Identification Of Rotor Unbalance Based On Robust Analysis Of High Break Point

In modern production,rotor imbalance is one of the important problems in rotating machinery failure.Unbalance will affect the safe operation of machinery,and even cause heavy casualties and economic losses.Therefore,the identification of unbalanced quantity is particularly important.Therefore,this paper proposes a robust regression analysis based on high collapse points to identify rotor imbalance.Based on the research of the rotor test rig,the influence of the rotor disc is neglected,and the modal frequency of the rotor test rig is solved.The influence of the rotor inertia on the natural frequency is analyzed and solved.The rotor test rig is analyzed as The balance method and fault characteristics of rigid rotor and flexible rotor;mathematical modeling of rotor imbalance identification using least squares influence coefficient method and linear vibration theory,and the linear regression model of multi-disk rotor test bench is obtained;considering robust regression method ——M estimation and GM method,and using GM to estimate the high collapse point characteristics,a method based on HBGM estimation with high breakdown point is proposed.The method is based on M estimation and GM estimation.In the case of the known influence coefficient matrix,after measuring the unbalanced vibration data of the rotor test rig,the unbalance amount is identified.HBGM estimation can not only identify the outliers of the influence matrix of the rotor test bench,but also identify the outliers in the vibration data,and it has higher robustness.Before the dynamic test of the rotor test rig,it is necessary to grasp the characteristics of the rotor fault and its modality.Among the fault characteristics of the rotor test bench imbalance,the most obvious is the axis trajectory.The rotor axis trajectory and modal analysis are simulated.The mesh is divided by Hypermesh.The flexible rotor is combined with Adams to simulate the unbalanced axial trajectory of the rotor test rig.The elliptical trajectory generated by the imbalance of the rotor test rig can be obtained.The modal analysis of the test rig was performed by Ansys workbench and Simsolid to obtain the Campbell diagram,modal frequency and mode shape of the rotor test rig.The forward direction of the rotor can be seen from the Campbell diagram,so that the influence of the disc on the first-order and second-order natural frequencies of the rotor test rig can be obtained.When Ansys workbench is used for simulation,the modeling process of the rotor test bench is complicated,such as meshing and bearing establishment,and Simsolid meshless technology is used for modal analysis.This method does not require meshing.Automatic identification of contact connections,etc.,only need to set up a simple contact,this method can also get a more reliable modal frequency and vibration mode,which is more simple and convenient for designers.Finally,based on the rotor test bench for experimental verification,the critical speed and axial trajectory of the rotor test rig are measured.The critical speed of the rotor test rig is basically consistent with the calculation results and simulation results.The axial trajectory of the unbalance is basically consistent with the Adams simulation results..Finally,the HBGM method for rotor imbalance identification is experimentally verified.The HBGM high crash point robust estimation method is used to identify the unbalanced amount and the outliers in all data.The experimental results show that the method can identify the outliers in the influence coefficient matrix and the outliers in the vibration response of the rotor unbalance,and obtain a relatively accurate estimation of the rotor imbalance and phase.It has certain practical applications.