Automatic grain quality testing system and implementation method

The invention discloses a grain quality automatic test system and an implementation method, the grain quality automatic test system comprises a grain screening unit, an unfreezing unit and a moisture unit, the tops of the grain screening unit, the unfreezing unit and the moisture unit are provided with a vacuum suction hopper, and the vacuum suction hopper is connected with an automatic feeding machine through a negative pressure pipeline; the automatic feeding machine provides power for grain conveying; a pneumatic three-way ball valve is arranged on a pipe section between the vacuum suction hopper and the automatic feeding machine, and suction of the vacuum suction hopper is controlled by controlling opening and closing of the pneumatic three-way ball valve; the grain screening unit is connected with the unfreezing unit through a pipeline, and the unfreezing unit is connected with the moisture unit through a pipeline, so that the perfect grain screened by the grain screening unit firstly flows into the unfr