This paper describes an original method based on the Fourier transform, developed in order to determine the characteristics of a signal containing fluctuating harmonics. Problems arising from applying the Fourier transform to signals that contain an infinite number of components are mentioned, and the way to overcome them is explained. Some simulations have been performed to prove the efficiency of the method.
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
This paper describes a standard system at LNE to measure RMS value of distorted voltage waveforms by means of a sampling voltmeter. Thermal converters are used to trace this quantity to the SI units. Deviations within 15 µV/V are obtained whatever the total harmonic distortion of the waveforms.
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
Rastislav Malych, Ondrej Barczi, Peter Vrabček
This paper describes the design, realization and basic characterization of the high current measurement system based on Rogowski sensor using an electrooptical transfer of the measuring signal. We present the principal schemes of the system and results of linearity measurements at 50 Hz frequency. The system is aimed for the on-site measurements on the distribution grids.
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
Magnetic sensors serve not only for the measurement of the magnetic field, but also to measure position, speed, force, torque, electric current and other variables. Magnetic compass is still an important navigation tool in case that GPS signal is not accessible, such as underground or underwater. Advances were made thanks to new materials (e.g. nanocrystalline), new principles (e.g. GMR and SDT) and new design procedures and tools (e.g. FEM simulation packages).
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
The talk presents an overview on relevant climate observation needs. The main focus is on the role of remote sensing methods in the context of the United Nations Framework Convention on Climate Change (UNFCCC) Kyoto protocol. In particular, the metrological challenges of a reliable earth observation for climate change detection and verification are discussed.
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
This paper deals with the beginning and birth of the IMEKO Technical Committee 4 (TC4) on “Measurement of Electrical Quantities”. It is the first part of the history of this committee and it is also a significant part of my life. I hope the reader will learn not only of the sequence of dates, but also of the humanity and commitment of the founding members. I apologize if I forgot someone or some events. We can avoid misunderstandings if we consider this paper as a first step of a dynamic process involving all those who want to write their memories and details I left out, in an open web site.
Instrumentation for the Information and Communication Technology Era · TC4 · 2010 · Download
Leakage detection methods are used to reveal liquid leaks in pipelines for many applications, namely, waterworks, oil pipelines, industry heat exchangers, etc.. The configuration of pipeline is a key issue because it impacts on the effectiveness of the method to be used and, consequently, on the results to be counterchecked. This paper proposes an improvement of impedance method for zigzag pipeline by carrying out an experimental frequency analysis that has been compared with other methods based on frequency response. Hence, impedance method is generally used for simple pipeline...
Instrumentation for the Information and Communication Technology Era · TC19 · 2010 · Download
David Sarriá, Antonio Sánchez, Joaquín del Río, Erik Molino, Antoni Mànuel, Frederic Valls
A remote data measurement and acquisition system has been developed to study the energy consumption of fishing trawler vessels, with the purpose to improve their efficiency. The system consists on a sensor network distributed along the vessel to monitor fuel consumption, navigation and fishing parameters. The data is acquired and stored by an embedded and robust system, which deals with the different protocols and interfaces of the sensors. The collected data is compressed and packaged in order to be sent via a GPRS modem to a land station, where data is analyzed and processed to study...
Instrumentation for the Information and Communication Technology Era · TC19 · 2010 · Download
A practical method with high accuracy in generation and application of error values for calibration of current transformer test sets is described. A PC-controlled three-phase power source with a standard wattmeter is used for generating the nominal and error test currents while an electronically compensated current comparator is used to provide summation and subtraction of them, precisely. With this method, any ratio error and phase displacement value could be generated automatically and nominal and test currents could be grounded on the test set safely. Because of its high accurate ratio...
Instrumentation for the Information and Communication Technology Era · TC19 · 2010 · Download
Fernando M. Janeiro, Frank Wagner, Pedro M. Ramos, A. M. Silva
Cloud height is an important parameter in both air safety and weather monitoring. The authors have previously developed a low-cost cloud height measurement system based on stereovision and digital photography. In this paper, the cloud height uncertainty is derived for the previously developed system. The main sources of uncertainty are identified and improvements to the measurement system are proposed.
Instrumentation for the Information and Communication Technology Era · TC19 · 2010 · Download