Traceable measurements of harmonic (2 to 150) kHz emissions in smart grids: uncertainty calculation

2020 ◽  
Vol 9 (2) ◽  
pp. 375-381
Author(s):  
Daniela Istrate ◽  
Deepak Amaripadath ◽  
Etienne Toutain ◽  
Robin Roche ◽  
Fei Gao

Abstract. The necessity of measuring harmonic emissions between 2 and 150 kHz is outlined by several standard committees and electrical utilities. This paper presents a measurement system and its traceable characterization designed to acquire and analyse voltages up to 230 V and currents up to 100 A with harmonics up to 150 kHz that may occur in smart grids. The uncertainty estimation is carried out and described in detail for both the fundamental and supraharmonics components. From a metrological point of view, ensuring the traceability of current measurements for frequencies higher than 100 kHz and dealing with the complexity of uncertainty determination are bottlenecks related to supraharmonics measurements that this paper proposes an approach to deal with.

2017 ◽  
Vol 17 ◽  
pp. 236-245
Author(s):  
V. V. Kozhevnikov

Today one of the priority problems is receiving an accreditation certificate under the international standard ISO/IEC 17025:2006 by measurement laboratories of Expert service subdivision of the Ministry of Internal Affairs of Ukraine. One of the requirements which is shown to the accredited testing laboratories, is a presence of uncertainty estimation procedure and ability to apply it. As the ballistic researches are one of the important directions of researches which are carried out in the expert subdivisions, therefore the paper is devoted to the consideration ofa question of uncertainty calculation in such measurements. In the mathematical statistics two types of paramètres which characterize dispersion of not correlated random variables are known: a root-mean-square deviation and a confidential interval. As the characteristics of uncertainty they are applied under the title standard and expanded uncertainty. An elementary estimation of measurements result and its uncertainty is carried out in such an order: description of the measured quantity; revealing of uncertainty sources; quantitative description uncertainty constituents (there are estimated uncertainty constituents which can be received a posteriori or a priori); calculation of standard uncertainty of each source, total standard uncertainty and expanded uncertainty. A posterior estimation is possible only in the case of carrying out multiple observations of the measured quantity (standard uncertainty of type A). An a priori estimation is carried out when multiple observations are not performed. In this case it’s necessary to use the information received from the measurements performed before, from the passport data on the facilities ofmeasuring technics orfrom reference books (standard uncertainty of type B). Short consideration of uncertainty concept, elucidation of the basic stages measurements result estimation and its uncertainty gives the chance to transform the theoretical knowledge into practical application of uncertainty estimation on examples of measurements uncertainty calculation during carrying out ballistic ammunition researches by two different ways.


Author(s):  
Ali Abedi ◽  
Kale Schrader

One of the major limiting factors preventing wide use of wireless sensor networks in practical scenarios is power consumption. Battery-less or passive sensors promise to alleviate this issue and enable a wide variety of embedded sensor applications such as structural health and vehicular monitoring, biomedical applications, smart homes, and smart grids. Embedding these sensors in structures without the need for changing batteries, their rugged design to withstand harsh environments, and coded communication with multiple access features makes this technology a desirable candidate for a variety of applications. Design and analysis of these sensors from a cross layer point of view is studied in this book chapter. State of the art in fabrication and test of this new class of wireless sensor systems is also reviewed. Interactions between lower layer with passive sensors and upper layer with active sensors—a different perspective on cross layer—is exploited to achieve significant performance gains in terms of signal to noise and interference ratio, correlation peak to side-lobe ratio, operation range, and data rate.


Energies ◽  
2018 ◽  
Vol 12 (1) ◽  
pp. 118 ◽  
Author(s):  
Vitor Monteiro ◽  
Jose Afonso ◽  
Joao Ferreira ◽  
Joao Afonso

Nowadays, concerns about climate change have contributed significantly to changing the paradigm in the urban transportation sector towards vehicle electrification, where purely electric or hybrid vehicles are increasingly a new reality, supported by all major automotive brands. Nevertheless, new challenges are imposed on the current electrical power grids in terms of a synergistic, progressive, dynamic and stable integration of electric mobility. Besides the traditional unidirectional charging, more and more, the adoption of a bidirectional interconnection is expected to be a reality. In addition, whenever the vehicle is plugged-in, the on-board power electronics can also be used for other purposes, such as in the event of a power failure, regardless if the vehicle is in charging mode or not. Other new opportunities, from the electrical grid point of view, are even more relevant in the context of off-board power electronics systems, which can be enhanced with new features as, for example, compensation of power quality problems or interface with renewable energy sources. In this sense, this paper aims to present, in a comprehensive way, the new challenges and opportunities that smart grids are facing, including the new technologies in the vehicle electrification, towards a sustainable future. A theoretical analysis is also presented and supported by experimental validation based on developed laboratory prototypes.


2012 ◽  
Vol 19 (3) ◽  
pp. 573-582 ◽  
Author(s):  
Ariel Dzwonkowski ◽  
Leon Swędrowski

Abstract The electrical power drawn by an induction motor is distorted in case of appearance of a certain type of failures. Under spectral analysis of the instantaneous power one obtains the components which are connected with definite types of damage. An analysis of the amplitudes and frequencies of the components allows to recognize the type of fault. The paper presents a metrological analysis of the measurement system used for diagnosis of induction motor bearings, based on the analysis of the instantaneous power. This system was implemented as a set of devices with dedicated software installed on a PC. A number of measurements for uncertainty estimation was carried out. The results of the measurements are presented in the paper. The results of the aforementioned analysis helped to determine the measurement uncertainty which can be expected during bearing diagnostic measurements, by the method relying on measurement and analysis of the instantaneous power of an induction machine.


