Analysis of helical armature windings with particular reference to superconducting a.c. generators

Abstract

An unusual form of polyphase armature winding is described in which conductors lie on a helix of constant radius as they pass from one end of the machine to the other. There are no end windings. An analysis of the winding is performed which allows analytical expressions for the flux densities and machine reactances to be found. Measured and calculated values of synchronous reactance agree to within 2%. Some of the more unusual properties of helical windings are discussed.