Variable-speed turbine final stage moving vane

The present invention discloses a last stage rotor blade for a variable speed turbine, and includes a blade body, a blade root, a blade crown which are integrated into a whole; the blade body has a twisting structure in the variable section; and the width, the height and the section volume of the blade body descend from the root to the top in a smooth transition; the shape of the blade body complies with the relationship: (2being multiply with L being plus D)being multiply with f is equal to or more than 70500, or L being multiply with (L being plus D) being multiply with f is equal to or more than 5.4 being multiply with 107; T/Bd is equal or more than 0.2 and is equal to or less than 2.5; T/H1 is equal to or more than 0.55 and is equal to or less than 1.05; T/b is equal or more than 0.25 and is equal to or less than 0.85; T/d is equal or more than 2.55 and is equal to or less than 16.55, wherein L stands for the valid length of the blade body; D stands for the diameter of the rotor at the place of the blade root; f stands for the rotary rate of the rotator. Bd stands for the width of the leaf-shaped section in axel direction; Hi stands for the chord length of the leaf-shaped section; b stands for the maximum thickness of the leaf-shaped section; D stands for the volume of the leaf-shaped section; T stands for distance between two adjacent blades at the leaf-shaped section; the blade crown has a damping working surface, and the damping working surfaces of two adjacent blades are well matched and are suitable for the relationship that PX is equal to or more than 150, wherein X stands for the distance between damping working surfaces of two adjacent blades; P stands for the distance between the tops of crowns of two adjacent blades.