Design and testing of a belt-driven induction starter-generator

The advent of higher voltages in automobiles constitutes an opportunity for new electrical features and systems. In that regard, a combined starter-generator would have several important benefits, most notably it would enable the turning off of the engine at idle and provide efficient, high power generation, both resulting in improved fuel economy. Several ongoing starter-generator projects have focused on locating the starter-generator around the engine flywheel. This paper describes the design of a belt-driven alternative with an induction machine drive. The proposed system would be easier to package than a flywheel-mounted system, since it would not affect the overall length of the powertrain. The paper presents various models as well as test results from a prototype system. Some specific implementation issues, such as induction generator stability at high speed, are also explored in some depth.