工矿自动化

Proposal of revision for electrical section of Coal Mine Safety Regulatio

SUN Jiping

2014, 40(4): 1-5. doi: 10.13272/j.issn.1671-251x.2014.04.001

<Abstract>(44) <PDF>(5)

Abstract:
The paper proposed that low-power and non-explosion-proof equipments such as general lighting lamps, equipments and instruments of communication and automation are prohibited to be used in coal mine underground; lighting lamps should adopt LED cold light source and be preferred intrinsic safety type or compound type of other explosion-proof types such as intrinsic safety type and encapsulated type or flameproof type; equipments and instruments of monitoring, communication, surveillance and control used in coal mine underground should be preferred intrinsic safety type, signals transferred among the equipments must be intrinsic safety signals; high-power electrical equipments should be preferred flameproof electrical equipments and wiring chamber and primary chamber of flameproof electrical equipments should be setup independently. It proposed that mine-used communication and signal cable and optical fiber can be coiled down. It proposed that mine-used cable connected with flameproof electrical equipments should be resistant to blast; the mined-used communication and signal cable and optical fiber are prohibited to directly connect with sole flameproof electrical equipments; the mine-used communication and signal cable and optical fiber connected to flameproof and intrinsic safety electrical equipments must be resistant to blast. It proposed that aluminum core cable is prohibited in coal mine underground. It proposed that under-voltage protection and loss-voltage protection for local ventilator should has delay measures; besides sites such as tunneling, exploit and temporary construction, use of local ventilator should be reduced as far as possible; it is prohibited to use local ventilator to dilute gas of upper corner in working face with whole wind pressure ventilation. It proposed that miner lamp should adopt LED cold light source and intrinsic safety type or compound type of other explosion-proof types such as intrinsic safety type and encapsulated type; electricity power transferred among light source and lamp cord (separation of battery and headlight) must be intrinsic safety type; incandescent lamp and other special miner lamps are prohibited to be used in coal mine underground.

Application research of technologies of Internet of Things, big data and cloud computing in coal mine safety productio

MA Xiaoping, HU Yanjun, MIAO Yanzi

2014, 40(4): 5-9. doi: 10.13272/j.issn.1671-251x.2014.04.002

<Abstract>(131) <PDF>(15)

Abstract:
The paper expounded research status of technologies of Internet of Things, big data and cloud computing, and indicated relations of the three technologies, namely the Internet of Things produces the big data, the big data boosts the Internet of Things; the big data needs the cloud computing, the cloud computing increases value of the big data. It researched functions and position of the three technologies in security of coal mine safety production combining with development course of construction of coal mine integrated automation, and proposed relations of the three technologies in security of coal mine safety production: the Internet of Things is technical framework and roadmap of construction of each subsystem of coal mine, the big data is product of construction of Internet of Tings of mine, the cloud computing is technical means for treatment and utilization of the big data. It indicated that monitoring and control system of coal mine safety production based on Internet of Things, big data and cloud computing would be a monitoring and control system with active mode, multi-parameter fusion and pre-warning function, which can effectively improve level of coal mine safety production.

Research of online analytical processing and data mining for production cost of coal enterprises

WU Qiao, LUO Jian, LIN Jinyou

2014, 40(4): 10-14. doi: 10.13272/j.issn.1671-251x.2014.04.003

<Abstract>(38) <PDF>(5)

Abstract:
In view of problems of low accuracy and inadequate decision support existed in analysis and control of production cost of coal enterprises, the paper proposed a design scheme of production cost management and decision support. The scheme uses data market to collect the production cost in whole production range and make real-time collection and assignment for the production cost, and it uses technologies of online analytical processing and data mining to get law and trend hided in internal of the production cost, so as to provide decision support for decision-maker. The actual application shows that the scheme realizes real-time analysis and control for the production cost.

Research of optimization of address assignment for underground wireless sensor networks

WANG Lina, HUANG Yourui, TANG Chaoli, QU Liguo

2014, 40(4): 15-19. doi: 10.13272/j.issn.1671-251x.2014.04.004

<Abstract>(70) <PDF>(4)

Abstract:
For existing problems of underground wireless network topology, namely limited network depth and waste of resources in distributed address assignment mechanism, and address conflicts in stochastic address assignment mechanism, binary address assignment mechanism was proposed, namely optimize the network topology by applying unused addresses to parent nodes or children nodes. The simulation analysis and practical application results show that the binary address assignment mechanism greatly improves success ratio of address assignment, and raises real-time performance and reliability of underground wireless data transmission.

