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A complex multi-component system consists of finite number of non-identical components that can be realized as maintained components with different maintenance modes. We distinguish between four component models: non-repairable components, repairable components with corrective maintenance, repairable components with latent failures that are identified by means of preventive maintenance and component...
This paper presents an inclusive set of EMTP models used to simulate the cause of voltage sags such as short circuits, transformer energizing, induction motor starting. Voltage sag is usually described as characteristics of both magnitude and duration, but it is also necessary to detect phase angle jump in order to identify sags phenomena and finding the solutions, especially for sags due to short...
The paper contemplated the possibility of using the power thermobattery with special converters that operate from voltages in the tens of millivolts. Two such converters have been developed; their characteristics have been measured and documented. The only thermobattery with such a converter is able to supply low-power devices from the temperature difference of one tenth of a degree Celsius.
This paper deals the mathematical description of an asynchronous machine. Differential equations are then used to create a dynamic model of asynchronous machine. For the possibility of evaluation the quality of the created model are created at the conclusion the basic characteristics of representing the asynchronous machine. Graphs show almost identical measured and the simulated values. The model...
This paper describes the analysis of power generating units and their implementation, these are located within the technological centre in Ostrava-Vitkovice. Further issues concerned in this paper deal with digital simulation using computer model created using the EMTP — ATP software to evaluate particular process courses that may occur on the power inverter installed in the technological centre....
Paper deals with the analyses of electrical power network reliability parameters connected to maintenance. Knowledge of the component reliability parameters in power networks is necessary for the reliability computation and also for reliability-centered maintenance system. Component reliability parameters are possible to retrieve only with accurate databases of distribution companies. Such a database...
The implementation of Reliability Centered Maintenance into Preventive Maintenance Plan scheduling is one of the possible paths towards cost reductions in the fields of diagnostics and operating personnel. There is also the assumption of maintaining acceptable reliability of individual devices within the entire network. The devices to be considered suitable for application of RCM concern network elements...
Energy crisis around the world and implementation of so-called Package 3×20 where one of its demands aimed at increasing the share of renewable energy sources in overall balance, result in a significant increase in the interest in geothermal energy, and thus in the production of electricity from geothermal sources. Unfortunately, in Poland and the Czech Republic we are dealing mainly with low and...
In this paper, modeling of STATCOM for regulate the voltage in power flow calculation is proposed. Based on power flow, the proposed technique has been presented and tested on 26-bus power system. The results proved the correctness of the proposed technique. The influence of the STATCOM on regulating voltage and decreasing power losses has also been discussed in detail.
Voltage sags caused by short circuit in a distribution system can heavily influence power quality parameters. In this paper an application of custom DVR is analyzed and proposed for mitigating of voltage sags considering unbalance, voltage sags and fluctuations and distortion of voltages in an industrial distribution system. The paper presents system operation and controller design approaches, verified...
The expansion of renewable energies is progressing strongly. The influence on the power supply networks by the volatility of the infeed must be met with new concepts. In this paper we investigate the possibilities of integrating microgrids as a harmonious unit in the power supply network to support further expansion of RES power plants. In this paper a differentiation of microgrids from similar network...
In 1997 cooperation began between the Faculty of Electrical Engineering and Computer Science and the power company CEZ on a joint project that involved monitoring selected voltage quality parameters. Over the course of several years measurements were carried out at 59 points of the distribution system at a low voltage (LV) level and their power supply nodes at medium voltage (MV) and high voltage...
This paper deals with a description and partial analysis of energy production units and their implementation in the laboratories of ENET technological centre in Ostrava - Vitkovice. The paper refers to individual types of conventional and non-traditional sources of electric power that are connected to the technological centre distribution grid, together with analysis of their topological configuration,...
This paper focuses on restoration methodology for 110 kV power lines. Principle of reliability centered maintenance is used in the restoration method. The input data is typically collected in the operation of the distribution network. The data distributed concerns the power, the database of faults and the effect of failure. Functional application is used to determine the results and analysis.
The development of the nano-silver production technology as well as its unquestionable biocidal properties have given rise to a great interest of the electric power production market in the use of the nano-silver as an agent improving the maintenance of biological stability of the cooling water. The laboratory tests performed on the water collected from the cooling tower circulation in the Lagisze...
The paper describes another part of the work to define the order of maintenance for transformers rated 110 kV / MV. When determining an optimum maintenance sequence, we require the appropriate parameters of technical conditions and operational importance. The database of input values referring to the technical condition by importance has been completed over the recent year. This paper describes both...
This paper deals with the agenda associated with management of a power control centre within a power supply plant together with operation of a local distribution system within the premises of such power supply plant. The main part aims at the analysis of power supply reliability concerning a selected section of the system at 6 kV distribution plant. The background data used for calculation are sourced...
This document deals with the need for construction of new pumped storage hydroelectric power plants. Special attention has been dedicated mainly to the search for suitable locations to place PVEs, including utilization of new options of their placement.
This paper deals with the legislative framework amending supply of electricity. It outlines an analysis of the important quality parameters of electricity supplied by small hydropower stations in the waterworks buildings in practice.
The paper describes 110 kV power lines restoration method based on reliability centered maintenance and its development. The database of faults is used to determine technical condition. The distributed energy and effect of failure are used to determine the importance of line. A functional application was developed to debug the methodology.
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