抄録
Active magnetic bearing (AMB) becomes to be widely used in various kinds of rotating machinery. However, as the magnetic force is nonlinear, nonlinear phenomena may occur when the rotational speed becomes higher and the delay of control force relatively increases. In this paper, the magnetic force is modeled by considering both the second order delay of the electric current and the first order delay of the magnetic flux. The AMB force is represented by a power series function of the electric current and shaft displacement. The nonlinear theoretical analysis of the vertical rigid rotor supported by the AMB with the PID control theory is demonstrated. The effects of the gain of the integral feedback on the nonlinear phenomena are clarified theoretically and experimentally.
