Study of the influence of overvoltage on the quality of electricity in energy systems.

2020 ◽  
Vol 23 (2) ◽  
pp. 52-58
Author(s):  
S. SKRYPNYK ◽  
Keyword(s):  
Power Supply ◽  
Fire Hazard ◽  
Lightning Discharge ◽  
Quality Standard ◽  
Normal Operation ◽  
Electrical Network ◽  
Modern World ◽  
Electrical Networks ◽  
The World

Our world with its high technologies has long been deeply dependent on the quality of electricity supply. In most countries of the world there are national power grids that combine the entire set of generating capacity and loads. This network provides the operation of household appliances, lighting, heating, refrigeration, air conditioning and transport, as well as the functioning of the state apparatus, industry, finance, trade, health services and utilities across the country. Without this utility, namely electricity, the modern world simply could not live at its current pace. Sophisticated technological improvements are firmly rooted in our lives and workplaces, and with the advent of e-commerce began the process of continuous transformation of the way individuals interact with the rest of the world. But with the achievement of intelligent technologies, an uninterrupted power supply is required, the parameters of which exactly meet the established standards. These standards maintain our energy security and create a reliable power system, that is maintaining the system in a trouble-free state. Overvoltage is the deviation of the rated voltage from the value of the corresponding quality standard (frequency, sinusoidal voltage and compliance of harmonics). Overvoltage in terms of fire hazard is one of the most dangerous emergency modes of electrical equipment, which causes conditions that in most cases are sufficient for the occurrence of fire hazards (exceeding the allowable voltage leads to disruption of normal operation or possible ignition). Against the background of deteriorating engineering systems, increased power consumption and poor maintenance, power supply of electrical installations, the main causes of overvoltage in electrical networks are thunderstorms (atmospheric overvoltage), switching switches, uneven phase load in electrical networks, etc. The physical picture of internal overvoltage is due to oscillatory transients from the initial to the established voltage distributions in the conductive sections due to the different situation in the electrical circuit. In the conditions of operation of electric networks planned, mode or emergency situations are possible. Therefore, the ranges of overvoltage are determined by the range from several hundred volts to tens and hundreds of kilovolts, and depend on the types of overvoltage. Atmospheric overvoltage is considered to be one of the most dangerous types of emergency modes of operation of the electrical network. This overvoltage occurs as a result of lightning discharge during precipitation by concentrating electricity on the surface of the object, the introduction of potential through engineering networks and

Approach to the location of distributed generation sources in the structure of electrical networks

2021 ◽  
pp. 75-86
Author(s):  
A. Gai ◽  
◽  
V. Gulevich ◽  
Keyword(s):  
Electric Power ◽  
Quality Indicators ◽  
Distributed Generation ◽  
Power Supply ◽  
Alternative Energy ◽  
Electric Power Industry ◽  
Energy System ◽  
Electrical Network ◽  
Electrical Networks

Today, the electricity supplier is not able to declare the possible level of quality of electricity supply, and the consumer simply does not have the opportunity to buy such "high-quality" electricity. In such conditions, a differentiated approach to tariff formation is inevitable, which has been implemented in practice today, albeit in its infancy. Further improvement of the tariff-forming mechanism is impossible without creating a "flexible" dependence of the tariff on the quality indicators of the consumer's power supply. Quality indicators, in turn, are based, on the one hand, on the methods and approaches for their determination, and on the other, on statistically reliable data on the elements that make up the equipment in the "generation-consumer" chain. In recent years, there has been a tendency to change the concept of development of the electric power industry, since preference is given to the development of sources of distributed generation. Distributed generation is understood as a source of electrical energy directly connected to the distribution electrical network or connected to it by consumers. Ensuring the socio-economic stability of society and a decent quality of life for the population largely depends on the reliability and efficiency of the functioning of the infrastructure for the supply of fuel and energy resources, in particular, electricity. Excessive losses of electricity during its production, transportation and distribution, as well as an unacceptable level of harmful emissions into the atmosphere, are the cause of interruptions in power supply to consumers and even the threat of systemic accidents in the United Energy System (UPS) of the country. The introduction of alternative energy sources in electric power systems, in addition to reducing the harmful impact on the environment and solving the problems associated with waste pollution during electric power generation, will reduce the use of natural resources and relieve the backbone and distribution power lines. As part of the scientific search, an approach was proposed, which is the basis for calculations to determine the optimal installation locations for sources of distributed generation of an average overhead line. The results obtained are presented in the framework of a joint technical meeting of leading specialists of operating enterprises, the customer and the staff of the Department of Power Supply named after V.M. Sinkova NULES of Ukraine.

