Suggestions to strengthen development and utilization of coal and coalbed methane in Xinjiang
YAN Lu-guang, ZHAO Zhong-xian, WU Cheng-kang, CHEN Jun-wu, FEI Wei-yang,
ZHOU Xiao-xin, DAI Jin-xing, CAI Rui-xian, LIU Jia-qi, XIA Xun-cheng, ZHOU Feng-qi, CHEN Yong, WU Jia-chun, WANG Jun-min, GAO Zhuang, LV Shao-qin, CHEN Xiang-sheng, HU Guo-yi, SUN Yu-han, HU Wen-kang, ZHAO Dai-qing, HUANG Chang-gang, MA Yang,
LIU Feng-song, SHEN Yi-min
(Academic Divisions of Chinese Academy of Sciences, Beijing 100864, China)
Abstract: During the first half of 21st century, to establish the sustainable development system of energy in China it is necessary to change the primary energy structure with significant reduction of the fossil energy percentage and enhance the percentage of renewable. Xinjiang is a region abundant both in non-hydro renewable and fossil energy resources. It is necessary to raise its position on Chinese energy development and to become an important integrated energy base in future. Xinjiang is abundant in coal resource too. Its development and utilization are on good groundwork, but up to now it mainly satisfies its own requirements for social and economic development in Xinjiang only. It has not been planned to be an important coal base of the country yet. 
Academic Divisions of Chinese Academy of Sciences decided to organize academicians and experts to work with consultation study on “Study on Development and Utilization of Coal and Coalbed Methane and Integrated Energy Base in Xinjiang”. Study were divided into 5 subjects:1. resources of coal and coalbed methane in Xinjiang and its development prospect; 2. status of Xinjiang coal in China energy development; 3. development and utilization of Xinjiang coal－output of electricity and export from Xinjiang Uygur Automonous Region to outside; 4. to promote development of coal-chemical industry in Xinjiang in steady steps; 5. exploration, development and utilization of coalbed methane in Xinjiang.
　  In this paper the study results were presented briefly and main suggestions were included.
Key words: Xinjiang; coal; coalbed methane; development; utilization
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 1—5.

Organic fuel synthesis from atmospheric carbon dioxide and hydrogen produced from water by electrolysis
David JOHNSTON
(Power and Energy Research Group, School of Engineering, University of Northumbria at Newcastle,
Newcastle upon Tyne, NE1 8ST, UK)
Abstract: Synthesis of organic fuels from carbon dioxide and hydrogen is analysed, in terms of energy recovery efficiency, and the required energy input for electrolysis of water. This electrical energy is related to the thermal energy required in a power station. A method is described to recover heat from energy-producing reactions in the fuel synthesis process, which can then be used to reduce the electrical energy requirement for electrolysis. By co-locating the fuel synthesis plant with a thermal power station, primary (thermal) energy can be used to produce high temperature steam, with a lower electrical requirement for electrolytic production of hydrogen. This can make more efficient use of the primary energy than a thermodynamic engine. Comparison is made with alternative fuels, in terms of energy budget, sustainability, carbon dioxide emissions, etc. The energy security benefits of advanced fuel synthesis are also identified. 7 Refs. In English.
Key words:  organic; fuel; carbon dioxide; hydrogen; electrolysis
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 6—10.

Research on arc erosion of AgMeO contact
with low voltage resistive load and small current at 50Hz and 400Hz
LI Jing ^1，2， MA Zhi-ying ²
（1. Hunan Institute of Engineering, Xiangtan 411101, China ;  2. Xi’an Jiaotong University, Xi’an 710049, China）
Abstract: Using the electronic analytical balance, SEM and EDS, this paper measures and analyzes the changes of CAgCdO15 and AgSnO2 In2O3 contacts material’s surface profile and constituent during the test process with low voltage resistive load and small current at 50Hz and 400Hz. The paper also discusses the corrosion mechanism of the AgMeO contact materials at 50Hz and 400Hz. 10 Refs. In Chinese.
Key words: 50Hz; 400Hz; resistive; AgMeO; contact materials; arc resistence erosion
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 11—14.

