The invention relates to a cooling channel for a winding head of an electric machine, where the cooling channel is formed to be annular for guiding a cooling fluid with at least one inflow and at least one outflow and for being arranged around the winding head. With the aim of an improved sealing property, the cooling channel comprises an axially movable pressing member which is arranged such that a cooling fluid can flow onto the pressing member and a pressing force against the cooling channel can be generated.

A rotating electrical machine includes a rotor and a stator. A first end plate includes a first refrigerant discharge hole which communicates with a second refrigerant flow path hole and supplies refrigerant to a first coil end and a first groove portion which supplies the refrigerant supplied from a refrigerant flow path to a first refrigerant flow path hole and does not supply the refrigerant to the first refrigerant discharge hole and the second refrigerant flow path hole. A second end plate includes a second refrigerant discharge hole which supplies the refrigerant to a second coil end and a second groove portion which supplies the refrigerant supplied from the first refrigerant flow path hole to the second refrigerant flow path hole and supplies the refrigerant to the second refrigerant discharge hole.

A motor drive apparatus includes a motor, a power converter, and a controller that controls the voltage supplied to the motor by the power converter. The power converter converts a voltage of a 400 V-class AC power supply to a voltage with an effective value lower than an effective value of the 400 V-class AC power supply. The power converter converts the voltage by a switching operation of a plurality of switching elements. The motor is configured so that a value of φ×Vx/Ld is greater than Pmax when an effective value voltage Vx=200 V. A d-axis inductance of the motor is Ld. A flux linkage of the motor is φ. A maximum output of the motor in a device where the motor is mounted is Pmax. The controller has a control mode in which an effective value voltage higher than Vx is applied to the motor.

A drive train (100) has an electric machine (1) with a stator (2), an inverter (3) and a connection housing (4) with a coolant chamber (4.1) in which an electric conductor (5) for connecting a directly liquid-cooled stator winding (2.2) of the stator (2) to the inverter (3) is arranged. The coolant chamber (4.1) is open in a liquid-permeable manner toward a stator chamber (2.1) of the stator (2) at an opening (4.3). The electric conductor (5) is guided out of the coolant chamber (4.1) to the inverter (3) at a leadthrough (4.2), and the leadthrough (4.2) is sealed in a liquid-tight manner. A motor vehicle (200) with the drivetrain (100) also is provided.

Various methods and systems are provided for a system for cooling an electric motor. The cooling system includes a primary coolant passage through a rotor shaft linked to a plurality of secondary passages though lamination stacks of a rotor configured to receive coolant at a central region of the lamination stacks.

A drive includes an electric motor with a brake and a fan cowl. The fan cowl is connected to a housing, in particular to a stator housing part, of the electric motor in a detachable manner. A rod is able to be passed through a cover part, which projects through a recess, in particular a recess arranged in the form of a slot, in the fan cowl.

A motor system includes: a motor including: a motor housing, a stator core, a stator winding, and a rotor core, the stator core mounted in the motor housing, the stator winding wound around the stator core, the rotor core rotatably disposed with respect to the stator core, a rotor flow path formed at least in the rotor core, the rotor flow path configured to transport coolant to the stator winding; and a valve configured to control a flow of the rotor flow path.

A motor drive apparatus includes a motor, a power converter, and a controller that controls the voltage supplied to the motor by the power converter. The power converter converts a voltage of a 400 V-class AC power supply to a voltage with an effective value lower than an effective value of the 400 V-class AC power supply. The power converter converts the voltage by a switching operation of a plurality of switching elements. The motor is configured so that a value of φ×Vx/Ld is greater than Pmax when an effective value voltage Vx=200 V. A d-axis inductance of the motor is Ld. A flux linkage of the motor is φ. A maximum output of the motor in a device where the motor is mounted is Pmax. The controller has a control mode in which an effective value voltage higher than Vx is applied to the motor.

The invention relates to a fluid-cooled active part (1) for an electric machine (38), wherein the active part (1) is substantially cylindrical or hollow cylindrical, having axially extending grooves (2), at least one electrical conductor (3), which is arranged in the associated groove (2) at least in some sections and which is composed of a plurality of partial conductors (4), one or more main insulators (5), each arranged between the associated conductor (3) and the associated groove (2), and partial-conductor insulators (6), each surrounding the associated partial conductor (4). The invention further relates to an electric machine (38), having such a fluid-cooled active part (1) designed as a stator (39) and/or such a fluid-cooled active part (1) designed as a rotatably mounted rotor (40), wherein the electric machine (38) can be operated with a voltage in the range of at least a few kilovolts, preferably a few tens of kilovolts. Finally, the invention relates to a drive System (41), having such an electric machine (38) and a fluid energy machine (42) for the fluid, wherein the fluid energy machine (42) is designed as a compressor, in particular for process gas, or as a pump, in particular for a process liquid. In order to provide, among other things, a high-performance fluid-cooled active part that is compact and, in particular, resistant in the environment of the fluid or of a process fluid, it is proposed, among other things, that the active part (1) has one or more cooling Channels (7) for conducting the fluid, in particular a process fluid, wherein each cooling Channel (7) is arranged between the associated main insulator (5) and the respective partial-conductor insulators (6).

The cooling device is intended for an electric motor and has a rotor cooling flange and a stator cooling flange (2), of which one is rotatable with respect to the other. At least one of the two cooling flanges (2) is provided with cooling ribs (8) arranged distributed over its circumference. During operation of the electric motor, at least one of the two cooling flanges gives off heat to the surrounding air. At least some of the cooling ribs (8) of a heat-emitting cooling flange (2) have an undulating profile over their length. In this context, the surface area of a cooling rib (8) having an undulating profile is larger than the surface area of the associated straight reference rib.