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Zhang S.,Shenyang University of Technology | Sun M.,Shenyang University of Technology | Tang L.,Shenyang University of Technology | Hu F.,Shenyang University of Technology | And 4 more authors.
Advanced Materials Research | Year: 2012

The thermal aging experiments on nitrile rubber (NBR) and modified NBR were carried out in 25 # transformer oil. Both of the content of CH 4, microstructure, morphology and mechanics characterization was analyzed by Gas Chromatography (GC), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS) and Servo Control material testing machine, respectively. The results shows that the amount of CH 4 released from the modified NBR is less than original NBR, and the mechanics characterization of the modified NBR is also satisfied with the application requirements. © (2012) Trans Tech Publications, Switzerland.

Geng Z.,Shenyang University of Technology | Lin X.,Shenyang University of Technology | Si B.,TBEA Shenyang Transformer Co.
2013 2nd International Conference on Electric Power Equipment - Switching Technology, ICEPE-ST 2013 | Year: 2013

Fourier transform are used on the very fast transient overvoltage (VFTO) discretion, different spectral components of transient voltage waveform are achieved. The mathematical model of the transient electric field is deduced considering dielectric polarization loss and displacement current. FEM is adopted to calculate the transient electric field of gas insulated switchgear disk insulator under the condition of VFTO, potential distribution curves at key point time are shown, which are compared with the one in the quiescent state. The tangential electric field strength and normal electric field strength along with radial direction on the insulator surface are illustrated. Some effects of typical positions electric field strength along with time are shown in this paper. The references for GIS insulation design are provided. © 2013 IEEE.

Guangfan L.,China Electric Power Research Institute | Bo L.,China Electric Power Research Institute | Jingzhong L.,China Electric Power Research Institute | Zhigang Z.,China Electric Power Research Institute | And 4 more authors.
European Transactions on Electrical Power | Year: 2012

SUMMARY The Jingdongnan-Nanyang-Jingmen UHV AC Pilot Project has already been put into service in China. In this paper, insulation level of power transformer and shunt reactor for 1000-kV power transmission project in China are introduced. UHV AC transformer and shunt reactor structures are given. Key technologies, including cooling type, regulating method for UHV AC transformer, pattern of outgoing line, and noise controlling, are discussed. Besides, due to the high voltage class, high capacity, and super size of UHV power transformer, the size of its test circuit is correspondingly enlarged, the impacts of stray inductance and capacitance will be more intense consequentially, thus in factory test including lighting impulse test, switching impulse voltage test, short-duration induced AC voltage test at 500-kV side, and long-duration induced AC voltage test with partial discharge measurement are presented. Copyright © 2011 John Wiley & Sons, Ltd.

Xie Q.,Tongji University | Ma G.,Tongji University | Zhu R.,CAS Institute of Electrical Engineering | Qiu N.,State Grid Corporation of China | Xin Z.,TBEA Shenyang Transformer Co.
Zhongguo Dianji Gongcheng Xuebao/Proceedings of the Chinese Society of Electrical Engineering | Year: 2015

Transformers are essential substation equipment, while they suffered from various damages in earthquakes. Two 220 kV porcelain bushings and transformer tank which constituted a transformer-bushing system were utilized as the test object, shaking table tests were carried out on the system. Seismic responses at key positions of the system under excitations of earthquake ground motions, which satisfy IEEE 693 required response spectra excitation, were measured. Take the system earthquake responses under El Centro earthquake record excitation for example, acceleration and displacement responses along the height of the system were analyzed, finally earthquake response mechanisms of the transformer turret and bushing were analyzed. Fundamental dynamic characteristics of the system were acquired, and cushion slippage and oil leakage at bushing flange were observed under earthquake record with peak ground acceleration (PGA) of 0.3 g excitation. Analyses indicate: when the bending stiffness of the bushing flange is large enough, the out-of-plane flexibility of transformer tank walls magnifies dynamic responses of the bushings and contributes to turret rocking vibration. There is a significant coupling interaction between bushing vibration and turret rocking vibration, and turret and bushings as a whole rock around turret bottom flange. However, when the bending stiffness of the bushing flange turned smaller, bushings rock around its flange alone, the coupling interaction between bushing vibration and turret rocking vibration became weak. © 2015 Chinese Society for Electrical Engineering.

Hu F.,Shenyang University of Technology | Hu F.,AVIC Shenyang Aircraft Corporation Ltd. | Tang L.,Shenyang University of Technology | Zhang S.,Shenyang University of Technology | And 3 more authors.
Advanced Materials Research | Year: 2013

The formation of CH4 from two kinds of NBR with different raw rubber applied in transformer oil were investigated. In this study, work environment of transformer was simulated, thermal aging tests were conducted for different times in 70°C transformer oil. Surface morphology, the release of CH4, and molecular structure were analyzed by using Gas Chromatography (GC), Scanning Electron Microscope (SEM),and Fourier Transform Infrared analysis (FTIR), respectively. In addition, the swelling property was also discussed in this work. The results illustrated that raw rubber with more content of acrylonitrile had excellent advantages in heat oil aging resistance and the formation of CH4. © (2013) Trans Tech Publications, Switzerland.

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