Closed pump electric skid-mounted sand mixer

The utility model relates to a closed pump electric skid-mounted sand mixer. The closed pump electric skid-mounted sand mixer comprises a closed pump device, a pipeline system, a dry adding system, a liquid adding system, a fiber adding system, an electric control gear and a skid rack. A driving variable frequency motor supplies power to the closed pump device, and sand mixing is conducted inside the closed pump device. The pipeline system is used for sucking and discharging fracturing base fluid and mixed fracturing fluid, and the pipeline system is communicated with the closed pump device. The dry adding system, the liquid adding system and the fiber adding system are communicated with the closed pump device and are adjustable in adding speed. The dry adding system, the liquid adding system and the fiber adding system are used for adding dry adding drugs, fracturing fibers and liquid adding drugs respectively. The electric control gear is connected with all the systems and the closed pump device and can con