Three phase alternating spiral channel magnetohydrodynamic propeller
JING Yan，MA Xiu-juan，XU Cheng-bin
(School of Information Science and Eng., Harbin Institute of Technology at Weihai, Weihai 264209, China)
Abstract: This paper puts forward a new kind of alternating magnetohydrodynamic propeller structure，which is a three phase alternating spiral channel magnetohydro-dynamic propeller. Under the situation that the magnetic field boundary condition is given，the magnetic field distribution of spiral channel is analyzed. On this foundation，the relation is deduced among the electromagnetic force，electro- magnetic power，electromagnetic efficiency of the propeller and all kinds of parameters. Finally, the advantages of this propeller are discussed with alternating magnetohydrodynamic propeller that has already put forward. 6 Refs. In Chinese.
Key words: alternating; spiral channel; magnetohydrodynamic propeller; amphoteric ion exchange membrane
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 15—17.

Research on torque ripple calculation of LCI fed synchronous motor drives
WEI Qing, SUN Kai, HUANG Li-pei
(State Key Lab of Power Systems, Dept. of Elec. Eng., Tsinghua University, Beijing 100084, China)
Abstract: Load commutated inverter (LCI) fed synchronous motor drive is still widely used today in large scale variable speed applications such as blasters and pumps. However magnetic torque ripples caused by current harmonics is a serious problem in such systems. The traditional time domain method can compute the torque harmonics but costs a long time and it’s hard to get the torque spectrum. This paper builds the mathematical model of 6-pulse LCI fed synchronous motor drive system in frequency domain using the modulation theory. Based on the model, the current and torque ripples can be easily computed. According to the feature of normal LCI drive systems, the model is further simplified, which will largely shorten the computing time but without causing an evident error. Computing results show that the proposed method has a good computing accuracy and a much faster computing speed than the traditional time method. 6 Refs. In Chinese.
Key words: load commuted inverter; current harmonics; torque ripples; modulation theory
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 18—22.

Effect of rail geometrical parameters on inductance gradient of EML
ZHOU Yuan^{1, 2, 3}, YAN Ping¹, YUAN Wei-qun¹, SUN Li-qiang¹
(1. Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China;
2. Graduate School, Chinese Academy of Sciences, Beijing 100049, China;
3. School of Automation and Elec. Eng., Tianjin University of Technology and Education, Tianjin 300222, China）
Abstract: This paper investigates how the thickness and width and other geometrical parameters of rails together with separation between them affect the inductance gradient ( ) of railgun.　 plays an important role in the performance of an electromagnetic launcher (EML), and it determines directly the force that accelerate projectile. Several possible section figures of rail in railguns are discussed respectively, including rectangle section, T-shape section, annular section, and waxing moon section. Also, various figures and various dimensions are tabulated and compared. A finite-element method is discussed to simulate a three-dimensional railgun in this study. Models of 3-D finite element simulations using Ansoft-Maxwell software are performed for the various w, h, R, e, θ, and s values. Values for different geometrical parameters are calculated and compared. It is concluded that to increase L′, the thickness, width and other similar kind of dimensions of rails must be decreased whereas separation between rails ought to increase. In rectangle section rails, the value of inductance gradient will increase as the ratio of w/h increases.
Key words: EML (electromagnetic launch); inductance gradient; rail parameters; finite-element method (FEM)
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 23—27.

Relationship between flashover and inner electrode diameter
under nanosecond pulsed coaxial electric field
HUANG Wen-li^{1, 2}, SUN Guang-sheng², LIU Shun-xin¹, HE Lin-lin¹
(1. Zhengzhou Institute of Aeronautical Industry Management, Zhengzhou 450015, China;
2. Institute of Electrical Engineering of CAS, Beijing 100190, China)
Abstract: Under nanosecond pulsed coaxial electric field, surface flashover voltages for both nylon 1010 and polymethyl methacrylate (PMMA) in transformer oil increased with the inner electrode diameter and then were saturated, and the larger is the inner electrode, the closer is the flashover voltage induced between them. Surface flashover properties were closely related to the electric field at the triple junction of solid-liquid-electrode and the field gradient along the interfaces between solid and liquid, so that the larger is the inner electrode diameter, the higher flashover voltage is owed to resultant depressed field strength at triple junction and the averaged potential distribution along interfaces. If inner electrode diameter value was far largeer than outer electrode diameter’s, the influence of inner electrode diameter on flashover voltage would be weakened for nanosecond pulsed coaxial electrodes. 8 Refs. In Chinese.
Key words: nanosecond pulses; coaxial electrodes; surface flashover; triple junction points; surface potential
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 28—31.