Author(s):  
Pradeep Shinde ◽  
Cheng-Xian Lin

Uncertainty estimate, although an important subject, is not carried out in a consistent way by different researchers. In this paper, the authors performed a systematic analysis to enumerate the uncertainty calculation procedure for the brazed aluminum microchannel heat exchangers with louvered fins. Using the basic method suggested by Moffat (1988), the present study elaborates the uncertainty estimation of Reynolds number, Colburn j-factor, and friction f-factor for a liquid-air brazed aluminum heat exchanger system. The important factors and their calculation procedure associated with the uncertainty analysis are discussed. The procedure is verified and the uncertainties are estimated for a standard microchannel heat exchanger configuration available in the market. The effect of the measurement variables on the uncertainty factor is illustrated in figures. The range of uncertainties for Reynolds number, Colburn j-factor and friction f-factor are examined within the investigate parameter ranges. The study provides the calculation procedures and conditions as future reference for uncertainty analysis of louver fin brazed aluminum heat exchangers, in particular. The paper also discusses uncertainty estimation for heat exchanger systems, in general.


2022 ◽  
Vol 3 (1) ◽  
pp. 1-10
Author(s):  
Damian Bzinkowski ◽  
◽  
Tomasz Ryba ◽  
Zbigniew Siemiatkowski ◽  
Miroslaw Rucki ◽  
...  

The paper presents a novel system for monitoring of the work of industrial belt conveyor. It is based on the strain gauges placed directly on the roller surface that measure pressing force of the belt on the roller. Automatical operation of the measurement system minimizes impact of an operator on the measurement results. Experimental researches included the stability of indications during 5 days, Type A uncertainty estimation and equipment variation EV calculations. Expanded uncertainty calculated for the level of confidence 95% was below 0.1% of the actually measured value, and percentage repeatability %EV = 9.5% was obtained. It can be considered satisfactory, since usually it is required %EV < 10% for new measurement systems.


2021 ◽  
Vol 13 (18) ◽  
pp. 10369
Author(s):  
Gabrielle Biard ◽  
Georges Abdul Nour

Industry 4.0 has revolutionized paradigms by leading to major technological developments in several sectors, including the energy sector. Aging equipment fleets and changing demand are challenges facing electricity companies. Forced to limit resources, these organizations must question their method and the current model of asset management (AM). The objective of this article is to detail how industry 4.0 can improve the AM of electrical networks from a global point of view. To do so, the industry 4.0 tools will be presented, as well as a review of the literature on their application and benefits in this area. From the literature review conducted, we observe that once properly structured and managed, big data forms the basis for the implementation of advanced tools and technologies in electrical networks. The data generated by smart grids and data compiled for several years in electrical networks have the characteristics of big data. Therefore, it leaves room for a multitude of possibilities for comprehensive analysis and highly relevant information. Several tools and technologies, such as modeling, simulation as well as the use of algorithms and IoT, combined with big data analysis, leads to innovations that serve a common goal. They facilitate the control of reliability-related risks, maximize the performance of assets, and optimize the intervention frequency. Consequently, they minimize the use of resources by helping decision-making processes.


2020 ◽  
Author(s):  
Christoph Gerbig ◽  
Harald Franke ◽  
Ralf Stosius ◽  
Florian Obersteiner ◽  
Torsten Gehrlein ◽  
...  

&lt;p&gt;Within the framework of the research infrastructure IAGOS (In-service Aircraft for a Global Observing System), a cavity ring-down spectroscopy (CRDS)-based measurement system for the autonomous measurement of the greenhouse gases (GHGs) CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;2&lt;/sub&gt;, as well as CO and water vapour is deployed on a Lufthansa Airbus A330 since September 2018. This IAGOS-CORE system is equipped with a two-standard in-flight calibration system, allowing for trace gas measurements to be fully traceable to WMO calibration scales. Various lessons have been learned during the first deployment periods related to the autonomous operation of the system over periods of several months, enabling the future extension of the GHG measurements to aircraft from further airlines. Apart from the presentation of the observations, the presentation will discuss the data quality and uncertainty estimation.&lt;/p&gt;&lt;p&gt;A further CRDS system for autonomous measurement CO&lt;sub&gt;2&lt;/sub&gt; and CH&lt;sub&gt;4&lt;/sub&gt; is integrated within the instrumented IAGOS-CARIBIC container deployed on board an Airbus A340 on a bi-monthly schedule since July 2018. By now this system has provided data from more than 30 flights. Data will be presented, and the potential of the observations for research applications will be introduced. Also the availability of IAGOS GHG data to the research community will be discussed.&lt;/p&gt;


1993 ◽  
Vol 60 (1) ◽  
pp. 23-28 ◽  
Author(s):  
Maureen Wright ◽  
Elizabeth Scott ◽  
Rhonda Cockerill

Using a procedure-based occupational therapy workload measurement system developed at, and applied by, Sunnybrook Health Science Centre, this paper explores the objectives of such a system from the point of view of the occupational therapy manager. It also takes into account the synergistic relationship between the occupational therapist and the administrative/business aspect of health care, paying special attention to past and present trends in health-care accountability. In this paper it is argued that occupational therapy managers must relate their procedures and overhead costs to actual client care, if they are to be included in programme management and client costing. The process used by occupational therapy to describe its own procedures for the system is outlined. The system was then developed in conjunction with other institutional, financial and management tools for the client cost conversion process. By using a procedure based workload measurement system, occupational therapy is able to accurately describe client costing, thereby articulating our role in client care.


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