Design and characterization of a cost-effective and high-power density brushless rotor supply for mobile synchronous generators

As part of the ongoing NGC-project (Next Generation Car) related to the research of new technologies for future road vehicles at the DLR, this publication is dedicated to the replacement of slip rings by an inductive power transfer system for field winding supplies in electrically excited synchronous generators. By means of function integrated lightweight design, due to the attachment of the rotary transformer as well as the co-rotating rectifier on an existing fan and the usage of standardised components for the rotational transformer, a volumetric optimized mounting as well as cost-effective brushless transfer system can be realized. The design of the system regarding the integration into the constraint space includes a variety of different challenges, which are subject of this work. For design purpose, an analytical model of the inductive link, the compensation network as well as the primary and secondary side power electronics has been set up. Furthermore, a prototype system has been established, measured on the test bench at the institute of vehicle concepts and compared to the derived model.