2012 Vol. 38, No. 2

Display Method:
Case Analysis of Especially Serious Gas Explosion Disaster Caused by Electric Fire Source
SUN Ji-ping
2012, 38(2): 1-5.
Abstract:
The paper analyzed causes of "9?8" especially serious gas explosion disaster at No.4 Coal Mine of Xinhua District which led to death of 76 people: amount of high-concentration gas accumulated in 201 tunnelling roadway because of roof caving which caused blowing-out of local ventilator of 201 tunnelling roadway; peccant air supply caused gas concentration to explosion limit; cable of coal electric drill of 201 tunnelling roadway lost explosion-proof ability to ignite gas; coal dust participated in explosion. Then it summarized accident lessons: the mine had confused ventilation management, such as small roadway section, thick coal dust, serious air leakage of air door and series ventilation of outburst mine; the mine used wooden support which caused serious roof caving; the mine had confused electromechanical management, such as underground cables had torn shield, electrical equipments lost explosion-proof ability, and maintenance of integrated protectors of coal electric drill did not accord to regulations; the mine did not implement regulations of lock between gas and electricity and between air and electricity; local ventilator had no special power supply and no other ventilator standby; sensors in safety monitoring and control system of the mine were far less than requirements of relevant standards and regulations, and were neither installed in correct sites and nor properly used; when safety monitoring and control system alarmed, the mine took wrong actions with pulling out sensors to avoid supervision other than cutting power and evacuating people. At last, it pointed out that gas control must be done in various aspects of ventilation, monitoring, drainage, power supply, explosion-proof, dustproof, fireproof, blasting and risk avoiding.
Design of Emergency Communication Security System of Coal Mine
QIAN Jian-sheng, LI Shuang-shuang, WANG Ying-ying
2012, 38(2): 5-8.
Abstract:
The paper proposed a design scheme of emergency communication security system of coal mine. The system's core namely emergency rescue software platform integrates underground broadcast telephone, PHS, WiFi mobile phone, dispatching telephone, underground broadcasting system through relay gateway and special converter, so as to realize interconnection among communication systems. And the system can realize interconnection with personnel location system of mine and integrated access with industrial Ethernet of mine through emergency rescue software platform. The actual test result showed that the system has functions of line management, audio playing, push-to-talk, broadcasting and emergency communication rescue, which improves efficiency of emergency rescue work.
Design of Application Management Software of Multimedia Rescue Communication System
LI Wen-feng, TANG Xiao-li, XU Ke-qiang, LU Jun
2012, 38(2): 9-12.
Abstract:
In view of problems of limited information, dispersed storage data and single function of current mine rescue software, the paper proposed a design scheme of application management software of multimedia rescue communication system which can coordinate with front-end device of multimedia rescue communication system to process and store rescue information real-timely. It analyzed design requirements of the software and introduced design of function modules of the software in details, and gave implementing principles of technologies of multimedia information fusion and information retrieval used in the software. The actual application showed that the software has functions of video display and storage, multiparty calls, environmental parameters display and alarming, which meets with requirements of diversified information and rescue information sharing of rescue work.
Implementation of Management Type Switch Based on SMI
HUANG You-sheng
2012, 38(2): 12-15.
Abstract:
The paper proposed a design scheme of management type switch which is configured by embedded micro-controller LPC2368 through SMI. Taking RTL8306E switch as example, it introduced design of hardware and software of interface circuit of RTL8306E and LPC2368 in details. The industrial test result showed that the switch realizes various interface modes of SNMP, TELNET, Web and CONSOLE and reaches design requirements with stable and reliable performances.
Research of Relationship between Reading Card Efficiency and Distance of EPC Gen2 System
TAN Da-ke
2012, 38(2): 16-18.
Abstract:
It was found that influence of distance between label card and card reader on reading card efficiency of EPC Gen2 system is big in application of EPC Gen2 system: signal that some label cards fedback to card reader became too weaker to be identified with increasing of the distance; the signal sent by some label cards with weak reflection signal were more difficult to reach card reader with increasing of the distance when needing simultaneously identify many label cards. Quantized experiments were made for the above problems and got following result: it did not appear situation that label cards were missed reading when distance between label cards and card reader was 3 m and the reading time was short; it appeared situation that some label cards did not be read in 2 min when distance between label cards and card reader was 5 m. The experiment result showed that reading card rate and read rate of EPC Gen2 system decrease obviously with increasing of distance between label cards and card reader, EPC Gen2 system is not suitable for application of long distance and simultaneous identification with higher reliability.
