Design Of Distributed Real-Time Vibration Monitoring System

Rotating machinery is the critical equipment for the electric power, petroleum and chemical, metallurgy, mechanism, aviation and military department. Monitoring for rotating machinery state is an effective strategy that can insure safe and highly effective running of large equipment as well as avoid malignant accident. The traditional on-line vibration monitoring is mostly single monitoring mode, i.e. one machine is controlled by one monitoring system. Its disadvantage is low efficiency, the wasting of many manpower and material resources and the extrusive limitations of this model with the enlargement of the scale of the factory as well as the increased number of machines.The article designs a distributed vibration monitoring system which realized the centralizing of monitoring, management, diagnosis through link distributed lower computers by Bus and successfully resolved many problems, just as substantive and widely distributed measuring points, the difficulty of monitoring, operation, management and diagnosis. It has high security, flexibility in expansion, great network ability, low cost and strong functions.The system is composed of the data acquisition and processing module, network communication module of CAN Bus and monitoring module of the upper computer. The data acquisition and processing module used the DSP2407 as core processor, which had high processing speed and powerful peripheral functions that can satisfied with the acquisition and processing of vibration signal. By using of CAN Bus as communication with upper computer, it has outstanding reliability, celerity as well as flexibility and can effectively support distributed system. The connection between the upper computer and the lower computer can synchronously operate two independent CAN network and CAN interface card and can compatible with LabVIEW. The graphical programmable language LabVIEW adopted by the upper computer can make the monitoring man-machine interface more intuitionistic.Through the time domain and frequency domain analysis, including real-time vibration wave, wave after filtering, spectrum, amplitude and frequency curve, shaft centerline orbit, the system can timely monitor the operation state of the rotating machinery and forecast equipment failure. By using of LabVIEW SQL Toolkit and Report Generation Toolkit, the data-base interlinkage and auto-creating of report forms were realized.Investigation and study are made in the following sections:(1) DSP-Based Data Acquisition and Processing moduleBy using of TI's TMS320LF2407 as core processor of lower computer, the vibration signal acquisition and digital signal processing were achieved, including digital filtering and fast Fourier transfer, as well as the communication between CAN interface and the upper computer.(2) Based on CAN Bus network communication moduleUsing of fieldbus technology of the CAN Bus constructs distributed network and communicates with upper computer, including internal communication interface program and external CAN communication interface program, compiling receiving and sending program of CAN communication, building network database by SQL Server in order to storage acquisition data.(3) Based on LabVIEW monitoring software design to upper computerUsing of LabVIEW development platform process and display analysis results of vibrationsignals, including power spectrum, amplitude spectrum, shaft centerline orbit and displayingdatabase data and auto-creating report forms.