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Yu L.,Shenyang Institute of Engineering | Yuan S.,Northeast China Bureau of State Electricity Regulatory Commission of China | Li F.,Northeast Electric Power Research Institute
Proceedings - International Symposium on Discharges and Electrical Insulation in Vacuum, ISDEIV | Year: 2012

A new type of 'dual-contact' structure of vacuum interrupter is proposed in the paper. It consists of main contact and arc contact, which are used to carry rated current and break short circuit current, respectively. During the closing/opening of vacuum circuit breaker, arc contact is first closed and post breaking, however, main contact is post closed and first breaking. So there must be the current transfer process. In this paper, during the breaking process of vacuum circuit breaker, a model of current transfer is used in the investigation of current transfer, and the maximum possible current transfer time is obtained. This analysis is helpful to the research of large current vacuum interrupters with dual-contact. © 2012 IEEE.

Li X.W.,Northeastern University China | Peng N.,Northeastern University China | Wu X.M.,Northeast Electric Power Research Institute | Wang Z.G.,CAS Shenyang Institute of Metal Research
Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science | Year: 2014

Dislocation structures in [1̄12] Cu-7 at. pct Al alloy single crystals cyclically deformed at different plastic strain amplitudes were investigated by transmission electron microscope (TEM) and compared with the results of [1̄12] Cu single crystals. It is found that the plastic strain amplitude γpl has an obvious effect on the slip deformation mode, and consequently on the cyclic hardening behavior of [1̄12] Cu-7 at. pct Al alloy single crystals with an intermediate stacking fault energy. For instance, a high slip planarity (i.e., only formation of planar-slip bands) contributes to the occurrence of a gentle cyclic hardening with a much lower saturation stress at a low γpl of 4.5 × 10-4. A mixed planar/wavy-slip mode (e.g., persistent Lüder's bands/wall-like micro structures) at an intermediate γpl of 2.2 × 10 -3 causes an obvious cyclic hardening up to a comparable saturation stress to that for the [1̄12] Cu single crystal. In contrast, the deformation mode is dominated by wavy slip (e.g., ill-defined dislocation cells and walls) at the highest γp1 of 7.2 × 10-3, causing that its cyclic hardening curve is quite similar to that for the [1̄12] Cu single crystal; in this case, a slightly higher saturation stress level than that for the Cu single crystal is reached due to the additional solid solution strengthening. © The Minerals, Metals & Materials Society and ASM International 2014.

Yuan J.,CAS Shenyang Institute of Metal Research | Wu X.,Northeast Electric Power Research Institute | Wang W.,CAS Shenyang Institute of Metal Research | Zhu S.,CAS Shenyang Institute of Metal Research | Wang F.,CAS Shenyang Institute of Metal Research
Oxidation of Metals | Year: 2013

The effect of surface finish on the scaling behavior of Super 304H was investigated in steam and supercritical water (SCW). The oxide scales were analyzed using scanning electron microscope with an energy dispersive X-ray detector, X-ray diffraction, and Raman spectroscopy. The results showed that surface deformation improved the oxidation resistance by promoting the preferable formation of chromia and improving the scale adhesion. In SCW, the absence of hematite may be ascribed to the low oxygen partial pressure; while the whisker growth on the sandblasted sample may have resulted from the low oxygen partial pressure and the increased chromium diffusion flux. © 2013 Springer Science+Business Media New York.

Lu Q.,Dalian University of Technology | Wang W.,Jilin Electric Power Research Institute | Han S.,Northeast China Bureau of Electricity Regulatory Commission of China | Yuan S.,Northeast China Bureau of Electricity Regulatory Commission of China | And 2 more authors.
Dianwang Jishu/Power System Technology | Year: 2013

With the increase of wind power curtailment more and more, how to effectively evaluate the wind power curtailment in future power grid becomes an important problem, which both macroscopic decision-making departments and wind power generation enterprises pay special attention to. A new evaluation method for wind power curtailment is proposed, and its principle is as following: for a certain level year, firstly based on typical daily load curve of each month the load curves of all days in the month are simulated, and then by means of analyzing peak load regulation ability of power sources the power grid's space of accommodating wind power is attained; secondly the historical p.u. curve of wind power multiplied by the planned installed capacity of wind power generators is taken as the possible wind power output curve; thirdly through the comparison of power grid's space to accommodate wind power with the possible wind power output curve the time-sequence curve of curtailed wind power of each day can be obtained. Using this curve various kind of data, such as annual wind power curtailment ratio, annual utilization hours, duration curve of annual curtailed wind power, monthly distribution of annual wind power curtailment and peak-valley distribution of annual wind power curtailment can be achieved by statistics thus the situation of wind power curtailment in the level year can be fully reflected. Using the proposed method, the situation of wind power curtailment within Northeast power grid in 2015 is evaluated.