Key Technologies of Explosion-proof Frequency Converter Applied in Coal Mine
ZHU Long-ji, ZHANG Xu-li
2012, 38(2): 19-22.
Abstract:
The paper analyzed problems of voltage level, heat dissipation, EMC and conversion efficiency of inverter existed in using process of explosion-proof frequency converter in coal mine underground, and introduced methods of solving these problems in details, namely using technologies of flameproof and intrinsic safety and heat dissipation with heat pipes to solve problems of explosion-proof and heat dissipation of frequency converter, which can make explosion-proof frequency converter has characteristics of high performance, strong functions and low noise; using technical means of changing circuit topology and improving control strategy of frequency converter to solve problems of EMC and energy consumption of frequency converter, which can make explosion-proof frequency converter meet with requirements of modernization of coal mine production.
Basic Requirements and Design Method of Mine-used Intrinsic Safety Power Supply
ZHU Qian-wei
2012, 38(2): 22-25.
Abstract:
Combining with related requirements of new national standard GB3836.4-2010 and Mining Products Safety Approval and Certification Center, the paper analyzed technical performance of mine-used intrinsic safety power supply, namely electrical isolation method and protection mode of energy-limiting circuit, and introduced main discharge mode and design points of mine-used intrinsic safety power supply according to its technical indexes. It indicated that relations of four parameters of the maximum output voltage, the maximum output current, the maximum external capacitance and the maximum external inductance need to be considered when designing intrinsic safety power supply, and lower maximum output voltage should be selected for gaining the maximum output power. The paper has certain reference for design of mine-used intrinsic safety power supply.
Research of Dispatching Model of Coal Mine Air Compressor Unit
LU Ru-yi, SHI Zhi-peng, HU Zhi-qiang
2012, 38(2): 26-29.
Abstract:
In view of problem of higher electricity consumption of air compressor, the paper proposed an optimal control scheme of air compressor unit, namely building dispatching model of air compressor unit to realize goal of constant-pressure and energy-saving. Optimal control principle of the model is as follows: when pipe network pressure changes, making constant-pressure decision, energy-saving decision and distribution decision for situation of each air compressor in air compressor unit to maintain network pressure in 0.58-0.65 MPa. The test result validated feasibility of the model.
Research of Errors Elimination Strategy of Body Pose of Boom-type Roadheader
DU Yi-bo, MU Jing, LI Rui, LIU Jian-gong, WU Miao
2012, 38(2): 29-31.
Abstract:
The paper proposed an errors elimination strategy of body pose of boom-type roadheader based on detection system of body pose of boom-type roadheader. Control principle of the strategy is as follows: judging pose errors size of each direction according to data collected by detection system of body pose of boom-type roadheader; adjusting boom-type roadheader through controlling track, shovel and support bracket to reduce errors of each direction of body when the errors are big; setting correct position of cutting contour and making automatic cutting according to current pose errors when the errors are reduced to control compensation range of cutting arm; calculating compensation quantity of residual pose errors of each direction and controlling boundary position of cutting section in automatic flitching process according to the compensation quantity. The strategy has certain reference for realizing automatic directional tunnelling and remote control of tunnelling.
Personnel Tracking Method of Coal Preparation Plant Based on Improved MeanShift Algorithm
ZHAI Nai-jiang, LI Cheng-dong
2012, 38(2): 32-35.
Abstract:
In view of problem of object losing because that traditional MeanShift algorithm used in intelligent video monitoring is easy to be disturbed by background, the paper proposed a personnel tracking method of coal preparation plant combining with MeanShift algorithm and Kalman filtering algorithm. The method firstly segments object tracking region through motion detection method, and predicts starting point of next frame tracking window through Kalman filtering algorithm, then uses MeanShift algorithm to track object region on the basis. In order to prevent tracking failure because of complex environment of coal preparation plant, the method combines with tracking and detection to further ensure robustness of tracking. The experiment result showed that the method can eliminate influence of similar color region in background and has better tracking effect.
Application Research of Image Gray Information in Automatic Separation of Coal and Gangue
YU Guo-fang, ZOU Shi-wei, QIN Cong
2012, 38(2): 36-39.
