Electrical Network Modeling and Electrical Transfer Simulation of C.N. Asco´ I and C.N. Asco´ II, to Obtain Voltage and Frequency Limit Values Allowing the Electrical Transfer From the Main Generator to the External 110 kV Power Grid

2009 ◽  
Author(s):  
Alberto Ban˜o´ Azco´n ◽  
Jose´ Mollera Barriga
Keyword(s):  
Power Supply ◽  
Power Grid ◽  
Circuit Breaker ◽  
Operating Mode ◽  
Electrical Network ◽  
Limit Values ◽  
Electric System ◽  
Future Design ◽  
Turbo Generator ◽  
Protective Relays

Broadly speaking, a simple electrical diagram of Asco´ I and Asco´ II power nuclear plants could be two power supply bus bars for general equipment classified No-1E, three power supply bus bars class No-1E for the Reactor Coolant Pumps (RCP) and two more bus bars classified 1E for safety related equipment. In normal operating mode, all the five power supply bus bars class No-1E are connected to the main generator (GP1) through two unit transformers (TAG1/2), while the two class 1E power supply bus bars are always connected to an external 110 kV power grid through two auxiliary transformer (TAA1/2). The main generator supplies power to an external 400 kV grid through the main transformer (TP1). The main circuit breaker is placed between the high voltage side of the main transformer and the 400 kV grid. With this configuration, the appearance of an abnormal condition that originates the trip of the main generator and the opening of the main circuit breaker from the external network, involves an electric transfer of the supply bus bars connected to the turbo generator to the external 110 kV power grid. The electric transfer to the external 110 kV power grid will be only possible if the frequency and voltage values are within the allowed range allowed by the grid’s protective relays. Two kinds of electrical transfers are possible: fast transfers and slow transfers. It will be necessary then to evaluate the limit values of voltage and frequency of the power grid that makes the electrical transfer possible in each case. In order to obtain the limit values previously mentioned, the electric system of the plant has been modeled. Different scenarios have been analyzed, taking into account the dynamic behavior of the system components and the delay of the protective relays actuation, verifying the electrical transfer for those situations. This analysis will give enough information to take the correct decisions for future design modifications, and it will assure that the electrical transfer will be done always with success.

scholarly journals ANALYSIS OF INFORMATION CONDITIONS OF FORMATION OF STRUCTURAL-LOGICAL MODEL OF EMERGENCY MANAGEMENT IN THE CONDITIONS OF ABSENCE

2020 ◽  
Vol 4 (157) ◽  
pp. 97-102
Author(s):  
T. Vovchuk ◽  
N. Deyneko ◽  
О. Levterov ◽  
R. Shevchenko
Keyword(s):  
Emergency Response ◽  
Power Supply ◽  
Power Grid ◽  
Mechanical Damage ◽  
Emergency Situation ◽  
Rechargeable Batteries ◽  
Electrical Network ◽  
Electric Networks ◽  
Response Systems ◽  
Emergency Response Systems

The paper considers the problem of accidental destruction of power lines due to external factors, which led to the de-energization of large areas for a long time. Breakdowns can be caused by both mechanical damage and natural disasters - floods and earthquakes and more. As a rule, as a result of an emergency situation, the level of energy supply of large areas decreases. An important methodological aspect in studying the quality of the electrical network is the allocation of hierarchical levels of consideration. Thus, the authors consider the lowest level of functioning of the electrical network, namely the power supply of the emergency response system. Such circumstances, in turn, can lead to the emergence and development of emergencies that lead to significant casualties and destruction. It has been established that some accidents have led to power outages for more than one day. The analysis of features of work of emergency counteraction systems which are used on objects in the conditions of damage of electric networks is carried out. Devices of emergency counteraction of domestic production which have found wide application on objects and continue to be improved and let out are considered in work. Approaches to the use of imported emergency response devices, in terms of operation and installation, are almost the same, as they must meet the requirements of those regulations that are used in Ukraine. It is established that redundancy of power supply of such systems at the expense of rechargeable batteries allows to carry out their uninterrupted work no more than 24 hours. That is, if the power supply of emergency response systems from the traditional power supply network is not restored within 24 hours, such systems will stop working, which may lead to an emergency becoming an emergency. Thus, the further work of the authors will be aimed at finding a way to back up emergency response systems in the event of a power outage from the traditional power grid for a time exceeding the possibility of power supply from the battery. Keywords: emergency destruction, emergency, power grid, emergency response systems, backup power supply.

