动态气隙偏心下同步调相机转子振动研究OA北大核心

Aiming at the problem that the unbalanced magnetic pulling force induced by the dynamic air gap eccentrici-ty can cause severe vibration of the synchronous condenser rotor,the unbalanced magnetic pulling force is theoretically cal-culated and simulated.It is found that the unbalanced magnetic pulling force is dominated by the basic frequency of rotating around the rotating axis,and the magnitude of the force is positively correlated with the eccentricity.Through the modal anal-ysis,it is found that the rotor critical speed increases with the increase of bearing stiffness,and the change is obvious in the interval of bearing stiffness of 1×106-1×1010 N/m,in which the rotor critical speed can be changed by changing the bearing stiffness.The vibration mode diagram shows that when the bearing stiffness is below 1×106 N/m,the rotor shows a rigid mode.When the bearing stiffness is above 1×1010 N/m,the rotor shows a bending mode.When the bearing stiffness is in the range of 1×106-1×1010 N/m,the rotor shows a mixed mode which changes from rigid mode dominant to bending mode dom-inant.In the harmonic response analysis,the unbalanced magnetic pulling force is loaded onto the rotor surface.It is found that the rotor of the synchronous condenser has obvious amplitude peaks near the intrinsic frequency,and the amplitude peaks decrease with the increase of the bearing stiffness.The larger the eccentricity is,the larger the influence of the change of the bearing stiffness on the amplitude peaks is.And the amplitude peaks increase with the increase of the eccentricity.Re-sults show that the synchronous condenser rotor vibration can be suppressed by changing the bearing stiffness and reducing the rotor eccentricity.