scholarly journals On the Mutual Influence of Voltage Control Modes and the Compensation of Reactive Power in the Electrical Networks of Industrial Enterprises

2021 ◽  
Vol 64 (3) ◽  
pp. 239-249
Author(s):  
V. P. Schasny ◽  
A. I. Zhukouski
Keyword(s):  
Power Supply ◽  
Reactive Power ◽  
Mutual Influence ◽  
Voltage Control ◽  
Reactive Power Compensation ◽  
Electrical Network ◽  
Electrical Networks ◽  
Industrial Enterprises ◽  
Technical Requirements

The efficiency of an enterprise’s power supply system depends on the quality of electricity and the losses of the latter in electrical networks; both being largely determined by the modes of voltage control and reactive power compensation. In practice, the problems of voltage control and reactive power compensation in power supply systems of industrial enterprises, including electric networks with a voltage of up to 1 kV, as well as 6, 10 kV and higher, are often solved separately. It triggers an irrational use of existing voltage control devices, underutilization of the installed capacity of compensating devices, and affects the voltage control in the electrical networks of the power supply organization. Since voltage management and compensation modes of reactive power are inseparable, they can be correctly determined only with the use of an integrated approach based on technical and economic criteria and taking into account technical requirements and local conditions. This article analyzes the mutual influence of voltage control and reactive power compensation modes in the electrical networks of industrial enterprises from the point of view of ensuring the quality of electricity and minimizing load power losses. The method and results of calculations (on the example of a specific industrial facility) for determining voltage deviations and losses in the electrical network as well as for selecting parameters for voltage control and reactive power compensation are presented. Due to the close relationship of these modes that affect all voltage levels, the effectiveness of measures cannot be ensured without the use of multifunctional devices for controlling the equipment of transformer substations.

scholarly journals Analysis of the Fluctuation of the Number of ISO 9001:2015 Certificates in the Republic of Croatia and Assessment of Satisfaction of Business Organisations Leadership with the Certificate

2020 ◽  
Vol 66 (4) ◽  
pp. 40-49
Author(s):  
Petar Vušković
Keyword(s):  
Global Economy ◽  
Empirical Studies ◽  
Quality Standard ◽  
Iso 9001 ◽  
Annual Fluctuation ◽  
Level Of Satisfaction ◽  
The World ◽  
The Republic ◽  
High Level

AbstractThe ISO 9001:2015 certificate of quality is nowadays the most renowned quality standard in the world. Standardised quality has become an imperative competitive advantage on the market for all serious business organisations. The fluctuation of the number of certificates of quality indicates to what extent companies are willing to ensure the quality of their products and services to customers and clients, and how fast the domestic market is standardised and integrated into the global economy. This paper presents the results of two empirical studies. The first one focused on the analysis of the fluctuation in the number of ISO 9001:2015 certificates in the period from 2008 to 2018, while the second aimed to determine the satisfaction of leadership with the certificate. The study has shown that, during the observed period, the number of certificates of quality in Croatia fluctuated between – 18% and +22% annually. At the annual level, a certain number of companies lose their certificates or opt for decertification. For that reason, a study of the leadership’s level of satisfaction with the ISO 9001:2015 certificate was conducted using a sample of 296 certified business organisations. The study has proven that the leadership showed a high level of satisfaction with the certificate of quality and that they appreciate business organisations with certificates of quality. It demonstrates that the quality management certification has a bright future regardless of the annual fluctuation of the number of certificates.

