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Zhang Jianp - One of the best experts on this subject based on the ideXlab platform.
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simulation research on earth fault characteristics of modular multilevel converter based high voltage Direct Current transmission system
Power system technology, 2014Co-Authors: Zhang JianpAbstract:The sub-module cascading structure is applied in the modular multilevel converter based high voltage Direct Current(MMC-HVDC) transmission system to solve the dynamic voltage balancing brought by Directly series-connected switching elements, and the MMC-HVDC transmission system possesses such advantages as high quality of output voltage waveform, lower switching frequency and lower loss and so on, so it becomes one of the power transmission technology that exists high market value. Because the working principle, the modulation strategy and the topological structures of MMC-HVDC transmission system are different from those of traditional HVDC transmission system and voltage source converter based high voltage Direct Current(VSC-HVDC) transmission system, different fault characteristics appear in MMC-HVDC transmission system under unbalanced grid conditions. Taking the earth fault occurred at the AC system side, the valve side and the DC system side as the cases respectively and considering the influence of connection modes of transformer windings on fault characteristics, based on the simulation model of MMC-HVDC transmission system constructed in PSCAD/EMTDC different fault characteristics under different transformer winding connection modes as well as the influence of above-mentioned three kinds of faults on the operation of MMC-HVDC transmission system are analyzed, and the strategies to cope with these faults are put forward.
Gilsoo Jang - One of the best experts on this subject based on the ideXlab platform.
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a study on maximum wind power penetration limit in island power system considering high voltage Direct Current interconnections
Energies, 2015Co-Authors: Minhan Yoon, Yong Tae Yoon, Gilsoo JangAbstract:The variability and uncontrollability of wind power increases the difficulty for a power system operator to implement a wind power system with a high penetration rate. These are more serious factors to consider in small and isolated power systems since the system has small operating reserves and inertia to secure frequency and voltage. Typically, this difficulty can be reduced by interconnection with another robust power system using a controllable transmission system such as a High-Voltage Direct Current (HVDC) system. However, the reliability and stability constraints of a power system has to be performed according to the HVDC system implementation. In this paper, the method for calculation of maximum wind power penetration in an island supplied by a HVDC power system is presented, and the operational strategy of a HVDC system is proposed to secure the power system reliability and stability. The case study is performed for the Jeju Island power system in the Korean smart grid demonstration area.
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modeling and control of igbt converter based high voltage Direct Current system
Journal of The Korean Institute of Illuminating and Electrical Installation Engineers, 2011Co-Authors: Hongwoo Kim, Gilsoo JangAbstract:This paper presents modeling and control for the emerging IGBT converter-based High-Voltage Direct-Current system (IGBT-HVDC). This paper adds to the representation of the IGBT-HVDC system in the dq-synchronous reference frame and its decoupled control scheme. Additionally, since the IGBT-HVDC is able to actively support the grid due to its capacity to control independently active and reactive power production, a reactive power control scheme is presented in order to regulate/contribute to the voltage at a remote location by taking into account its operational state and limits. The ability of the control scheme is assessed and discussed by means of simulations using ahybrid power system, which consists of a permanent magnetic synchronous-generator (PMSG) based wind turbine, an IGBT-HVDC, and a local load.
Khominich V. - One of the best experts on this subject based on the ideXlab platform.
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CHARACTERISTICS OF SPECIALIZED SINGLE-PHASE HIGH VOLTAGE DOUBLER RECTIFIER
'National Technical University Kharkiv Polytechnic Institute', 2018Co-Authors: Brzhezitsky V. O., Vendychanskyi R., Trotsenko, Ye. O., Haran, Ya. O., Desyatov O. M., Khominich V.Abstract:Introduction. To obtain a high voltage Direct Current, voltage multipliers with a number of cascades of three or more are widely used. At the same time, for voltage levels of 100…200 kV there are several advantages of using a specialized single-phase high voltage doubler rectifier. Problem. The main difficulty is that at the moment mathematical modeling has not been worked out for describing modes that use the built-in R, C-filter, as well as a nonlinear load in the form of Zener diodes. Goal. Generalization of the results of the authors' previous publications on the development of an analytical method for calculating the modes of a typical High-Voltage Direct Current installation based on a specialized single-phase voltage doubler rectifier. Methodology. Compilation of a system of algebraic linear and nonlinear equations that describe the Current and voltage modes in the elements of a typical High-Voltage Direct Current installation with a nonlinear load. Results. It is shown that with the use of linearization of the Current-voltage characteristics of Zener diodes used in the load circuits of a typical High-Voltage Direct Current installation, an analytical solution for the voltages and Currents in its elements can be obtained. Originality. The theoretical basis of the complex solution of the system of equations for the Currents, voltages and power of the elements of a typical High-Voltage Direct Current installation with the account of nonlinear pulsations is formulated for the first time. Practical value. The obtained theoretical results can be used for calculations, design, optimization of the modes for a wide range of High-Voltage Direct Current installations of technical, technological, and measuring purposes in the range up to 100...200 kV.