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Not very applied in today materials engineering, diamagnetic levitation offers some distinct features for micromagnetics and many other technical domains. It can provide frictionless bearings for micromechanical sensors applied to measure some types of weak forces, resulting from various physical effects, especially in nanotechnologies. Applied in the situation of these micro machines, diamagnetic...
Increasing the safety of a navigation lock, by creating a modern and efficient communication between the human operator and the machine, for a prompt and accurate information offered to the operator, about the status of the equipment it serves, it is a requirement of today navigation worldwide. This paper aims to describe the implementation of a modern and efficient centralized tracking equipment...
Predictive maintenance of high voltage devices is a major issue for all power providers, due to costs and complexity. This article provides some theoretical and experimental principles which can be useful for all maintenance operations performed on high voltage switching devices and some simple methods applicable for assessing the status of all their contacts. Some of the aspects described here are...
The effective protection of each type of sensible electronic piece of equipment against any type of over voltage (including direct or indirect lightning applied on power supply) is a big issue for power system specialists. Some of the most reliable electronic devices used in order to protect against overvoltages are all voltage metal oxide varistor based surge-arresters. These varistors are produced...
This article presents a small scale complete system, used for power quality assessment, developed by the authors, for the Romanian National Grid Operator, Transelectrica S.A. Most of the Power Quality (PQ) analyses carried out today worldwide are performed at the end user (the electricity consumer). The assessment of the main PQ parameters is mandatory to be done at all voltage levels, including high...
In order to perform digital signal processing it is necessary to reduce the effect of the noise on the signals. Some digital filters developed previously for signal interpolation are tested on different signals with noise. We study their effect and characteristics. The question about the right interpolation of a data set is not new, but it needs versatility and high speed in order to be correctly...
Metal Oxide Varistors (also known as ZnO varistors) are built in many types of overvoltage protection equipment, being one of the most common solution for surge arresters. They have a higher non-linear dependence between voltage and current, and a relatively high heat adsorption capacity in case of normal overvoltage pulses. Their current is mostly activated by temperature, so overheating can cause...
In the proximity of the high voltage overhead power lines and within the high voltage substations, several human beings and environment safety measures are necessary to be taken, imposed by the nature of all electromagnetic phenomena. These precautions have to be respected during power facilities exploitation. The recorded values using a powerful power quality and environment impact monitoring system...
The main topic of this article is related to a didactic methodology used for the IT based assessment of the influence of Power Lines and Equipment on Telecommunication Lines. Power is needed as well as telecommunications are in our society today. Power head lines are parallel or crossed with telecommunication ones, so influences could be electric, magnetic or even resistive ones. All these interferences,...
The main subject of this paper is to present a didactic procedure and an hardware equipment used for air pollution assessment and air quality assessment, nearby a thermal power plant, based on an expert system. The architecture of the expert system, both hardware and software, is described briefly as well as the main principles of the software involved. A didactic method used for transmitting to students...
This paper presents a dedicated software (as well as the associated hardware) used for power quality analysis. Power quality is one of the important objectives of the transmission and distribution network allover the world. Several aspects concerning the PQ monitoring interface between the transmission network and the distribution network are revealed for a 110 kV voltage level. This is a case study...
This paper aims to present the fundamental problems arising in case of photovoltaic (PV) systems modelling. The goal of these systems is to extract the maximum energy. There are determined the maximum power point coordinates – maximum voltage (U OPTIM ) and current (I OPTIM ), that are basic sizes for determining the maximum load resistance. The proposed control method is characterised...
Within metallic or insulated objects or vehicles, overhead power line electric field induces potential that could become dangerous when human beings are in contact with. Also, for human beings that are working within electric or magnetic concentrated fields, biological perturbations could occur. A power quality and environment impact remote-measuring system is presented within the paper. It provides...
The papers main goal is to present some simulation in designing a MIMO system for LTE in 800 MHz band for automotive industry. Section 2 contains some aspects about antennas used in the automotive industry and about MIMO systems. Section 3 refers to some characteristics of the Inverted F antenna (IF) and Planar Inverted F (PIF). The results for the design of an antenna system in the 800 MHz band for...
The paper presents a monitoring system for power quality and environment power facilities impact assessment. The high voltage installations' electromagnetic pollution is considered primarily within the analysis. The experimental results relate to substations within the Romanian Power Grid Company Transelectrica, Sibiu Subsidiary. The measurements have been performed for electric and magnetic field...
The protecting systems against overvoltages produced all over the world make more and more use of variable resistors based on metal oxides known under the name of varistors as they present a series of advantages when compared with other similar protecting systems. In this respect, the paper presents, besides a short comparative analysis of the protecting system, a Romanian concept concerning the realization...
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