Abstract:
In view of problems of no representation and practicality because that traditional separation system of lump coal and gangue based on image gray information only randomly selects samples of coal and gangue, the paper researched an automatic separation system of lump coal and gangue based on image gray information which emphasized in practicality and system. At first, it selected six representative lump coals and gangues in term of material, texture feature and cleanness, and analyzed distribution law of image gray of the six lump coals and gangues according to certain group mode under conditions of strong light, natural light and energy-saving lamp light and made the distribution law as basis of object recognition of computer, so as to realize automatic separation for lump coal and gangue. The test result showed that using obvious differences of image gray information between lump coal and gangue to make visual distinction can realize automatic separation under special conditions.
Implementation of TFT-LCD Display System with High Gray Levels
SONG Yi-qing, FANG Zhen-dong, SHENG Hui-xing, CHENG Yun
2012, 38(2): 40-43.
Abstract:
The paper proposed a design scheme of TFT-LCD display system with high gray levels which takes FPGA as core controller. The system uses mixed gray modulation method of amplitude-FRC-space, which segments 10 bit R, G, B signal into high 8 bit data and low 2 bit data, and the low 2 bit data processed by space process are assigned to four adjacent 8 bit data equally, then the 8 bit data are segmented into high 6 bit data and low 2 bit data, and the high 6 bit data are used for amplitude modulation, the low 2 bit data are used for FRC, so as to realize 1 024 gray levels display. The test result showed that the system has good display effect with high display gray levels.
Research of Influence of Change of Load Dynamic Characteristics on Static Voltage Stability of Power System
DUAN Jun-dong, HUANG Jia-xing
2012, 38(2): 44-48.
Abstract:
In view of problems that load dynamic characteristics excited dynamic change of voltage and would cause voltage collapse under extreme case, the paper introduced slip ratio into load equivalent impedance model to analyze load impedance module and load impedance angle, which obtained catastrophe point of load impedance module and load impedance angle. It analyzed load dynamic characteristics by use of the model and discussed changes of voltage and power of node when load changed, which obtained turning points of node voltage and node power. It analyzed influence of different load proportion on static voltage stability of power system by an example through combining with voltage stability limit curve of transmission network which was deduced by three element voltage stability analysis method,so as to reach a conclusion that increasing proportion of constant impedance load would be helpful to enhance static voltage stability of power system.
Research of Rectification Technology of Electric Locomotive under Unbalanced Three-phase Voltage
LV Kang-fei, SHI Chao-yue
2012, 38(2): 49-52.
Abstract:
In view of problem of negative sequence current component in AC side of traditional PWM rectifier because of unbalanced three-phase voltage existed in converter system of underground DC electric locomotive, the paper proposed a control strategy of restraining negative sequence current component of AC side of PWM rectifier under unbalanced three-phase voltage. It introduced implementation of the control strategy in details. The results of simulation and field experiment showed that current wave of AC side of PWM rectifier is close to sine wave and realizes running with unity power factor after using the control strategy.
Research of a New Criterion of Main Protection of Transformer
HE Ren-wang, XIE Wei, SONG Hai-yan, WU Xun
2012, 38(2): 52-55.
Abstract:
In view of problems that traditional main protection of transformer cannot identify inrush current and internal fault current of transformer, the paper proposed a new criterion of main protection of transformer based on dead angle of differential current. The criterion uses sym4 wavelet transform to process inrush current and internal fault current of transformer and obtains obvious difference characteristics of dead angles of the both under d1 scale, so as to identify inrush current and internal fault current of transformer correctly. The simulation result validated effectiveness of the criterion.
Design of Mine-used Radar Level Meter
SUN Li, LI Qing-zhao, PAN Shou-guo
2012, 38(2): 56-58.
Abstract:
In view of problem of bad precision in measurement of coal level of coal bunker by use of ultrasonic level meter, the paper introduced design of a radar level meter based on radar ranging principle. The meter takes surface radar probe as measurement unit which is reformed to be suitable for mine use, and combines with corresponding power supply module, CPU processing circuit, communication module and output module which meet with requirement of intrinsic safety, and realizes precise measurement for coal level of coal bunker. The test results validated feasibility of the meter.
Application of MapGIS in Mineral Resources Evaluatio
ZHANG Jin-shan, MENG Guo-sheng, SUN Jia-ju, DU Wen-xiu, LI Chen, CAO Yue-hui
2012, 38(2): 59-63.
Abstract:
In view of problem of advanced geology data acquisition method but backward data processing method in mineral resources evaluation, the paper proposed a mineral resources evaluation method based on MapGIS K9. The method firstly builds database of surrounding and deep data of old mine in resource center of MapGIS K9, then uses MapGIS K9 software to process the data to generate coordinate transformation point bitmap and geochemical map, so as to finish process of mineral resources evaluation. The processing result showed that the method not only reduces processed period of mineral resources data but also ensures accuracy of spatial data.