Design of tunnel pressure monitoring system of coal mine based on ZigBee

LI Xuezhe, HU Xingzhi, FENG Xiaohui, ZHANG Youdong

2014, 40(4): 19-22. doi: 10.13272/j.issn.1671-251x.2014.04.005

<Abstract>(65) <PDF>(4)

Abstract:
In view of problems of low measuring precision, bad reliability, bad scalability of nodes and non-automatica uploading, analyzing and processing for measuring results, a tunnel pressure monitoring system of coal mine based on ZigBee was designed. The system uses sensor nodes to realize accurate measurement for tunnel pressure, and measuring result is sent to convergent node which sends the measuring result to surface monitoring computer, so as to realize real-time and reliable monitoring for the tunnel pressure. The test result shows that the system can realize precision measurement for stress of anchor and can upload the measuring result real-timely.

Status and development trend of tunneling equipments of coal drift in China

DING Zhe

2014, 40(4): 23-27. doi: 10.13272/j.issn.1671-251x.2014.04.006

<Abstract>(93) <PDF>(8)

Abstract:
The paper introduced composition and performances of tunneling equipments of coal drift in China, namely roadheader unit, continuous miner unit, digging-bolt unit and full-hydraulic jumbo unit, and analyzed applicable conditions and technology characteristics of the equipments. It indicated development trend of the tunneling equipments of coal drift in China, that is using parallel operation of tunneling and supporting to realize rapid tunneling operation line of digging-bolt unit, using whole section tunneling technology to improve tunneling efficiency, using advanced technologies of automation and informatization to realize unmanned operation.

Processing and filtering analysis of navigation data of underground strapdown inertial navigation system

LIU Xiaowen, WANG Cun, WANG Long

2014, 40(4): 27-31. doi: 10.13272/j.issn.1671-251x.2014.04.007

<Abstract>(47) <PDF>(4)

Abstract:
In view of problems of large errors and low accuracy of positioning technology in coal mine, the strapdown inertial navigation system was introduced into coal mine personnel and equipment for precise positioning and navigation. In order to further improve positioning accuracy of strapdown inertial navigation system, filtering algorithms of extended Kalman filter and unscented Kalman filter for system data were proposed, filtering principles of extended Kalman filter and unscented Kalman filter were analyzed, and formulas and algorithms and filtering effect were simulated. The simulation results show that unscented Kalman filter has less jitter and curve is more smoother, that is, filtered data is closer to real data, and it can reflect accurately coordinate information and its error is controlled within allowable range under precondition of assuming the underground noise is Gaussian white noise, which has a better filtering effect.

Research of routing protocol of wireless sensor network for coal mine goaf

XIA Xu, LI Wanghuai, LI Deng, CHEN Zhigang

2014, 40(4): 32-37. doi: 10.13272/j.issn.1671-251x.2014.04.008

<Abstract>(41) <PDF>(5)

Abstract:
In view of problem that current routing protocols of wireless sensor network based on energy balance are not suit to apply in coal mine goaf, the paper proposed an unequal clustering and energy-balanced routing protocol for coal mine goaf，namely UCEB-CMF protocol. Principle of the protocol is as follows: selection mechanism of candidate cluster-head is optimized to ensure sensor nodes with big residual energy to become candidate cluster-head. Calculating formula of unequal competition radius and competition method of the candidate cluster-head are improved, which adds consideration for distance from cluster-head node to Sink node on basis of consideration of residual energy, so as to realize energy balance. In view of characteristics of being easy to die of sensor nodes in coal mine goaf, a routing algorithm with multipath was proposed, so as to realize persistence of data transmission. The simulation result shows that the protocol can balance energy of sensor nodes effectively and prolong survival time of wireless sensor network, which is suite to apply in coal mine goaf.

