Abstract: A radial turbine impeller includes a turbine wheel module including a first surface and a second surface being mutually opposite in the axial direction of the radial turbine impeller. The radial turbine impeller includes blade modules attached to the turbine wheel module. Each blade module is a single piece of material and includes a body portion and blades connected to the body portion and protruding in the axial direction from the body portion. At least the first surface of the turbine wheel module is provided with one or more annular grooves opening in the axial direction and containing the body portions of the blade modules so that, in each of the grooves, the blade modules are successively in the circumferential direction. The radial turbine impeller further includes a securing system for keeping the body portions of the blade modules in the one or more grooves.

Abstract: A rotor axle of a high speed permanent magnet machine including a first part and a second part, both manufactured from a magnetically non-conducting material. The parts include an inner end and an outer end, and they can be axially interconnected one after the other by the inner ends to constitute an integral rotor axle. Their outer ends include bearing structures to fit the rotor axle with bearings. A cylindrical and solid permanent magnet is provided coaxially with the first part and the second part in between them and magnetized perpendicularly to the axial direction of the cylinder. The inner end of the first part of the rotor axle includes a cylindrical external surface with an external thread, the inner end of the second part includes a cylinder sleeve having an internal base part corresponding in shape to the cylindrical permanent magnet to constitute a space for the permanent magnet.

Abstract: A stator of an electrical machine includes a stator core having a plurality of stator teeth and stator slots, and a stator winding having a plurality of stator coils. The width of each stator coil is one stator slot pitch, and the stator teeth are shaped to allow each stator coil to be installed by pushing the stator coil to surround one of the stator teeth. The stator coils include tubular cooling channels for conducting cooling liquid in the stator slots.

Abstract: A rotor axle of a high speed permanent magnet machine including a first part and a second part, both manufactured from a magnetically non-conducting material. The parts include an inner end and an outer end, and they can be axially interconnected one after the other by the inner ends to constitute an integral rotor axle. Their outer ends include bearing structures to fit the rotor axle with bearings. A cylindrical and solid permanent magnet is provided coaxially with the first part and the second part in between them and magnetized perpendicularly to the axial direction of the cylinder. The inner end of the first part of the rotor axle includes a cylindrical external surface with an external thread, the inner end of the second part includes a cylinder sleeve having an internal base part corresponding in shape to the cylindrical permanent magnet to constitute a space for the permanent magnet.

Abstract: A stator of an electrical machine that is straightforward to assemble and for which an efficient liquid cooling can be arranged includes a stator core (801) having a plurality of stator teeth and stator slots, and a stator winding having a plurality of stator coils (803). The width of each stator coil is one stator slot pitch, and the stator teeth are shaped to allow each stator coil to be installed by pushing the stator coil to surround one of the stator teeth. The stator coils include tubular cooling channels (804) for conducting cooling liquid in the stator slots. The stator winding is designed by taking into account the aspects related to the liquid cooling, and it has been noticed that a stator winding structure which is advantageous for arranging the liquid cooling has satisfactory electrical and magnetic properties too.