scholarly journals Research of higher harmonic components of voltage and current and their influence on the functioning of shipboard electrical equipment

2021 ◽  
pp. 34-43
Author(s):  
В.Ф. Белей ◽  
Г.А. Решетников ◽  
К.В. Коротких
Keyword(s):  
Experimental Studies ◽  
Electrical Energy ◽  
Electrical Equipment ◽  
Electrical Network ◽  
Electric Motors ◽  
Electrical Networks ◽  
Higher Harmonic ◽  
Harmonic Components ◽  
Quality Of Electrical Energy ◽  
Asynchronous Electric Motors

Одним из направлений научно-технического прогресса на объектах морской индустрии является широкое использование технологий, основанных на нелинейных элементах, что позволяет значительно снизить их массогабаритные показатели и расшить их функциональные возможности. Однако применение таких технологий приводит к ухудшению качества электрической энергии, в первую очередь за счет высших гармонических составляющих напряжения и тока. В статье показана природа высших гармонических, выполнен анализ разделов «Правил классификации и постройки морских судов. 2021», российских и ряда зарубежных стандартов в области качества электроэнергии, регламентирующих уровень высших гармонических составляющих напряжения и тока в электрических сетях и системах. В работе приведены результаты теоретических и экспериментальных исследований влияния высших гармонических составляющих на функционирование судового электрооборудования: асинхронных электродвигателей, силовых кабелей, трансформаторов, конденсаторных батарей и систем освещения. Определены выражения, позволяющие оценить это влияние. Показано, что в основном это влияние проявляется: в дополнительном нагреве электрооборудования за счет поверхностного эффекта; вибрации асинхронных электродвигателей при высоких значениях 5 и 7 гармоник напряжения судовой электрической сети. One of the areas of scientific and technological progress at the facilities of the marine industry is the widespread use of technologies based on nonlinear elements, which can significantly reduce their weight-size parameters and dimensions and expand their functional capabilities. However, the use of such technologies leads to a deterioration in the quality of electrical energy, primarily due to higher harmonic components of voltage and current. The article shows the nature of higher harmonics, analyzes the sections of the «Rules for the Classification and Construction of Sea-Going Vessels. 2021», Russian and a number of foreign standards in the field of electric power quality, regulating the level of higher harmonic components of voltage and current in electrical networks and systems. The paper presents the results of theoretical and experimental studies of the influence of higher harmonic components on the functioning of shipboard electrical equipment: asynchronous electric motors, power cables, transformers, capacitor banks and lighting systems. Formulas have been determined to assess this effect. It is shown that the influence is mainly manifested: in additional heating of electrical equipment due to the skin effect; vibrations of asynchronous electric motors at high values of 5th and 7th voltage harmonics of the ship's electrical network.

scholarly journals ANALYSIS OF VOLTAGE NON-SINUSIDALITY IN POWER SUPPLY SYSTEMS WITH INDUCTION HEATING UNITS

2021 ◽  
pp. 122-133
Author(s):  
Dmitriy Yu. Rudi ◽  
Sergey V. Gorelov ◽  
Aleksandr I. Antonov ◽  
Mikhail G. Vishnyagov ◽  
Aleksandr A. Ruppel
Keyword(s):  
Electromagnetic Interference ◽  
High Performance ◽  
Low Frequency ◽  
Electrical Energy ◽  
Electrical Network ◽  
Electrical Networks ◽  
Harmonic Voltage ◽  
Harmonic Components ◽  
Quality Of Electrical Energy

The importance of the problem of improving the quality of electrical energy grew along with the development and widespread introduction of various high-performance technological installations in production, such as arc steel-making furnaces, welding installations, induction furnaces, etc. in accordance with the requirements of the standard GOST 30804.4.7–2013 and in accordance with the measurement program. A method for processing the research results obtained during the experiment is described. All power quality indicators are processed using computer programs created in the Labview graphical programming environment. The analysis of indicators of the quality of electrical energy to the requirements of GOST 32144-2013 was carried out, according to the results of which conductive low-frequency electromagnetic interference was detected in the 0.4 kV electrical network according to the coefficient of the n-th harmonic voltage components. The obtained values ​​of the indicators of the quality of electrical energy, characterizing the coefficient of the n-th harmonic components of the voltage, confirm the need to use technical means to reduce the influence of higher harmonics on electrical networks.