Simulation of work characteristics of a new refrigerant VxF4310 in inner evaporative cooling system of 300MW turbine generator
DONG Hai-hong, GU Guo-biao, FU De-ping, YU Shun-zhou, GUO Jian-zhong
(Institute of Electrical Engineering CAS, Beijing 100080, China)
Abstract: Some new refrigerants are sought and researched to be substitutes for R113, as the coolant in the evaporative cooling generator. The aim of this paper is to analyze the work characteristic of VxF4310, a new refrigerant, in 300MW turbine generator stator by simulation. The variation tendency of pressure drop, temperature changing and etc., under different work conditions were analyzed. From the analysis and the discussion, it can be concluded that the application of VxF4310 is feasible theoretically and fulfills the cooling requirement of the 300MW turbine-generator stator. The conclusion will provide the theoretical basis for the design of actual application in the future.
Key words: evaporative cooling; new refrigerant; work characteristics; simulation
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 32—35.

Feasibility study on small-scale superconducting magnets with fast discharge
LI Feng, DONG Liang, YAN Zhong-ming, XIAO Guang-da, YAN Qiang-hua, WANG Yu
(Superconductivity R & D Center, Southwest Jiaotong University, MOE Key Lab of Maglev Technology and Vehicle, Chengdu 610031, China)
Abstract: When talking about the quench protection of the low TC superconducting magnets, the normal discharge of the magnets can not fulfill the requirement of quick energy-transfer when the quench is happening, and this may be a hidden trouble to the magnets. It is therefore very important for us to investigate the speedy discharge of the pulsed superconducting magnets which can change it’s magnetic flux fastly. The paper discusses two methods of keeping the voltage constant. Comparing with the familiar ways, these methods can evidently improve the speed of the discharge, and the energy-transfer efficiency becomes higher. 10 Refs. In Chinese.
Key words：superconductivity；energy transfer；isobarically discharge；superconducting magnet
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 36—39.

Analysis of fundamental frequency ferroresonance based on theoretical study and simulation method
WANG Wei，JI Sheng-chang，ZHANG Jin，CAO Tao，OU Xiao-bo，LI Yan-ming
（Department of Electrical Engineering, Xi’an Jiaotong University, Xi’an 710049, China）
Abstract: Fundamental frequency ferroresonance frequently occurs in the power system, the overvoltage and overcurrent generated by ferroresonance will endanger the facilities in the power system, and they are harmful. Theoretical method is used in this paper to study fundamental frequency ferroresonance in a typical circuit in which ferroersonance may occur. Nonlinear curve is used to represent the magnetization characteristic of nonlinear inductor, resistance in the circuit is considered, the method used for calculating the critical value of the system’s parameter which will generate ferroresonance is presented, and simulation is done to verify the result obtained by theoretical method. The results show that fundamental ferroresonance can be efficiently analyzed by the theoretical method used in this paper, and it is helpful for the power system design. The lower the iron losses, the higher the source voltage, the smaller the circuit resistance, the smaller the circuit capacitor, and the higher possibility ferroresonance happens.
Key words：fundamental frequency；ferroresonance；theory analysis；nonlinear
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 40—44.

A simplification method to calculate inductance of PCB conductor
CHEN Ming, SUN Xu-dong, HUANG Li-pei
 (State Key Lab of Power Systems, Dept. of Elec. Eng., Tsinghua University, Beijing 100084, China)
Abstract: In order to calculate the inductance of printed circuit board (PCB) conductor of irregular shape by analytic expression, it is necessary to simplify them to ones of regular shape. In this paper, a simplification method is proposed and applied to the power bus conductors in the main board used in the outdoor unit of a variable frequency air conditioner. The analytic solutions of the inductances obtained after simplification are compared with the ones calculated by electromagnetic field numerical calculation software to verify the effectiveness of the simplification method. With the same input voltage in the equivalent circuit model of the DC bus conductors, a comparison is made between the simulation and measurement results of the response voltage. The good agreement between them validates that the parameters of PCB conductors after simplification are exact enough to simulate the performance of coupling path in it, and the proposed simplification approach for the PCB conductors of irregular shape is simple and convenient, thus it has a great value in practical applications.
Key words: PCB, inductance, electromagnetic field numerical calculation
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 45—49.
 
