Sun C.,Dalian University of Technology |
Nian K.,Dalian University of Technology |
Wu Y.,Dalian University of Technology |
Xue J.,TBEA Shenyang Transformer Group Co. |
Peng N.,TBEA Shenyang Transformer Group Co.
Gaodianya Jishu/High Voltage Engineering | Year: 2016
The oil-paper insulation system of converter transformer in operation needs to withstand the composite voltage, its insulation aging characteristics are greatly different from those of general power transformer, but research is very insufficient. In order to obtain insulation aging law of oil-paper insulation under different composite voltages, we used laboratory accelerated composite electrical aging method to age oil-paper insulation, measured the polarization and depolarization current of oil-paper structure and insulating papers' degree of polymerization in different stages, and researched insulating properties of oil-paper structure that combined time dielectric response method and degree of polymerization. The results show that,with the increase of aging time, the whole PDC curves move upward, the stable polarization current values increase, the depolarizing current tends to zero, at the same time, the degree of polymerization of oil-paper is declining. With the increase of the percentage of the AC voltage, the influence of the degree of polymerization of oil-paper from near high voltage side to the middle layer is intensifying. Finally, we propose a nondestructive testing method that combines time dielectric response and degree of polymerization, this study will provide references for aging mechanism of oil-paper under AC-DC combined voltages and insulation design of converter transformer. © 2016, High Voltage Engineering Editorial Department of CEPRI. All right reserved.
Jing Y.T.,Shenyang University of Technology |
Li Y.,Shenyang University of Technology |
Li L.,Shenyang University of Technology |
Jiang M.H.,TBEA Shenyang Transformer Group Co. |
Wang N.,TBEA Shenyang Transformer Group Co.
Applied Mechanics and Materials | Year: 2014
Hot-spot calculation of structure parts in large power transformer has been concerned by transformer designer and researcher. The key is the calculation of leakage magnetic field, loss and temperature rise in structure parts of transformer, belongs to the calculation of the electromagnetic-thermal coupling field. This paper calculate and analysis electromagnetic field and temperature field of a transformer tank using ANSYS analysis software based on electromagnetic fields, heat transfer theory, and the results and the test data are in good agreement; aim at the problem of local overheating, appropriate magnetic shields are used to reduce the stray losses and hot-spot temperature-rise in transformer structure parts. so the calculation method can be applied engineering design. © (2014) Trans Tech Publications, Switzerland.
Kang Y.,Shenyang University of Technology |
Kang Y.,TBEA Shenyang Transformer Group Co. |
Bai B.,Shenyang University of Technology |
Guo Y.,TBEA Shenyang Transformer Group Co.
Diangong Jishu Xuebao/Transactions of China Electrotechnical Society | Year: 2014
A 3D transient finite element analysis method coupled electric circuit equations for 3D magnetic leakage field and losses of the structural parts for large power transformer is investigated considering electromagnetic characteristics of ferromagnetic material such as nonlinear and anisotropic in this paper. Measured and computed results of losses to the model indicate the validity of the method proposed using the TEAM Workshop Problem 21C-M1 model as the numerical example. And this method is also applied to numerical calculation for a single-phase auto-power transformer, the calculation error of the structural parts losses is 3.64%, which indicates the validity and feasibility of the method and makes the accurate loss calculation of the structures of large power transformer possible.
Yan X.,Shenyang University of Technology |
Huang F.,Shenyang University of Technology |
Kang Y.,TBEA Shenyang Transformer Group Company Ltd |
Zhang Y.,Shenyang University of Technology
Advanced Materials Research | Year: 2013
With the rapid development of economy and construction of large-scale hydropower, thermal power and nuclear power base, the demand of long-distance, high-capacity transmission of UHV (ultra high voltage) is increasing in China. This paper presents the application of finite element method (FEM), software ANSYS in the magnetic field of core about single-phase three-winding 750KV autotransformer with the next column excitation regulator device. As most driving sources applied to transformers are voltage sources, field-circuit coupling method is generally used in solving electromagnetic field of transformers, so this paper is written to verify if the simulation results are similar to the qualification and to prove the correctness of the method and the practical value. © (2013) Trans Tech Publications, Switzerland.
Zhang Y.,Shenyang University of Technology |
Liu Y.,Baoding Tianwei Group Co. |
Xie D.,Shenyang University of Technology |
Bai B.,Shenyang University of Technology |
And 2 more authors.