Research of classification method of materials and equipments of coal enterprise based on probabilistic neural network

HAN Sai, LU Jianjun, WEI Chen, LIU Zhipeng

2014, 40(4): 38-41. doi: 10.13272/j.issn.1671-251x.2014.04.009

<Abstract>(42) <PDF>(2)

Abstract:
In view of problems of extensive classification, subjective evaluation standard and large calculation existed in materials and equipments management of coal enterprises, a classification method based on probabilistic neural network was proposed. The method takes quantitative sample data of three evaluated indices of degree of supply and demand, degree of value and supply efficiency as input and uses probabilistic neural network to establish material classification model. It uses Matlab to simulate classification results and realizes scientific classification according to importance degree of coal materials and equipments. The actual test results show that the method is scientific and accurate.

Application of fuzzy comprehensive evaluation method in coal mine "six systems"

DU Dawen, WANG Baomin, ZHANG Ji

2014, 40(4): 42-45. doi: 10.13272/j.issn.1671-251x.2014.04.010

<Abstract>(40) <PDF>(3)

Abstract:
A fuzzy comprehensive evaluation method was established by use of fuzzy mathematics theory. From acceptance standard of coal mine "six systems", an evaluation index system of coal mine "six systems" was built by the fuzzy comprehensive evaluation method. The evaluation index system is divided into a number of primary, secondary indicators and veto, and it uses analytic hierarchy process to determine weights of evaluated factors, so as to implement comprehensive evaluation of quality grade for coal mine "six systems". The actual application results verify feasibility of the method.

A fault line selection method of small current grounding system based on wavelet de-noising and improved RBF neural network

WANG Xiaowei, WEI Xiangxiang, HOU Yaxiao, GAO Jie

2014, 40(4): 46-50. doi: 10.13272/j.issn.1671-251x.2014.04.011

<Abstract>(58) <PDF>(4)

Abstract:
The paper proposed a fault line selection method of small current grounding system based on wavelet de-noising and improved RBF neural network. Fault information matrix is obtained after normalization processing for maximum of absolute value of de-noised zero-sequence current, and the matrix is used as input of RBF neural network. Active value of input layer of the RBF neural network is calculated, and when the active value is in preset range, hidden layer and output layer of the RBF neural network are disconnected automatically, and neurons of the hidden layer split. After parameters such as weight, variance and central value of the RBF neural network are adjusted, the hidden layer and the output layer are reconnected and training result is output. Test sets are input into the trained RBF neural network to get fault line selection result. The example analysis result shows that the method cannot be influenced by fault phase angle and grounding resistance with accurate and reliable fault line selection.

Research of transmitter of time-domain induced polarization based on super capacitor storage

ZENG Zhihui , ZHANG Yiming , TAO Haijun, ZHU Xuezheng

2014, 40(4): 51-54. doi: 10.13272/j.issn.1671-251x.2014.04.012

<Abstract>(29) <PDF>(2)

Abstract:
In view of problems of no storage of electric energy and big volume existed in current transmitter of time-domain induced polarization, a transmitter of time-domain induced polarization based on super capacitor storage was designed. The transmitter uses new circuit topology, which makes the super capacitor store energy output by generator when the transmitter is in idle state, and the super capacitor release the stored energy when the transmitter is in working state. The released energy and the generator provide power for load so as to reduce volume of the generator. Meanwhile the super capacitor connects in series with power supply of the generator when the super capacitor releases the energy, which not only do not need boost inductor but also can realize boost function, so as to optimize volume of the transmitter. The simulation and experiment results show that the transmitter has stable and reliable performance.

Analysis of loss distribution for power devices of active neutral point clamped three-level inverter

ZHAO Xia, FANG En, XIA Chenyang, TU Wei, GUO Quanju

2014, 40(4): 55-59. doi: 10.13272/j.issn.1671-251x.2014.04.013

<Abstract>(21) <PDF>(3)

Abstract:
In view of problem of uneven loss distribution of power devices in running process of traditional neutral point clamped three level inverter, this paper introduced working principle and basic modulation strategy of active neutral point clamped three-level topology, analyzed loss characteristics of active neutral point clamped three-level converter. Active neutral point clamped three-level topology uses bidirectional power device to instead of traditional clamp diode of neutral point clamped three level, which can realize purpose of loss equilibrium of power device by selecting appropriate combination of zero voltage condition. The simulation results show that active neutral point clamped three-level topology can balance the loss of power devices, and improve the converter capacity under various typical working conditions compared with the traditional neutral point clamped three level.

