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Статті в журналах з теми "Коефіцієнт несиметрії"
Плахтій, Олександр Андрійович, Володимир Павлович Нерубацький, Дмитро Андрійович Шелест та Владислав Романович Цибульник. "Дослідження впливу скін-ефекту на втрати потужності в системах тягового електропостачання постійного струму". Інформаційно-керуючі системи на залізничному транспорті 26, № 4 (14 грудня 2021): 3–14. http://dx.doi.org/10.18664/ikszt.v26i4.247224.
Повний текст джерелаДисертації з теми "Коефіцієнт несиметрії"
Левицька, Олена Андріївна, та Olena Levytska. "Дослідження роботи асинхронного двигуна при несиметрії напруги мережі". Master's thesis, ТНТУ імені Івана Пулюя, 2019. http://elartu.tntu.edu.ua/handle/lib/29769.
Повний текст джерелаIn diploma work deals with the scientific research problem of practical direction for the study of electromechanical characteristics of an asynchronous motor with a short-circuited rotor with asymmetry of the network voltage. Calculations have been made to model asymmetric modes in the study of the electromechanical characteristics of an asynchronous motor with a short-circuited rotor. A scheme is developed and a simulated experimental setup for investigating the effect of voltage asymmetry and changing the frequency of voltage on the electromechanical characteristics of an asynchronous motor. Carried the analysis of systems of diagnostics and protection of the asynchronous motor during emergency modes of operation caused by the asymmetry of the network voltage.
ВСТУП ………………………………………………………………………….. 7 1 АНАЛІТИЧНА ЧАСТИНА .……………….……………………………….. 10 1.1 Аналіз заходів підвищення надійності електропостачання промислових підприємств ………………………..………………..…………………..…….… 10 1.2 Аналіз споживачів ТП 35/10 кВ ……………………………………………. 15 1.3 Висновки по першому розділі ……………………………………………… 23 2 НАУКОВО-ДОСЛІДНА ЧАСТИНА …………………………………….… 24 2.1 Вибір і обґрунтування критерію ефективності функціонування силових трансформаторів ………………………………………………………………… 24 2.2 Методи розрахунку надійності відновлювальних систем, побудованих на базі теорії масового обслуговування ………………………………..……... 27 2.3 Розрахунок надійності силових трансформаторів за даними їх експлуатації ……………………………………………………………………… 34 2.4 Висновки по другому розділі …………………………………….………… 37 3 ТЕХНОЛОГІЧНА ЧАСТИНА ………..……………….…………………… 39 3.1 Розрахунок електричних навантажень …………….………………………. 39 3.2 Розрахунок навантажень на ділянках КЛ-10 кВ ……………...…………... 42 3.3 Розрахунки з вибору перерізу проводів КЛ-10 кВ до ГРП ……………… 43 3.4 Кількість і потужність трансформаторних підстанцій ……......………….. 44 3.5 Компенсація реактивної потужності ….......……………………………… 50 3.6 Висновки по третьому розділі ……………...…………………….………… 51 4 ПРОЕКТНО-КОНСТРУКТОРСЬКА ЧАСТИНА …………...…….…….. 53 4.1 Розрахунок струмів короткого замикання ………………………………… 53 4.2 Вибір електричних апаратів та струмоведучих частин розподільчих пристроїв ……………………………………………………………………….... 60 4.3 Вибір релейного захисту …………………………………….…………….. 64 4.4 Висновки по четвертому розділі …………………………………………… 64 5. СПЕЦІАЛЬНА ЧАСТИНА ……………..………………………..………… 66 5.1 Техніко-економічне обґрунтування заміни масляних вимикачів 35, 10кВ на вакуумні …………………………………………………………………….... 66 5.2 Вибір вакуумних вимикачів 35, 10 кВ ………………………...…………… 69 5.3 Розрахунок заземлюючого пристрою районної трансформаторної підстанції 35/10 «Північна» …………...………………………..……..……….. 71 5.4 Блискавкозахист будівель і споруд на підстанції …………………………. 73 5.5 Вимоги до побудови систем автоматичного введення резерву на підприємствах …………………………………………………………………… 74 5.6 Технічна характеристика вакуумного вимикача BU/TEL-10 …………….. 78 5.7 Висновки по п’ятому розділі ………………..……………………………… 80 6 ОБГРУНТУВАННЯ ЕКОНОМІЧНОЇ ЕФЕКТИВНОСТІ …………..… 81 6.1 Планування системи планово-попереджувальних ремонтів ……..……… 81 6.2 Планування чисельності ремонтно-експлуатаційного персоналу…...…… 83 6.3 Планування кошторису експлуатаційних витрат …………………………. 86 6.4 Планування собівартості передачі і розподілу електроенергії …………... 88 6.5 Заходи щодо зменшення затрат ……………………………………………. 89 7 ОХОРОНА ПРАЦІ ТА БЕЗПЕКА В НАДЗВИЧАЙНИХ СИТУАЦІЯХ 91 7.1 Заходи з охорони праці та техніки безпеки на підстанції …………...…… 91 7.2 Заходи щодо підвищення стійкості роботи трансформаторної підстанції за умов надзвичайних ситуацій ………………………………………………… 98 8 ЕКОЛОГІЯ …………………………………………………………………… 102 Заходи по охороні навколишнього середовища на об’єкті в процесі експлуатації ………………………………………………….…………………... 102 ЗАГАЛЬНІ ВИСНОВКИ ДО ДИПЛОМНОЇ РОБОТИ …...........……….... 107 ПЕРЕЛІК ПОСИЛАНЬ ……………………………………………………….. 109
Черкашина, Галина Ігорівна. "Підвищення енергоефективності системи електропостачання за рахунок управління електричним навантаженням у побутовому секторі". Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17133.
