In order to meet the reliable ignition of the gas switch with longer distance working in higher working voltage

an atmospheric plasma ejector based on capillary discharge is presented

which is named as TGC（Two Gap Capillary）. By introducing the middle electrode

the capillary is divided into the trigger gap and the main gap. At the beginning of the discharge

the trigger gap is flashed under the high-voltage pulse and the soft capillary discharge begins. Thus

repetitive discharge is achieved. The length of the plasma flow is close to 11 cm after 169 μs of the triggering. The waveform of the main gap resistance during the discharge seems to be U-shape

of which the minimum value is less than 200 m?. The main gap resistance decreases rapidly in the preliminary stage of the discharge and rises with the shrink of the current. In addition

the resistance is considerably higher as the current increases than decreases

which is particularly markable when the current is not high enough and disappears gradually with the growth of the current. Without the process of the wire explosion

there is about 62.7% of the energy stored in the capacitor consumed on the main gap and the energy deposition efficiency on main gap is approximately 2 times higher than that of the traditional structure. The mean life of the TGC is about 300 times. With the aid of the SEM

it is found the erosion of the middle electrode and trigger gap carbonization are the key factors that limit the life performance of the TGC

which still needs further research.