Stelian Gal

On-line monitoring of OHL conductor temperature; live-line installation

This paper shows the Live working technology to install the On-line Monitoring system on Overhead lines. The Monitoring System, which is based on the contact-free SAW-technique, is introduced. During periods of high ambient temperatures, low wind speed and high electrical system load conditions, monitoring and analyzing regional areas of the transmission network can be essential to evaluate the conductor operating temperature. The temperature of the conductor at the point of installation can be measured and the data transmitted wirelessly to a data collection point.

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

Smart Grids: Romanian experience in on-line monitoring and condition assessment of high voltage substations

The paper presents the results of the correct on-line evaluation of the current technical condition of the electrical equipment in high voltage substations owned and operated by Romanian Power Grid Company - CNTEE Transelectrica SA, using intelligent monitoring systems. The paper describes parts of the intelligent systems dedicated to on-line monitoring of all primary equipment used in the 400/110 kV Darste substation (the 400/110 kV Darste substation is the first high voltage substation completely on-line monitored in Romania). The complex system created for the on-line monitoring of 400/110 kV Darste substation includes 167 NOVA EMCSIT systems designed for the on-line monitoring of power transformers, shunt reactors, circuit breakers, disconnectors, voltage/current transformers and surge arresters. These intelligent monitoring systems are used stand-alone or within the integrated system for on-line monitoring and condition assessment of a substation. The paper also describes NOVA INFOStation - the software that integrates the mentioned intelligent systems as a whole and also links them to Transpower - the integrated software designed for managing the technical condition and maintenance of the substation equipment: power transformers, shunt reactors, current and voltage transformers, circuit breakers, disconnectors and surge arresters in the Romanian Transmission Power Grid.

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.

The Power Quality Monitoring Systems in Romanian power grid

Transelectrica is the Romanian Transmission System Operator (TSO) and the Metering Operator of the Wholesale Electricity Market (WEM). It is deploying a nationwide Power Quality Monitoring System (PQMS). The PQMS has been operational since October 2005. The paper presents preliminary measurements results obtained from PQMS. The first part of the paper provides a description of the Power Quality (PQ). According with these regulations, TSO has to monitor the PQ parameters. The second part presents the most important permanently analysis of PQ parameters, in the Points of Common Coupling (PCCs), between TSO and the Distribution Systems Operators, at 110kV and between TSO and the Eligible Customers (EC), at 220kV. The third part presents the results from the PQ temporary monitoring system, the propagation of distortions around PCCs, at high voltage levels, measured with the portable PQ instruments. The final part contains conclusions and recommendations for future development.

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.

Theory of Informational Species and its implications in the power system protection, measurement and control systems

The Theory of Informational Species is –in a way- a theory of The Mind. It is –if we want to cloud our minds with words, as some could say — the most “fascinating” technique that came about in artificial intelligence. TIS is certainly a new challenge, one which the intelligence of Applications — concrete ones — where TIS is implemented has already imposed all over the world.

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.