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Turbine fast valving is one way to preserve the stability of power systems in case of emergency excess power. The determination of optimal setting parameters of turbine fast valving is a rather complicated task. It is connected with the necessity to determine the parameters of an electrical signal, which controls by means of an amplifier the position of control valves and, accordingly, the value of the output turbine power. The amplitude, duration, as well as the form of the electric signal influence the speed and depth of turbine unloading; they also determine the character of transient process development, including in the post-emergency mode. The proposed approach differs from the currently used one in that the optimal electrical signal shape is selected by multiple detailed modelling in power system simulators, rather than one of three to five initial settings determined at the turbine manufacturer without taking into account the response of the power system. Thus, when using complete and reliable information regarding the processes in the turbine and generator equipment, its control systems, and the power system as a whole, it becomes possible to form the necessary shape of an electrical signal in the event of losing stability in a place of interest in the power system due to the occurrence of an emergency excess of generated active power of various values. The developed approach was tested, and the results of the study were verified by the field data. [ABSTRACT FROM AUTHOR]

At present, due to the increase and significant complication of the electric power system (EPS), the task of maintaining the stability of the EPS is becoming increasingly important. Due to the fact that, in case of significant disturbances in the EPS, the processes occurring can lead to large synchronous swings of the generating equipment or loss of stability. When disconnecting the intersystem communication or a powerful load in the excess part of the EPS, an emergency excess of generated active power occurs, as a result, the frequency begins to increase, and the load-frequency control system is not able to cope with such an accident, due to its slowness. In this case, it is necessary to use the means of emergency automation to eliminate the surplus of active power. One of the most effective methods is fast valving automation. However, its effectiveness directly depends on the quality of its setting - which is a rather difficult task, since for its implementation, a complete mathematical model of the turbo-generator is required, taking into account its control systems and boiler unit. [ABSTRACT FROM AUTHOR]

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Copyright of Przegląd Elektrotechniczny is the property of Przeglad Elektrotechniczny and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Nowadays in the world a lot of attention is paid to the integration of renewable energy sources, especially wind power plants, into existing electric power systems. However, the modern simulation tools usage based on numerical integration for studying and assessment of renewables impact on transient processes in EPS is always associated with different simplifications and limitations. In this regard, the authors suggest the Hybrid Real-Time Power System Simulator (HRTSim) usage for comprehensive and accurate simulation of large-scale EPS with RES. The results of the synthesis of the wind turbine mathematical model as a part of the specialized module for the HRTSim are presented in the paper. The developed means are intended to solve the issue of this hardware-software simulator upgrade for comprehensive and adequate modelling of wind power generation facilities. [ABSTRACT FROM AUTHOR]

In this paper, the structure of installed capacity of power plants in the power system of Russia is presented. The growth of power plants based on renewable energy sources can be seen. Based on the foregoing, it can be concluded that the prospects for the development of the global electricity industry are determined by the study and direct operation of energy facilities whose fuel resource is renewable energy sources, in particular, the sun and wind. However, the widespread installation of renewable energy sources at the moment is not possible, due to existing restrictions, the fundamental of which are technical limitations. One of the research tasks is to determine the optimal location of power plants based on renewable energy sources and its installed capacity. Although, if this task can be effectively solved by using optimization algorithm, the task of ensuring correct operation in normal and emergency mode of power system is more complex and requires additional research and analysis. [ABSTRACT FROM AUTHOR]

The electric power system elements are designed to transmit electricity to consumers. To ensure the transmission, in the design and construction of the power system provide for increased cross-section of lines, throughputs of transformers, cost for other procedures. To find the magnitude of the increase, it is necessary to determine the maximum power flow through the element. This is important for the digital substation operation, where all actions are subordinated to the automation elements, and the ability to control power flows, through the electrical equipment management, has the primary task. This solution is not absolutely effective, since it's not known how much the measures are related to the accident probability. It's needed to know where the maximum power consumption can appear. Therefore, it is necessary to determine in a non-deterministic form how the available power plants power is distributed over the grid to ensure power supply. The main problem is that obtaining the probabilistic characteristics of the parameters by standard statistical methods has no practical solution. In this regard, the method of selection of interval boundaries of input and output data (SIBD) is proposed, and its application for obtaining probabilistic characteristics of electrical quantities and their imbalances. [ABSTRACT FROM AUTHOR]

Electric power systems are becoming more complex. This is due to the widespread use of renewable energy sources (RES) and FACTS devices. At the same time, protection devices for equipment and automation of power systems are becoming subject to influence from new devices. The article pays attention to the study of such influence from the side of RES and FACTS devices on the operation of one of the most important automation systems ensuring the stable operation of the power system - out-of-step protection (OSP). At the first stage of the project, the main reasons for the difficulty of setting up resistance control devices of OSP in networks with FACTS devices and RES were identified, which are related to the fact that the parameters of these devices vary depending on the operation mode, therefore, the zone of the OSP resistance relay should also be changed. Based on the analysis, a new approach to the study of the functioning of OSP in power systems with FACTS devices and RES has been developed. The performed experimental studies confirm the theoretical research. [ABSTRACT FROM AUTHOR]

The introduction of modern technologies significantly changes the modes of operation of electric power systems (EPS) and has an unpredictable impact on the functioning of relay protection devices (RP), in particular distance protection (DP). It is impossible to adequately measured the impact without detailed modelling of both EPS and RP devices. The subject of this research is the development of a detailed mathematical model of digital distance protection (DDP). When designing such a model, both current and voltage measuring transducers, analogue digital relay protection devices, and digital signal processing were taken into account. In this paper, studies are aimed at assessing the correctness of the third stage of the DP using the detailed and simplified model of the DDP. The operation of the compared models is tested on a 39-bus New England system via MATLAB Simulink simulation data, and a comparative assessment is provided. Such detailed DDP mathematical model in combination with an adequate EPS simulator could be used further for solution of different tasks, such as development, design, analysis, testing and setting of RP algorithms. The article presents the results of preliminary studies of the mentioned problem. [ABSTRACT FROM AUTHOR]