Повний текст джерелаThe dissertation for the degree of technical sciences candidate by specialty 05.14.02 – power plants, networks and systems. – NTU "KhPI". – Kharkiv, 2015. The dissertation is devoted to theoretical substantiation and scientific problem solution concerning designing techniques of residential consumers’ electric load management. The techniques are brought to the stage of practical application to result in electric load leveling and power supply mode balancing in the residential sector. To solve this problem, a new residential power supply scheme is worked out with the ability to control the load assigned. The type and the main characteristics of household consumers-regulators are specified to allow controlling them through the day. Household consumers’ motivation for rendering of the "regulation services" is based on a proposed payment methodology taking into account participation in the load management. The overall effect of the electric load leveling based on the developed load management techniques within the United Power System of Ukraine is assessed and compared with the introduced management system cost to show the economic expediency of its implementation.
Черкашина, Галина Ігорівна. "Підвищення енергоефективності системи електропостачання за рахунок управління електричним навантаженням у побутовому секторі". Thesis, НТУ "ХПІ", 2015. http://repository.kpi.kharkov.ua/handle/KhPI-Press/17119.
Повний текст джерелаThe dissertation for the degree of technical sciences candidate by specialty 05.14.02 – power plants, networks and systems. – NTU "KhPI". – Kharkiv, 2015. The dissertation is devoted to theoretical substantiation and scientific problem solution concerning designing techniques of residential consumers’ electric load management. The techniques are brought to the stage of practical application to result in electric load leveling and power supply mode balancing in the residential sector. To solve this problem, a new residential power supply scheme is worked out with the ability to control the load assigned. The type and the main characteristics of household consumers-regulators are specified to allow controlling them through the day. Household consumers’ motivation for rendering of the "regulation services" is based on a proposed payment methodology taking into account participation in the load management. The overall effect of the electric load leveling based on the developed load management techniques within the United Power System of Ukraine is assessed and compared with the introduced management system cost to show the economic expediency of its implementation.
Гулак, Сергій Олександрович. "Підвищення енергетичних показників електровозів змінного струму за рахунок адаптованої до системи електропостачання компенсації реактивної потужності". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2020. http://repository.kpi.kharkov.ua/handle/KhPI-Press/48885.
