The Research Of Automatic Positioning Dust Suppression Control System By Spray In Fully Mechanized Coal Face

With the high mechanization degree, the big dust production and serious dust harm, fully mechanized coal face is considered as the focus of dust prevention and control work in the coal mine. High pressure spray dusting is one of the most effective and direct methods for dust removal in underground coal mine, but at present most of the high pressure spray dusting system has a low degree of automation, spray range is small, the intensity of labor is big and the dust effect is not ideal. Therefore, in this paper, on the basis of looking into the characteristics of fully mechanized coal face and dust distribution in fully mechanized coal face, research on the automatic positioning dust suppression control system by spray in fully mechanized coal face is conducted in order to solve the problem of high dust concentration in fully mechanized coal face and reduce the labor intensity of workers and the probability of suffering from pneumoconiosis.According to the characteristics of fully mechanized coal face, this paper analyzes major sources of dust production and dust distribution, and determines the main functions and the master-slave type frame structure for the automatic positioning dust suppression control system by spray in fully mechanized coal face, which masters station and slave station communication through RS-485 bus. At the same time, this paper also determines the scheme which infrared communication is used to detect the shearer position, wireless touch sensors to detect the position of moving hydraulic support and releasing coal, dust concentration sensor to collect the signal which is beyond dust concentration standards, and controlling the electric ball valve open or close to spray dust fall.By making a research on the infrared emission receiving system and the technology of infrared signal encoding and decoding and then using the circuit of infrared transmitter and infrared receiver designed by a pair of special infrared coding and decoding chip, the infrared communication and the function of detecting the shearer position are realized.After the comparison on characteristics among several kinds of short distance wireless communication technology, the wireless communication module is selected. According to the pressure changes when hydraulic support moves and releases coal, the structure and function of wireless touch sensors are determined. Researches on the power saving mode and communication protocol for wireless touch sensors are done and the designs of modular hardware with low power consumption and anti-jamming software for wireless touch sensors are completed.This paper analyzes the major functions of the spray controller, and designs the spray controller hardware structure. By using single chip microcomputer as the centre control module, the design of modular hardware circuit for the spray controller is achieved, and the dust concentration sensor is selected according to the signal acquisition method.According to the major functions of the spray controller, the modular software design for the spray controller by using C language programming is completed. This paper has a study on the MODBUS communication protocol, and designs the communication protocol for the master station and slave station system. The function design for the spray position monitor by using the MCGS configuration software is completed, mainly including the design of human-computer interface and operation strategy script.The infrared transmitter, the infrared receiver, the wireless touch sensors and the spray controller are made, and the software and hardware debugging and the experiments on the control system are completed in the laboratory. This paper tests the infrared receiving effective distance and angle, the wireless touch sensors communication and power consumption, the spray controller and the spray position monitor communication and analyzes the influence factors according to the results. After completing all parts of the system assembly, the overall system operation experiment is done in the workshop with the coal mining process simulated, whether the system running normally or not is tested, and the problem of the system real-time performance is analyzed. At last, the system is applied to the coal mine, and the spray suppression dust experiment is done in the coal mine after the system runs normally. The dust concentration in the full mechanized coal face before and after the system running is collected, and the results show that the control system can run normally and the effect of dust suppression is remarkable.