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The activity of obtaining electricity using fossil fuels has produced a wide category of emission. The main pollutant released into the atmosphere from fossil combustion in order to obtain electricity and heat is sulfur dioxide. Taking account of this fact, there is a need of an environmental factors monitoring in nearby the energy complex. This paper contains an evaluation of air quality in vicinity...
In this article is presented the simulation of the primary control (the load frequency control) for two interconnected power systems in radial network In the paper is described the realization of the mathematical models related to the primary machine composed of the automatic speed regulator model in series with the turbine model. By simulating an imbalance between production and consumption in order...
In electro-energy an important problem is to ensure production and transport of electricity in optimum conditions and safety. In this respect knowing of the degree of aging of electrical equipment (transformers, cables, accessories, etc.) becomes a strategy matter of the maintenance management. Optimized and improved test methods and equipment for HV and MV power cables for the early detection of...
Development of urban traffic, travel highlights three significant phases: daily commute to and from jobs, afternoon trips to different areas of commercial or cultural interest, periods of “weekend”. These three phases can show great variety in structure and intensity of urban traffic, the composition of the car which has an important role, with great quality to ensure maximum comfort of travel. In...
This paper presents a concrete way of linking the JADE multi-agent system with the equipment (eg PLC, DCS, SCADA) comprised into a distributed industrial control system based on agents, using OPC servers. Industrial applications of multi-agent technologies are limited especially due to communication difficulties between software development environments with agents and with heterogeneous control devices...
This paper presents a system designed for the optimal use of thermal energy in residential buildings along with keeping human thermal comfort. It is proposed a distributed temperature control system achieving high precision for all the rooms at any external conditions and prescribed temperature dynamics. It was considered a heating process in a dwelling having a central heating system based on natural...
One of the most expensive AC tests, in terms of the necessary equipment, is the test of cables and generators insulation with high own capacity, both in the factory and on site after repair or for a prophylactic purpose. That is why in practice there are used either some very low frequency (0.1 Hz) even DC voltage or AC resonant and impulse testing facilities. For the last the capacity of the object...
1Taking into account the equivalent circuit of the induction motor considering the iron losses, its mathematical model was created based on the state equations in the stationary d-q frame, assuming that the magnetizing dynamic inductance is equal to the static one, which depends on the magnetizing current. After obtaining the state equations, containing the d-q stator and rotor current components,...
This paper presents the magnetic and thermal sizing of the prototype of an YBCO quadrupolar superferric magnet (QSM) for high gradient magnetic field. The design of an optimal polar piece is first addressed. Simpler 2D models are used to find design level details on the magnetic field spectra. Next, the heat transfer problem is solved. The heat leakage from the ambient is a menace to the QSM superconductive...
The discussed class of original hybrid wavelet algorithms is analyzed firstly relative to the decomposition vectors shape and periodicity in stationary regime. The studied signal corresponds to a current from the supplying network and has medium distortions within its first 4 periods, the other 2 being seriously affected after a fault. The noticed differences are responsible for different decomposition...
This article presents the study of connecting a lithium storage battery to the public distribution network. We are following the battery loading and unloading effects from the network and its influence on network parameters, namely: voltage, frequency, short term fliker, the total voltage harmonic distortion (THD-U).
Due to the increasing need to replace the petroleum based products, there's an interest in replacing the mineral insulating oil for electrical equipment with biodegradable vegetable oil. This paper presents a comparative experimental study concerning the ageing of mineral and vegetable oils used in power transformers. In this view, samples of mineral and vegetable oil were accelerated thermally aged,...
This paper is focused on the implementation of the different theories of powers and current decomposition methods in the compensating current calculation for three-phase three-wire shunt active filtering systems. They are grouped into two categories, depending on the type of coordinate system used in the processing measurements involved in calculations. The former is based on the phase coordinates...
A medium/low voltage transformer from a distribution substation for urban transports operating in a highly distorting regime is analyzed. Regimes of idle running, running with non-linear load, respectively fault (short-circuit) are presented from the theoretical point of view. The results yielded by their operation simulation using MATLAB / SIMULINK are discussed. Aspects related to the measurement...
The actual state and operation of the Romanian power system ask for a certain expertise in detecting the causes of electromagnetic perturbations and their evaluation in power grids. Consequently, all the aspects regarding the power quality issues became a common characteristic of the power systems' curricula within Romanian power engineering faculties. The students attending these classes are involved...
The transition to renewable energy sources and energy efficiency have become a central topic, also for the producing industry in Romania and all over Europe. Saving energy is on the agenda for companies as well as facilities and public institutions. Energy efficiency in companies can be controlled and systematized in an energy management system. The ISO standard 50001:2011 enables companies and other...
The paper is an extension of the study of the dynamics of a variable mass object in the case of a rocket. In the usual dynamics calculations body mass variable is not taken into account drag effect that characterizes the evolution of the Earth's atmosphere with a certain density ρ at a certain altitude H. In this study rocket flight can not be neglected. Instantaneous speeds are determined in two...
For condition monitoring of the power cable insulation system, different diagnosis procedures are available. The measurement of partial discharge (PD) activity is still an issue of great importance. This paper deals with the effect of the temperature gradient and different voltage waveforms/ frequencies on PD phenomena within voids of power cables insulation. The results of PD measurements and computer...
This paper presents a comparison between the numerical simulations performed for an electro-hydraulic servo-actuator using two different mathematical models. One follows to show the differences between the results obtained in the two cases, in order to choose the appropriate model if it is necessary to simulate larger systems which contains such servo-actuators. The first of the mathematical models...
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