Цель. Обобщение результатов предыдущих публикаций авторского коллектива по разработке аналитического метода расчёта режимов типовой установки высокого напряжения постоянного тока на основе специализированного однофазного выпрямителя с удвоением напряжения. Методика. Составление системы алгебраических линейных и нелинейных уравнений, описывающих режимы тока и напряжения в элементах типовой схемы установки высокого напряжения постоянного тока с нелинейной нагрузкой. Результаты. Показано, что с применением линеаризации вольт-амперных характеристик стабилитронов, используемых в цепях нагрузки типовой установки высокого напряжения постоянного тока, может быть получено аналитическое решение для напряжений и токов в её элементах. Научная новизна. Впервые сформулирован теоретический базис комплексного решения системы уравнений для токов, напряжений и мощности элементов типовой установки высокого напряжения постоянного тока с учётом нелинейных пульсаций. Практическая значимость. Полученные теоретические результаты могут быть использованы для расчётов, проектирования, оптимизации режимов широкого спектра установок высокого напряжения постоянного тока технического, технологического, а также измерительного предназначения в диапазоне до 100…200 кВ
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Characteristics of specialized single-phase high voltage doubler rectifier
'National Technical University Kharkiv Polytechnic Institute', 2018Co-Authors: Brzhezitsky V. O., Vendychanskyi R., Trotsenko, Ye. O., Haran, Ya. O., Desyatov O. M., Khominich V.Abstract:To obtain a high voltage Direct Current, voltage multipliers with a number of cascades of three or more are widely used. At the same time, for voltage levels of 100…200 kV there are several advantages of using a specialized single-phase high voltage doubler rectifier. The main difficulty is that at the moment mathematical modeling has not been worked out for describing modes that use the built-in R, C-filter, as well as a nonlinear load in the form of Zener diodes. Generalization of the results of the authors' previous publications on the development of an analytical method for calculating the modes of a typical High-Voltage Direct Current installation based on a specialized single-phase voltage doubler rectifier. Compilation of a system of algebraic linear and nonlinear equations that describe the Current and voltage modes in the elements of a typical High-Voltage Direct Current installation with a nonlinear load. It is shown that with the use of linearization of the Current-voltage characteristics of Zener diodes used in the load circuits of a typical High-Voltage Direct Current installation, an analytical solution for the voltages and Currents in its elements can be obtained. The theoretical basis of the complex solution of the system of equations for the Currents, voltages and power of the elements of a typical High-Voltage Direct Current installation with the account of nonlinear pulsations is formulated for the first time. The obtained theoretical results can be used for calculations, design, optimization of the modes for a wide range of High-Voltage Direct Current installations of technical, technological, and measuring purposes in the range up to 100...200 kV.Обобщение результатов предыдущих публикаций авторского коллектива по разработке аналитического метода расчёта режимов типовой установки высокого напряжения постоянного тока на основе специализированного однофазного выпрямителя с удвоением напряжения. Составление системы алгебраических линейных и нелинейных уравнений, описывающих режимы тока и напряжения в элементах типовой схемы установки высокого напряжения постоянного тока с нелинейной нагрузкой. Показано, что с применением линеаризации вольт-амперных характеристик стабилитронов, используемых в цепях нагрузки типовой установки высокого напряжения постоянного тока, может быть получено аналитическое решение для напряжений и токов в её элементах. Впервые сформулирован теоретический базис комплексного решения системы уравнений для токов, напряжений и мощности элементов типовой установки высокого напряжения постоянного тока с учётом нелинейных пульсаций. Полученные теоретические результаты могут быть использованы для расчётов, проектирования, оптимизации режимов широкого спектра установок высокого напряжения постоянного тока технического, технологического, а также измерительного предназначения в диапазоне до 100…200 кВ
Yong Cui - One of the best experts on this subject based on the ideXlab platform.
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WSN-Based Measurement of Ion-Current Density Under High-Voltage Direct Current Transmission Lines
IEEE Access, 2019Co-Authors: Yong Cui, Xiao Song, Luxing Zhao, Haiwen Yuan, Chen WangAbstract:Ion-Current density is a significant indicator of electromagnetic environment under high voltage Direct Current lines. To improve measurement accuracy and convenience, this paper concluded factors that affect measurement results and a wireless measurement method was proposed. Wilson plate kind of sensor was designed according to the IEEE standard. The ion Current was measured and digitalized by the measurement device, and the signal was transmitted to the computer via wireless sensor networks. The data were analyzed and recorded by automatic measurement software. Finally, the measurement system was calibrated and some field tests had been performed, the results show that the measurement system possesses the merits of good accuracy, simple structure, convenient operation, and high stability and reliability. The maximum Current measurement error is less than 3%.
