21 августа 2020
«ЭЛЕКТРОЭНЕРГИЯ. Передача и распределение» № 4(61), июль-август 2020
РЕЛЕЙНАЯ ЗАЩИТА И АВТОМАТИКА
ДИАГНОСТИКА И МОНИТОРИНГ
ДИАГНОСТИКА И МОНИТОРИНГ
An aspect of developing the work schedule of technical inspection of power transit measurement intended for selection of power measurement points subject to first-priority inspection is the topic of this article. The mathematic model of work scheduling of power transit measurement technical inspection has been formalized based on assessment of capabilities and consequences of the off-the-meter power consumption and available operating (labor) resources of a grid company. The proposed procedure enables definition of priority and the type of technical inspection (instrumental tests, visual inspections, recording) in respect to all measurement points within the maintenance area of agrid company. A local power distribution zone has been taken for defining power measurement points subject to first-priority inspection and all points have been distributed by inspection types.
grid company, power measurement, measuring system checks, power consumers, commercial power losses, power measurement point ranking
A two-stage methodology to justify the effectiveness of an interstate power grid as a whole and for the separate countries-participants is proposed. In this case, an optimization mathematical model of thepower system expansion and economic dispatching is used. The results of a study of the effectiveness ofprospective power grid in Northeast Asia with participation of countries of the region, including Russia, are presented.
interstate electric ties and power grids, electric power systems, generating capacity, transfer capacities, integration system benefits, cost
The article is devoted to the problems of research of the electric power systems operation and development taking account energy security requirements. The schemes of indicative and model approaches to research are given. Energy security indicators which meet the requirements of the Russia’s Energy Security Doctrine are presented to assess the situation at the electric power systems.
electric power system, energy security, indicators, modelling
The suggested paper describes a technique for optimization of fuel supply to power plants and presents a list of factors which can affect conditions of fuel supply to power plants in one way or another. The suggested technique is based on the dynamic optimization model of the national energy sector (in the context of federal districts) that makes it possible to take into consideration the territorial and technological structure of production and consumption of primary energy resources, electric power, district heat, furnace fuel. Alist of problems that are solved in the block of electric and thermal power industries in the energy sector model is presented. An example of assessing the impact of limitations on СО2 emissions by thermal power plants on the innovation development of Russia’s energy sector and conditions of their fuel supply inthe long term is described.
thermal power plants, conditions of fuel supply, optimization technique, limitations on СО2 emissions, innovation technologies
OVERHEAD TRANSMISSION LINES
Various types of voltage transformers (VT) are used in AC electric power systems for transmitting the signal of measurement information to measuring, protection, automation, signaling and control devices. When ice is melted on overhead power lines with direct current, a constant voltage is applied to the primary windings of the VTs included in the ice melting circuit. In electromagnetic VTs, the direct current of the primary windings, limited only by their active resistance, can lead to damage to the VTs. To prevent this, theVT must be switched off during assembly of the ice melting scheme or the capacitors must be constantly switched on in the primary winding circuit. The article proposes the division of VTs connected to the ice melting circuit with direct current into three categories: they do not require shutdown; do not require shutdown when installing capacitors; must be disabled. The separation technique uses technical data from passports and test reports of specific VTs, as well as the constant voltage values for VTs given in thesummary table in the main ice melting schemes.
voltage transformer, overhead power line, DC ice melting scheme
In terms of lightning protection the illumination network is peculiar for its long distance and low insulation resistance. Its functionality involves matters of security and commercial efficiency of companies. In this article an attempt to develop the procedure of justifying the surge protection device application for protection of illumination network against lightning surges has been made. The cost-and-saving calculation based on assessment of risks concerned with equipment damage should be taken as a basis for solving this task.
surge protection device, direct lightning strike, illumination network
RELAY PROTECTION AND AUTOMATION
Relay protection and automation devices have not only protection functions, but also additional ones, such as fault detection, recording of emergency oscillograms, monitoring of network parameters, etc., by manufacturers, unlike predecessors microprocessor terminals have high accuracy in setting protection parameters. But despite this, the relay protection device can still operate “falsely”, or “unnecessarily” or “not”. The reason for this behavior of the microprocessor terminals is not to take into account the external factors affecting in, therefore, under certain conditions the error can exceed the rated 5% value calculated only for normal weather conditions.
relay protection, the response factor of the microprocessor terminals, adaptive setting
DIAGNOSTICS AND MONITORING
The problem of ensuring the reliability of analytical control in an emergency, consisting in the drawbacks of the common sampling systems for gas in gas relay, is presented. The newest sampling systems with flexible shell are proposed. The newly-developed methodology for assessing the impermeability of gastight sampling systems with a flexible shell is presented. The structure of a specially designed adapter for dosing and direct injection of the sample into the chromatographic complex is described. The results of aspecial experiment to evaluate the metrological characteristics of the developed method are presented, onthe basis of which a quantitative criterion for assessing the suitability of gas-tight packs for the selection and storage of gas samples is determined.
method, analysis, analytical control, sampling system, sample
In recent years, the most significant causes of industrial injuries for repair and maintenance personnel are organizational and psychophysiological reasons, but there is no unified approach to reducing the impact of the latter in our country. The paper analyses the main groups of methods for assessing professional qualities and stress tolerance of employees, identifies their advantages and disadvantages, and suggests the most promising approaches to taking into account the individual characteristics of employees. Based on statistical data, the analysis of the impact on the injuries level of the main employees psychophysiological characteristics is carried out. The ranges of age and length of service of employees with a high risk of injury for the electric power industry have been determined.
labor protection, industrial safety, accident, injuries, psychophysiological features, age, experience