Micro-turbo-generator design and fabrication: a preliminary study

This paper discusses the design and fabrication issues associated with the creation of a micro-turbo-generator. The design involves the coupling of an impulse turbine to a switched reluctance generator via a single rotor which couples the two systems. The force of the gas on the rotor causes it to turn at high speeds. With proper current switching and control, this motion can be converted into an electrical power output. A parametric finite element model of the device was created in ANSYS to study its electromechanical performance and to determine the torque that would be required of the micro-turbine. A micro-turbine was fabricated to demonstrate the mechanical portion of this energy conversion system. A planar device was created using the LIGA fabrication technique in which all structures were electroplated copper. Experiments were conducted on five working micro-turbines. The variables studied included the stator design, rotor pole shape, device orientation and the distance between the rotor and the device cover.