A blade noise reduction device, comprising a plurality of sawtooth units. The plurality of sawtooth units are arranged in a first direction. Each sawtooth unit comprises secondary teeth and a primary tooth, which extend in a second direction, wherein at least one secondary tooth is distributed on each of two sides of the primary tooth, the tooth vertex angle of the secondary tooth being smaller than the tooth vertex angle of the primary tooth. The blade noise reduction device can remarkably improve the noise reduction effect. In addition, the present invention further relates to a blade having the blade noise reduction device, and a wind turbine generator set having the blade.

A serrated panel includes an attachment section having a leading edge, an attachment surface for connecting to a trailing edge of a rotor blade, a rear end, an external surface opposite the attachment surface, and a plurality of teeth. Each tooth has a tip, a base arranged at the rear end, a longitudinal axis extending from the base to the tip, a pressure side surface, and a suction side surface. The external surface of the attachment section for each tooth has a transition surface forming a transition between the leading edge and the pressure side surface. A longitudinal section in a first plane perpendicular to the attachment surface extends along the longitudinal axis of the tooth. The transition surface has a forward, concave section and a rearward, convex section. The forward, concave section is arranged nearer to the leading edge of the attachment section than the rearward, convex section.

A serrated panel is for a trailing edge of a wind turbine rotor blade. The serrated panel includes a plurality of teeth, each tooth having a tip, a base, two edges running from the tip to the base, a longitudinal axis, a pressure side surface and a suction side surface, and a plurality of vanes arranged side by side with a gap between adjacent vanes, each vane beginning at one of the edges and extending in a rearward direction. Each vane has a vane length, a vane width and a vane height. The pressure side surfaces and/or the suction side surfaces of the teeth include wave elements beginning at or near one of the edges and extending in a forward direction. Each wave element has a crest which is aligned with one of the vanes and a wave element width which is larger than the vane width.