Повний текст джерелаThesis for a Candidate Degree in Engineering (Doctor of Philosophy) in specialty 05.22.09 - "Electrotransport" 141 - Electric Power Engineering, Electrical Engineering and Electromechanics) - National Technical University "Kharkiv Polytechnic Institute", MES of Ukraine. Kharkiv, 2020. The dissertation is devoted to creation of scientific bases of choice of optimum parameters and modes of operation of the system of reactive power compensation on electric locomotives operating on alternating current. The factors that have the greatest impact on the quality of traction power supply from the side of the electric rolling stock of alternating current are analyzed. Factors that cause the greatest distortion of the voltage form of the catenary include higher harmonic components, which are introduced into the traction power supply system by electric rolling stock. It is shown that such factors as poor current collection, passage of electric rolling stock of the feeder zone, the presence of several units of electric rolling stock in one feeder zone, modes of operation of electric rolling stock lead to the fact that the process of voltage change in the catenary is nondeterministic for the analysis of the spectral composition of the traction current of an electric locomotive, the application of classical Fourier transform methods is incorrect. Analysis of circuit solutions for compensation of reactive power consumed by electric rolling stock of alternating current showed that to date the most optimal solution is the use of hybrid compensators. In such compensators, the passive part reduces the phase shift between the voltage of the secondary winding of the traction transformer and the traction current, and the active part removes the higher harmonic components of the traction current. The active part of the hybrid compensator is a stand-alone current inverter and an inverter control system. The control system performs spectral analysis of the traction current, forms an algorithm for the generation of autonomous inverter higher harmonics, the same amplitude but antiphase to the higher harmonics of the traction current. Existing control systems use Fourier transform methods to determine the spectral components of the traction current, but in real operating conditions of the electric rolling stock they are incorrect. It is proposed to apply the methods of correlation spectral analysis to determine the spectral components of the traction current. Mathematical and program-oriented models of work of traction and auxiliary drive of an electric locomotive of an alternating current (on the example of the locomotive VL-80k) have been created. The unique features of these models are the ability to take into account the mutual influence of the traction and auxiliary drives and the operating modes of electric locomotives. The technique of calculating the parameters of asynchronous motors for asymmetrical stator windings has been improved. The relationship between such parameters as the scattering inductance and the mutual inductance with the geometric parameters of the windings is shown. This technique was used to create a mathematical model for the drive of auxiliary machines, in particular for the simulation of the phase splitter. It is proposed to investigate electrodynamic processes in auxiliary machine actuators in steady state operation, to replace the phase splitter with an asymmetrical voltage system that feeds the motors of fans. The mutual influence of traction actuator and auxiliary motors operation was investigated. The results of the study made it possible to clarify the spectral composition of the current in the traction and auxiliary drive circuits. The use of a hybrid reactive power compensator in traction drive circuits is substantiated. The elements of the passive and active part of the compensator are calculated. A control system for the active part of the reactive power compensator has been developed, which is based on the block of determination of harmonic components of traction current and suppression in the current spectrum of zero and higher harmonic components. A new scientific approach to the determination of the spectral components of the traction current is proposed. It is based on the application of the linear prediction method of Levinson-Darbin. This approach allows to take into account the random nature of the voltage and, as a consequence, the traction current, and to adapt the work of the compensator to the voltage of the contact network. The application of this approach also allows taking into account such factors as the nature of the mode of operation of the electric locomotive, the passage of the boundaries of the sections of the contact network, etc. Adjusted mathematical model of traction actuator when using of reactive power compensator, calculated and constructed amplitude-frequency and phase-frequency spectral characteristics of voltage and current on the traction winding of the transformer. The power factor of the upgraded traction actuator is calculated. The justified is use of a static converter instead of a phase splitter in the auxiliary drive power supply system. The system of mathematical modeling of the auxiliary drive of the electric locomotive is executed; the amplitude-frequency and phasefrequency spectral characteristics of the voltage on the winding of the transformer and the current flowing through the winding of its own needs are calculated and constructed. The power factor of the upgraded auxiliary actuator is calculated. The losses of active and full power in the traction and auxiliary drives of the locomotive were calculated before and after the modernization. The dependences of the efficiency and the power factor of the drives before and after the modernization were calculated. The results obtained indicate that the efficiency of the traction drive after the use of the compensator decreased by 0,6% a factor and the power factor increased by 3,2%. Auxiliary drive efficiency after upgrading increased by 1,5%, and power factor increased by 26,4%. The developed scientific provisions are an effective tool for modernization of the existing fleet of electric locomotives of the VL-80t and VL-80k series and the creation of a new electric rolling stock of railways. The results of the dissertation were implemented at the Scientific Research Design and Engineering Institute of Railway Transport of OJSC "Ukrzaliznytsya" (Kyiv), SE "Ukrainian Research Institute of Carriage" (Kremenchuk) and in the educational process of the State University of Infrastructure and Technology (Kyiv).
Гулак, Сергій Олександрович. "Підвищення енергетичних показників електровозів змінного струму за рахунок адаптованої до системи електропостачання компенсації реактивної потужності". Thesis, Національний технічний університет "Харківський політехнічний інститут", 2020. http://repository.kpi.kharkov.ua/handle/KhPI-Press/48887.