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2013
In order to improve the computation efficiency of rotating losses of electric steel sheet, a method calculating transformer iron core losses which can make the process of finite element analysis simplified was proposed in this paper. In this method, the measurement results of rotating loss of single electric steel sheet were the input data. During the course of the finite element computation, two orthogonal B-H curves were used to take the magnetic anisotropic property of grain-oriented silicon steel into account, and the Newton-Raphson method was employed to solve the nonlinear finite element equation. Then, the core loss distribution was obtained by checking the corresponding rotating loss measurement curves according to the magnetic flux density value in each discretization element. By comparing the simulation results with experimental test ones for a transformer core model, the effectiveness of the proposed method is testified. © 2013 Chinese Society for Electrical Engineering.
Song Y.,Northeast Electric Power Research Institute |
Liu J.,Northeast Electric Power Research Institute |
Yuan S.,Northeast China Bureau of SERC |
Zhao C.,TBEA Shenyang Transformer Group Co.
2011 International Conference on Electrical and Control Engineering, ICECE 2011 - Proceedings | Year: 2011
With the growing of cable outlets in distribution network, the ground current increases quickly when single-phase ground fault occurs. Which results show single-phase ground fault protection mode selection becomes difficult. Based on interval analytic hierarchy process (IAHP), the comprehensive evaluation method for single-phase ground fault protection modes in cable network was researched. Indicators for comprehensive evaluation were obtained, the steps of evaluation method were gained, and evaluation process was given. An example proves that the evaluation method is simple and effective and the workload is not too big, so this method is worthy applying for evaluation of fault protection modes in other kinds' distribution network. Evaluation results provide theoretical basis and reference for operation units and design departments. © 2011 IEEE.
Chen D.M.,TBEA Shenyang Transformer Group Co. |
Liu K.,Shenyang Machine Tool Group CO. |
Li X.,Shenyang Machine Tool Group CO. |
Tan Z.,Shenyang Machine Tool Group CO.
Advanced Materials Research | Year: 2014
Domestic CNC machine tool and NC machine tools abroad's main gap is accuracy stabilization rather than accuracy. Accuracy stabilization test is done on some three-axis vertical machining center aiming at the status. Laser interferometer is used to test X, Y, Z axis's positioning accuracy, repeat positioning accuracy and reverse gap. The test is done taking 80 days as the period. The accuracy test results is analyzed. From the positioning accuracy, repeat positioning accuracy and reverse gap curves we can see that, because of the factors of machine's use and temperature's change, X, Y, Z axis's positioning accuracy changes violently, repeat positioning accuracy and reverse gap change a little. © (2014) Trans Tech Publications, Switzerland.
Xiao G.,TBEA Shenyang Transformer Group Co.
Gaoya Dianqi/High Voltage Apparatus | Year: 2015
Two barrier systems of converter transformer were designed with same thickness of insulation pressboard cylinder and different oil gap. To compare their insulating strength, the software ElecNet is adopted to calculate the electric field intensities and withstand voltages of two designed barrier systems. The results show that the electric field intensity of the barrier system with smaller oil gap is lower than that of the other barrier system, suggesting that the barrier system with smaller oil gap is more applicable. ©, 2015, Xi'an High Voltage Apparatus Research Institute. All right reserved.
TBEA Shenyang Transformer Group Co. | Date: 2011-03-30
This invention relates to a self power-acquiring quickly responsive controllable reactor whose coil of the main body portion contains a control winding(6), a net-side winding(5), further contains a tertiary winding (7). the tertiary winding(7), the control winding(6) and the net-side winding (5) are set in turn on a magnetic conductive core column of the main body portion (1) from inside to outside; the net-side winding(5) has power-acquiring taps; which connect with the primary coil of rectiformer in a rectifying-filtering unit (2). The output terminals of the rectifying-filtering unit (2) connect with the control winding (6). A quick switch (K) is in parallel connected with the tertiary winding (7). The on/off state of the quick switch (K) is controlled by the command transmitted by the control unit (4) in the controllable reactor. This invention uses an additional tertiary winding to control the power system through the high speed switch and the control unit in the case of short circuit to meet the quick response when the controllable reactor is in fault. Moreover, this controllable reactor has an excellent obtaining effect and wide applications.
Xing J.Q.,TBEAShenyang Transformer Group CO. |
Chen L.,ShenyangUniversity of Technology |
Xing Z.X.,ShenyangUniversity of Technology
Advanced Materials Research | Year: 2014
In order to restrict over-voltage and compensate line charging power, there is a need to install high compensation shunt reactors in ultra-high voltage AC transmission lines. Due to the saturation characteristic of core limb during the working progress in the magnetically controlled shunt reactor (MCSR), the current higher harmonics exist in the high voltage winding. Based on finite element, the method which analyzes the controlling characteristic of high voltage winding with 500kVMCSR demonstration project in the Jiangling converter station is presented in this paper. The magnitude and frequency of harmonic current in the high voltage winding current is derived by this method. Through the comparisonwith the measured results of 500kVMCSR, the validity of method is proved. © (2014) Trans Tech Publications, Switzerland.