Abstract:Megnetic-liquid double suspension bearing (MLDSB) is a new kind of bearing formed by combining hydrostatic pressure and electromagnetic suspension,which can greatly improve the bearing capacity and stiffness.Due to the coupling of hydrostatic and electromagnetic suspension systems,MLDSB is affected by multiple parameters in the operation process,which makes its operation rule unclear.The sensitivity analysis on the parameters in the system was carried out to find the main influencing parameters.The state space description and the first-order sensitivity equation of the bearing system were derived;and the influences of six characteristic parameters such as oil viscosity coefficient,bearing mass,liquid film thickness,oil sealing edge width,supply flow and supply current,on the vibration of the bearing system were solved through MATLAB simulation.The results show that when each parameter changes the same value,the sensitivity function of bearing rotor displacement to the flow rate λ51,current λ61 and liquid film thickness λ31 in the bearing system are much higher than the influence intensity of other sensitivity functions on the system;the two sensitivity indexes of flow a5,liquid film thickness a3 and current a6 are obviously higher than other parameters;the flow a5 and current a6 are the first and second influencing parameters of the system respectively.The research results provide reference for parameter design and stable operation of MLDSB.