Abstract: To eliminate the retarded resonance during starting period in square plansifter, a self-adjustable inertial exciter is proposed. Considering the mechanical characteristic of three-phase asynchronous motor and the friction torque of bearing, the nonlinear dynamic model of the system which consists of the body of sifter, the suspenders and the exciter is established. Since the eccentric distance of exciter is unchangeable and self-adjustable respectively, the four-order Runge-Kutta method is used to simulate the starting process in Matlab. The law of influence of the initial eccentric distance, stiffness and damping of the new exciter on the maximum instantaneous amplitude during starting period is analyzed. The results show that the maximum instantaneous amplitude and the starting time can be greatly shortened during starting period by the novel exciter with appropriate parameters.

Key words: Dynamic modeling, Inertial exciter, Numerical computation, Square plansifter, Starting period