Open Access
Access granted
Subscription Access
No 5 (2023)
Articles
Comprehensive Scientific and Methodological Support for Modeling and Optimization of Heat Energy Markets
Abstract
Heat supply is the most important area of energy services provided to a wide range of consumers. This industry determines the well-being of society, social stability and competitiveness of the economies of many countries of the world. The processes of energy liberalization that began in the early 1990s led to the emergence of new forms of heat supply management based on market interaction among producers and consumers of heat energy. In market conditions, the problem of optimizing heat supply systems becomes much more complicated, and its structuring becomes multivariate depending on the characteristics of the industry organization. To solve the problems of optimal functioning and development of heat supply systems in changing conditions, along with existing optimization methods, it becomes necessary to use new approaches focused on solving problems in some specific uncertain situations characterized by conflicting interests of the parties, and often defined as conflict. The paper presents a comprehensive scientific and methodological approach based on mathematical modeling for solving problems of managing the development and operation of heat supply systems in a market economy.
3-18
Reliability Properties in the Decentralization of Power Industry
Abstract
According to the energy strategy until 2035, energy transition in Russia is aimed at creating intellectual energy systems and orientation to distributed energy. The article proposes to consider distributed energy as the necessary component to the “large” energy, which allows you to increase efficiency, primarily in terms of power supply reliability. In Russia, the basis of distributed energy is cogeneration low power sources. Based on these sources and distribution networks of medium and low voltage, balanced local intelligent power systems (LIPS) are created. The integration LIPS in centralized power supply systems allows you to get significant systemic effects. The aim of work is to study the influence of the integration LIPS with re-gional power systems on the reliability indicators of power supply.
19-39
Application of Search Algorithms in Determining of Fault Location on Overhead Power Lines According to the Emergency Mode Parameters
Abstract
Identification of fault locations (FL) on overhead power lines (OHPL) in the shortest possible time allows to reduce the time for shutting down OHPL in case of damage. This helps to improve the reliability of power systems. FL devices on OHPL according to the emergency mode parameters (EMP) are widely used, as they have a lower cost. However, they have a larger error than FL devices that record traveling wave processes. Most of the well-known algorithms for FL on OHPL by EMP assume a uniform distribution of resistivity along the OHPL. In real conditions, this is not the case. Application of these algorithms in FL devices on OHPL with inhomogeneities leads to significant errors in calculating the distance to the fault location. The authors proposed the use of search algorithms for u-nconstrained one-dimensional optimization to increase the speed of implementation of iterative procedures in FL devices on OHPL by EMP. The authors have developed recommendations for choosing optimization criteria, as well as options for implementing computational procedures. Using the example of a two-sided FL on OHPL, it is shown that the use of search algorithms can significantly (from tens to hundreds of times) reduce the number of steps of the computational iterative procedure. The implementation of search algorithms is possible in the software of typical relay protection and automation terminals, without their hardware upgrade.
40-59
Limiting and Binary Schemes of Vapor Bubble Growth in an Infinite Volume of Liquid
Abstract
The problem of spherically symmetric growth of a vapor bubble in an infinite volume of a uniformly superheated liquid is considered. The concept of limiting growth schemes, each of which is determined by the influence of a single physical factor, is put forward. An analytical approximation of the Scriven integral is proposed, its asymptotics are analyzed. Analytical solutions for binary growth schemes with due account of the influence of two physical factors on bubble growth are obtained.
60-78