scholarly journals Improving the functioning efficiency of 6-10 kV electrical networks with isolated neutral in conditions of single-phase ground faults

2021 ◽  
Vol 288 ◽  
pp. 01010
Author(s):  
Alexander Nikolaevich Kachanov ◽  
Vadim Alekseevich Chernyshov ◽  
Boris Nikolaevich Meshkov ◽  
Marsel Sharifyanovich Garifullin ◽  
Evgeny Alexandrovich Pechagin
Keyword(s):  
Single Phase ◽  
Climatic Factors ◽  
Experimental Studies ◽  
Electrical Energy ◽  
Distribution Networks ◽  
Electrical Network ◽  
Electrical Safety ◽  
Electrical Networks ◽  
Isolated Neutral ◽  
Remote Identification

The main objectives of this publication are: 1) to attract the attention of energy specialists to the problems of reliability and electrical safety of 6-10 kV overhead electrical networks with isolated neutral, operating in conditions of single-phase insulation damage; 2) substantiation of the feasibility of introducing a fundamentally new way to improve the efficiency of 6-10 kV distribution networks, based on the resonanceless limitation of the single-phase ground fault current arising from the breakdown of the insulator and the use of its own infrastructure of the electrical network for remote identification of the place of its occurrence. The expediency of including a nonlinear surge suppressor between the traverse and the grounding outlet of the reinforced concrete support is confirmed by the positive results of experimental studies carried out on the basis of high-voltage testing laboratories of IDGC of Center PJSC - Orelenergo and EnerGarant LLC. The use of deductive analysis allowed the authors to select a reliable and affordable electrical insulating material installed between the support and the traverse, as well as to formulate the main requirements for it, including taking into account weather and climatic factors. The analysis of various methods of transmitting information about the place of occurrence of the insulator damage made it possible to establish the predominant advantage of a wired communication channel using its own 6-10 kV electric network infrastructure. The authors have developed an original circuitry solution that provides remote identification of the insulator damage location using a thyristor shunting the nonlinear surge suppressor, according to a given switching algorithm, and also provides local identification of the insulator breakdown by means of special signaling devices with volatile power supply. It is expected that the proposed method, with relatively low investment, will significantly reduce the level of accidents and electrical hazards in overhead distribution networks of 6-10 kV, as well as minimize the costs associated with their operation and undersupply of electrical energy.

ELECTROMAGNETIC COMPATIBILITY OF LOW-POWER AUTONOMOUS POWER SUPPLY EQUIPMENT

2020 ◽  
Author(s):  
V.N. Delyagin ◽  
◽  
V.I. Bocharov ◽  
Keyword(s):  
Low Power ◽  
Power Supply ◽  
Electromagnetic Compatibility ◽  
Autonomous Systems ◽  
Electric Energy ◽  
Electrical Energy ◽  
Electrical Equipment ◽  
Electrical Network ◽  
Nonlinear Load ◽  
Harmonic Components

The article presents the results of research on the evaluation of electromagnetic compatibility of elements of the power supply system for Autonomous low-power consumers. The subject of the study is a quantitative assessment of the level of harmonic components of currents and voltages in systems: a permanent magnet generator-a DC-to-AC Converter-a consumer with a nonlinear load and interfering interaction of jointly working elements of this system. The level of harmonics of voltage and current in the local electrical network (farm), repeatedly (from 3 to 10 times) exceeds the regulatory requirements. The multiplicity of the increase in electrical energy losses (K-Factor) is from 5("pure" sine of the DC-AC Converter) to 20 (rectangular meander). When designing Autonomous systems, it is necessary to provide measures to reduce the loss of electrical energy, exit from standing electrical equipment and false triggering of electronic devices in the consumer of electric energy

scholarly journals Predicting the influence of the non-sinusoidal network mode on power transformers

2019 ◽  
Vol 114 ◽  
pp. 04005
Author(s):  
Ngo Van Cuong ◽  
Lidiia I. Kovernikova
Keyword(s):  
Service Life ◽  
Electric Power ◽  
Power Quality ◽  
Electrical Equipment ◽  
Operating Conditions ◽  
Transformer Oil ◽  
Power Transformers ◽  
Electrical Network ◽  
Electrical Networks ◽  
Current Harmonics

