Method and apparatus for fluid flow control

摘要

Methods and apparatus are provided for modulating a flow of fluid in a duct using a rotating member that rotates in the duct. A sensing unit senses the rotation speed of the rotating member and generates a rotation signal as a function of the sensed rotation speed. A control unit receives the rotation signal from the sensing unit and generates a control signal to modify the rotation speed of the rotating member. The apparatus can be self-powering by generating an electric current in response to rotation of the blade.