In order to improve the reliability and convenience of the voltage-reduction arc suppression device, a zero-sequence voltage flexible control method based on line voltage series modulation damping grounding is proposed, and its application in arc suppression and feeder protection is studied. First, based on the advantage that the line voltage of the distribution network is not affected by single-phase grounding fault, an active grounding device replacement scheme using isolation transformer, arc suppression coil, and other traditional passive devices is proposed, which has the advantage of flexibly regulating the amplitude and phase of zero sequence voltage. Then, the impact of the asymmetric distribution parameters on the active arc suppression is demonstrated, and an arc suppression control method based on full compensation of fundamental current is proposed. Furthermore, a fault phase voltage active lifting method with line voltage access is proposed to effectively improve the detection sensitivity of high resistance faults. Finally, the optimal selection scheme of the accessed line voltage and modulation damping is analyzed, and the integrated control scheme of fault arc suppression and feeder protection in distribution network is given, whose effectiveness is validated by simulation experiment. In practical application, the equipment cost can be reduced only by connecting the selected line voltage to the neutral point through the isolation transformer and cooperating with the resistive modulation damping, which improves the reliability and control convenience of equipment, and provides a new scheme for the grounding fault feeder protection and zero residual current fault arc elimination of the distribution network.