Abstract: To address the issues of insufficient compensation capability in traditional passive arc suppression methods and the high cost of existing active arc suppression techniques for single-phase grounding faults in distribution networks, this paper proposes a flexible arc suppression method based on non-fault phase voltage injection. This method does not require ground parameter measurements. By selecting any non-fault phase as the injection phase and forcibly adjusting its phase-to-ground voltage, the touch voltage and step voltage at the fault point are driven close to zero, thereby effectively suppressing overvoltage and ensuring personal and equipment safety as well as power supply reliability. Simulation results from MATLAB/Simulink and prototype tests conducted in a 10 kV physical experimental field demonstrate the feasibility of the proposed method. Based on the principle that the magnitude and phase of line-to-line voltages remain unchanged during a single-phase grounding fault, arc extinction is achieved by injecting a phase-to-ground voltage without requiring a neutral point from a grounding transformer. The system can be installed either at the station busbar or on distribution lines, offering considerable cost advantages and high flexibility.