The existing flexible arc extinguishing method uses only an active inverter to control the fault point voltage to zero. The arc extinguishing power supply has a capacity of up to 50 kVA and takes up a relatively large volume. To improve this, a flexible arc extinguishing method combining power source conversion and an active inverter is proposed. When a single-phase ground fault occurs, the neutral point voltage is clamped to be close to the power supply voltage of the fault phase through power source conversion, and the amplitude and phase of the deviation voltage are accurately compensated by the active inverter, so that the voltage at the fault point is much smaller than the arc extinguishing voltage. Based on a simulation of the traditional arc suppression coil using Matlab/Simulink, the operating characteristics of the flexible arc suppression method with only power source conversion, power source conversion combined with active inverters under various working conditions are simulated. The effectiveness of the method is verified by the 10 kV true distribution network test field. The results show that the flexible arc extinguishing device can effectively reduce the voltage at the fault point, realize rapid arc extinguishing, and greatly reduce the capacity of the active inverter. This work is supported by the Key Industry Innovation (Mass) Project of Shaanxi Province (No. 2019ZDLGY18-07).