Ionel Pavel

Scopus Publications

Estimation of the Spatial and Temporal Distribution of Magnetic Fields around Overhead Power Lines—A Case Study
Ionel Pavel, Camelia Petrescu, Valeriu David, and Eduard Lunca
MDPI AG
Due to the growing number, diversity and spreading of magnetic field sources, an increasing need to determine the field levels of human exposure has arisen. Some of the most encountered sources are the overhead power lines (OPL) and the determination of spatial and temporal variation of the magnetic fields produced by OPLs is a challenge. In this paper a hybrid method for the estimation of the temporal and spatial distribution of the magnetic flux density B caused by OPLs, based on experimental measurements and on numerical and analytical simulations, is presented. Thus, using a small number of simultaneous spot measurements correlated with a long-term survey, maps of the magnetic flux density distribution on extended areas are established, for several time instances. The proposed method is verified using two sets of different measurements and the results obtained through simulation. The difference between the estimated and simulated values of B is under 5.5%, which is considered acceptable considering that B spans over a large set of values (724 nT ÷ 1375 nT) in the location of the long-term survey procedure. The possibilities and limitations of the proposed method are discussed.

Monitoring of Classical and Modern Education
Costel Donose, Cristina-Mihaela Schreiner, Ionel Pavel, and Madalina Ancuta Pintilei
IEEE
The material base within an educational process, be it classic or distance learning, contributes to the development of factors that stimulate learning, having principles defined according to the learning method chosen by students. An important role is played by teachers who must develop this material basis of learning according to principles adapted to all learners, especially in the case of online education, when teachers and students are separated. This last case grew with the advent of the COVID-19 pandemic period. Therefore, in our study we presented the two methods, classical and modern, which combined, could make it possible to teach in high schools or universities even during the pandemic. At the end of this study, an evaluation of the two methods was made and an improvement in students' results was found, increasing their interest in learning and at the same time reducing the costs of implementing laboratory works by using a small amount of equipment.

Measurement and Numerical Simulation of the Low-Frequency Electric Field Generated by an Overhead Power Line
Eduard Lunca, Silviu Vornicu, Ionel Pavel, and Mihai Andrusca
IEEE

Video Distance Measurement Method Based on the Weighted Average of the Depth Intervals Centers
Ionel Pavel, Codrin Donciu, Marinel Temneanu, and Mihai Penciuc
IEEE

Low frequency magnetic field survey in different areas of a hospital's environment
Ionel Pavel, Valeriu David, Marina-Georgiana Roman, and Alexandru-Marian Bordas
IEEE

LabVIEW Based Control and Monitoring of a Remote Test-Bench Experiment for Teaching Laboratories
Ionel Pavel, Marius Branzila, Constantin Sarmasanu, and Costel Donose
IEEE
Recently, great efforts have been made to passing from traditional to online learning due to the COVID-19 pandemic. Regarding online learning, many concepts have been developed to use various learning methods in electrical engineering laboratories because this involves equipment that students have not access. To solve this problem, virtual instruments have been made to control and monitoring equipment from the laboratories. In this paper, we presented a solution for the development of a remote laboratory for measuring a DC motor speed. The greatest advantages of this method are the remote interaction of the students with the workbenches in classes, the shortening working time, the measured values accuracy, the automatic graph drawing, and reducing measurement errors.

A Method for Estimating the Magnetic Fields Generated by the Overhead Power Lines
Valeriu David, Ionel Pavel, and Eduard Lunca
IEEE
In this paper we propose a new measurement method to estimate the spatial and temporal variability, namely to realize maps with magnetic induction B anywhere and anytime around overhead power line, using only two measurement instruments and a minimum number of measurements. Based on the obtained results of spot measurements and the results of an automatic survey of magnetic induction B, we estimate the profiles and the maps of magnetic fields anywhere near the line, i.e. spatial variability and anytime, i.e. temporal variability. These two sets of synchronous measurements where made with two independent instruments each of them having a measurement uncertainty below 5%. Firstly, the field profiles were determined by means of on spot measurement made at different time moments using a simple commercial instrument. Then, we adjusted these profiles, based on simultaneous and continuous determination of the time variability of B, obtained with our measurement system for automatic survey of the magnetic field. In order to make a complete characterization of the generated magnetic field, we also present, the time and frequency representations of B, a statistical processing of the results, and the profiles and maps of field when B is maximum/minimum. This is made in accordance to the field time variability (of about 8%), obtained during an hour of automatic survey of magnetic field in a single point.

A Measurement System for the Automatic Survey of the Low Frequency Magnetic Field
Ionel Pavel, Valeriu David, and Costel Donose
IEEE
In this paper we present a measurement system proposed, realized and calibrated for the automatic survey of the low frequency magnetic field. The instrument has a tri-axial sensor and three channels for waveforms processing in 50 Hz – 100 kHz frequency range. The waveforms of the magnetic fields are acquired using a National Instruments card and a virtual instrument created in the LabVIEW software, and then the data are processed and stored on a portable computer. Beside spot measurements, the instrument allows automatic long term survey of the magnetic field. The measurement system was calibrated by means of a simple method based on the standard field. The uncertainty of the instrument of about 15% is adequate for automatic survey of magnetic field.