scholarly journals Development of Optimum Repair Schedule of Electrical Network Equipment to Improve the Reliability of its Functioning

2019 ◽  
pp. 4-11
Author(s):  
Sergey V. Belyaev ◽  
Aleksey V. Malafeev ◽  
Evgeniy Ya. Omelchenko
Keyword(s):  
Power Supply ◽  
Technical Condition ◽  
Electrical Network ◽  
Steady Increase ◽  
Electrical Networks ◽  
Number Of Factors ◽  
Network Equipment ◽  
Long Time ◽  
Planning Algorithm ◽  
Labor Resources

To ensure uninterrupted power supply to consumers, maintenance of the electrical networks in a working condition is today carried out through the use of a system of preventive maintenance. In the general case such a system allows building equipment repair schedules based on repair cycles for a long time predetermining the list of necessary material and labor resources in advance. However, in practice, the use of this system is rather difficult and not always effective. This is due to the need to change the repair schedule for emergency or urgent repairs taking into account the seasonality of work performed and the organizational structure of the production department of electrical networks and related departments as well as taking into account the specific features of the operation of specific equipment. Taking into account the current pace of development of electrical networks with a steady increase in the number of consumers (which also leads to a complication of the configuration of electrical networks) this is impossible without the use of appropriate mathematics and software that automates the planning processes for the maintenance and repair of electrical networks with a large number of factors. The minimum equipment downtime was taken as the main criterion for optimality, as a factor that largely determines the reliability of power supply. A planning algorithm has been developed that takes into account the ranking of works in order of importance, the possibility of their shift in time and the likely adjustment of the schedule based on the results of assessing the technical condition of the equipment. A method for minimizing the downtime of repair crews by using them in adjacent areas as well as a technique for identifying a set of equipment that may be under repair in the same period of time are proposed.

scholarly journals Timely determination of static stability margins in power supply systems equipped with distributed generation installations

2021 ◽  
Vol 25 (1) ◽  
pp. 31-43
Author(s):  
Yu. N. Bulatov ◽  
A. V. Kryukov ◽  
К. V. Suslov ◽  
A. V. Cherepanov
Keyword(s):  
Distributed Generation ◽  
Power Supply ◽  
Computer Modelling ◽  
Dynamic Modelling ◽  
Electrical Network ◽  
Electrical Networks ◽  
Stability Margins ◽  
Emergency Control ◽  
Supply Systems

The article aims to develop a methodology to ensure timely determination of the margins of static aperiodic stability in power supply systems, at the nodal points of which distributed generation units are installed. The authors used mathematical methods and algorithms based on the application of limiting regime equations. Transitional processes were analysed for various points in the space of controlled mode parameters according to the simulation modelling in Matlab using the Simulink and SimPowerSystems packages. On the basis of the obtained results, an effective technique for analysing stability margins in electrical networks with distributed generation units was implemented. This method is applicable in design problems, as well as in operational and emergency control. The conducted theoretical analysis and computer modelling showed the effectiveness of the proposed methodology for calculating stability margins; the nondegeneracy of the Jacobi matrix of limiting regime equations at the solution point ensures the guaranteed reliability of the results. It was shown that an alternative approach to solving the problem of timely determination of aperiodic stability margins can be implemented on the basis of limiting regime equation with increased nonlinearity. Dynamic modelling of an electrical network with distributed generation units confirmed the correctness of determining the stability margins calculated using limiting regime equations. The developed technique can be recommended for practical use in the design of power supply systems or in operational control of synchronous generators. In particular, the presented methodology can be used to implement a multi-agent emergency control system for distributed generation installations located in generalpurpose distribution electrical networks. 

scholarly journals AUTOMATED WORKPLACE OF THE ELECTRICAL NETWORK DISPATCHER

2019 ◽  
pp. 23-29
Author(s):  
Shamil Abbasovich Turpishchev ◽  
Andrey Vladimirovich Rogov ◽  
Alexey Vladimirovich Anikeev ◽  
Sergey Vladimirovich Golovko
Keyword(s):  
Management System ◽  
Electrical Energy ◽  
Information Management System ◽  
Power Industry ◽  
Basic Function ◽  
Normal Operation ◽  
Electrical Network ◽  
Technological Equipment ◽  
Electrical Networks ◽  
Monitoring And Control

