Abstract: A method for Roebel transposition of form wound conductors for electrical machines is disclosed which creates less distortion of strand geometry and more efficiently stacks the conductor strands. The transposition involves four stacks of conductors, where two conductor strands from a top position in the first two adjacent stacks of conductors are transposed side-by-side two places to a top position in the other two adjacent stacks of conductors, with a corresponding downward shift in the second two stacks and upward shift in the first two stacks. Compared to a traditional Roebel pattern involving only two stacks of conductors and transposing two vertically-adjacent strands, the four-stack side-by-side Roebel transposition method produces a stack height which is reduced by one strand, and reduces the likelihood of strand-to-strand short circuits because of the smoother transition geometry involved.

Abstract: The present invention provides for thin sheet wedges that comprise a mica matrix impregnated with a conductive resin. The mica matrix is composed of mica flakes. The thin sheet wedge has a semi-conductive property of 500–500,000 ohms per square. In one embodiment the thin sheet wedge further comprises at least one glass fiber layer. In a particular embodiment the glass fiber layer is a backing for the mica matrix. In another particular embodiment the glass fiber is interwoven with the mica matrix. The glass fiber layer may itself be impregnated with a conductive resin.