Design On Signal Analysis And Treatment Unit Of The Turbine's On-Line Monitoring System

The tendency that the turbine becomes macro-scale operations technology with each passing day enlarges the harmfulness of accidents, so the vibration monitoring and the fault diagnosis technology of the turbine are more highly required. The effective monitoring and diagnose are based on the deeply analysis and grasp of the vibration characteristic of the turbine, in the paper, the signal analysis and treatment unit of the turbine's monitoring system on line is designed to achieve the display of the vibration characteristic of the turbine effectively, which is based on embedded technology, TFT-LCD and periodogram,so that,the staff can accurately judge the characteristic of the turbine's faults to make the inspection and repairs easily.Firstly, the design plan of the hardware and software for the whole system, together with the technological choices, are analyzed in the paper, the embedded systems is designed basing on ARM,μC/OS-Ⅱreal-time operating system and TFT-LCD in terms of hardware, which can carry on the estimation of the real-time periodic map and the entire design plan of the waveform display for the collected vibration signals, carries out schematic diagram scaling and the procedure for PCB centering on the LPC2138. The software whose center is periodogram, is finished by the c programming language in the ADS 1.2. The design is characterized by the modularization, openness, the fine interface between human and computer, advanced function, high quality spectrum analysis and so on. Secondly, on the base of analyzing the defect of the periodogram, the vibration signal is simulated by the way of Welch, multi-taper method and wavelet analysis independently, at the aim of improving frequency resolution and variance of the vibration signal's spectrum analysis, at the same time, being easy to upgrade the system. Finally, the system is debugged in VT100, after being debugged, the system could meet the design requirements well and work smoothly and steadily, could monitor the instruments of the rotary machine in the power systems successfully.From the system design process it can be seen that the frequency resolution and variance of the power spectrum estimation can directly influence the failure monitoring's accuracy of the local unit assembly. Spectrum estimation is the key to the vibration detection and the technology of failure monitoring, therefore, research and improvement of the spectrum analysis have very significant and practical meanings in this field.