Inside virtual analogue means that discharges that connects of closed end screen protection casing of oil paper electric capacity sleeve pipe relates to transformer outgoing line sleeve pipe insulation test device, has solved sleeve pipe prophylactic test and can cause the latent lesion of end screen terminal and can not control incipient discharge voltage and the problem of the electric quantity that discharges. The utility model provides a protection casing arch is fixed in hollow end screen protection casing upper end, the polytetrafluoroethylene sheath is fixed inside the screen protection casing of hollow end, the one end of adjustable electrode just is fixed with no. One flat electrode inside stretching into hollow end screen protection casing behind the axle center through -hole of protection casing arch, hollow end screen protection casing and polytetrafluoroethylene sheath, no. Two flat electrode and a flat electrode among the screen terminal guard electrode of end are corresponding, electrode distance fastening dish threaded connection is on the threaded rod of adjustable electrode, and the bottom surface of this electrode distance fastening dish and the bellied upper surface in close contact with of protection casing. The utility model is suitable for a virtual simulation experiment that discharges that connects of sleeve pipe end screen terminal.