Patent ID: 7977826

Claim:
A permanent-magnet synchronous machine, comprising: a rotor; and a stator having no more than six slots, with each of neighboring ones of the slots defining a tooth, and a winding system having no more than three tooth-wound coils, each of the tooth-wound coils associated with a different winding phase and encompassing a single tooth, with a tooth having a tooth-wound coil alternating with a tooth without a tooth-wound coil in a circumferential direction of the stator; a slot closure element constructed in the form of a slit tube having, said slit tube having circumferentially contiguous annular end sections connected by axially extending lands configured for axial insertion into the slots, wherein the lands of the slot closure element have a wall thickness dimensioned so as not to protrude into an air gap formed between the stator teeth and the rotor, and wherein an annular end section has recesses formed externally along an external periphery of the end section commensurate with peripheral arrangement of the stator teeth and a radial depth dimensioned for passage of the end section over the stator teeth, wherein a useful rotor pole pair number is four or five, and the rotor comprises permanent magnets distributed uniformly over a circumference of the rotor, with a number of the permanent magnets being equal to twice the useful pole pair number.