With the implementation of a "carbon peak and carbon neutral" strategy, in new power systems, since the large rotating generators need to shoulder the responsibility of necessary power regulation and stable power support, their safe and stable operation is important. For the most prone stator ground faults, it is important to restrain the arc damage and avoid the impact of rigidly cutting the generators. In this paper, a method of ground fault arc suppression and fault current limiting is proposed based on dual-frequency active regulation for large generators. This can cure the transient faults, and limit the fault current to ensure the stator iron core safety for permanent faults. An adaptive ground fault protection method cooperating with active arc suppression is proposed, and this can realize flexible generator tripping control, and improve the safety of the generator and the power grid. The effectiveness of the proposed method is verified by simulation and dynamic test. Its arc suppression and fault current limiting effects are better than the existing passive arc suppression methods.