Study On Key Technologies Of Coal-mine Power Monitoring System Based On CAN Bus

With the increasingly high improvement of mechanization in the undergroundcoal-mine, electricity as a source of power also requires its power network to achievecomprehensive automation. But the current power of underground coal-mines in ourcountry are still manually controlled, and poor geological environment makes shortcircuit, overload, leakage and other power faults easy occurred, this will not only needto waste a large amount of manpower and resources, but also if not detected in timeand selectively cut off the power fault slip, the explosions such as gas and smut mayoccur when in the maintenance. Therefore, on the basis of the existing intelligentprotection device, this article put forward intelligent coal-mine power monitoringsystem based on S7-300PLC and CAN bus, give full play to the advantages of PLCand field bus.Firstly, analyze the functional requirements of coal-mine power system, thusbuild a three-tier network model of underground coal-mine power monitoring system,and describe how it works in detail. Then the paper focuses on four key technologiesfor the realization of the monitoring function，including "modular technology","communications technology","safety technology " and "smart technology".(1) Discuss the modular structures of monitoring system. According to thespecial underground conditions, complete a monitoring program study of eachparameter for underground power process, including the design of intelligent powercollection device. Propose a concrete modular research programs to meet themonitoring system requirements, in order to achieve coal-mine monitoring andfollow-construction.(2) Completed the design of CAN interface circuit andCAN-RS485converter, and study the communication between CAN nodes in detail,in order to achieve communication between intelligent power collection device andthe PLC. According to the underground and ground communication requirements,proposed the Ethernet communications solutions between PLC and monitoring host (InTouch).(3) Through theoretical analysis of power fault protection, give a specificmethod to achieve underground power fault protection. Use the InTouch software onthe host to design friendly interactive programs, thus realize the real-time monitoringof system running status.(4) Further research the BP neural network, and threeimprovements in its algorithm are completed to accelerate convergence. use theimproved BP neural network to create a fault warning model, which optimize thepower monitoring system, so that when detect some relevance between the real-timecollected data and historical fault data, the monitoring system will be able to alarmbefore the specific fault occur, and to ensure coal-mine power safety.The underground power monitoring system designed in this paper will realizefour-remoteness function for the coal-mine, include remote-control, remote-adjust,remote-information and remote-measurement. It will effectively shorten the faultprocessing time and the range of losing electrical power, reduce manual errors andeconomic losses, ultimate realize the coal-mine power intelligent. It is a strongtechnical sense to improve the management level of coal production and distributionautomation of coal mine.