Zhao H.,Shenyang University of Technology | Bai C.,Shenyang University of Technology | Zhu S.,Northeast Electric Power Research Institute
Applied Mechanics and Materials | Year: 2011

Search engines can bring a lot of benefit to the website. For a site, each page's search engine ranking is very important. To make web page ranking in search engine ahead, Search engine optimization (SEO) make effect on the ranking. Web page needs to set the keywords as "keywords" to use SEO. The paper focuses on the content of a given word, and extracts the keywords of each page by calculating the word frequency. The algorithm is implemented by C # language. Keywords setting of webpage are of great importance on the information and products © (2011) Trans Tech Publications.

Fang G.,Northeast Electric Power Research Institute
Proceedings - 2013 5th Conference on Measuring Technology and Mechatronics Automation, ICMTMA 2013 | Year: 2013

It is the guarantee of the economic benefits to the coal fired power plant that turbine generator is safe and stable operation, before the turbine is putting into production operation, it must ensure that the MSV, RSV, GV and CV of turbine have a good valves leak, this is the premise safeguard to the safe and stable operation of the unit, in this paper, it is mainly to analysis that how to ensure the turbine valves leak. © 2013 IEEE.

Fang G.C.,Northeast Electric Power Research Institute
Advanced Materials Research | Year: 2012

The phenomenon of higher shaft vibration and higher bearing temperature is repeated happening during the starting of the 1 000MW coal fired unit of Suizhong power station, seriously endanger the safe operation of the unit, this article mainly aims at the difficult problem of this one technology, by researching on steam turbine work principle and vibration analysis, to find the reason of effect on stability, and to correct all unreasonable factors, to ensure the safe and stable operation of the unit, to laid solid foundation for the construction of the intelligent power grid. © (2012) Trans Tech Publications, Switzerland.

Feng S.,North China Electrical Power University | Zhu L.,North China Electrical Power University | Liu Z.,Northeast Electric Power Research Institute
Proceedings - 2012 International Conference on Computer Science and Electronics Engineering, ICCSEE 2012 | Year: 2012

Smart meter is an intelligent instrumentation whose core is the microprocessor application and network communication technology. Smart meter is getting the popularizing and applying at home and abroad. Except for having the basic function of the two-way measurement, Smart meter also has other various functions, for example, the point classification measurement, two-way communication, various control models, a variety of data transmission mode, preventing electricity-stolen. This paper introduces the working principle of the smart meter, expounds the application of zero line current transformer for smart meter, analyzes the actual connection mode of smart meter installation, proposes the problems should be paid attention to when the smart meter is installed, and the last gives the relevant solutions. © 2012 IEEE.

Hao J.-C.,Northeast Electric Power Research Institute | Zhang J.-Y.,Northeast Electric Power Research Institute | Tian Y.,Northeast Electric Power Research Institute
Gaoya Dianqi/High Voltage Apparatus | Year: 2010

An accident of breakdown across the interrupter of circuit-breaker caused by multi-lightning strike on lines was introduced. Based on the principle of lightning surge wave, the breakdown reason was analyzed and a simulation model was established according to reality of field engineering, the model was simulated and analyzed by EMTP (electromagnetic transients program). Theoretical analysis and simulation results confirm the interrupter's breakdown. In response to this situation, a method is hence proposed to prevent the fault by setting a mental ZnO surge arrester, or setting a mental ZnO surge arrester with gap at line terminal tower if there is no position for setting the arrester within substation.

Xu J.,Shenyang University of Technology | Wang L.,Shenyang University of Technology | Li S.,Northeast Electric Power Research Institute
Gaodianya Jishu/High Voltage Engineering | Year: 2012

The ultra-high voltage (UHV) system has the properties of high voltage grade, huge transmission capacity and rather severe electromagnetic transient problems. In order to study the transient characteristics of enclosure voltage while the disconnector operating in ultra high voltage gas insulated substation (GIS) and to provide references for the construction and insulation coordination of UHV GIS, we analyzed the calculation theory of transient enclosure voltage (TEV) of UHV GIS by taking a 1100 kV GIS in China as an example, calculated transient enclosure voltages at each point of GIS by using multi-conductor transmission line model, and analyzed the voltage frequency spectrum. Moreover, we analyzed factors affecting transient enclosure voltage such as operation modes, operation phases, grounding pattern of the disconnector, and so on. Simulation results show that the maximum value of TEV occurs at different positions due to different operation modes and the amplitude of TEV has symmetry due to layout symmetry of GIS outlet section.

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