Accurate prediction of dynamic characteristics is an indispensable research foundation for the disturbance mechanism and vibration control of SADS(solar array drive system). The equivalent mechanical parameters of the drive mechanism were deduced with the consideration of drive control, the equivalent dynamics-characteristics analysis model of SADS was built and verified via simulation and experiment, the influence of the drive speed and control gains on the equivalent mechanical parameters of drive mechanism and dynamic characteristics of SADS was discussed. The results show that the equivalent analysis model can accurately predict the dynamic characteristics of SADS with different drive speeds and control gains, and the error between the analysis results and the test data is less than 10%. The equivalent damping of the drive mechanism cannot be affected by the drive speed and control gain, but the equivalent stiffness decreases with the decrease of the control gain and the increase of the drive speed. The drive control gradually becomes an important factor affecting the dynamic characteristics of SADS with the increase of the drive speed.