Dynamic Simulation of Maglev Water Pump on A Moving Base by Using Multibody Dynamics Method

As one of the key components of a rotating machinery, the bearing has a significant effect on the dynamic response of the system. Compared with traditional mechanical bearings, the magnetic bearing has many advantages such as no contact and friction, no need of lubrication, no wear, low noise, high rotational speed, etc. Therefore, the magnetic bearing is an ideal support for rotating machinery, i.e. a maglev water pump. During the modeling and simulation the magnetic bearing, it is usually simplified as a spring-dampers with equivalent stiffness and damping, which ignore the dynamic characteristics of the magnetic bearing. Besides, the study of simulation mainly focuses on the vibration reduction of the rotor or the vibration transfer to the base, while little was known about the dynamic response of the maglev machinery system on a moving base. In this paper, a time-domain rigid-flexible coupling simulation model of a maglev water pump on a moving base is established by using multibody dynamics method. In this model, the flexible rotor is simplified as several discrete rigid parts connected with massless beam force and the control system of the magnetic bearing with PID controller is realized by utilizing state space equations. Then the dynamic response of the maglev water pump on a pitching and rolling base was obtained based on the established model.