At the beginning of 21st century, a new method of driving for large telescope was developed, which was based on Arc PMSM (Arc Permanent Magnet Synchronous Motor). This method has many advantages over other traditional drive methods, on the other hand there is a problem of thrust ripple, which will affect the tracking precision of the telescope. In order to solve the problem of thrust ripple, which will affect the tracking precision of the telescope, a control method based on the principle of Space Vector PWM (SVPWM) was introduced. A model of Arc Permanent Magnet Synchronous Motor (PMSM) was built up under the condition of Matlab/Simulink. And SVPWM method was adopted to construct Arc PMSM control model which contained velocity and current control loops. Simulation results show that the motor with the load can get a fast dynamic response and ideal three-phase sine wave current. The speed andthrust are smooth, and the thrust ripple is smaller than 5%, so this control method can meet the needs of the trackingrequirement of the large telescope.