A motor stator comprising: a core comprising a plurality of slots, an insertion side and an extension side opposite to the insertion side, wherein each slot comprises a first layer, a second layer, a third layer, a fourth layer, a fifth layer and a sixth layer, configured from outer to inner in a radial direction of the core; a plurality of first hairpin wires, each first hairpin wire comprising a first hairpin first leg and a first hairpin second leg, wherein each first hairpin first leg is inserted into the third layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a first direction, wherein each first hairpin second leg is inserted into the sixth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a second direction; a plurality of second hairpin wires, each second hairpin wire comprising a second hairpin first leg and a second hairpin second leg, wherein each second hairpin first leg is inserted into the fourth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a third direction, wherein each second hairpin second leg is inserted into the fifth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a fourth direction; and a plurality of third hairpin wires, each third hairpin wire comprising a third hairpin first leg and a third hairpin second leg, wherein each third hairpin first leg is inserted into the first layer of the slots and each third hairpin second leg is inserted into the second layer of the slots, characterized by: wherein each first hairpin first leg is connected with the immediately-adjacent first hairpin second leg, second hairpin first leg and second hairpin second leg to form a first winding set, wherein the first direction and the third direction are of the same circumferential direction, the second direction and the fourth direction are of the same circumferential direction, and the first direction is opposite to the second direction. a core comprising a plurality of slots, an insertion side and an extension side opposite to the insertion side, wherein each slot comprises a first layer, a second layer, a third layer, a fourth layer, a fifth layer and a sixth layer, configured from outer to inner in a radial direction of the core; a plurality of first hairpin wires, each first hairpin wire comprising a first hairpin first leg and a first hairpin second leg, wherein each first hairpin first leg is inserted into the third layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a first direction, wherein each first hairpin second leg is inserted into the sixth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a second direction; a plurality of second hairpin wires, each second hairpin wire comprising a second hairpin first leg and a second hairpin second leg, wherein each second hairpin first leg is inserted into the fourth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a third direction, wherein each second hairpin second leg is inserted into the fifth layer of the slots from the insertion side and protruded out of the slots from the extension side and bent in a fourth direction; and a plurality of third hairpin wires, each third hairpin wire comprising a third hairpin first leg and a third hairpin second leg, wherein each third hairpin first leg is inserted into the first layer of the slots and each third hairpin second leg is inserted into the second layer of the slots, characterized by: wherein each first hairpin first leg is connected with the immediately-adjacent first hairpin second leg, second hairpin first leg and second hairpin second leg to form a first winding set, wherein the first direction and the third direction are of the same circumferential direction, the second direction and the fourth direction are of the same circumferential direction, and the first direction is opposite to the second direction. wherein each first hairpin first leg is connected with the immediately-adjacent first hairpin second leg, second hairpin first leg and second hairpin second leg to form a first winding set, wherein the first direction and the third direction are of the same circumferential direction, the second direction and the fourth direction are of the same circumferential direction, and the first direction is opposite to the second direction.