A Survey of the Magnetic Field in a MRI Area
Ionel Pavel, Valeriu David, and Alexandru Constantin Podaru
IEEE
In this paper we present the results of the magnetic field survey in the neighborhood of the magnetic resonance images (MRI) scanner. By using both commercial instruments and an automatic survey system realized by us, we try to study the temporal and spatial variability of the background magnetic field in a hospital area. The maximum values of the magnetic field were given in the Technical Room, namely 8289 nT, near the MRI scanner gradients panel. Although the magnetic field values are below 9% from the maximum admissible values by ICNIRP, there are many points from the Technical Room where the values exceed 0.4 μT, which carry health risk, especially for children.

Analysis of the influence of the current drawn by the appliance on the close magnetic field
Silviu Ursache, Eduard Lunca, Alexandru Salceanu, and Ionel Pavel
IMEKO International Measurement Confederation
<p class="Abstract">The development of technology and the corresponding increase in living standards imply the generalized use of the most diversified and sophisticated equipment, a distinct, significant category being household appliances. The frequent presence of these devices close to a person’s heart, eyes, or brain naturally gives rise to concerns about the level of the associated (low-frequency) magnetic fields. The main objective of our paper is to study the possible correspondence between the low-frequency magnetic field generated by some household appliances and their current consumption. The proposed measurement system consists of the hand-held triple axis 480826 EMF Tester manufactured by Extech Instruments and the 80i-400 Fluke clamp meter. The performed measurement methodology takes into account the operating principles of the appliance. We perform measurements for a large selection of devices (47). The measuring point for the magnetic field is set at 30 cm from the source. Finally, by applying the Biot-Savart law to the previously determined drawn current, we calculate the magnetic field. We also compare the corresponding, directly measured values and analyze them.</p>

Actuating and controlling electrical circuits by means of virtual instruments
Costel Donose, Cristina-Mihaela Schreiner, Alexandru-Constantin Podaru, and Ionel Pavel
IEEE
This paper deals with two virtual instruments used for acting and controlling electrical circuits. Due to their working concept, these instruments have high flexibility for improvement, which makes them suitable for developing electro-technical virtual laboratories with affordable hardware and software resources.

Virtual monitoring of electrical circuitry
Costei Donose, Cristina-Mihaela Schreiner, Alexandru-Constantin Podaru, and Lonel Pavel
IEEE
The use of virtual instruments has a very important role in both specialized laboratories and academic ones. Because it is a modern method, it provides increased comfort in monitoring electrical circuits in the long term, as well as reduced costs of implementing and developing laboratories. This paper deals with the efficiency of virtual instruments in monitoring electrical circuits as compared to that of conventional devices. The built equipment can measure three physical measures in real time and offers graphical representations for each value. This also offers a new perspective on new trends in didactic methodology for pupils.

Study on the relationship between magnetic fields generated by home appliances and associated drawn currents

On a survey of the magnetic field in a commercial area

On the survey of the magnetic fields in power distribution substations
Ionel Pavel and Valeriu David
IEEE
In this paper we present the results of the low frequency magnetic fields measurements inside of two transformer and distribution stations in the country of Iasi. We made measurements in different areas inside two stations, near magnetic field sources and in control rooms, by using measurement instruments, which permit both spot measurements and long term survey of magnetic fields. The highest values of the field were obtained on Section 4 of Station 1 (9845 nT) and in Station 2 near the electrical transformer (7408 nT). So, maximum values obtained in the transformer stations were under 10 μT, which means that the value of the magnetic field is less than 5% compared to the maximum allowable by ICNIRP.

Automatic long term survey of magnetic fields in residential areas. Instrumentation and measurements
Ionut Nica, Valeriu David, Ionel Pavel, and Andrei Salceanu
OAIMDD - EcoZone Publishing House
Abstract In this paper we present the results of the long term survey of the low frequency (50 Hz 20000 Hz) background magnetic induction (B) in some residential areas. Firstly, we present the triaxial measurement system proposed, realized and calibrated by authors, which has an uncertainty of about 5%. This instrument can make the automatic long term survey with the characterization of the magnetic fields, being adequate to estimate the human exposure. We used our instrument to perform both spot measurements (time and frequency domain representations of the three fields’ components) and an automatic long term survey of the field components and of the resultant magnetic field, with their recording and statistical processing. Statistics were made for hours, days, weeks, and a month. The mean values of background magnetic fields for an 8 day survey period in a laboratory was 139 nT and 50 nT for a 32 day survey period in an apartment kitchen.

Ionel Pavel

EDUCATION

RESEARCH INTERESTS

Scopus Publications