Comprehensive energy-saving control of asynchronous motor based on penalty functio

LI Jianhong, ZHOU Lawu, XUE Zhengshan

2014, 40(4): 59-62. doi: 10.13272/j.issn.1671-251x.2014.04.014

<Abstract>(44) <PDF>(3)

Abstract:
In view of problem of non-ideal control effect of energy-saving of existing asynchronous motor, the paper proposed a design scheme of comprehensive energy-saving control device based on penalty function, and established integrated optimization model of energy-saving control device. The device uses dynamic voltage regulation technology in frequency-conversion speed-regulation, and can dynamically adjust terminal voltage and frequency of the motor; it adopts penalty function algorithm to optimize power output, so as to make frequency-conversion speed-regulation system of the motor operate in the best mode, and achieve goal of energy-saving. The Matlab simulation results show that the comprehensive energy-saving control device has advantages of voltage and speed regulating energy-saving, and has good energy-saving effect.

Research of single phase-shift close-loop control for bi-directional full-bridge DC-DC converter

YANG Xiaokang, LI Hequn, GAO Qiaomei, CHENG Hong

2014, 40(4): 63-67. doi: 10.13272/j.issn.1671-251x.2014.04.015

<Abstract>(64) <PDF>(4)

Abstract:
In view of problem of low efficiency of bi-directional full-bridge DC-DC converter based on traditional single phase-shift control, the paper proposed a design scheme of bi-directional full-bridge DC-DC converter based on single phase-shift close-loop control. It analyzed steady characteristics of the bi-directional full-bridge DC-DC converter and detailedly introduced modeling implementation of the bi-directional full-bridge DC-DC converter based on single phase-shift close-loop control. The simulation and experiment results show that the converter has high efficiency and low loss.

Research of method of maintaining high power factor for PWM rectifier

ZHENG Lijun, SHEN Yarui, SONG Jiancheng

2014, 40(4): 68-72.

<Abstract>(45) <PDF>(5)

Abstract:
In view of problem that serious voltage fluctuation underground may affect unit power factor of power supply, variable output DC voltage method was proposed to control DC side voltage of PWM rectifier, so as to ensure the PWM rectifier working with high power factor. Selection of DC side voltage and influence of fluctuating of AC side input voltage in a wide range on AC side input current and power factor were analyzed. Control principle and software implementation of variable output DC voltage method were introduced respectively. The test results show that the PWM rectifier with variable output DC voltage control method can work stably and always achieve high power factor under voltage fluctuations.

Adaptive control method for WSN link based on interference estimatio

CHEN Jie, KAN Baoqiang

2014, 40(4): 72-77. doi: 10.13272/j.issn.1671-251x.2014.04.017

<Abstract>(34) <PDF>(5)

Abstract:
In view of problem that existing transmission power control algorithms of wireless sensor network do not take full account of actual channel interference, calculation method of optimal transmission power based on interference estimation was given. An adaptive rate adjustment algorithm was proposed in consideration of time-varying characteristics of communication channels and the number of active nodes. Finally feasibility of the proposed method was verified through experiments.

Research of coal mine supervision platform based on cloud computing

XU Jin

2014, 40(4): 78-81. doi: 10.13272/j.issn.1671-251x.2014.04.018

<Abstract>(34) <PDF>(6)

Abstract:
In order to solve problems existed in current vertical multistage supervision mode, such as repeated construction, unevenness level, multistage data repeated uploading and data fraud, a coal mine supervision platform based on cloud computing was designed. The platform depends on cloud computing technology, adopts unified data storage strategy and processing mechanisms, and uses multi-network for data transmission combining with basic monitoring terminals, so as to provide specialized services and a new parallel and direct supervision model between supervision organizations and coal mines through strict permissions management and good scalability.

Design of wireless monitoring system of mine ventilator

HAN Tao, HUANG Yourui, QU Liguo

2014, 40(4): 81-83. doi: 10.13272/j.issn.1671-251x.2014.04.019

<Abstract>(46) <PDF>(4)

Abstract:
In view of problems of high cost, complex structure and being not convenient to extend caused by wired communication mode in traditional monitoring system of mine ventilator, the paper proposed a design scheme of wireless monitoring system of mine ventilator based on ZigBee. It detailedly introduced design of hardware and software of the system. The actual application shows that the system has stable running, easy installation and being convenient to extend.

