An Accurate Extraction Technology Of Unbalance Vibration For Rotor Under Rotating Frequency Interference

Due to manufacturing,installation errors and discontinuity of materials,the centroid of the rotor will more or less deviate from its geometric center,that is,there is unbalance.When the rotor rotates at high speed,the unbalance will lead to undesired vibration.It is of great significance for the field of rotating machinery equipment to accurately extract the unbalanced vibration signal by digital signal analysis and processing method,monitor and adjust its running state by analyzing the possible fault factors of rotating equipment.Therefore,in this paper,an accurate extraction technology of unbalance vibration for rotor under rotating frequency interference is studied.The main research content is as follows:Firstly,the double-face effect coefficient method and three methods of amplitude and phase extraction of unbalanced vibration signals are analyzed.Then,the dynamic model of rotor with bending and unbalanced faults is established,and its solution and simulation analysis are carried out.Discussing some typical faults of rotor vibration system and their changing characteristics with rotating speed,and then the theoretical basis of unbalanced vibration signal purification is obtained.Secondly,the reduction and purification specific steps of unbalanced vibration signal are proposed,and the resampling technique of the sensor signal is derived in detail.On the basis of the above,combining the signal resampling technique with the rotor vibration characteristics,a reduction and purification technique is presented,which eliminates the influence of non-unbalanced factors and realizes the accurate extraction of unbalanced vibration signal under rotating frequency interference.Based on signal reduction and purification technique,an improved dynamic balancing method is proposed.Thirdly,the theoretical error of FFT vibration signal extraction method is described and the measures to improve the precision of vibration signal extraction.In addition,the parameter errors in the dynamic balancing process are discussed,and the balance error is analyzed through qualitative and quantitative,which provides theoretical support for reducing dynamic balance error in engineering practice.Finally,the dynamic balance experiment is carried out on the rotor experimental platform.Based on the platform,the variation law of the original vibration response,the vibration response after traditional balancing method and the vibration response after reduction and purification balancing method with rotational speed are analyzed,and the final experimental results show that the dynamic balancing method based on signal reduction and purification can restrain the unbalanced vibration response of rotor at high speed.The research results in this paper are helpful to ensure the high-speed rotor safe and stable operation.