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The performance of Hall effect current transducers (HECT), under distorted waveform conditions, are usually characterized by means of the frequency response test. In this paper it was investigated if the frequency response is able to correctly evaluate the ratio and the phase errors under distorted conditions. A set of experimental measurements were carried out by comparing the frequency response...
Designing, optimizing and producing modern power amplifiers (PA) requires new and fast RF (radio frequency) measurement techniques capable of characterizing its real behavior. PAs are a truly multidimensional device where many desired performance parameters are contradictory to each other. This is especially true for the generation of modern communication PAs that require high efficiency, high linearity...
An electronic system based on a microcontroller architecture devoted to interfacing an Ultra Low Power (ULP) Metal OXide (MOX) gas sensor is presented. The circuit controls the operating temperature and manages the acquired data. A Pulse Width Modulation (PWM) signal with variable duty cycle is used to provide power to the heating resistor in order to set the desired operating temperature. The heating...
Redundancy is a common approach for ensuring reliability on applications using UPS inverters. However, overall system's reliability and efficiency is very dependent on the power measurement precision, which if not properly done can lead to system failure. Current transformers, that are widely used to measure the output current of UPS inverters, introduce a phase shift in the output signal that negatively...
The need for calibration of large electromagnetic flowmeters(EMF) adds considerably to the cost of these instruments. In order to reduce the cost, this paper discusses a technique for calibration of large electromagnetic flowmeters. The proposed technique based on unit element, moving unit flowrate set to measure the electromotive force of every point in the tube, and adds the weighting function arithmetic...
In a liberalized electric market the knowledge of the system status along with uncertainty affecting the estimated data is required to operate management and control issues, such as energy dispatching and protection coordination. The authors have recently proposed a novel procedure for harmonic source estimation aimed at giving distribution network operators information about the possible presence...
We present the results of an analytical study aimed at characterizing the mutual inductance M of Rogowski coils for generic paths of the primary wire and for nonuniform windings. In order to obtain such data, we performed a series of calculations based on the method of the mutual partial inductances and on the application of the Biot-Savart-Laplace law. Finally, we discuss the role of some critical...
A high-accuracy system for calibration of Rogowski coils at frequencies up to 10 kHz, based on a reference current transformer, an I/V converter, and a digital sampling system, is described in the paper. The calibration system has been automated and its performance evaluated. At the frequency of 10 kHz, the calibration system is capable of generating currents up to 100 A. At power frequencies, it...
Main cause for bearing failure are the common mode circulating currents. Those currents appear due to the use of inverters to drive electric motors. This paper presents a new method for fault detection by measuring common-mode currents. It is also presented the development of an electronic device which allows fault detection. The development has been tested in a test bench showing promising results...
The experimental characterization of free running, small (5-20 cm length, 0.5-1 cm radius) electron bunches in the keV energy range has a great importance for free electron laser (FEL) development. A fast electrostatic diagnostic on a pulsed beam produced with a photocathode source has been developed in the Penning-Malmberg trap ELTRAP, in which electron bunches move along the axis of the trap, from...
One solution for increasing the use of renewables is to find new strategies to allow distributed energy resources (DER) connection with the existing power system. A solution which allows a flexible integration of dispersed generation (DG) into energy networks is the use of DC at the user layer. One reason for choosing nowadays the DC technology for electrical energy distribution is the trend in the...
This paper presents a new microprocessor controlled communication interface device used in the electronic testing of mobile phone products in manufacturing environment. The main function of the device is to provide communication between the host computer and the device-under-test (by sending sequence of test signals and receiving test responses) as well as to control test fixture operation. The experimental...
The introduction of the European Directive on Measuring Instruments (MID), on 2004, has revolutionized the issue of the calibration and the traceability of the electrical energy meters. The MID imposes to calibrate the active energy meters accounting for real electromagnetic environments with peculiar disturbances. In many countries of the European Union, this factor has opened important economic...
This paper deals with the development of a complex measurement system for the online control of a laboratory scale DC grid located at "Politehnica" University of Bucharest. This has been achieved by making use of various communication methods among different modules, like DC source, energy meters, server, controllable "load computers", digital oscilloscope and multimeter. PHP and...
This study deals with the power electronics packaging and the needs for additional knowledge about electrical pressed contact behavior. For this, a measure bench has been realized. It is able to characterize the pressed interface between a metal electrode and a power chip as a function of the clamping force (0-8000N) and the temperature (up to 100degC). First measurement results show that the electrical...
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