A. Mariscotti
GENERATING HIGH FIELD INTENSITY FOR VEHICLES IMMUNITY TESTS IN THE HF-VHF RANGE

In this work the problem is presented of generating an electric field in the HF and VHF range (few MHz to a hundred MHz) for immunity tests requiring high field intensity over a large volume of space. The spiral antenna architecture is discussed with respect to a series of parameters that are inter-related and influence field uniformity, beamwidth and overall gain (to be considered in terms of required rated power of the feeding amplifier). Reference is made to selected bibliography, that is not so abundant for our problem, the large part being for GHz range integrated applications. Some design choices have been evaluated by means of simulations, underlying that the tested simulators not always give accurate results: physical size, wire gauge and reflective ground plane effect, among others. The first measurement results match closely simulation results up to 90 MHz, where there is a large discrepancy and then simulation results seem inaccurate and not trustable.

Antonio Cataliotti, Valentina Cosentino
A SINGLE-POINT STRATEGY BASED ON IEEE 1459-2000 FOR THE DETECTION OF DOMINANT HARMONIC SOURCES IN POWER SYSTEMS

This paper deals with a new single-point strategy for the detection of harmonic sources in power systems. It is based on the simultaneous measurement of three nonactive power quantities, which are derived from the approach of the IEEE Std. 1459-2000. The proposed method is an enhancement of a previous approach, already developed by the authors. The new strategy is easier to be implemented than the previous one, because it is based only on the separation of the fundamental components from the harmonic content of voltage and current. As regard this, the strategy can be entirely implemented in the time domain, by using a technique already developed by authors for the detection of fundamental and harmonic components of voltages and currents. In the paper, some simulation tests are presented, which were carried out on a IEEE standard test power system. The simulation results show that the proposed method can give useful indications for the detection of the dominant harmonic source, upstream of downstream the metering section both in the absence and in the presence of the measurement transducers.

Antonio Cataliotti, Valentina Cosentino, Alessandro Lipari, Salvatore Nuccio
CHARACTERIZATION OF MULTIFUNCTION METERS BASED ON INTEGRATED DEVICES IN THE PRESENCE OF HARMONIC DISTORTION

This paper is focused on the problem of the metrological characterization of multifunction static meters based on integrated devices, in both reference and actual operating conditions. An experimental analysis is presented, which was performed on a commercial integrated device, in both sinusoidal and distorted conditions and both in the absence and in the presence of the measurement transducers. The experimental results show that the behaviour of the meters can be strongly influenced by the harmonics on voltage and current, depending on the operating principle of the meters, which is not always declared by the manufacturer. As regard this, the standards should define the metrological characteristics of the meters in the presence of harmonic distortion, as well as some proper accuracy tests for their verification. Moreover, the performance of the meters are strongly related to the employed voltage and current transducers, whose behaviour can be negatively affected by the presence of nonsinusoidal signals, because of their characteristics of frequency response.

Marian Jerzy Korczynski, Zygmunt Lech Warsza
A NEW INSTRUMENT ENRICHED BY TYPE A UNCERTAINTY EVALUATION

An idea of the new type of instrument, improved by pre-processing of the measurement data is presented in the paper. This instrument has an extensive data handling procedures, which allow to investigate different periodical and nonperiodical components in raw data and to clean the data from identified influences. Such cleaning upgrades the type A uncertainty evaluation. The developed instrument would be especially useful in technical diagnostic systems and medical testing instruments as well as in control systems in which different parameters are subjected to variation induced by internal or external influence. All theses application require not only to measure the value of a signal but also uncertainties. The measurement parameters in diagnostics and medical tests are very often subjected to environmentally caused disturbances in measurement. Measurements may be performed in highly interfering environment and useful signal may be lower than induced disturbances. In such situations the filtering of signals is required and handling of raw data is an appropriate procedure.

Pasquale Arpaia, Fabrizio Clemente, Carlo Manna
IN VIVO ASSESSMENT OF SKIN IMPEDANCE RECOVERY AFTER LOW-VOLTAGE PULSES ELECTROPORATION

The aim of this work is to measure the skin impedance recovery after electroporation by using low-voltage pulse protocol on human subject. Before and after electroporation, based on square wave pulses of 20-50 V, 5 μs, for 15-20 minutes, Electrical Impedance Spectroscopy (EIS) measurements has been performed, in the frequency range 0.5-10 kHz. Preliminary experimental results show a significant decrease in skin impedance amplitude after treatment. This result turns out to be useful in a measurement procedure aimed at determining the amount of drug actually transferred in electroporation-based therapy.