Design And Research Of Self-powered Wireless Sensor Network System For Shearer Equipment Diagnosis

As a vital tool of comprehensive mechanized coal mining in the current coal industry, shearer equipment performs as a key factor in safe and highly efficient operation on the coal face depending on its efficiency, stability and security. At the present stage, the diagnosis equipments deployed on shearers are mostly using a wired mode, of which complicated cabling may causes an operation inconvenience at a certain extent. Battery life, as a restrictive factor existed in all the wireless sensor networks must be confronted once using the WSN technology instead of wired devices.In view of the fact that the shearer monitoring equipments had many limitations, a self-powered WSN integrated system is proposed, which carries out the power supply by the process that vibrating piezoelectric energy harvesters with the cantilever beam structure collect mechanical energy from the oscillatory shearer and monitors vibration state of shearer real time and on line based the WSN weaved by utilizing ZigBee technology.During the procedure of system research and built, author lucubrates the basics of the vibrating piezoelectric energy harvesters with cantilever beam structure; and the operating principles and design approaches of a energy manager are studied; then the software framework protocol named Z-stack consistently practiced in ZigBee is deeply explored, include a carrier sense multiple access with collision avoidance mechanism in MAC layer, network formation, notes adding and routing in network layer as well as application layer criterion like application framework and object; on account of these preliminary theoretical researches, author designs the hardware composed by micro energy management, data acquisition and processing, ZigBee wireless RF etc; software based on the Z-stack is respectively project on terminal nodes, coordinators and routers. By executing a series of simulation tests on the node prototypes included electrical performance of piezoelectric energy harvesters, power endurance of micro energy manager, communication reliability and real-time performance with a large-sized vibrostand, it shows a good performance on energy endurance, signal sensing, wireless data receiving and dispatching. By virtue of simulating working condition of the shearer, a self- powered WSN system working on the coal cutter is initially realized, which helps the shearer monitor improving toward the distant and portable services.