Abstract: The self-synchronous process of a vibration system driven by two exciters rotating oppositely was investigated by simulation and experiment. The rotational velocities of the two motors and phase differences between the two exciters were chosen as indexes to represent for the self-synchronous process. By comparing the changes of the phase difference， the most important influence factor of the phase difference is motor， and the second is exciter， while the last one is the vibration rigid. The simulation and experimental results show that the initial phase difference between the two exciters and the initial velocities of the two motors have no effect on the self-synchronization. When the synchronous condition is satisfied， the two motors can achieve synchronous motion with different power supply frequencies. When change the masses of the two exciters， the phase of the bigger mass lags behind the smaller one. When the distances between the rotary centers of the two exciters and the mass center of the vibration rigid body are different， the phase of the bigger distance lags behind the smaller one. The phase difference can be reduced by adjusting the power supply frequency， which are caused by motor parameters， the mass of exciters， and the motor installation position and so on.

Key words: vibration system, self-synchronous process, phase difference, synchronization, exciter