Dynamic analysis on stress of overhead bundle conductor
LEI Ming¹, LIU Gang¹, YANG Ting²
(1. South China University of Technology, Guangzhou 510640, China;
2. China Southern Power Grid Company, Dongguan523000, China)
Abstract: In order to better assess the level of over-current affects on arranged wires elongation and wire spacing, the interaction mechanism between wire spacing and the electromagnetic force is studied. Through the establishment of the parabola model for a transmission line, the model is used to calculate wire electromagnetic force, wire length, wire tension stress and to analyze the effects of factors of current and tensile stress on wire stretch and spacing. Then the use of numerical simulation software obtains the smallest wire spacing in different situations, and analyzes the effects of current of conductor on the shortest distance. By the use of the above comprehensive analysis, the dynamic model of elongation under the over-current is established. Based on the above analysis we can see: a variety of factors can have the effects on the elongation and minimal space, and electromagnetic force and elongation have mutual effects on each other; dynamic conductor model shows the parameters change in the process, and wire critical conglutination parameters are compared to determine the wire conglutination, and measures to prevent conglutination are proposed.
Key words: over-current; wire conglutination; minimum spacing; dynamic model; critical state; parameters change
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 50—53.

Partial discharge detection system based on very wide bandwidth pulse current method
RUAN Ling¹，GAO Sheng-you²，ZHENG Zhong³，GUI Jun-feng⁴，DU Zhi-ye⁵
（1. Hubei Electric Power Test & Research Institute，Wuhan 430074, China;
2. Dept. of Elec. Eng., Tsinghua University, State Key Lab of Control and Simulation of Power Systems and Generation Equipments, Beijing 100084, China; 3. School of Elec. Eng., North China Elec. Power University, Beijing 102206, China; 4. School of Elec. Eng., Beijing Jiaotong University, Beijing 100044, China; 5. School of Elec. Eng., Wuhan University, Wuhan 430074, China）
Abstract: Partial discharge detection and analysis is widely accepted as an effective method to evaluate the insulation status and to figure out the possible defects and their severeness. Compared with traditional IEC method, the very wide bandwidth pulse current method could get more information about partial discharge, which will be helpful to improve the sensitivity as well as the ability of anti-interference. This paper introduces the partial discharge detection system using very wide pulse current method. The characteristic of current sensor, the pulse separation technology and pulse quantitative determination technology are studied. The high frequency current sensor has the bandwidth of 380MHz and the sensitivity of 16.5mV/mA maximum. The pulse separation technology could distinguish partial discharge signal from noise. The tests are carried in laboratory and field. The results show that it has the advantage of high sensitivity and anti-interference ability, which is very suitable for partial discharge on-site detection and on-line monitoring. 8 Refs. In Chinese.
Key words: partial discharge; very wide bandwidth pulse current method; quantitative determination; current sensor
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 54—57.

Control and testing device for intelligent AC contactor using high-speed camera
CHEN De-wei, ZHANG Pei-ming
(Fuzhou University, Fuzhou 350002, China)
Abstract: This paper chiefly describes a testing instrument using high-speed camera to test the dynamic characteristics of intelligent AC contactor. With this device, the switch-on and switch-off processes of the intelligent AC contactor can be detected dynamically. This device can be used in the research of electrical apparatus for achieving real-time dynamic process control, function optimization and enhancing their properties. It may become the basis for research & development and virtual optimization of the products. 7 Refs. In Chinese.
Key words: intelligent AC contactor; high-speed camera system; dynamic characteristics; intelligent measuring
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 58—61.

