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The anisotropy of the magnetic materials is an important parameter in many cases, especially in modern applications, like sensors or drives. This paper proposes a new approach to the study of the behavior of the intrinsic and extrinsic properties of these materials depending of the orientation of the sample in a magnetic field. By controlling a Vibrating sample magnetometer (VSM), it could be possible...
Increasing the safety of a navigation lock, by creating a modern and efficient communication between the human operator and the machine, for 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 modern and efficient centralized tracking equipment for...
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...
All electronic pieces of equipment having fast and frequent load variations are widely used today due to some obvious benefits like energy efficiency, flexibility, low costs and even reliability. But, they also produce some important disturbances on electrical distribution lines, mostly harmonics or fast changes of the reactive power. Due to all these issues, power quality aspects become essential...
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 paper presents a new approach developed in order to provide a better design solution for the 110–123 kV, SF6 type switches. Having an efficient computer based tool for the design of such important equipment it's always a challenge for any high voltage equipment manufacturer worldwide. We have to mention, in the first part of the paper, the particular technical characteristic of SF6 HV switches...
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...
Fuzzy logic controllers, FLCs, are elements of the artificial intelligence, and, today, they are widely use in command and control of many industrial processes. It involves the acquisition of better signal wave forms at the output and the reduction of all oscillations (in case of electric drives, we consider speed variation, torque variation, current variation for all the three phases ore more) in...
Nowadays, in Romania, centralized district heating is still widely used in many Romanian cities. All the heating facilities were made during 1950–1970. The whole system is largely improper due to large amounts of heat leakage, lack of heat and energy efficiency measures and financial shortages. All these limitations are made worst due to the continuous limitation of resources and also due to the high...
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...
The problem of interpolation a set of data is an old one, but the demanding of flexibility and high speed in operating on-line and in real time processing need to find new methods and improve the old ones [1]. The main properties of B-spline functions offer the possibility to implement algorithms of interpolation in a faster and optimal manner. A function can be represented by B-spline functions with...
District heating is largely used today in many Romanian cities. But, having an efficient heating system on such a large area means introducing an adequate command, control and measuring system, too. Due to the continuous limitation of resources and also due to the high price of the energy, the measurement and the management of the heating agent is a real priority for the power plants and also for...
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 problem of interpolation a set of data is an old one, but the demanding of flexibility and high speed in operating on-line and in real time processing need to find new methods and improve the old ones [1]. The main properties of B-spline functions offer the possibility to implement algorithms of interpolation in a faster and optimal manner. A function can be represented by B-spline functions with...
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...
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...
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