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.
Wang B.,Northeastern University China |
Wang B.,Shenyang University of Technology |
Zhang Q.,Northeastern University China |
Wang H.,TBEA Shenyang Transformer Group Co.
Chinese Control Conference, CCC | Year: 2013
In this paper the problem of passivity of a class of uncertain T-S fuzzy descriptor time-delay systems is analyzed. We consider the design of an integral-type sliding surface function such that the resulting sliding mode dynamics is a full-order uncertain T-S fuzzy descriptor time-delay system. A delay-dependent sufficient condition is proposed in terms of linear matrix inequality (LMI), which guarantees the sliding mode dynamics to be admissible and robustly passive. Furthermore, a SMC law is synthesized to ensure the dynamics of controlled system into a predefined switching surface in a finite time. Finally, a numerical example is provided to illustrate the effectiveness of the proposed theory. © 2013 TCCT, CAA.
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.