Design analysis of mine-used intrinsic safety power supply

LIU Qi

2014, 40(4): 84-86. doi: 10.13272/j.issn.1671-251x.2014.04.020

<Abstract>(45) <PDF>(8)

Abstract:
In view of requirements that intrinsic safety power supply must has multi-protection of over-current and over-voltage, the paper introduced working principle of a circuit of mine-used intrinsic safety power supply based on LM317 regulator, analyzed design requirements of fuse, filter capacitor and regulator in the circuit, and detailedly introduced calculating method of parameters of circuit of over-current and short-circuit protection and circuit of over-voltage protection. The design of double protection of over-current and over-voltage in the circuit of the power supply provides reference for designing reasonable and reliable intrinsic safety power supply.

A new type of automatic gas distribution system applied in flameproof test devices

JI Xiaohua, WANG Zhiming

2014, 40(4): 87-89. doi: 10.13272/j.issn.1671-251x.2014.04.021

<Abstract>(34) <PDF>(4)

Abstract:
In view of problems of slow speed of gas distribution, big volume of system of traditional gas distribution methods applied in flameproof test devices, an automatic gas distribution system based on mass flow method was designed. The system uses mass flow controller to control flow of several different gases accurately, and the output gases are mixed uniformly by mixed equipment. Volume fractions of the mixed gases are monitored real-timely by oxygen analyzer and hydrogen analyzer. The test result shows that the gas distribution system has fast speed of gas distribution and simple structure, and precision of the volume fractions of the gases distributed by the system can meet requirements of GB 3836.2-2010.

Design of database of mine logistics management system based on RFID technology

HE Yaru

2014, 40(4): 90-92. doi: 10.13272/j.issn.1671-251x.2014.04.022

<Abstract>(41) <PDF>(6)

Abstract:
The paper analyzed working principle of mine logistics management system based on RFID technology and determined functions requirements of the system, namely functions of basic data management, logistics business management, logistics transportation monitoring and data statistics. It detailedly introduced design implementation of conceptual structure, logic structure, processing of key data, safety and electronic tag coding of transportation vehicles based on RFID technology of database of the system. The actual application shows that the database has good storage structure, data sharing and consistency.

Research of informatization framework of transportation and sale for large coal enterprise

ZHANG Xiaoyan, CAI Panliang

2014, 40(4): 93-95. doi: 10.13272/j.issn.1671-251x.2014.04.023

<Abstract>(38) <PDF>(2)

Abstract:
In view of problem that coal data is scattered and data sharing is not timely of large coal enterprise, an informatization framework of transportation and sale for large coal enterprise was designed based on detailed analysis of business processes of transportation and sale of coal and combination of the MVC design pattern, open-source framework of Spring3, framework of Structs2, MyBatis, and template engine of Freemarker. The framework achieves network management of transportation and sale of coal, improves accuracy of data management of coal quality in process of transportation and sale of coal, and reaches purpose of timely data updating and sharing between departments of distribution units.

Research of framework and application of coal transportation system

TAN Zhanglu, ZHANG Ma

2014, 40(4): 96-99. doi: 10.13272/j.issn.1671-251x.2014.04.024

<Abstract>(53) <PDF>(4)

Abstract:
The paper took implementation instance of coal transportation system of Fenxi Mining Group as research background, described important role of coal transportation system in coal transportation and dispatching, and introduced overall framework and specific processes of coal transportation system in details, meanwhile analyzed site implementation effect and economic benefits of the coal transportation system in Fenxi Mining Group. The analysis results show that the system standardizes coal transportation processes, greatly improves efficiency of coal transportation, and can effectively control cost of transportation and bring huge economic benefits for the enterprise.

Comprehensive intelligent pre-warning system of coal mine safety

FU Guixiang, ZHOU Hongjun, GUO Jiru

2014, 40(4): 99-101. doi: 10.13272/j.issn.1671-251x.2014.04.025

<Abstract>(51) <PDF>(6)

Abstract:
The paper introduced general framework of comprehensive intelligent pre-warning system of coal mine safety based on Internet of Things, expounded design of each pre-warning model namely gas pre-warning model, fire pre-warning model, flood pre-warning model and roof pre-warning model, and gave business process of intelligent decision. The system can make real-time monitoring and intelligent pre-warning for hidden danger in process of coal mine safety production, so as to improve safety production level of coal enterprises.