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model design and testing of field mill sensors for measuring electric fields under high voltage Direct Current power lines
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Yong Cui, Xiao Song, Luxing Zhao, Haiwen Yuan, Yumeng Liu, Liwei LinAbstract:High-Voltage Direct-Current (HVdc) transmission lines have been implemented in many countries, including Australia, Brazil, China, and Sweden, and the safety concerns as the result of the high electromagnetic-radiation underneath the HVdc lines have garnered increased public attentions. Here, we report on the model, design, and testing of field-mill electric field sensors to measure the electric field at the ground level under the HVdc transmission lines. This study utilized a finite-element analysis method to establish numerical simulation results based on the electrical and mechanical parameters to achieve optimal designs with experimental calibrations. Afterward, these sensors were successfully tested and utilized at the national High-Voltage test base.
Haiwen Yuan - One of the best experts on this subject based on the ideXlab platform.
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WSN-Based Measurement of Ion-Current Density Under High-Voltage Direct Current Transmission Lines
IEEE Access, 2019Co-Authors: Yong Cui, Xiao Song, Luxing Zhao, Haiwen Yuan, Chen WangAbstract:Ion-Current density is a significant indicator of electromagnetic environment under high voltage Direct Current lines. To improve measurement accuracy and convenience, this paper concluded factors that affect measurement results and a wireless measurement method was proposed. Wilson plate kind of sensor was designed according to the IEEE standard. The ion Current was measured and digitalized by the measurement device, and the signal was transmitted to the computer via wireless sensor networks. The data were analyzed and recorded by automatic measurement software. Finally, the measurement system was calibrated and some field tests had been performed, the results show that the measurement system possesses the merits of good accuracy, simple structure, convenient operation, and high stability and reliability. The maximum Current measurement error is less than 3%.
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model design and testing of field mill sensors for measuring electric fields under high voltage Direct Current power lines
IEEE Transactions on Industrial Electronics, 2018Co-Authors: Yong Cui, Xiao Song, Luxing Zhao, Haiwen Yuan, Yumeng Liu, Liwei LinAbstract:High-Voltage Direct-Current (HVdc) transmission lines have been implemented in many countries, including Australia, Brazil, China, and Sweden, and the safety concerns as the result of the high electromagnetic-radiation underneath the HVdc lines have garnered increased public attentions. Here, we report on the model, design, and testing of field-mill electric field sensors to measure the electric field at the ground level under the HVdc transmission lines. This study utilized a finite-element analysis method to establish numerical simulation results based on the electrical and mechanical parameters to achieve optimal designs with experimental calibrations. Afterward, these sensors were successfully tested and utilized at the national High-Voltage test base.
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Design and modeling of space charge density sensor based on ion counting under high voltage Direct Current transmission lines
2018 13th IEEE Conference on Industrial Electronics and Applications (ICIEA), 2018Co-Authors: Chao Zeng, Haiwen Yuan, Yuekui Zhang, Yingyi LiuAbstract:The space charge around the high voltage Direct Current (HVDC) transmission line has an important influence on its electromagnetic environment. To study the distribution of charge density under HVDC transmission line and its influence mechanism on the electromagnetic environment of transmission line, it is an effective method to measure the space charge density around the transmission line. In this paper, we design and model the space charge density sensor to measure the space charge density under HVDC transmission line. The sensor is structurally optimized by qualitatively and quantitatively analyzing the mechanical structure of the space charge density sensor. The space charge density sensor has been successfully tested and applied in the HVDC test base.
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development and application of high frequency sensor for corona Current measurement under ultra high voltage Direct Current environment
IEEE Transactions on Instrumentation and Measurement, 2012Co-Authors: Haiwen Yuan, Qinghua Yang, Yuanqing Liu, S A AkhtarAbstract:Corona Current measurement is essential for research into corona discharge under ultra High-Voltage Direct-Current (HVDC) environment. The sensor is extremely important due to the small (microampere) amplitude of the corona Current and the wide (dc to tens of megahertz) range in frequency. In this paper, a high-frequency sensor is described, and its application is introduced for accurate measurement of corona Current under HVDC environment. Based on the finite-element method and the charge simulation method, the structure of the sensor is determined considering a ±1200-kV environment. The sensor is immune to the effects from the external environments such as vibration and temperature changes. Results indicate that the sensor is feasible for corona Current measurement.