Design of an Intelligent Control System of Mine-used Valve
LIU Yan, MA Wei-hua
2012, 38(2): 63-67.
Abstract:
In view of problem that control requirements of mine-used valve controller become more and more complex, the paper proposed a design scheme of intelligent control system of mine-used valve based on M0516LAN microcontroller. The system is composed of main control module, protection module and display module. The main control module is used as master to communicate with protection module and display module, and controls operation of valve motor; the protection module is used to monitor phase sequence of three-phase AC of valve motor and faults of leakage, open-phase and under voltage to cut off power for valve motor if it is necessary; the display module real-timely displays opening of valve and monitoring result of the protection module on LCD. The actual application showed that the system can control valve real-timely and accurately.
Control System of Belt Conveyor Based on Embedded Technology
XU Xi-yi
2012, 38(2): 68-70.
Abstract:
In view of problems of big volume, inconvenient to change PLC program and high cost in control system of belt conveyor based on PLC, the paper proposed a design scheme of control system of belt conveyor based on embedded technology. It detailedly introduced design of hardware and software of embedded intrinsic safety controller, control driver and remote I/O module of the system. The actual application showed that the system solves problems in control system of belt conveyor based on PLC and has better stability, flexibility and friendliness.
Design of Gateway in Fault Location System of Belt Conveyor
YIN Shao-jie, SUN Jin-sheng, SUN Huai-xiang
2012, 38(2): 71-75.
Abstract:
Taking fault location system of belt conveyor as application background, the paper proposed a design scheme of gateway of CAN bus and Profibus-DP bus based on STM32F103VE. The gateway is used as a CAN communication node in CAN network and a slave station in Profibus-DP network. Several CAN detection nodes are distributed along belt conveyor and each node is used to detect real-time data collected by four kinds of sensors. If fault is detected, CAN detection nodes would send fault message to the gateway which receives and stores message sent by CAN detection nodes. When the gateway is connected with Profibus-DP master station, the gateway is used as Profibus-DP slave station to send fault message to Profibus-DP master station through query mode to realize fault location function. The actual application showed that the gateway runs stably and reliably and realizes interconnection between CAN bus and Profibus-DP bus of fault location system of belt conveyor.
Design of Monitoring System of Underground Coal Feeder
CHEN Yong-ran, ZHANG Hai-tao, LI Wei, MENG Guo-ying
2012, 38(2): 75-77.
Abstract:
In view of problem of strip break of belt caused by overload of coal feed rate of underground coal feeder in a coal mine, the paper proposed a design scheme of monitoring system of underground coal feeder. It expounded hardware structure and software design of the system and introduced installation of hardware devices and debugging steps of software modules of the system. The actual application showed that the system improves reliability of coal feeding system.
Design of Gas Drainage Pipeline System and Selection of Its Equipments
LI Gou-xiong, SUN De-ning, WANG Hong-cun, XIE Xiao-ming, LIU Wei-cheng
2012, 38(2): 78-81.
Abstract:
Taking practice of building gas drainage system at a high gassy mine as example, the paper introduced design of gas drainage pipeline system in gas drainage system, namely design of laying line of pipeline, selection of gas-suction diameter and calculation of pipeline resistance, and gave selection design of gas-suction pump according to calculating result of pipeline resistance and selection principle of gas-suction pump. The actual application showed that the coal mine has not appeared phenomenon of disallowed gas concentration with 46% gas-suction rate after using the gas drainage system.
Design of Mined-used Video Monitoring System Based on DaVinci Technology
ZHU Tao, HU Song
2012, 38(2): 81-83.
Abstract:
In view of problems of bad stability and high cost in traditional mine-used video monitoring system by use of DSP+ARM scheme, the paper proposed a design scheme of mine-used video monitoring system based on DaVinci technology. The system takes DaVinci platform based on dual-core chip DM6446 as core. DSP core uses MPEG4 algorithm to compress and code video information collected by simulated camera, then the coded video data is transmitted to ARM core through internal channel of DaVinci platform. ARM core sends the coded video data to server through UDP network and the server receives the data and makes decode and play, so as to realize video monitoring function under DaVinci platform. The experiment result showed that the system has higher reliability, but it need make a lot of field tests for coal mine use.
Research of Mine-used Blending Device of Emulsion Concentratio
WU Yong, SONG Lei, QU Nai-rui
2012, 38(2): 84-87.
