Chen X.,Fujian Electric Power Survey and Design Institute |
Du M.,Fujian Key Laboratory of Medical Instrumentation and Pharmaceutical Technology
2012 5th International Conference on Biomedical Engineering and Informatics, BMEI 2012 | Year: 2012
In this work we describe the design and engineering of a multi-channel adaptive electrochemical (EC) signal acquisition system both using Field Programmable Gate Array (FPGA) and Field Programmable Analog Array (FPAA). With inheriting the powerful properties from the above devices, it has both automatic gain and reconfigurable feature. The 16 uniform automatic gain control (AGC) modules in this system operate in parallel and set the gain automatically dependent on the input amplitude. Compared with most of the other AGC systems, the combined FPGA/FPAA implementation presented here operates without ADC sampling and software processing, so that the gain-setting time is minimized. Besides, the FPAA-based AGC system can be dynamically reconfigured for polymerase chain reaction (PCR) in future design without changing any hardware. For the simple but efficient control mechanism, most circuits of the system can be integrated into a small-scale FPGA chip and several FPAA chips. These characters make this detection system ideal for in-situ or field multi-channel EC-PCR measurements. © 2012 IEEE.
Fang Y.-L.,Fujian Electric Power Survey and Design Institute |
Lu Z.,Fujian Province Power Dispatch and Communication Center |
Song F.-H.,Fujian Province Power Dispatch and Communication Center |
Xia K.-Q.,NARI Group |
Qi Z.,NARI Group
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2013
In order to meet the construction of regulation integration system and improve intelligent fault information analysis system of relay protection in power grid, this paper designs a practical implementation scheme for relay protection and intelligent fault analysis system. In the proposed scheme, models of primary device and secondary device are unified based on integrative information platform and hierarchical distributed structure. Fault recorder data is uploaded by different channels, in main substation side, fault diagnosis and analysis is made based on multi-source information in EMS, fault information system and fault recording system. Furthermore, a compatible solution is also put forward for the transitional stage of intelligent fault information analysis system. The system has been run in Fujian Power Grid, and the operation status show that the intelligent analysis of relay protection fault information system can be achieved well, providing reference for construction of power system fault information intelligent assistant-decision-making system.
Chen X.-X.,Fujian Electric Power Survey and Design Institute |
Zhang P.-Y.,Fujian Electric Power Survey and Design Institute |
Ding S.-J.,China Electric Power Research Institute |
Tang Z.-Q.,State Grid Corporation of China
Yantu Lixue/Rock and Soil Mechanics | Year: 2015
This paper presents the estimation and measured data analysis of the jacking force of a 3D curved pipe with 3.8 meter external diameter and 413 meter long distance. The jacking force consists of the face load and friction resistance; and it is influenced by many factors. The most widely used estimation methods of the jacking force include Chinese cord method; Japanese method and German method; but they all have specific application conditions, which make them have limitations for engineering application; especially when the friction resistance factors are offered by a wide interval. The jacking force are calculated by the above estimation methods in a 3D curved, 413 meter long distance and 3.8 meter external diameter jacking project, 3 intermediate jacking stations are set according to the calculation results. According to the site measuring data during the construction procedure, the composition of the jacking load and its relationship with the jacking distances and the curve radius are analyzed; and the site measured values of frictional coefficient are offer in table. Base on the analysis results, additional frictional coefficient of axis curve pipe jacking is truly exist, and there are deviations between the cord recommended values and the site measured values. but according to this project, the cord recommended values could meet the demands of scheme design in clay or in silt clay. At the end of this paper, suggestions of the jacking force estimation and intermediate jacking station arrangement are proposed, which provide references for similar construction. ©, 2015, Academia Sinica. All right reserved.
Xia C.,Tongji University |
Chen X.,Tongji University |
Chen X.,Fujian Electric Power Survey and Design Institute |
Xu C.,Tongji University |
Zhao X.,Tongji University
Yanshilixue Yu Gongcheng Xuebao/Chinese Journal of Rock Mechanics and Engineering | Year: 2010
Jinjishan tunnel in project of Fuzhou airport expressway construction is multi-arch tunnel with eight lanes in China. In surrounding rock of the tunnel, joints were developed which cut the original rock blocks into even smaller blocks. The blocks can be easily disturbed and become unstable during tunnel excavation. To keep the blocks stable is one of the most important problems in construction of the highway tunnel. Data of joints unveiled during excavation in several cross-sections of mid-drift of the tunnel and other areas are collected in detail and described meticulously. Based on statistical analysis of the data, distribution of joints in whole face tunnel relative to the same cross-section is forecasted. The block theory is adopted to study the location, volume, sliding force, safety factor and other parameters of key blocks in the cross-sections of whole face tunnel. Mechanical calculations of stability are performed to analyze the key blocks in different situations which are the none of reinforced situation, reinforced by anchors situation, and reinforced by anchors and shotcrete situation. The situations are evaluated and advices are made for the engineering application of the tunnel.
