Critical speed prediction and model correction of a dual-planetary gear speed increaser
HUANG Hongtao
SHI Yibo
CHEN Junhao
TUO Yunsheng
HUANG Shuaizong
HOU Nai
SHI Lubing
QU Yanghua
Abstract：[Objective]In order to accurately predict the dynamic characteristics of an ultra-high-speed dual-planetary gear speed increaser used in rotor strength tests and to avoid resonance risks,this study conducts an in-depth investigation through a combination of simulation and testing.[Methods]Firstly,a rigid-flexible coupled dynamic model of the transmission system including a flexible housing was constructed.The natural frequencies and vibration modes were obtained through modal analysis and Campbell diagram analysis,and the critical speeds were predicted.Secondly,a vibration test bench was built,and the actual critical speeds of the system were identified through a run-down test.Finally,addressing the discrepancies between initial simulation and test results,the sensitivity of the first three orders of critical speeds to various bearing support stiffnesses was systematically analyzed.On this basis,a parameter inversion optimization method was employed to correct the bearing stiffnesses in the model.[Results]The results indicate that the bearing stiffnesses of the input shaft and planetary shaft predominantly govern the first and third-order critical speeds,respectively,while all three bearing stiffnesses collectively influence the second-order critical speed.The error between the corrected predicted critical speeds and the test values is less than 5%.This research provides a reliable method and model basis for the dynamic design,condition prediction,and fault diagnosis of this type of high-speed planetary speed increaser.
Keywords：Dual-planetary gear speed increaserCritical speedRigid-flexible coupling modelSupport stiffnessParameter inversionModel correction
Publication Date：2026-04-30
Online Publishing Date：2026-09-12(First online date of this platform, not the publication date of the document)
Pages：10( 112-121 )