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DC ice-melting model for wet-growth icing conductor and its experimental investigation

Science china(Technological Sciences) 2010年第12期53卷 3248-3257页

作者： FAN SongHai1,2, JIANG XingLiang1, SHU LiChun1, SUN CaiXin1 & WANG DaXing1,2 1 State Key Laboratory of power Transmission Equipment & System Security and New Technology, Chongqing University, Chongqing 400044, china 2.sichuan electric power test and research institute, chengdu 610072. china 1. State Key Laboratory of power Transmission Equipment & System Security and New Technology Chongqing University Chongqing 400044 China2. Sichuan Electric Power Test and Research Institute Chengdu 610072 China

Icicles are often formed under the downside surface of conductor in the wet growth icing of overhead power line. When the ice deposit around overhead power line is molten by Joule heat produced by current, the pattern of heat transfer of ice deposit with icicles is dissimilar to that without icicle, so the ice-melting model for the columnar icing conductor cannot be applied to icicle-shaped icing conductor. According to the heat-transfer characteristic of the icicle-shaped icing conductor, this paper puts forward a DC ice-melting model for the icicle-shaped icing conductor. Because this full model includes three-dimensional heat-transfer and interface movement, which cannot be solved in closed form, a finite element scheme in space-domain and a finite difference scheme in time-domain are employed to discretize the governing equations. Firstly the whole ice-melting process on the icicle-shaped icing conductor is simulated by this model. Then the simulated results are validated by ice-melting experiments in the artificial chamber. The study from the model and the experiments shows that the size and length of icicle as well as the space between the adjacent icicles are factors to affect ice-melting. With the shorter icicle space, the bigger icicle size and the longer icicle-length, the surface of ice layer is enlarged and then more heat is taken away by the convection and radiation, so the ice melting time will get longer.

关键词： power line icing ice storm ice melting icicle

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Effects of Annealing Temperature on the electrical Conductivity and Mechanical Property of Cu-Te Alloys

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Journal of Wuhan University of Technology(Materials Science) 2007年第1期22卷 88-90页

作者：朱达川 Metallic Material Department College of Material Science and Engineering Sichuan University

The effects of annealing temperatre on the electrical conducitivity and mechanical property of Cu-Te alloys were studied via an AG-10TA electronic universal machine, an SB2230 digital electric bridge, SEM, EDS and XPS. The results show the electrical conductivity increases while the tensile strength fluctuates when the annealing temperature becomes higher because the recrystallization occurs during the annealing process, leading to the density of dislocation decreasing, grain size growing up, but the second phase precipitating sufficiently and simultaneously.

关键词： Cu-Te alloys annealing temperature recrystallization

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A New Fast Optimal Emergency Control Algorithm

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Journal of Electronic Science and Technology 2012年第1期10卷 37-41页

作者： Biao Wang,B.Wang is with sichuan electric power research institute,chengdu 610072.china.Zheng-Hong Wang,Z.-H.Wang is with the Office of Infrastructure,Southwest Petroleum University,chengdu 610072.china sichuan electric power research institute Chengdu 610072China The Office of Infrastructure Southwest Pedroleum UniversityChengdu 610072China

In order to form an emergency control policy table quickly, this paper proposes a fast algorithm of emergency control named ＂micro-step discrete method＂, which is based on the physical meaning of the gradient and the discrete characteristics of emergency control. Then it is improved through the stability criterion, integral step, and micro-step factor. This paper takes generator-shedding as the emergency control measures. As the optimal generator-shedding control is essentially an optimal control problem and the generator-shedding variables are always constant, it is convenient to use the control parameter algorithm to solve the problem, which can calculate the gradient of the transient stability function to control variables.

关键词： Terms---Generator-shedding micro-step discrete method optimal control transient stability.

