George A. Florea

An original approach to the biological impact of the low frequency electromagnetic fields and proofed means of mitigation

It has been very clearly asserted that the electric and magnetic fields produced by the electric network may cause physiological effects due to the currents induced into the human tissues exceeding certain levels, but the magnetic fields with inductions lower than 1.2 μT may also produce biological impacts, decreasing the immune capacity, as resulting from the laboratory analyses correlated with epidemiological studies. This paper presents a new approach to the biological effect of the 50/60 Hz electromagnetic field on humans therefore using the concept of bioenergetic fields. Prof. ANCU DINCAs discovery consists in the drastically reduction of the effects of the electromagnetic field on the people placed in their neighborhood by placing passive autoconvertors close to the electromagnetic field generators. Reduced effects can also be obtained by applying some personal devices to regenerate the energo-informational field of the person within zones characterized by relatively high values of the magnetic induction. The measurements made in different locations with high values of magnetic field inductions, i.e. close to post transformers or inside the extra high voltage substations, have shown the advantages of both protection devices used.

Safety of the Personnel Working on Multicircuit Power Overhead Lines Implies the Precise Knowledge of the Magnetic Induced Voltages. Algorithm, Software and Comparison With Measurements At Real Scale

There is an increased need to perform some maintenance operations on a de-energized circuit of the multicircuit lines with other energized circuits. Applying the Std 524-2003 to calculate the magnetic induced voltages in the de-energized conductors does not solve the matter accurately. A precise algorithm and software were developed, modeling both the transversal and longitudinal geometric and electric parameters of the multi-conductor system, independent of the number of spans and conductors, comparisons with measurements being available, too

Case study on increasing the transport capacity of 220 kV DC OHL Iernut-Baia Mare by reconductoring using LM technologies

In 2009 we have celebrated 30 years since the first live maintenance techniques (LMT) have been carried out in Romania. This paper, in acknowledgement of the Romanian Live Maintenance Associations valuable activity in this field, is tackling a major issue for the Romanian Power Grid Company Transelectrica S.A.: the increase of the overhead line transmission capacity applying reconductoring with high temperature low sag (HTLS) conductors. The authors are proposing the use of live maintenance techniques, which considerably reduce the overhead line unavailability.

Personal Filters for Live-line Workers to Mitigate the Biologic Impact of the Low Frequency Magnetic Field

Except the physiological effects the magnetic field of industrial frequency produces biological effects as well, at values much lower, as resulting from some laboratory analyses combined with epidemiological studies. An alternative survey was initiated by the Russian scientists who discovered the subtle field accompanying the electromagnetic fields as being responsible for the biological negative effects. The Ancu Dinca filters, based on organic macromolecules derived from plants, neutralize the negative effects of the magnetic fields by reducing the subtle fields.

Live — Line surge arrester installing on a mountain section of the 400 kV Gutinas-Brasov o/h line (between towers 94–100)

The 400 kV Gutinas-Brasov o/h line is located in a mountain area with rocky soil. Because of the thick ice covering the conductors, during the winter times, causing the shieldwire breaking, the shieldwires were dismantled in the sections 94–100 and 130–145, long time ago. Without the shielding screen of the shieldwires those sections were left open to be struck by lightning. To reduce the lightning impact surge arresters were installed in two stages, the 2006 one, for the section 130–145 and the second one in 2013, for the section 94–100. Based on the first stage experience numerous improvements were applied for the second stage. No more lightning caused outages were recorded from the date of the first stage finalizing (2006–2016). Compared to the previous outage situation stating 4–10 outages per year, a very clear conclusion was drawn: a performant solution to protect the lines without shieldwires against the lightning strikes. Some improvements were proposed to the arrester manufacturer to increase the arrester component safety.

Assessing the remaining life time of 220 kV and 400 kV OHTL and the required measures for the coordination of remaining life times of the various constructive elements of lines

The paper makes an analysis of the eighteen 220 and 400 kV overhead electric lines belonging to C.N. Transelectrica — Sibiu Branch (TSO) on the basis of a unitary methodology for assessing their technical state and taking into consideration the different types of expertise conducted until now, including the multispectral analysis from the helicopter of seven lines. Performance criteria for insulators, risk analysis of special route area and maintenance strategies to extend the normal life time have been established. Considering that different constructive elements of the line, located in a certain area, have different life times, concrete measures of lines alignment to obtain convergence of the partial remaining times have been established. Special attention was given to lines with major importance in the national electric system, proposing measures to increase their reliability based on detailed expertise methodology.

A more accurate algorithm and software to calculate the magnetic induced voltages in multiconductor systems

Because of the necessity to perform maintenance on one of the circuits of the high and very high tension double circuit lines that have one of the circuits operational, a case that lately becomes more frequent, the calculation of the currents and induced tensions in the circuits conductors that is under induction is required to establish safety working conditions. This paper does not intend to modify the standardized established limits for touching tensions in normal conditions or short circuit of the inductor conductor, but proposes a mathematical model and the associated software that will give more precise results than those resulting from applying the methodology and software from IEEE Std. 524-2003 annexes.