Currently, a great number of organizations are seeking to automate the workflow and to use electronic information. The article considers a method to increase reliable and economic distribution of electrical energy by means of supporting highly effective operational and technological activities of distribution power grid companies, by complex automation of collecting, processing, transferring information and making decision on executing a basic function of operational and technological control. The main problems of transforming technological equipment and electrical networks into a single information management system of the dispatcher monitoring have been considered. According to the Federal Law “On power industry”, the purpose of the system of supervisory control in power industry is to support the reliable power supply and quality of electrical energy that correspond to the requirements of technical rules and requirements, as well as other regulations set by organizational and distributive acts. In order to achieve the goals there is developing the in-house network management system integrated into the general hierarchical structure, which increases its efficiency. The interaction of subjects of a power facility is defined by the needs of operational and technological monitoring and control for power engineering. Using the automated software system will reduce electricity shortage, prevent failures in the normal operation of the power system and improve its reliability due to the completeness of information on technological equipment operation.

scholarly journals QUALITY OF BANKING PRODUCTS: FACTORS OF INFLUENCE

2021 ◽  
Author(s):  
Tetiana Gavrilko ◽  
Karina Skripnik
Keyword(s):  
Customer Orientation ◽  
Banking System ◽  
Modern World ◽  
Quality Level ◽  
Factors Influencing ◽  
The World ◽  
Oriented Activity ◽  
The Impact

The article presents the impact on the quality of banking products of internal and external factors in terms of the need to strengthen the customer orientation of banking activities based on innovative technological decisions. The state of the banking system of Ukraine in a pandemic is analysed and the necessity of banks to find new opportunities to ensure a high level of quality of their products, both traditional and innovative, taking into account the peculiarities of modern world trends. The essence of the concepts "banking product" and "quality of a banking product" is studied. The expediency of considering the complex of concepts - a banking product, a banking service and a banking operation - as a set of interrelated elements that constitute a certain holistic hierarchical system was determined. The article substantiates the necessity of understanding the quality of a banking product as the degree of satisfaction of clients' needs taking into account a number of criteria that form a state of loyalty to the banking institution, ensuring its sustainable operation in the short and long term. The basic principles to which the portfolio of banking products should correspond are highlighted. External and internal factors influencing the quality of the banking products portfolio are analysed. The role of organizational culture of the bank as the basis for strengthening client-oriented activity has been defined. The factors which influence the level of loyalty of the banking institution's clients have been studied. The main differences between the priorities of customers and banks are considered. The focus is placed on the need for hyper-personalization when interacting with customers, which will allow them to best meet their needs by providing relevant services. The prospects of cooperation between banks and Fintech companies as a condition for creating modern innovative products on the basis of providing the appearance of a synergistic effect of a new quality level were analysed. This cooperation will open the possibility of access to a solid bank customer audience for Fintech companies, and for others it is a condition for mastering of modern digital innovations. The factors influencing the level of development of the Fintech industry are considered, and the dominant trends in the field of digitalization of the leading countries of the world are given. The role of neobanks in creating conditions for a high quality of interaction with consumers as compared with classic banks was investigated. The features in the activities of the leading non-banks of the world are set out. The reality of the threat to banking systems from technological giants BigTech was analysed. Identified changes in the needs of customers to obtain a set of financial and non-financial products. Considered the possibility of meeting customer needs by forming a banking ecosystem with access to other, non-traditional banking segments.

scholarly journals КОМПЛЕКСНЕ ОЦІНЮВАННЯ ЕФЕКТИВНОСТІ ВСТАНОВЛЕННЯ ДОДАТКОВИХ ДЖЕРЕЛ РЕАКТИВНОЇ ПОТУЖНОСТІ У РОЗПОДІЛЬНИХ ЕЛЕКТРИЧНИХ МЕРЕЖАХ