The parameters of electrical network modes often do not meet the requirements of Russian GOST 32144-2013 and the guidelines of Vietnam. In the actual operating conditions while there is the non-sinusoidal mode in electrical networks voltage and current harmonics are present. Harmonics result in overheating and damage of power transformers since they cause additional active power losses. Additional losses lead to the additional heat release, accelerating the process of insulating paper, transformer oil and magnetic structure deterioration consequently shortening the service life of a power transformer. In this regard there arises a need to develop certain scientific methods that would help demonstrate that low power quality, for instance could lead to a decrease in the electrical equipment service life. Currently we see a development of automated systems for continuous monitoring of power quality indices and mode parameters of electrical networks. These systems could be supplemented by characteristics calculating programs that give out a warning upon detection of the adverse influence of voltage and current harmonics on various electrical equipment of both electric power providers and electric power consumers. A software program presented in the article may be used to predict the influence of voltage and current harmonics on power transformers.

scholarly journals Calculations, norming and reducing of electrical energy losses in city electrical networks

2019 ◽  
Vol 21 (3) ◽  
pp. 46-54
Author(s):  
A. V. Lykin ◽  
E. A. Utkin
Keyword(s):  
High Voltage ◽  
Power Transmission ◽  
Low Voltage ◽  
Demand Curve ◽  
Electrical Energy ◽  
Electrical Network ◽  
Energy Losses ◽  
Capital Investments ◽  
Electrical Networks

The article considers the feasibility of changing the structure of a distribution electrical network by transferring points of electricity transformation as close to consumers as possible. This approach is based on installation of pole-mounted transformer substations (PMTS) near consumer groups and changes the topology of the electrical network. At the same time, for groups of consumers, the configuration of sections of the low-voltage network, including service drops, changes. The efficiency of approaching transformer substations to consumers was estimated by the reduction in electrical energy losses due to the expansion of the high-voltage network. The calculation of electrical losses was carried out according to twenty-four hour consumer demand curve. To estimate the power losses in each section of the electrical network of high and low voltage, the calculated expressions were obtained. For the considered example, the electrical energy losses in the whole network with a modified topology is reduced by about two times, while in a high-voltage network with the same transmitted power, the losses are reduced to a practically insignificant level, and in installed PMTS transformers they increase mainly due to the rise in total idle losses. The payback period of additional capital investments in option with modified topology will be significantly greater if payback is assessed only by saving losses cost. Consequently, the determination of the feasibility of applying this approach should be carried out taking into account such factors as increasing the reliability of electricity supply, improving the quality of electricity, and increasing the power transmission capacity of the main part of electrical network.

scholarly journals Evaluation of the Influence of Non-sinusoidal Conditions on Power Transformers

2018 ◽  
Vol 58 ◽  
pp. 03012
Author(s):  
Lidiia Kovernikova ◽  
Ngo Van Cuong
Keyword(s):  
Cost Effective ◽  
Electrical Equipment ◽  
Power Transformers ◽  
Electrical Network ◽  
Operating Parameters ◽  
Electrical Networks ◽  
Equipment Operation ◽  
Traction Substation ◽  
Operation Conditions ◽  
Railway Traction

The electrical equipment operation is cost-effective and reliable when operating parameters of the electrical network correspond to the rated data of the equipment. The real operation conditions, however, differ from those required for electrical equipment, which negatively affects its efficiency. The non-sinusoidal conditions in electrical networks are currently very common. The paper provides an overview of the characteristics obtained from an analysis of publications, which are used to evaluate the effect of the non-sinusoidal conditions on power transformers. The results of the calculation of these characteristics for a transformer installed at a railway traction substation are presented. Parameters of the non-sinusoidal conditions are obtained as a result of measurements.

scholarly journals Advanced power transformer with improved parameters for rural electrical networks

2021 ◽  
Vol 59 (3) ◽  
pp. 366-377
Author(s):  
M. A. Prishchepov ◽  
A. I. Zelenkevich ◽  
V. M. Zbrodyga
Keyword(s):  
Power Supply System ◽  
Single Phase ◽  
Power Transformer ◽  
Electrical Equipment ◽  
Electrical Networks ◽  
Power Losses ◽  
Linear Load ◽  
Non Linear ◽  
Harmonic Components ◽  
Non Linear Load

