高速飞轮与电机耦合动力学模型研究

STUDY ON COUPLED DYNAMIC MODEL OF HIGHSPEED FLYWHEEL AND MOTOR

基于替代映射方法分别建立主动磁轴承和永磁同步电机的非线性模型,并与飞轮转子动力学模块、PID控制器等组件结合,构造高速飞轮转子与电机耦合的非线性动力学系统模型。仿真结果表明,替代映射方法计算得到的永磁同步电机齿槽转矩数值与有限元模型结果之间误差较小,具有良好的精度,可正确描述其基频到多次倍频的振动特性。永磁同步电机转子偏心作用力随着转子振幅的增大而增强,会显著削弱主动磁轴承对飞轮转子的控制能力。基于前人“双弹簧”模型,结合永磁同步电机替代映射模型,建立包含主动磁轴承和永磁同步电机的“三弹簧”模型。仿真计算结果表明,永磁同步电机转子偏心作用力改变了飞轮转子的第二临界转速的频率和振幅,作用力较大和位置偏置会造成第二临界转速附近的运动失稳。

Nonlinear models of the active magnetic bearing and permanent magnet synchronous motor are built respectively based on the alternative mapping method,and combined with flywheel rotor dynamics module,PID controller and other components to construct a coupled nonlinear dynamic system model of the high-speed flywheel rotor.The simulation results show that the calculation error of the permanent magnet synchronous motor cogging torque between the alternative mapping model and the finite element model result is tiny.This indicates that the alternative mapping method has good accuracy,and can correctly describe the cogging torque vibration characteristics from the fundamental frequency to multiple frequencies.The eccentric force of the permanent magnet synchronous motor rotor increases as the rotor vibration amplitude increases,and it may significantly weaken the control capability of the active magnetic bearing to the flywheel rotor.Based on the double-spring model in previous studies,a three-spring model is built by combining it with the permanent magnet synchronous motor alternative mapping model.The simulation results show that the eccentric force of the permanent magnet synchronous motor rotor changes the frequency and amplitude of the second critical speed of the flywheel rotor,and a larger eccentric force and position offsets may cause motion instability around the second critical speed.