Application research of mine spontaneous combustion fire monitoring system with beam tube

XUE Yi, WU Jianming, WANG Junfeng

2014, 40(4): 102-104. doi: 10.13272/j.issn.1671-251x.2014.04.026

<Abstract>(55) <PDF>(5)

Abstract:
The paper analyzed development course and characteristics of mine spontaneous combustion fire monitoring system with beam tube at home and abroad, and indicated mine spontaneous combustion fire monitoring system with beam tube developed by Australia can reflect change trend of main gas in spontaneous combustion areas in time, so as to provide effective pre-warning for mine spontaneous combustion fire. The application result in fully-mechanized face of a coal mine shows that volume fraction of O2 of goaf gradually decreases with advancing of fully-mechanized face, the volume fraction of O2 of deep edge of the goaf is 5%～6% and becomes stable; the volume fraction of O2 of the goaf still keeps above 8%, so it should take corresponding technology measures to prevent phenomenon of spontaneous combustion of residual coal in the goaf within 100～150 m of the fully-mechanized face; the goaf is in asphyxia state beyond 150 m of the fully-mechanized face.

Lightning protection measures of inlet line of a mining area substation and its simulation analysis

TONG Nian, ZHOU Yilong, ZHOU Libing, CHEN Jinlin, GUO Yijia

2014, 40(4): 105-110. doi: 10.13272/j.issn.1671-251x.2014.04.027

<Abstract>(26) <PDF>(2)

Abstract:
The paper introduced some basic situations of lightning protection measures of inlet line of a mining area 110 kV substation, analyzed causes of lightning strike of 35 kV inlet line of the substation, namely line insulation level increased by people is mismatch with on-site insulation level and inlet line tower grounding resistance is too high, and proposed corresponding renovation measures, namely adopting difference protection measures of installation of insulator protection gap with lightning arrester and dendritic grounding device.ATP-EMTP simulation results verify feasibility of the reform measures.

Design and application of multi-functional wireless information transmission platform based on 802.11

LIU Zhigao, DING Qingqing

2014, 40(4): 110-114. doi: 10.13272/j.issn.1671-251x.2014.04.028

<Abstract>(41) <PDF>(2)

Abstract:
In view of problems of single function and low positioning accuracy existed in underground personnel positioning system, an intrinsic safety and multi-functional wireless information transmission platform based on 802.11n was designed. The platform is based on 802.11n transmission protocol and uses signal strength measurement module, which not only can realize high speed transmission of data, voice and video, but also can realize real-time positioning of underground personnel through WiFi signal. The actual test results show that wireless transmission rate of the platform reaches 120 Mbit/s, the signal coverage is 500 m, real-time positioning accuracy is 9.68 m, satisfy requirements of coal mine safety information transmission.

Application research of mine automation system of Kouzidong Coal Mine

ZHENG Jiasong, DING Congshi, GAO Yi, LYU Lei, ZHANG Xiansheng, ZHANG Xianyu

2014, 40(4): 115-117. doi: 10.13272/j.issn.1671-251x.2014.04.029

<Abstract>(25) <PDF>(4)

Abstract:
In view of problems of construction of current mine automation system, the paper proposed a construction scheme of mine automation system of Kouzidong Coal Mine. Each underground subsystem uses Mincos control system as main control unit. The main control unit collects information of internal sensor though bus of Mincos control system and communicates with controller of matching equipment of each subsystem through Modbus and Profibus, meanwhile, the main control unit communicates with surface centralized control system through Ethernet. The actual application shows that the scheme can provide reliable security for production automation of Kouzidong Coal Mine.

Design of I/O driver for ProConOS based on Modbus RTU protocol

FANG Chongqua

2014, 40(4): 118-120. doi: 10.13272/j.issn.1671-251x.2014.04.030

<Abstract>(47) <PDF>(4)

Abstract:
The paper introduced characteristics of Modbus RTU communication protocol, proposed a design scheme of I/O driver for programmable logic control kernel software ProConOS based on Modbus RTU protocol, and conducted on test and analysis. The test and application results show that the scheme can effectively realize interconnection, industrial networking and centralized control of different control equipments which support the Modbus RTU protocol, and provides basis for application of the Modbus RTU protocol in embedded system.

2014 Vol. 40, No. 4

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