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基于OPNET的GOOSE网仿真平台的实现

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计算机科学 2011年第B10期38卷 457-458,476页

作者：李琪林范荣全肖红四川电力科学研究院生技部成都610072 四川省电力公司成都610041

随着GOOSE技术在智能化变电站中的广泛应用,对GOOSE的实时性和可靠性等特性的研究就显得非常重要。由于GOOSE结构的复杂性、研究成本等原因,使得传统的实测法不能很好地满足研究需求,而仿真分析法则可以很好地应用于该领域。介绍了一种... 详细信息

随着GOOSE技术在智能化变电站中的广泛应用,对GOOSE的实时性和可靠性等特性的研究就显得非常重要。由于GOOSE结构的复杂性、研究成本等原因,使得传统的实测法不能很好地满足研究需求,而仿真分析法则可以很好地应用于该领域。介绍了一种基于OPNET的GOOSE网仿真平台的搭建方法。该仿真平台可广泛应用于对GOOSE各种特性的分析与研究。

关键词： GOOSE OPNET 仿真平台动态仿真

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Analysis of Severe Ice Accidents and Applied Countermeasures in china

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electricity 2010年第4期21卷 42-46页

作者： Wang Shaohua Zhejiang electric power test and research institute Zhejiang electric power test and research institute

Based on several typical severe ice accidents that occurred in china, this paper summarizes and analyzes the characteristics and causes for severe ice accidents. The results show that the ice accidents occurring in china have such characteristics as long duration, high frequency of occurrences, large coverage area and enormous loss to the national economy, etc. Drastic deterioration of mechanical property and electric property resulting from severe icing is the major cause of ice accidents. Besides, this paper summarizes the preventive measures for transmission lines in case of severe ice accidents.

关键词： transmission line icing galloping anti-icing anti-galloping

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智能变电站GOOSE通信网实时性分析

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计算机科学 2011年第B10期38卷 444-446页

作者：范荣全肖红李琪林四川省电力公司成都610041 四川电力科学研究院生技部成都610072

GOOSE是IEC 61850中定义的一种通用变电站事件模型类,对于实现设备间的互操作具有重要的意义。随着符合IEC 61850的智能变电站技术的快速发展,GOOSE在智能变电站的应用也日益深入广泛。分析了GOOSE通信网的传输机制和在智能变电站中的... 详细信息

GOOSE是IEC 61850中定义的一种通用变电站事件模型类,对于实现设备间的互操作具有重要的意义。随着符合IEC 61850的智能变电站技术的快速发展,GOOSE在智能变电站的应用也日益深入广泛。分析了GOOSE通信网的传输机制和在智能变电站中的工作方式,并采用OPNET仿真软件对GOOSE网的两种拓扑结构的实时性进行了仿真研究和对比分析。

关键词： GOOSE IEC61850 OPNET 实时性

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Torque model of hydro turbine with inner energy loss characteristics

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Science china(Technological Sciences) 2010年第10期53卷 2826-2832页

作者： ZENG Yun1,2, GUO YaKun2, ZHANG LiXiang1, XU TianMao3 & DONG HongKui4 1 Construction Engineering College, Kunming University of Science and Technology, Kunming 650051, china 2 School of Engineering, University of Aberdeen, Aberdeen AB24 3UE, UK 3 Computing Center, Kunming University of Science and Technology, Kunming 650051, china 4 Hydraulic Energy Department, Yunnan electric power test and research institute, Kunming 650217, china 1. Construction Engineering College Kunming University of Science and Technology Kunming 650051 China2. School of Engineering University of Aberdeen Aberdeen AB24 3UE UK3. Computing Center Kunming University of Science and Technology Kunming 650051 China4. Hydraulic Energy Department Yunnan Electric Power Test and Research Institute Kunming 650217 China