The problem of power quality supply is relevant for rural electrical networks, due to long distance and branching, as well as connection of a large number of single-phase and non-linear loads. Asymmetry of electrical loads causes voltage asymmetry, which adversely affects the operation of all elements of the electrical system, causing additional power losses, reducing the service life of electrical equipment and its economic performance, as well as reliability of operation of individual electrical equipment and power supply system as a whole. Reduction of voltage asymmetry can be ensured by rational construction of electrical network circuit and use of special correcting devices. The authors consider it reasonable to use relatively simple and reliable by design and inexpensive power transformers with a “star - double zigzag with a zero wire” (Y/2Zн) winding connection circuit with a neutral winding connection group. The paper deals with design and processes of converting electrical energy in a transformer. It has been proved that phase EMF of the secondary winding coincides in phase with the same EMF of the primary winding, i.e. the proposed circuit has a neutral windings’ connection group. Results of theoretical studies of transformer operation with an asymmetric and non-linear load are presented. Decrease in voltage asymmetry is due to the neutral sequence components compensation. Decrease of the higher harmonic voltage components level occurs due to the compensation of the higher harmonics multiplied three times. It is theoretically substantiated that transformer will not emit higher harmonic components of zero sequence voltages into the supply network. Experimental studies have confirmed the theoretical conclusions that a transformer with Y/2Zн winding connection circuit allows obtaining the highest level of voltage symmetry with an asymmetric load. In single-phase load mode, the values of voltage unbalance factor in reverse sequence do not exceed 1.7 %, in neutral sequence - 2.9 %. The transformer allows obtaining 1.2-1.5 times lower value of total harmonic components factor at non-linear load, which is the best result among circuits studied. This power transformer is resistant to load effects that distort voltage quality and is capable to provide a high level of symmetry and sinusoidal voltage as well as parallel operation with commercially available transformers. This makes it possible to use it in rural electrical networks to reduce power losses, increase service life and efficiency of electrical equipment, and increase reliability of the power supply system.

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 Elimination of interharmonic currents by a FAP using the technique of compensation global

2020 ◽  
Vol 11 (1) ◽  
pp. 228
Author(s):  
Mohamed Ali Moussa ◽  
Bachir Belmadani ◽  
Ahmed Wahid Belarbi ◽  
Rachid Taleb
Keyword(s):  
Asynchronous Motor ◽  
Distribution Network ◽  
Harmonic Distortion ◽  
Electrical Energy ◽  
Electrical Network ◽  
Pwm Inverter ◽  
Three Phase ◽  
Source Current ◽  
Quality Of Electrical Energy

<p>This document is a contribution to improve the quality of electrical energy in the distribution network.<br />In this article we will present a method that allows us to clean up in a very considerable way the electrical network of both harmonics and inter harmonics provoked, basically by the ultrafast switches used when controlling a PWM inverter supplying a three-phase asynchronous motor. We notice that this method can be generalized for other loads creating inter-harmonics.<br />This proposed method was simulated using the MATLAB/SIMULINK software and had given remarkable results (there is a considerable reduction in total harmonic distortion (THD) of source current from 29.52% to 0.82%)</p>

scholarly journals Analysis of unbalanced load low-voltage electrical networks operating modes

2021 ◽  
Vol 295 ◽  
pp. 02005
Author(s):  
Igor Naumov ◽  
Sergey Podyachikh ◽  
Dmitri Ivanov ◽  
Alexander Tretyakov ◽  
Andrey Bastron
Keyword(s):  
Low Voltage ◽  
Residential Buildings ◽  
Electrical Energy ◽  
Operating Mode ◽  
Electrical Network ◽  
Electrical Networks ◽  
Power Losses ◽  
Voltage Unbalance ◽  
Operating Modes ◽  
Unbalanced Load

The article discusses distribution electrical networks 0.38 kV operating modes, feeding individual residential buildings. The electrical energy parameters measurement were certified RESURS-UF2M device carried out. The currents and voltages time diagrams based on the measurements made and using Matlab technologies were constructed. It is established that the level of phase currents unbalance is quite high and causes significant three-phase power supply system unbalance voltage accordingly. The power of quality indicators - calculations, characterizing voltage unbalance were made, which were based on the measurements and the computer program “Asymmetry” was used. As well as the additional power losses coefficient determining by the phase currents unbalance, were calculations. Time diagrams these indicators are constructed and their analysis were made. As a result, the power of quality is significantly reduced by unbalance power consumption in the studied electrical network were founded. At the same time, the additional power losses are significant increases. Specific recommendations for the normalization electrical network-operating mode are given.

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