Internal stop valve of turbine

The invention aims to provide an internal stop valve of a turbine. The internal stop valve comprises a turbine shell, a volute, an electric motor, a drive rod, a guide rod, and a valve; the volute is fixed on the turbine shell, and the valve is arranged in the turbine shell; the end part of the valve is arranged to be a trapezoid, and an entrance of the volute is provided with a trapezoid groove matched with the end part of the valve; the valve is fixedly connected with the guide rod, and the guide rod is extended out of the outer part of the turbine shell and connected with the drive rod; a rack is arranged on the drive rod, the electric motor connects and drives a gear, and the gear is meshed with the rack. Through a stepping motor, opening and closing of the valve are controlled; the response speed is quick; the free cut-in and cut-out of a booster can be realized; the sealing face consisting of the trapezoid groove and the valve can realize good sealing function besides, the trapezoid groove within a certain processing bias and the installing bias can automatically position the valve closing.