2018 ◽  
Vol 124 (4) ◽  
pp. 103-111
Author(s):  
В. В. Кулик ◽  
О. Б. Бурикін ◽  
В. М. Пірняк
Keyword(s):  
Reactive Power ◽  
Comprehensive Evaluation ◽  
Efficiency Index ◽  
Electrical Network ◽  
Electrical Networks ◽  
Power Sources ◽  
Search Area ◽  
Electrical Grids ◽  
Monitoring Devices

To develop a method for assessing the effectiveness of reactive power sources (RPS) in electrical grids. The efficiency indicator was obtained as a result of combining the method of assessing the quality of the functioning of electrical grids on the basis of Markov networks and the method of interval analysis of energy losses. The efficiency index improves the formulation of the problem of optimizing the connection of the RPS to electrical networks. It improves the quality of this task. A new method of forming an indicator of the guaranteed effectiveness of the installing the RPS is obtained. It provides an unambiguous comprehensive evaluation of efficiency, takes into account the reliability of the electrical network, the quality of the voltage in its nodes, the accuracy of calculating the released and lost electricity. The method makes it possible to construct more efficient algorithms for optimizing the connection of RPS. They allow excluding from the search area optimal solutions "indefinite" fragments of the network without the help of an analyst. Estimation of the real effect is difficult or impossible for such fragments due to frequent failures or lack of monitoring devices. This correction of the search area improves the quality of the solution.

Мodel for detecting and evaluating the fire hazard of spark discharges in the electrical networks of passenger cars based on the use of fiber- optic sensors

2021 ◽  
pp. 46-51
Author(s):  
Vladislav Andreevich Khanis ◽  
◽  
Sergey Valeryevich Bespalko ◽  
Igor Alexeevich Klyuchikov ◽  
Andrey Leonidovich Khanis ◽  
...  
Keyword(s):  
Fiber Optic ◽  
Fire Hazard ◽  
Fiber Optic Sensors ◽  
Electrical Contacts ◽  
Electrical Network ◽  
Rolling Stock ◽  
Electrical Networks ◽  
Passenger Cars ◽  
Spark Discharges ◽  
Optical Flashes

The paper substantiates an approach to assessing the fire hazard of spark discharges in the electrical equipment elements of passenger cars of rolling stock based on the detection of optical flashes using fiber-optic sensors. The presented numerical model makes it possible to realize the possibility of detecting and evaluating optical flashes of weak spark discharges on potentially fire-hazardous electrical contacts in the electrical networks of passenger cars. To solve this problem, it seems appropriate to place sensors of electrical discharges using optical fibers to deliver to them the radiation of optical flashes of spark discharges from fire-hazardous spatially remote elements of the electrical network.

Mobile Measuring Complex for Conducting an Electric Network Survey

2020 ◽  
pp. 243-267 ◽  
Author(s):  
Alexander Vinogradov ◽  
Vadim Bolshev ◽  
Alina Vinogradova ◽  
Maxim Borodin ◽  
Alexey Bukreev ◽  
...  
Keyword(s):  
Electrical Network ◽  
Electrical Networks ◽  
Energy Audit ◽  
Power Networks ◽  
Operating Modes ◽  
Electric Transmission ◽  
Measuring Complex ◽  
Electric Transmission Line ◽  
Required Quality

An energy audit of the electrical network is required in the process of constructing new electrical networks as well as in justifying the reconstruction need of existing ones. In this chapter, the structure of a mobile measuring complex has been developed to conduct an electrical network survey without disconnecting consumers. The complex can be used to inspect 0.4 kV electrical networks and microgrids of the same voltage class and allows data collection on voltage losses and electric power losses in network elements such as a power lines (electric transmission line), and power transformers. The energy audit is conducted without disconnecting consumers in order to avoid an undersupply of electricity as well as to determine the real operating modes of power networks. Ultimately, the use of the developed measuring complex will increase the reliability of the power supply to consumers and ensure the required quality of the electricity supplied to them.

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