Integrating the magnetics of an LCL filter into a high speed machine with pre-compressed coils

Abstract

This paper presents a high speed electric machine with integrated magnetics of the grid side LCL filter. The integrated drive has been designed to take full advantage of sharing the machine stator structure for volume reduction. The main outcome of this paper is the ability to integrate all six LCL filter inductors into the proposed machine by sharing the original machine's magnetic circuit without magnetic cross-coupling between the integrated filter inductor windings or with the main machine magnetic circuit. Both the main machine coils and the filter inductor coils are pre-compressed directly onto the double slot stator teeth to form a solid component with fill factors for the main machine and filter windings of 60% and 50% respectively. The use of a segmented stator enabled rapid and repeatable construction of the proposed geometry. This paper presents a number of novel electromagnetic design and manufacturing processes which enhance the performance and functionality of the integrated drive concept.