well as highlight the advantages and disadvantages of current methodologies.
Measurements methodology for the reliability evaluation of intelligent power modules
2014
The paper describes a measurement methodology for the reliability evaluation of new intelligent power electronics modules (IPMs). In particular, the evaluation of the IPMs immunity to radio frequency conducted disturbances has been performed, at different operating thermal conditions, designing a suitable measurement set up in a shielded room. Moreover, the thermal performances of the devices have been analyzed, setting up a proper experimental test bench. The measurements procedures are detailed described. © 2014 IEEE.
Practical procedure for verification of compliance of digital mobile radio base stations to limitations of exposure of the general public to electrom…
2002
In the last few years, society has witnessed the installation of an ever increasing number of radio base stations as a necessity for handling new capabilities and services to the large number of users. This rapid development of wireless networks, however, has induced a marked mistrustful attitude in people, who fear possible biological effects of electromagnetic emissions from mobile communications base stations. While there are guidelines on the limitation of human exposure to electromagnetic fields (emf ), there is no harmonised standard measurement procedure to evaluate compliance with the limits on exposure in the vicinity of a base station. The measurement procedure has to be practical…
On benchmarking the dependability of automotive engine control applications
2004
The pervasive use of ECUs (electronic control units) in automotive systems motivates the interest of the community in methodologies for quantifying their dependability in a reproducible and cost-effective way. Although the core of modern vehicle engines is managed by the control software embedded in engine ECUs, no practical approach has been proposed so far to characterise the impact of faults on the behaviour of this software. This paper proposes a dependability benchmark for engine control applications. The essential features of such type of applications are first captured in a general model, which is then exploited in order to specify a standard procedure to assess dependability measure…
Analysis of operator human errors in hydrogen refuelling stations: Comparison between human rate assessment techniques
2013
Abstract The use of hydrogen as an energy carrier for road transport appears to be an optimal solution for the reduction of greenhouse gas emissions. Nevertheless, the development of this technology depends on the growth and diffusion of production, storage and refuelling infrastructures together with accurate risk analyses to appropriately design the safety and management systems used in these plants. Moreover, to improve safety standards, it is also important to focus attention on the estimation of hazards related to human factors, as this is one of the major causes leading to accidental events, especially in complex industrial technology. The paper reports a case study relevant to operat…
Domestic load forecasting using neural network and its use for missing data analysis
2015
Domestic demand prediction is very important for home energy management system and also for peak reduction in power system network. In this work, active and reactive power consumption prediction model is developed and analysed for a typical Southern Norwegian house for hourly power (active and reactive) consumptions and time information as inputs. In the proposed model, a neural network is adopted as a main technique and historical domestic load data of around 2 years are used as input. The available data has some measurement errors and missing segments. Before using the data for training purpose, missing and inaccurate data are considered and then it is used for testing the model. It is ob…
A set of indices to assess the real performance of daylight-linked control systems
2017
Abstract The installation of Building Automation Control Systems (BACs) in general is an effective action to achieve relevant energy savings. Commercial BACs, installed in residential or small offices, often include functions of lighting control, acting as Daylight-Linked Control Systems (DLCSs). Nevertheless, because system performance is strictly dependent on different parameters, BAC’s hardware and software configuration and as well as an inaccurate commissioning do not always allow a perfect execution of the desired tasks; therefore, the system could not work as expected. Moreover, it is well known that energy saving potential is specifically related to the variability of the light envi…
Quality Assurance and Support Measures for Solar Cooling on System Level
2016
Abstract Within the IEA SHC Task 48 “Quality assurance and support measures for Solar Cooling” the analysis and evaluation of the systems has been one of the four main focuses. Here the activities are including the lab- and field-based characterization of the systems, the definition and application of performance figures, a guideline for a reliable monitoring procedure including methods for automated error detection and an updated overview on worldwide installed DEC systems including hints and good practice examples. They are furthermore leading to three different easy-to-use tools for solar cooling systems: The LCA tool considers environmental and energetic values for the evaluation, the P…
ELECTRE TRI-based approach to the failure modes classification on the basis of risk parameters: An alternative to the risk priority number
2017
Proposing an ELECTRE TRI-based approach for the failure modes classification into predefined and ordered risk classes.Direct identification of failure modes on which performing the corrective actions with priority.Easy definition of risk classes on the basis of DMs expertise and perception of the industrial context considered.Application to dairy manufacturing processes. Failure Mode and Effects Analysis (FMEA) is an engineering technique aimed at the detection of potential failures, their causes and consequences on the system/process under investigation. When used for the failure modes prioritization, FMEA is also referred to as Failure Mode, Effects and Criticality Analysis (FMECA). In tr…
Frequency stability in microgrid: control strategies and analysis of BESS aging effects
2016
In order to ensure a thorough analysis, all components placed in a microgrid would have to be considered to guarantee an effective energy management. To this aim, various algorithms are used both to preserve and restore power systems after significant disturbances. However, these models frequently do not evaluate components performance decline with the age and, consequently, they don't consider actual values during microgrid analysis, potentially affecting obtained results. In particular, evaluating energy storage systems aging and their effects has rarely been addressed in prior works. The present article proposes a model to maintain power system/microgrid stability after disturbances usin…