Research on singular point characteristics and parameter bifurcation of single DOF nonlinear autonomous bearing system of magnetic-liquid double suspension bearing

Magnetic-liquid double suspension bearing is composed of electromagnetic supporting system and a hydrostatic supporting system. Because of electromagnetic supporting system and a hydrostatic supporting system are nonlinear inter-coupling complicated system, the degree of nonlinearity is strengthened. Firstly, the structural features and regulating mechanism are expounded, and the nonlinear dynamic equations of the single-DOF autonomous supporting system are established. Secondly, singular point characteristics of the single DOF autonomous supporting system are analysed with corresponding criteria of Lyapunov stability and the change law of phase trajectories is revealed, and then the shape the change rule of basin of attraction are obtained. Finally, take magnetic-liquid proportional coefficient K as variation parameter, the root cause and physical significance of the static parameter bifurcation of the single-DOF autonomous supporting system are revealed, and then the effective measures to avoid parameter bifurcation are presented. The research can provide the theoretical reference for the design and nonlinear analysis of MLDSB.