This paper presents the result and analysis of the composition of energy loss occurring in the hydro turbine. Two new types of energy losses,namely the hydraulic loss in the flow channel and the impact loss,are defined. All losses within the hydro turbine are divided into four types and the loss coefficients are defined accordingly. Expressions or characteristic descriptions of these losses as well as the calibration method of the loss coefficients are presented. Furthermore,the torque model of the hydro turbine where the inner energy loss takes place is established. The developed model has been used to calculate the power loss due to the mechanical friction generated by the units’ rotation to solve the difficulty of measurements of the mechanical friction loss in the hydro turbine. The definition of the impact loss explains the phenomenon that the loss of no-load is greater than that of the rated operation. A set of conversion coefficients are defined using the characteristic parameters at the rated operation,which are used to transform the parameters in the torque model into those that are easily measured. Therefore,the expression of the hydro turbine power is converted into a function that has the main servomotor displacement as its single variable. This makes the proposed model be convenient to use. Finally,the proposed model and methods are calibrated and verified using the measured data of a hydropower plant. Good agreement between the modeled results and the measurements indicates that the proposed model can represent the inner energy loss characteristics of the hydro turbine.

关键词： hydraulic loss in flow channel impact loss loss coefficients conversion coefficients

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Teaching and Learning Reform of Visual Foxpro Programming

Teaching and Learning Reform of Visual Foxpro Programming

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2010 Second International Conference on E-Learning, E-Business, Enterprise Information Systems, and E-Government (EEEE 2010)

作者： Xiaona Xie 1,2 1Physical Education College of Zhengzhou University Zhengzhou, china 2School of Computer Science and Engineering University of Electronics Science and Technology of china chengdu, china Zhengwei Chang sichuan electric power test & research institute chengdu, china

In order to meet the needs of teaching and learning process of physical education majors, this paper develops a student-centered two-stage teaching method for Visual FoxPro (VFP) Programming course. Sample teaching method is used to learn basic knowledge in the first stage. Then grouping and project-oriented teaching method is used to learn systematic knowledge and programming skills in the second stage. The results of this new teaching method demonstrate that the undergraduates had a positive learning attitude and the course achieves good effects.

关键词： Visual Foxpro Programming physical education college two-stage method sample teaching grouping and project-oriented teaching

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Fault Analysis and Innovation in Slag Discharge System of 440-t/h CFB Boiler

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electricity 2009年第1期20卷 34-37页

作者： Xu Qisheng and Song Jinghui Guangdong electric power test and research institute Wang Ningling Guangdong electric power test and research institute

CFB boilers have been widely used in china in recent years with their perfect performances in coal adaptability, load variation capability and lower pollutant emission. The No.3 135-MW CFB unit in Lianzhou power Plant is the f irst 440-t/h series CFB unit in Guangdong Province. It f inished 72-hour trial operation in Feb. 2004 and was transferred to trial operation. During the trial operation and the next commercial operation, there were some problems happened in the boiler slag discharging system, seriously affecting the safe and reliable operation and the loading capability. After innovation, these problems have been completely solved. Hopefully the solutions may be used for reference to the units with similar problems.

关键词： CFB Fault Analysis and Innovation in Slag Discharge System of 440-t/h CFB Boiler Innovation

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三峡泄滩滑坡滑动带土的Singh-mitchell蠕变方程

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四川大学学报（工程科学版） 2003年第5期35卷 93-95页

作者：王琛唐明刘浩吾高正中四川大学水电学院四川成都610065 四川电力股份有限公司四川成都610021

三峡古滑坡的变形和长期稳定的控制性因素在于滑动带土的力学特性的强度损伤积累和时间效应。为了滑坡建模和稳定数值分析的需要,进行了泄滩滑坡体滑动带土的三轴排水蠕变试验研究,给出了排水条件下粘性土的Singh mitchell蠕变方程,其... 详细信息

三峡古滑坡的变形和长期稳定的控制性因素在于滑动带土的力学特性的强度损伤积累和时间效应。为了滑坡建模和稳定数值分析的需要,进行了泄滩滑坡体滑动带土的三轴排水蠕变试验研究,给出了排水条件下粘性土的Singh mitchell蠕变方程,其中应力-应变关系采用指数函数,应变-时间关系采用幂函数。该方程参数少,能够较好的拟合试验曲线。

关键词：滑动带土蠕变三轴排水蠕变试验 singh-mitchell蠕变方程应力-应变-时间关系

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