Investigation On The Torsional Vibration Measurement Of Rotating Shafts Based On Zebra Strip

In a rotary power machine,the rotor shafting is its core component.Torsional vibrations increase the fatigue damage of the shaft and reduce the service life.In severe cases,the unit shafting will be damaged or broken,which will affect the reliability operation of the unit.Therefore,in the vibration analysis of rotating machinery,the accurate measurement of the torsional vibration of the rotating parts is very important,choosing a reasonable torsional vibration measurement method,and analyzing and discharging the error generated during the measurement process is crucial.This thesis mainly adopts the zebra belt with simple application and the torsion signal acquisition.It measures and corrects the error generated during the signal acquisition process by using the zebra belt.Combined with the zebra belt correction method,the calculation principle of the instantaneous speed of the torsional vibration signal is adopted.Improvements were made and simulations were performed using simulated signals.Combined with the torsional vibration measurement technology based on zebra strip correction,the virtual instrument technology can quickly construct a professional instrument which meets the torsional vibration measurement technology.Considering the convenience of virtual instrument based on software design,it can collect and analyze at the same time.It can efficiently and accurately collect and analyze the speed signal.It can also modify and upgrade the instrument and meet the analysis on multiple computers by installing it.The full text of the work is as follows:(1)The basic theory of torsional vibration measurement,the torsional vibration measurement technique and the torsional vibration measurement error correction method are studied in detail.A brief overview of the torsional vibration measurement principle of the rotor shaft torsional vibration system is carried out,and the hardware performance involved in the torsional vibration measurement system of the rotor system is studied.(2)Calculate the instantaneous angular velocity required to extract the torsional vibration signal by using the zebra band,and discuss the error caused by the inhomogeneity of zebra band to the torsional vibration measurement and realize the instantaneous angular velocity method based on zebra band correction.Finally,through the simulation experiment,the torsional vibration signal simulation model,the sweep pulse signal simulation principle and the cursor edge detection technology are established.The simulated uneven zebra strip is corrected according to the algorithm,and the waterfall graph and trend are analyzed according to the order analysis.The drawing of the graph proves that the feasibility of the torsional vibration analysis algorithm.(3)Based on the principle of virtual instrument design,the system design of the virtual instrument for torsional vibration measurement and analysis of the system is carried out.This chapter mainly plans the system's algorithm function flow chart from the design purpose and requirement analysis of the system and clarifies the realization goal of the system.Then,according to the system requirements analysis,the virtual instrument is overall designed according to the description of the function chart.Design and introduce the modules of the virtual instrument as required.(4)On the CUT-2 rotor test bench,the torsional vibration measurement test of the double-disc rotor was designed.According to the comparison of the output signals of the laser sensors corresponding to the zebra belt,the torsional vibration was determined according to the presence or absence of torsional vibration.The results show that the torsional vibration measurement method is effective.