Повний текст джерелаThesis for a Candidate Degree in Engineering (Doctor of Philosophy) in specialty 05.22.09 - "Electrotransport" 141 - Electric Power Engineering, Electrical Engineering and Electromechanics) - National Technical University "Kharkiv Polytechnic Institute", MES of Ukraine. Kharkiv, 2020. The dissertation is devoted to creation of scientific bases of a choice of optimum parameters and operating modes of system of compensation of reactive power on electric locomotives of alternating current. The factors that have the greatest impact on the quality of traction power supply from the side of the electric rolling stock of alternating current are analyzed. The factors that cause the greatest distortion of the voltage form of the catenary include the higher harmonic components, which are introduced into the traction power supply system by electric rolling stock. It is shown that such factors as poor current collection, passage of electric rolling stock of the feeder zone, the presence of several units of electric rolling stock in one feeder zone, modes of operation of electric rolling stock lead to the fact that the process of voltage change in the catenary is nondeterministic for the analysis of the spectral composition of the traction current of an electric locomotive, the application of classical Fourier transform methods is incorrect. The analysis of circuit solutions for the compensation of reactive power consumed by the electric rolling stock of alternating current showed that to date the most optimal solution is the use of hybrid reactive power compensators (НRPС). In such compensators, the passive part reduces the phase shift between the voltage of the secondary winding of the traction transformer and the traction current, the active part - removes the higher harmonic components of the traction current. The passive part of the НRPС is LC-filter, and the active stand-alone current inverter and control system of inverter. The control system of inverter performs spectral analysis of the traction current, forms an algorithm for the generation of autonomous inverter higher harmonics, the same amplitude but antiphase to the higher harmonics of the traction current. Existing control systems use Fourier transform methods to determine the spectral components of the traction current, but in real operating conditions of the electric rolling stock they are incorrect. It is proposed to apply the methods of correlation spectral analysis to determine the spectral components of the traction current. Mathematical and program-oriented models of operation of the traction and auxiliary drive of the AC electric locomotive (on the example of the VL-80k electric locomotive) were created. Distinctive features of these models are the ability to take into account the mutual influence of traction and auxiliary drives, as well as modes of operation of the electric locomotive. The method of calculating the parameters of induction motors with asymmetric stator windings has been improved. The relationship between parameters such as scattering inductance and mutual inductance with the geometric parameters of the windings is shown. This technique was used in the creation of a mathematical model of the drive of auxiliary machines, in particular for modeling the operation of the phase release. It is proposed to replace the phase release with an asymmetric voltage system that feeds the motor-fans to study the electrodynamic processes in the drives of auxiliary machines in steady-state operation. The mutual influence of the work of the traction drive and the drive of auxiliary machines is investigated. The results of the study allowed clarifying the spectral composition of the current in the circuits of traction and auxiliary drives. The elements of the passive and active parts of НRPС are calculated. A control system for the active part of the НRPС has been developed, the basis of which is a unit for determining the harmonic components of the traction current and removing zero and higher harmonic components from the current spectrum. A new approach to determining the spectral components of traction current is proposed. This approach is based on the application of the Levinson-Darbin linear prediction method. This approach allows to take into account the random nature of the voltage change at the current collector of the electric locomotive and, as a consequence, the traction current, and to adapt the operation of the compensator to the voltage parameters of the catenary. The application of this approach also allows taking into account such factors as the nature of the mode of operation of the electric locomotive, the passage of the boundaries of the catenary, and so on. The mathematical model of the traction drive when using НRPС is corrected, the amplitude-frequency and phase-frequency spectral characteristics of the voltage and current of the traction winding of the transformer are calculated and constructed. The power factor of the modernized traction drive is calculated. The use of a static converter instead of a phase breaker in the power supply system of auxiliary machines is substantiated. Mathematical modeling system of auxiliary drive of the electric locomotive is performed, amplitude-frequency and phase-frequency spectral characteristics of the voltage of the winding of the transformer's own winding and the current flowing in the winding of the own needs are calculated and constructed. The power factor of the modernized auxiliary drive is calculated. The losses of active and full power in the traction and auxiliary drives of the electric locomotive before and after the modernization are calculated. The dependences of factor efficiency and factor power of drives before and after modernization are calculated. The obtained results show that the factor efficiency of the traction drive after the application of the compensator decreased by 0,6%, and the power factor increased by 3,2%. The factor efficiency of the auxiliary drive after modernization increased by 1,5%, and the power factor - by 26,4%. The developed scientific provisions are an effective tool for modernization of the existing fleet of electric locomotives of the VL-80t and VL-80k series and the creation of a new electric rolling stock of railways. The results of the dissertation were implemented at the Scientific Research Design and Engineering Institute of Railway Transport of OJSC "Ukrzaliznytsya" (Kyiv), SE "Ukrainian Research Institute of Carriage" (Kremenchuk) and in the educational process of the State University of Infrastructure and Technology (Kyiv).