Method for converting non-pressure water delivery into pressure water delivery in middle-small sized hydropower station plant

The invention relates to a method for converting non-pressure water delivery into pressure water delivery in a middle-small sized hydropower station plant, and belongs to the technical field of hydropower station plant buildings. The method comprises the steps that the hydropower station plant is built at the downstream flat position of an upstream water intake structure firstly; a conversion chamber is built at the position close to the hydropower station plant; the conversion chamber is provided with an overflow port which is connected to a nearby water channel or flood spillway through a drain pipe; the bottom of the conversion chamber is provided with a port I; a hydraulic turbine set inn the hydropower station plant is connected with a water delivery pressure steel pipe through a port II; a non-pressure head race can be excavated along the edge of a mountain to avoid excavation of a pressure tunnel, slope protection is performed on both sides of the non-pressure head race through cement laid stone masonr