This method of manufacturing a stator includes a step of removing insulating coatings on first surfaces of lead wire portions that are surfaces to be welded, and a step of welding together the first surfaces by a green laser with the insulating coatings on the first surfaces being removed and with insulating coatings on second surfaces opposite the first surfaces being unremoved.

Disclosed is a stator assembly machining system. The stator assembly machining system configured to perform a series of processes for machining a plurality of hairpins by receiving a stator assembly includes a stator assembly loading part, a hairpin cutting part configured to perform a cutting process of an end part of each of the plurality of hairpins, a hairpin welding part configured to perform a welding process of the end part of each of the plurality of hairpins, a stator assembly unloading part configured to unload the stator assembly supplied from the hairpin welding part, and a stator assembly transfer part configured to transfer the stator assembly to the stator assembly loading part, the hairpin cutting part, the hairpin welding part, and the stator assembly unloading part while supporting the stator assembly, wherein the stator assembly transfer part includes a stator assembly transfer jig, and a jig transfer rail.

A stator assembly is provided that includes a stator core and stator windings having a U-phase winding, a V-phase winding, and a W-phase winding. An n-number of stator slots are on an inner circumferential surface of the stator core, each stator slot is divided into an m-number of accommodating layers along a radial direction of the stator core, the U-phase winding is laid in the stator slot and is arranged in the same layer in an m-th accommodating layer and arranged across layers in other accommodating layers, n is a multiple of 6, and m is an odd number greater than 3. The U-phase winding includes first and second branch windings formed by connecting the same number and type of coils in series; the V-phase winding is obtained by rotating the U-phase winding clockwise by 120, and the W-phase winding is obtained by rotating the U-phase winding clockwise by 240.

A method for reworking a defective welded connection of a hairpin winding for a rotor or stator of an electrical machine, including providing the hairpin winding applied to a winding support. The hairpin winding has at least one conductor formed from multiple conductor sections. The conductor sections of the respective conductor are welded in pairs at a respective welded connection by a first welding method, and at least one of the welded connections is a defective welded connection. The defective welded connection is severed, and the conductor sections to be welded, which were previously connected by the defective welded connection, are connected by way of a connecting method that differs from the first welding method.

A method of welding and evaluating welds on stator hairpins includes obtaining first data representative of the ends of a first pair of stator hairpins by capturing image data representative of the ends, and processing the image data to obtain a data set representative of a rectangle which fully encloses the end surfaces of the stator hairpins. After the data set is saved, a laser may be used to form a weld on the end surfaces of the stator hairpins. Then, second data is obtained representative of the weld, and the weld is evaluated by comparing the second data to the data set. A system for welding and evaluating welds on the ends of stator hairpins is also disclosed. A digital camera may be used to capture data, and the laser may be used to form the welds on the stator hairpins.

A method of welding and evaluating welds on stator hairpins includes obtaining first data representative of the ends of a first pair of stator hairpins by capturing image data representative of the ends, and processing the image data to obtain a data set representative of a rectangle which fully encloses the end surfaces of the stator hairpins. After the data set is saved, a laser may be used to form a weld on the end surfaces of the stator hairpins. Then, second data is obtained representative of the weld, and the weld is evaluated by comparing the second data to the data set. A system for welding and evaluating welds on the ends of stator hairpins is also disclosed. A digital camera may be used to capture data, and the laser may be used to form the welds on the stator hairpins.

A rotating electrical machine includes segmented coils respectively disposed in layers aligned in a row in a radial direction inside a slot of a stator core. The segmented coils include first regions having a straight line section disposed inside the slot and a protrusion protruding to the outside of the slot from one end of the straight line section, and second regions extending toward one side in the circumferential direction from the other end of the respective straight line section, such that the position in the radial direction changes. The tip end section of the second region of a first segmented coil disposed in a prescribed layer within a prescribed slot is disposed and connected to be adjacent, in the radial direction, to the tip end section of the first region of a second segmented coil disposed in the prescribed layer within a slot adjacent to the prescribed slot.

A rotating electrical machine includes segmented coils respectively disposed in layers aligned in a row in a radial direction inside a slot of a stator core. The segmented coils include first regions having a straight line section disposed inside the slot and a protrusion protruding to the outside of the slot from one end of the straight line section, and second regions extending toward one side in the circumferential direction from the other end of the respective straight line section, such that the position in the radial direction changes. The tip end section of the second region of a first segmented coil disposed in a prescribed layer within a prescribed slot is disposed and connected to be adjacent, in the radial direction, to the tip end section of the first region of a second segmented coil disposed in the prescribed layer within a slot adjacent to the prescribed slot.

Rotors and stators for use in electric machines and methods for refurbishing the same. One method for refurbishing a stator for use in an electric machine includes at least partially disassembling the stator to provide access to a plurality of stator windings connected in a four-circuit delta connection having three and four turns per coil, and reconfiguring the stator such that the plurality of stator windings are connected in an eight-circuit delta connection having seven turns per coil. One method for refurbishing a rotor for use in an electric machine includes at least partially disassembling the rotor to provide access to a rotor core, the rotor core including first rotor bars, and reconfiguring the rotor core to include second rotor bars that are longer than the first rotor bars.

Rotors and stators for use in electric machines and methods for refurbishing the same. One method for refurbishing a stator for use in an electric machine includes at least partially disassembling the stator to provide access to a plurality of stator windings connected in a four-circuit delta connection having three and four turns per coil, and reconfiguring the stator such that the plurality of stator windings are connected in an eight-circuit delta connection having seven turns per coil. One method for refurbishing a rotor for use in an electric machine includes at least partially disassembling the rotor to provide access to a rotor core, the rotor core including first rotor bars, and reconfiguring the rotor core to include second rotor bars that are longer than the first rotor bars.