Dynamic analysis and identification of unbalance and misalignment in a rigid rotor with two offset discs levitated by active magnetic bearings:a novel trial misalignment approach

作     者：Prabhat Kumar Rajiv Tiwari 

作者机构：Department of Mechanical EngineeringIndian Institute of Technology GuwahatiGuwahatiAssam781039India 

出 版 物：《Propulsion and Power Research》 (推进与动力（英文）)

年 卷 期：2021年第10卷第1期

页      面：58-82页

核心收录：

学科分类：07[理学] 0701[理学-数学] 070101[理学-基础数学] 

主　　题：Misalignment Unbalance Active magnetic bearing Gyroscopic moment Fast Fourier transform Identification 

摘      要：Rotating machinery is an essential and crucial component of numerous mechanical systems in modern industries,transport vehicles,and in several other *** vibrations on rotating equipment due to multiple faults may cause catastrophic failure in machines and lead to hazardous ***,there is a need for perceiving the dynamic nature and identifying the faults for the safe,smooth and effective operation of *** paper proposes a novel trial misalignment approach to estimate the misalignment with a similar concept as the trial unbalance in the rotor *** magnetic bearing(AMB)misalignment with the rotor has been investigated with residual misalignment and additional trial misalignment *** trial misalignments are provided in addition to the unknown misalignments of the residual misalignment *** the execution of this methodology,the dynamic model of a four-degree-of-freedom unbalanced and misaligned rigid rotor with two offset discs supported by two active magnetic bearings has been mathematically *** offset discs result in the gyroscopic effect at high rotor *** of motion of the rotor-AMB system have been derived and solved to generate the time domain rotor displacement and controlling current responses at AMB positions.A fast Fourier transform technique has been utilized to convert the time domain responses into the frequency domain for estimation of unbalance eccentricities and phases together with force-displacement and forcecurrent stiffnesses of misaligned AMBs as well as AMB s constant forces using the developed identification *** values of AMB s parameters for both residual and additional trial misalignment cases are evaluated to estimate the four unknown *** of the algorithm has also been carried out at multiple spin speeds against measurement signal noise in rotor responses and bias errors in rotor system parameters to check its effectiveness