Research On Data Acquisition System Of Essential Safety Monitoring In Coal Mine

For a long time,coal industry has been an important material basis for the social and national economic development of our country.Due to continuous mining for many years,shallow coal has been exhausted and can only be mined underground,and underground mining is accompanied by methane gas,CO gas and Dangerous sources such as dust seriously threaten the safety of coal mine property and the safety of people's lives.Therefore,it is particularly important to establish an advanced and reliable safety monitoring system.At present,the main problems of China's coal mine safety monitoring data acquisition system are: most sensors use catalytic and electrochemical technology,which has short life,poor stability,single sensor communication interface and poor system scalability;the alarm mechanism of the acquisition system is not perfect,and there is a lack of grading alarms;Underground environmental monitoring has a wide range,long-distance communication between acquisition system and substation requires laying a large number of cables,which is not only difficult to install and maintain,but also vulnerable to the interference of complex underground environment,resulting in the reduction of data transmission accuracy.There are many monitoring points in the mine environment.The analysis and processing of a large number of data in the acquisition system is easy to form redundant data.At the same time,the time of the power consumption of the system and data processing are increased,which leads to the failure of the monitoring center on the well to obtain reliable data in time.On above problems,combined with the intrinsic safety thought,the paper puts forward the idea of constructing the intrinsic safety monitoring data acquisition system of coal mine,and proposes solutions to the existing main problems.The main research contents of the thesis are as follows:(1)Design a new type of data acquisition terminal to improve the security and reliability of the system.The system acquisition terminal is designed with a variety of standardized communication interfaces to facilitate the integration of multiple systems.A variety of sensor interfaces are designed to improve system compatibility;the terminal alarm mechanism is improved,and two levels of sound and light alarms are adopted,which are slightly dangerous and serious;the collection terminal designs intrinsically safe circuits according to the requirements of GB 3836 series standards,and improves system explosion-proof and electromagnetic interference resistance.Through the hardware and software design of the system acquisition terminal,the function of the collection terminal is completed in the laboratory environment.The test results show that the terminal meets the functional requirements of data acquisition,transmission,display and storage.Through the hardware and software design of the system acquisition terminal,the functional test of the collection terminal is completed in the laboratory environment.The test results show that the terminal meets the functional requirements of data acquisition,transmission,display and storage.(2)A combination of wired and wireless communication technologies is chosen by the system to support multi-network convergence.Through comparative analysis,the main network communication between the acquisition system and the sub-station is based on CAN bus,and the interface circuit of CAN bus is designed.For the narrow area such as underground working face,which is hard to wiring,ZigBee wireless communication technology is used for data transmission in the system acquisition terminal.ZigBee networking design includes terminal nodes,routing nodes and hardware and software design of gateway modules.The ZigBee wireless communication distance test is completed in a laboratory environment,and the test results show that the system communication distance requirement is met.(3)The compressed sensing algorithm to data fusion of the monitoring system is used in the thesis.Through comparative analysis,the thesis selects the SAMP algorithm which is better in reconstruction and more suitable for solving the problem of unknown signal sparsity.The SAMP algorithm is improved by Dice coefficient matching criterion and exponential variable step size.The improved algorithm is analyzed under different sparsity K and different observations M by MATLAB experimental simulation.The results show that the improved SAMP algorithm improves the reconstituted power and shortens the average reconstruction time.