Abstract:
The paper analyzed working principle of traditional mine-used blending devices of emulsion concentration and theirs problems of blending precision and costs, and introduced design of a reciprocate type blending device with single-piston which does not need explosion-proof design. The device makes emulsion concentration blending according to fixed area ratio which can make emulsion concentration be not influenced by change of water pressure and other external parameters, and it has high blending precision. The device does not need extra hydraulic pump and motor with low production costs, and it belongs to pure hydraulic device, so it does not need explosion-proof design. The test result showed that the device runs stably and each index reaches design requirements.
Design of Frequency-conversion Speed-regulation System of Emulsion Pump Statio
XU Bing, ZHOU Hai-yan, SHI Xi-yang, SUN Jia
2012, 38(2): 87-89.
Abstract:
In view of problem of higher mechanical loss existed in traditional speed-regulation system of emulsion pump station, the paper proposed a design scheme of frequency-conversion speed-regulation system of emulsion pump station. It gave hardware structure of the system and introduced working mode and software design of the system in details. The actual application showed that the system has stable running and low mechanical loss.
Design of Monitoring System of Hydraulic Weight-fixed Loading Based on PLC and LabVIEW
YAO Lian-jie, ZHENG Chang-xiang, BI wei, REN Guo-hua
2012, 38(2): 90-92.
Abstract:
In view of problem of non-ideal application effect of piezomagnetic weight-fixed device used in skip hoisting, the paper proposed a design scheme of monitoring system of hydraulic weight-fixed loading based on PLC and LabVIEW. It gave working principle of hydraulic weight-fixed loading, and detailedly introduced design of hardware and software and communication implementation between LabVIEW and PLC. The actual application showed that the system is suitable for field application with stable and reliable running.
Design of Data Collection System of Dynamic Electronic Railway Scale
XU Dong, XU Hai-xian, CUI Ting-ting
2012, 38(2): 92-95.
Abstract:
The paper proposed a design scheme of data collection system of dynamic electronic railway scale and mainly introduced hardware design of weighing channel which influences performance of the system. The system uses AD625 and second-order low-pass filtering circuit to make primary process for sensor signal, and uses PCI-8325B to realize AD conversion for the processed data and sends the data to front host to make software process through PCI bus, then sends the data to terminal computer through network bridge or Modem to realize unified management for the data. The test result showed that the system meets with actual application requirements of object.
Power Supply Design System of Mining Area Based on AutoCAD
WANG Jun-fei, ZHAO Chun-yu
2012, 38(2): 96-98.
Abstract:
In view of problems of separation of drawing and calculation, setting calculation lagging behind change of field power system existed in traditional power supply design system of mining area, the paper proposed a design scheme of power supply design system of mining area based on AutoCAD. The system uses embedded VBA of AutoCAD platform to make secondary development, and compiles program to extend functions of AutoCAD to realize integration of drawing, calculation and file management of power supply design by one software. The actual application showed that the system has characteristics of good interaction, convenient operation and high reliability.
2012, 38(2): 98-102.
Abstract:
Design of 16-channel Ethernet Tester
DONG Shi-hu
2012, 38(2): 103-106.
Abstract:
In view of problems of narrow band width and inconvenient operation in traditional Ethernet tester by use of ping packet method, the paper proposed a design scheme of 16-channel Ethernet tester based on C8051 single-chip microcomputer and FPGA module. The tester supports 16-channel Ethernet test, and its FPGA module can provide 16-channel external SMII, whose sending unit is used to receive configuration data of C8051 single-chip microcomputer and send corresponding Ethernet packet according to the configuration data, and receiving unit is used to detect and statistic received Ethernet packet and send the statistical information to C8051 single-chip microcomputer. The test result validated feasibility of the tester.
Design of Measuring Instrument of Impact Frequency of Pneumatic Anchor Drill
DING Jun-feng, ZHANG Sheng-qiang, CHEN Qing-qing, ZHENG Feng-long
2012, 38(2): 106-108.
Abstract:
In view of problem that it is difficult to measure impact frequency of pneumatic anchor drill, the paper proposed a design scheme of new type of measuring instrument of impact frequency of pneumatic anchor drill. The instrument uses pressure sensor to collect impact signal of drill, and uses voltage comparator and monostable trigger to process the signal which is input into single-chip microcomputer to count impact frequency of drill. The actual application showed that the instrument can measure impact frequency of drill accurately and easily.