Research And Design Of System For Avoiding Over Tripping Based On CAN Multi-machine Communication

Coal mine safety production has been attached great importance to the issue of theState Administration of Work Safety and coal mining enterprises There is needed to notethat the reliable and continuous working of coal mine power supply network is animportant guarantee for coal mine safety production. But because of a variety ofobjective conditions and technical constraints, vertical selective protection system is notavailable when short circuit breakdown occurs, which results in over tripping in coalmine power supply network of our country. Serious conscious must be taken it for overtripping creates severe power outage underground coal mine so that the normalproduction is interrupted. What is worse, it brings great deaths and damages to theworkers underground coal mine.To avoid over tripping effectively, this thesis presents the research and design of anew system for avoiding over tripping on the basis of comparison of prevenientsolutions after reading an amount of related literature. The overall compositions andbasis principle are introduced in the paper, focusing on a solution of anti-over trippingbased on CAN (Controller Area Network) multi-machine communication. In thissolution, protect devices are used at every level of coal mine power network linked toCAN BUS, among which one is able to communicate with another by switching CANmessage. In the following, this paper provides the design of hardware circuit andprogramming about the protect device. In this regard, hardware circuit deals with MCUperipheral circuit, data acquisition circuit, CAN communication and CAN node DIPswitch circuit exhaustively. Additionally, the design of necessary programming aboutthe protect device including main programming, initialization programming and CANcommunication programming are also described. It is shown that the new system andsolution for avoiding over tripping based on CAN multi-machine communication canprevent over tripping from taking place in coal mine power supply network effectivelyand it has a significant practical value.