New aspects of power grid facilities personnel workplaces electromagnetic environment

2020 ◽  
Vol 60 (9) ◽  
pp. 569-574
Author(s):  
Nina B. Rubtsova ◽  
Sergey Yu. Perov ◽  
Olga V. Belaya ◽  
Tatiana A. Konshina
Keyword(s):  
Transmission Lines ◽  
Power Transmission ◽  
Power Grid ◽  
Spectral Characteristics ◽  
Ground Level ◽  
Frequency Characteristics ◽  
Frequency Range ◽  
Electromagnetic Environment ◽  
Limit Values ◽  
Special Assessment

Introduction. Electromagnetic safety of power grid facilities staff requires the exclusion of electromagnetic fields (EMF) harmful effects. EMF is evaluated by 50 Hz electric and magnetic fields (EF and MF) values in the framework of working conditions special assessment, and very rarely the analysis of the electromagnetic environment (EME) is carried out in depth. The aim of the study - EME hygienic assessment of power grid EHV facilities personnel workplace with adequate 50 Hz EF and MF levels evaluation as well as the analysis of EF and MF in the frequency range from 5 Hz to 500 Hz amplitude-frequency characteristics. Materials and methods. 50 Hz EF and MF values assessment was carried out on open switchgears (S) of substations and within sanitary breaks of 500 and 750 kV overhead power transmission lines (OTL). Measurements along to OTL trasses was performed using matrix-based method. Measurements and analysis of EF and MF values in 5-500 Hz frequency range amplitude-frequency characteristics were performed in the territory of 500 and 750 kV S. Results. Power frequency 50 Hz measurements results at 500 and 750 kV S ground-level personnel workplaces showed the presence of an excess of permissible limit values by EF intensity and the absence of an excess by MF. The measured EF values within 500 and 750 kV OTL sanitary gaps require limiting the working time of linemen due to the excess of the hygienic norms for full work shift, while the MP levels were almost completely within the standard values for persons not occupationally connected with electrical installations maintenance. MF and EE frequency range from 50 Hz to 500 Hz spectral characteristics analysis showed that 3rd harmonic percentage does not exceed 2.5% for EF and 6% for MF of the main level, the level of the 5th harmonic does not exceed 1% for EF and 3.5% for MF, the level of the 7th harmonic does not exceed 0.2% for EF and 0.8% for MF. These data show despite its low levels the contribution of MF different harmonics in a possible adverse impact on humane than EF corresponding harmonics. Conclusions. There was the confirmation of the previously justified use of the "matrix" scheme for of EF and MF values measurement along OTL routes. The relevance of to EF and MF all frequency components expos ure assessing possible health risk in extremely high voltage S territories and under OTL, based on international recommendations due to the lack of sanitary regulations in the Russian Federation for >50 Hz-30 kHz EF and MF, is shown.

Justification for Unscheduled Maintenance of Solar Panels Used as a Power Supply for Sprinkler Machines

2020 ◽  
Vol 67 (1) ◽  
pp. 16-21
Author(s):  
Sergey M. Bakirov ◽  
Sergey S. Eliseev
Keyword(s):  
Power Supply ◽  
Power Loss ◽  
Renewable Energy Sources ◽  
Operating Mode ◽  
Dust Storms ◽  
Research Purpose ◽  
Solar Panels ◽  
Solar Module ◽  
Empirical Observation ◽  
Modern Level

