Abstract: Due to the existence of a large number of nonlinear devices in the accelerator system, a large number of ripples are generated, which seriously affects the control of the accelerator magnetic field on the particle trajectory. In order to realize the suppression of accelerator DC power supply ripple, related researches mainly focused on using voltage-type active power filter to reduce DC power supply ripple, but this method has problems such as insufficient suppression accuracy, response delay, and large switchgear loss. In view of the above problems, this paper compares the main circuit topology of current-type and voltage-type active power filters, investigates the pulse width modulation technology and control strategies of current-type and voltage-type active power filters, and analyzes the performance of different active power filters in the accelerator system to suppress the output current ripple of magnet power supply. Through simulation analysis and experimental verification, it is found that the current-type active power filter has a significant suppression effect on the output current ripple of the magnet power supply, and the current-type active power filter can directly control the output ripple current, and the ripple accuracy is suppressed more highly. With the CSAPF put into use, the load current ripple is significantly reduced, and the current ripple coefficient reaches 1.6×10^–5.