Research and Software Implementation of Vibration Component Extraction Method
To solve the problem of not being able to determine the vibration amount of each rotating component from the total vibration amount of the aircraft accessory casing,this paper proposes a vibration component extraction method.Firstly,we integrated the vibration acceleration into the vibration velocity,calculated the fast Fourier transform of the vibration velocity,and obtained a measurement frequency of interest by dividing the collected speed signal by the transmission ratio;Then we extracted two array element numbers of one frequency resolution around the measurement frequency from the frequency array calculated by the fast Fourier transform.Secondly,we indexed the maximum value in the fast Fourier transform amplitude array element between the two array element indices to obtain the vibration component of aircraft accessory gearbox;Then,we corrected the error of vibration component caused by signal windowing by formula.Based on the above method,we developed a software of extracting vibration components to analyze the data of the transmission shaft connected to the hydraulic pump in the aircraft accessory gearbox.The a-nalysis results show that there was a frequency tripling vibration component from a certain time,and the first three components had sudden increases before slowly decreasing.Finally,the developed software was applied in engineering tests,clearly displaying the vibration components in real time,thus achieving parallel storage.This method effectively solves the engineering problem.
Vibration of aircraft accessory gearboxVibration componentFast Fourier transformAmplitude cor-rection