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The paper deals with the PI and PID controllers settings. The research includes an overview of the most commonly used control quality criteria. It was assumed that the controlled system can be approximated by first order inertia with dead time. The control systems that includes the model as well as the PI and PID controllers were analyzed in context of control quality taking into account ITAE criterion...
Digital relay is an important part of the power system and actually is based on fundamental frequency (50–60 Hz). Digital filter is applied for further processing and performs mathematical operations on sampled values. The digital signal processing (DSP) becomes more applied and used in proactive relays. Obviously, DSP is used in wide range of application (controls, radio, communications and other...
This work analyzed the efficiency of the gasification process applied in Urban Solid Waste (USW), since tests carried out in a pilot plant, as a way of studying the feasibility of applying the process in the production of a gas for burning in a boiler and generation of electricity, on a steam turbine and generator system, on commercial scale. The results indicated the feasibility of the process both...
The paper presents mathematical models of the key components onboard autonomous power supply system (ASE) plane "conventional" and more electric aircraft MEA "More Electric Aircraft". The subject, and also the aim of this work is the analysis and simulation of selected components of the power system of modern aircraft (synchronous generator, integrated starter/generator, voltage...
The operation of the off-grid system consisting of projectable PV panel array and two dieseis (one in reserve) generators SDMO J200K with 160 kW installed capacity are considered in this article. The aim of the study is to make a stability analysis of the system with an evaluation of problems can occur and their possible solutions, which keep the system operational. Three possible faults at generator,...
This paper describes procedures for modelling of two-winding off-load tap-changing transformers in two alternative simulation tools for load flow analysis — DYNAST and SimEPS. For both softwares, respective transformer models and other necessary simulation steps are introduced. Determination of all input parameters is presented along with the verification of results for single-phase transformer model...
This paper deals with the solution of transient phenomena during the connection of the photovoltaic power plants. There was investigated the impact of the failure of current protection for renewable energy sources during the network disconnection. There was verified the possibility of network operation during the islanding operation. Failure of network protection represents the significant hazard...
This work proposes different methods to calculate the sensitivity of system parameters based on graphic analysis. From percentages variations in base values of the parameters, one-at-a-time measures are taken to the construction of a graph that expresses the impact on the output caused by variations in the inputs. Two case studies are proposed, with simulated and experimental data, in which the proposed...
The insulating liquids for power transformers are still evolving area. The current trend is to move away from currently used mineral oil because it poses a threat to the environment and use the renewable, biodegradable nature ester oils instead. These oils are now well known but what keeps them from widespread usage are unbalanced properties. In some areas these natural oils excel (fire point, sulfur...
The purpose of this work is to develop devices capable of identifying sign language characters and comparing them in order to verify layout with better accuracy and robustness. The recognition is performed using Artificial Neural Networks and all the input data are signals from flex sensors, accelerometers and gyroscopes, positioned differently on each device. After being trained, validated and tested,...
This paper deals with the operating of so called low-cost lighting systems fitted with LED light sources. The reason for drawing up the paper was a notification of qualitative changes in luminous flux of implemented lighting systems. It is currently possible to produce relatively cheap LED luminaires fitted with available white LED. Since the low-priced LED go hand in hand with their qualities, these...
The pollution of external insulation of power equipment has a significant impact on the lifetime of electrical equipment. The paper is focused on the possibility of using monitoring leakage current through the external insulation of hv surge arresters as indicator of pollution. In the experiment the modified procedure for the preparation of the polluting layer was used. The leakage current on the...
Evaluation of current-carrying capacity of power cables and selection of cross-sectional area of their conductors are mainly performed in accordance with requirements of EN, IEC or IEEE standards. However, these standards do not provide all methods of cables installation and location which occur in practice. Thus, in some cases, performance of advanced modeling of various thermal phenomena, affecting...
The article describes using of power semiconductor converters in the area of accumulation of electrical energy in the Technology Centre Ostrava (TCO). Further discloses design of the power semiconductor converters, its internal structure, utilization of energy and the main parameters and focuses on the issues of the capacitor bank — determine the power loss of capacitors, determine the lifetime, determination...
In this paper, the problem of optimal power flow (OPF) is solved in a system integrated with wind farms with the aim of reducing the cost of power production and the reduction of power grid loss by applying the Grey Wolf Optimization (GWO) Algorithm. The variable nature of wind farm output is modeled using two additional cost components corresponding to the states of under estimation and over estimation,...
This paper aims to identify the critical line on the basis of power system cascading failure search. The proposed critical line identification strategy considers the factors of power flow and topology. Accordingly the electrical betweenness and transmission power are employed during analysis, of which the corresponding theoretical basis is deduced in simple systems. Next follow-up step is to apply...
This paper's purpose is to investigate the energy efficiency with the installation of the photovoltaic system in residences of social interest, seeking mainly to meet the demands of higher consumption of electric energy such as the showerhead. An estimatedproposal of the Energy Efficiency Program carried out by the Goiana Housing Agency in which it will install 1,199 photovoltaic systems in the housing...
In this paper the switched reluctance generator (SRG) is explored considering the improvement of its efficiency. This machine generates a DC power that is directly related to input driving parameters. Simulation results are presented bringing a case study of parametric regression to track the best efficiency for any input parameters: excitation voltage and turn off angle. A method known as parametric...
Waste engineering wood in the form of chipboard and plywood is a potential source of renewable energy in boilers for biomass combustion. The conditions causing the silicate melt slagging during combustion were studied by proximate analysis, mineralogical analysis using X-ray diffraction, scanning electron microscope with energy dispersive analyser and thermogravimetry. Slags are formed by refractory...
Congestion management is one of the technical challenges in the power system. Privatization and market liberalization lead to stressed operating conditions in existing and future power systems. Additionally, the increasing complexity of the power system results in an increased need for information on the actual grid condition and intelligent control methods. Unfortunately, measurement data from each...
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