Design of high voltage pulsed power supply using storage battery as primary energy source
WANG Yu-wei, CHEN Dong-qun, LI Da, CAO Sheng-guang, YANG Jian-hua, LIU Che-bo
(National University of Defense Technology, Changsha 410073, China)
Abstract: To satisfy the request of field experiment, a more compact and smaller pulsed power supply system using storage battery as primary energy source is designed. The law of the change of the charging current and capacitor voltage and the relationship of the charging efficiency and circuit parameters are gained in the theoretical analysis, which provides the theoretical basis of the design. In order to ensure the safety of operators and to automate the system control, the control system is governed by computer. Some active measures are taken to make sure the control system work reliably, such as isolation of the high voltage circuit and low voltage circuit, optoelectronic isolation, shielding in metal box and so on. The experimental results show that the high efficiency charging is realized and the high voltage pulsed power supply system works reliably. This system has been successfully applied in the study of accelerator of intense charged particle beams and explosively-driven magnetic flux compression generators.
Key words: storage battery; field experiment; high voltage pulsed power supply; charge; capacitor
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 62—66.

Research on rail potential and ground surface potential distribution in heavy loading electric railway
AI Bing, DONG An-ping, WU Guang-ning, ZHOU Li-jun, LEI Dong
(Electrical Engineering College, Southwest Jiaotong University, Chengdu 610031, China)
Abstract: As a result of great traction current and rail-ground leakage resistance in the section of high speed and heavy load electric railway, the higher rail potential can have dangerous effect to persons and equipments. The paper firstly explains the mechanism of the rail potential, analyzes the basic characteristic and proves that the higher rail potential is in high frequency through the actual wave and emulational data. It educes that researching the rail potential measurement system is necessary. Then the collection system, GPS synchronization system, anti-jamming technology are analyzed in detail. Eventually through the analysis of technical and economical feasibility, establishing the rail potential measurement system in high speed and heavy load electric railway is feasible. 15 Refs. In Chinese.
Key words: high speed and heavy load; electric railway; rail voltage; measurement system
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 67—72.

Direct synthesis of hydrogen peroxide using plate-plate type dielectric barrier discharge
ZHAO Bin, LIANG Cui-cui, ZHAO Jian-li, YI Yan-hui, GONG Wei-min, GUO Hong-chen
(Department of Catalytic Chemistry and Engineering & State Key Lab of Fine Chemicals,
Dalian University of Technology, Dalian 116012, China)
Abstract: The effects of dielectric barrier, dielectric thickness and gas gap distance of plate-plate type dielectric barrier discharge (DBD) reactor on the direct synthesis of hydrogen peroxide were studied under ambient conditions. Results show that all the dielectric nature, dielectric thickness and gas gap distance have pronounced effects on the synthesis of hydrogen peroxide. Compared with other dielectric materials studied, quartz is more suitable for hydrogen peroxide synthesizing. Using the appropriate thickness of quartz dielectric and gas gap distance can improve the yield of hydrogen peroxide and energy efficiency of the reactor. When both the dielectric thickness and gas gap are 2.0 mm, and the input power is 9.1 W, the yield of H2O2 and energy efficiency of the reactor can reach 20.6 % and 5.5 gH2O2/kWh respectively.
Key words: hydrogen peroxide; plate-plate type DBD reactor; the yield of H2O2; energy efficiency
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 73—76.

Progress and Statistical Analysis of Journals on Electrical Engineering in China
QIN Jie, LIN Liang-zhen, QI Zhi-ping, MA Yu-huan, SHEN Guo-liao, JING Bo-hong
(Institute of Electrical Engineering, Chinese Academy of Sciences, Beijing 100190, China) // 电工电能新技术.—2009, 28(3).—77～80
Abstract: The paper has introduced the journals on electrical engineering in China in detail, presented its publication year, the distributions for all elec. eng. journals and its core journals, the position and level of the journals, its main journal evaluation indexes, its core journal proportion and inclusion info. by famous international database. The paper offers much information about the journals on electrical engineering in China to readers, and also points out present problems and gives suggestion. 15 Refs. In English.
Key words: journals on electrical engineering in China; progress and status; statistical analysis
// Adv. Tech. of Elec. Eng. & Energy, 2009, 28(2). 77—80.