Stator assembly, a hairpin winding motor including the same, and a method of winding stator coil of a hairpin winding motor

A hairpin winding motor comprising a stator assembly,

• wherein the stator assembly comprises:
• a stator core having a plurality of slots formed in a circumferential direction thereof, wherein the plurality of slots is disposed on an inner circumferential portion of the stator core;
• and
• a coil winding part having hairpins respectively inserted into the plurality of slots of the stator core, wherein the hairpins are connected in series to form a coil for each of a U-phase, a V-phase, and a W-phase,
• wherein:
• each of the plurality of slots has a space partitioned into a plurality of layers arranged in a radial direction of the stator core,
• the coil for each of the U-phase, the V-phase, and the W-phase comprises a first half-coil winding and a second half-coil winding formed by connecting the respective hairpins in series,
• two layers adjacent to each other inwards and outwards in the radial direction of the stator core in each slot are defined as a set,
• the first half-coil winding and the second half-coil winding of the coil of each phase comprise coil windings for the respective sets formed by connecting in series the hairpins respectively inserted into the layers in the same set in the plurality of slots,
• the coil windings for the respective sets are connected in series with a coil winding of another neighboring set by a jumper to form the first half-coil winding and the second half-coil winding, and
• wherein the jumper comprises:
• a first jumper having a y-pitch interval, wherein the first jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the y-pitch interval in the circumferential direction of the stator core,
• a second jumper having a (y−1)-pitch interval, wherein the second jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the (y−1)-pitch interval in the circumferential direction of the stator core, and
• a third jumper having a (y+1)-pitch interval, wherein the third jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the (y+1)-pitch interval in the circumferential direction of the stator core.

A method of winding a stator coil of a hairpin winding motor, the method comprising:

• providing a stator core having a plurality of slots formed in a circumferential direction thereof, wherein the plurality of slots is disposed on an inner circumferential portion of the stator core;
• partitioning a space in each slot of the plurality of slots into a plurality of layers arranged in a radial direction of the stator core;
• and
• respectively inserting hairpins into the plurality of slots of the stator core, and performing stator coil winding to connect the hairpins inserted thereinto in series to form a coil for each of a U-phase, a V-phase, and a W-phase,
• wherein:
• the coil for each of the U-phase, the V-phase, and the W-phase comprises a first half-coil winding and a second half-coil winding formed by connecting the respective hairpins in series,
• two layers adjacent to each other inwards and outwards in the radial direction of the stator core in each slot are defined as a set,
• the first half-coil winding and the second half-coil winding of the coil of each phase comprise coil windings for the respective sets formed by connecting in series the hairpins respectively inserted into the layers in the same set in the plurality of slots, and
• he coil windings for the respective sets are connected in series with a coil winding of another neighboring set by a jumper to form the first half-coil winding and the second half-coil winding, and
• wherein the jumper comprises:
• a first jumper having a y-pitch interval, wherein the jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the y-pitch interval in the circumferential direction of the stator core,
• a second jumper having a (y−1)-pitch interval, wherein the jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the (y−1)-pitch interval in the circumferential direction of the stator core, and
• a third jumper having a (y+1)-pitch interval, wherein the jumper connects the coil windings of different sets wound in the two slots spaced apart from each other by the (y+1)-pitch interval in the circumferential direction of the stator core.