Active vibration suppression of a magnetic–ball bearing hybrid supported rotor system

The vibration problem caused by milling is a key factor restricting high-precision and high-efficiency machining. Traditional passive vibration suppression methods are limited by fixed structural parameters and lack sufficient adaptability to dynamic operating conditions, making it difficult to achieve effective broadband vibration control. Magnetic bearings, with their non-contact characteristics and active controllability, provide a new idea for milling vibration suppression. To overcome these limitations, this paper proposes a novel hybrid magnetic-ball-supported flexible rotor system that combines active magnetic bearings with mechanical ball bearings, thereby achieving both controllable dynamic stiffness and stable rigid support. Based on the milling force model and the hybrid support rotor dynamics model, a coupled mathematical model is established, and the vibration suppression effect of the magnetic bearing on milling induced vibration is investigated by magnetic force regulation under PID control. Furthermore, milling force signals were generated using a simulation platform and applied to the rotor test bench to conduct numerical simulations and experimental validation. The results demonstrate that the proposed hybrid support strategy can significantly reduce milling-induced vibration amplitude, improve rotor dynamic stability, and enhance vibration suppression performance over a wide operating range. This study proposes a new hybrid vibration control scheme for high-speed, high-precision milling systems and provides a method for intelligent vibration reduction in advanced machining equipment.