High-Speed Electric Drive for Exhaust Gas Energy Recovery Applications

High-speed electric drives play an important role in the field of power generating units on board vehicles and aircrafts. This paper deals with the solutions for developing the direct coupled electric drive to be used in combination with a radial turbo-expander for exhaust energy recovery in automotive applications. The descriptions of prototypal realization of both the axial-flux permanent-magnet (PM) generator and the three-level boost-rectifier converter, which results as the preferred topology for the controlled rectifier, are given. The high rotational speed of the direct-driven PM generator results in high electric fundamental frequency also, which is challenging for the electric drive control issues. Results of the electric drive prototype experimental activity are finally presented.