Research On Double Local-fans Control System Based On CAN Bus

Double local-fans are the essential equipment in the production of coalmine, according to national《Safety regulations in coal mine》, in the digging face the ventilation of main fan is required, so does the local fan. Focusing on safety production and actual circumstance of the coal mine, the model of double local-fans control system based on CAN bus is presented in this paper. It is aiming at solving the difficult problem of production accidents caused by gas concentration which exceeds standard in working face, flow entrance, air return gateway, shortage of wind rate and a wrong humanly switching on.In this article, the main line of monitoring network in device leve is designed using CAN bus, and TMS320LF2407A DSP controller is applied to the microcontroller of intelligent node. With monitoring and control software, master controller (namely PC) can realize the control of the local-fan system.Firstly, the hardware of intelligent control node is designed in this dissertation, which includes the whole body design, power circuit, circuit of TMS320LF2407A core system, control circuit, interlock circuit, and intrinsic safety circuit design. Secondly, the software of intelligent node is designed, the fault diagnosis model of expert system based on rough set and neural network is chiefly presented. In this system, the design of whole structure and of each functional module are proposed, fault diagnosis of double local-fans system is accurately realized. Meanwhile, according to the minimized fault diagnosis decision set of local-fan control system which is based on rough set theory, the software of intelligent node is designed. It includes initial program, startup program, fault diagnosis and handling program and CAN communication design etc. thirdly, the reliability of the whole control system is designed, which includes the interference of the CAN bus and intelligent control node. At last, the processs of communication between PC and CAN232B intelligent converting card is discussed. Taking advantage of Microsoft company's Visual C++ 6.0 developing station, PC monitoring and control software is programmed. Through testing the control of the whole local fan system can be realized.All function of the whole system is verified by experiment, and the results manifest that the system runs stably and works in good order and meets the requirements of safety production in coal mine.