The modern level of agriculture is described by the introduction of renewable energy sources. New generation sprinkler machines are being put into production, in the power system of which solar panels are used. One of the factors that negatively affect the performance of solar cells in an open field is their dusting, which is formed as a result of dust storms and wind. Cleaning of the battery panels is carried out in various ways: manual, semi-automatic and automatic. Dust cleaning is included in maintenance. (Research purpose) The research purpose is to determine the conditions for performing the maintenance, which consists in cleaning solar panels in the field. (Materials and methods) Theoretical (analysis, hypothesis design), empirical (observation, testing), experimental (ascertaining experiment) methods has been used during research. (Results and discussion) The article describes an introduced parameter for estimating the level of dusting. The power loss indicator shows the ratio of the power of the dusted module to the power of the clean module. Unscheduled maintenance is affected by the distance of the solar module from the repair point, the power of the solar module, the loss from dusting, the frequency of maintenance and cost indicators. (Conclusions) It has been found the dependence of maintenance period of the solar module of the sprinkler machine on the distance to the sprinkler machine, to the point of maintenance and repair, the power loss coefficient in case of dusting of the solar module, the cost of performing maintenance, as well as the frequency of maintenance. Article describes the boundaries of the choice of operating mode of the sprinkler between unscheduled maintenance for cleaning the solar module and the acceptance of additional power of the sprinkler power supply system according to the criterion of minimum operating costs.

Influence of distributed power supply in distributed power distribution network

2021 ◽  
pp. 1-8
Author(s):  
Xin Shen ◽  
Hongchun Shu ◽  
Min Cao ◽  
Nan Pan ◽  
Junbin Qian
Keyword(s):  
Power Supply ◽  
Power Distribution ◽  
Short Circuit ◽  
Power Grid ◽  
Distribution Network ◽  
Distribution Networks ◽  
Power Supplies ◽  
Power Distribution Network ◽  
Power Sources ◽  
Distributed Power

In distribution networks with distributed power supplies, distributed power supplies can also be used as backup power sources to support the grid. If a distribution network contains multiple distributed power sources, the distribution network becomes a complex power grid with multiple power supplies. When a short-circuit fault occurs at a certain point on the power distribution network, the size, direction and duration of the short-circuit current are no longer single due to the existence of distributed power, and will vary with the location and capacity of the distributed power supply system. The change, in turn, affects the current in the grid, resulting in the generation and propagation of additional current. This power grid of power electronics will cause problems such as excessive standard mis-operation, abnormal heating of the converter and component burnout, and communication system failure. It is of great and practical significance to study the influence of distributed power in distributed power distribution networks.

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

scholarly journals Universal microprocessor controlled power regulator with and without additional power supply

2020 ◽  
Vol 33 (1) ◽  
pp. 83-104
Author(s):  
Vladan Vuckovic ◽  
Blond Le
Keyword(s):  
Power Supply ◽  
Power Grid ◽  
Alternating Current ◽  
Resistive Load ◽  
Resistive Heating ◽  
Complex Control ◽  
Power Regulator ◽  
Touch Sensor ◽  
Advanced Technologies ◽  
Reconstruction Project

Inexpensive microcontrollers allow complex control methodologies for improving well-established technologies such as resistive lighting. In this paper, we present two constructions of a microprocessor controlled power regulator for resistive load of up to 2.5 kW and exemplify its use for the lamps in Tesla?s Fountain reconstruction project. These are universal power controllers and could be applied to a wide verity of non-inductive loads, but our primary intention was to construct a miniature light regulator with touch sensor for Tesla?s Fountain. The devices operate using the phase control of the power grid?s alternating current and controlled fade-in to increase lamp longevity. Extensive testing shows the device to operate successfully for 2400 hours of continuous error-free operation, to robustly handle high cycling stresses and increase bulb lifetimes by approximately a factor of 7-8. The microcontroller software can easily be adapted for controlling many non-inductive apparatus, like light bulbs or halogen lamps, as well as resistive heating. We also used advanced technologies from other multi-disciplinary areas to complete project.

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.

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