Lin S.Y.,Fujian Electric Power Survey and Design Institute
Applied Mechanics and Materials | Year: 2014
Nowadays the application of extremum seeking controller in various engineering industry has attracted a high research attention. Also, it is one of the best known maximum power point tracking algorithm. It can drive the output to its extreme point automatically and dynamically stabilize around the equilibrium. In this paper, it is implemented via Matlab/Simulink. The extremum seeking control scheme controls the wind turbine to operate at its optimal rotational speed adaptively. Piecewise constant input wind will be applied. © (2014) Trans Tech Publications, Switzerland.
Chen X.,Fujian Electric Power Survey and Design Institute
Dianli Zidonghua Shebei/Electric Power Automation Equipment | Year: 2011
The new technologies for the true unattended operation of 500 kV smart substation are expounded, including intelligent primary equipment, networked secondary equipment, IEC61850-based standard substation automation system with advanced applications, online equipment monitoring & conditional maintenance system, remote video monitoring system, intelligent AC/DC power supply system, intelligent inspection system, etc. The technical enhancement of equipment and the systematic optimization of management are the main points in the implementation of true unattended operation. The operational management mode of 500 kV smart unattended substations is put forward: the irregular maintenance patrol of control center plus the intelligent inspection system of substation.
Lin R.,Fujian Electric Power Survey and Design Institute |
Chen Y.-Q.,Fujian Electric Power Survey and Design Institute |
Jiang X.-L.,Chongqing University
Gaoya Dianqi/High Voltage Apparatus | Year: 2010
To provide theoretical basis for the estimation of ice thickness in anti-icing design and icing mechanism study of transmission lines, this paper proposed a thickness prediction model of rime ice accretion on a conductor. This model can be used to describe the capture process of super-cooled droplets by the conductor and the heat-balance state. Simulation results indicate that the collision coefficient and the ice density are the key factors to affect the accuracy of prediction; with the increase of icing time, all the increasing rate of rime ice thickness, the collision coefficient, the collision velocity of droplet and conductor, the density of the rime ice, and the temperature on ice surface gradually diminish. A measurement device based on rotating multicylinder was developed, and an experiment was conducted. Both simulation and experiment results show that the ice thickness decreases exponentially with the increase of cylinder diameter.
Deng H.,Tongji University |
Zhang J.,Tongji University |
Shuai Q.,Tongji University |
Chen Q.,Fujian Electric Power Survey and Design Institute
Dianwang Jishu/Power System Technology | Year: 2010
The high frequency force balance (HFFB) test in wind-tunnel for both models of steel tubular transmission tower, whose type is SZT2, and its cross arms adopted in 1000 kV power transmission project from Huainan to Shanghai, and the mean wind load acting on the models and corresponding pressure coefficients are obtained. Test results show that the least favorable wind direction angles for steel tubular transmission tower are 15° and 75°; the pressure coefficient of 0.80 for steel tubular tower body and that of 0.85 for steel tubular cross arms can meet design requirements.
Huang X.-F.,Fujian Electric Power Survey and Design Institute
Gaodianya Jishu/High Voltage Engineering | Year: 2010
OPGW which is grounded at every tower causes more energy losses. Energy losses can be reduced largely by the improved grounding methods of OPGW which is grounded at one single point in one line section or insulated entirely in whole line. Taking a 500 kV double circuit transmission line on the same tower as an example, we used the improved grounding method of OPGW to analyze and calculate the related induced voltage and circuit parameters in normal, fault and maintenance conditions, and presented the type selection and assembly method for these special components. Analysis of each component in OPGW line system indicates that the OPGW line system adopting the improved grounding method can be achieved approximate safety and reliability level of the OPGW line system which is grounded at every tower. Therefore, the improved grounding method of OPGW is technically feasible and is of a positive significance to construction of "energy-saving, environmental protection" transmission line.
Lin C.-W.,Fujian Electric Power Survey and Design Institute |
Zhuo Z.-J.,Fujian Electric Power Dispatching Center |
Zhou J.,Fujian Electric Power Survey and Design Institute |
Liu Z.-W.,Fujian Electric Power Survey and Design Institute |
Lin D.-Y.,Fujian Electric Power Survey and Design Institute
Dianli Xitong Baohu yu Kongzhi/Power System Protection and Control | Year: 2010
Aiming at the technical difficulties of modifying setting value without blackout, this paper brings forward detailed solutions. Through analyzing the equipment situation of Fujian power grid, it compares several programs for remote verification and modification of the setting value without blackout, then recommends utilizing substation computer monitoring system to realize remote verifying and modifying setting value. In addition, it introduces main function, detailed process, equipment configuration and security measures of the remote modification and verification system of the setting value.