An electric machine and method for cooling an electric machine Abstract There is disclosed an electric machine comprising a rotatable shaft comprising an axial channel with a first diameter D1 for receiving cooling fluid; a rotor, arranged to receive the shaft and to be fixedly connected to the shaft; a stator, arranged for mounting over the rotor; wherein the shaft comprises at least one first radial outlet at a first end, and at least one second radial outlet at a second end for allowing cooling fluid to be supplied towards the stator, wherein the channel has a dam section extending from the first end to the second end of the shaft having a second diameter D2 larger than the first diameter D1.

A non-oriented electrical steel sheet according to an embodiment of the present invention includes, in wt%, Si: 2.2 to 4.5 %, Mn: 0.5 % or less (excluding 0 %), AI: 0.001 to 0.5 %, Sn: 0.07 to 0.25 %, and N: 0.0010 to 0.0090 %, and the balance of Fe and inevitable impurities.

A surface layer portion existing in an inner direction from a surface of the steel sheet and a central portion existing inside the surface layer portion are included, and the central portion includes N at 0.005 wt% or less, and the surface layer portion further includes N at 0.001 wt% or more compared to the central portion; and the surface layer portion has an average grain size of 60 .Math.m or less, while the central portion has an average grain size of 70 to 300 .Math.m.

A rotary electric machine includes a stator including a coil, and a rotor in an inner peripheral side of the stator. The rotor core comprises a soft magnetic metal and a magnet within a magnet insertion hole, a first magnet stopper on a q axis side of the magnet in the magnet insertion hole, a magnet accommodation between the first magnet stopper on both sides of the magnet insertion hole, a first space portion communicating with the magnet insertion hole, a second space portion whose distance from the magnet is equal to or less than a thickness of the magnet and a radial length of a magnetic pole center is long, the second space portion formed on an inner peripheral side relative to the magnet, and a third space portion that has a convex shape on an inner peripheral side of a q axis of the magnet.

A cooling circuit for a vehicle includes a single cooler, a refrigeration machine, a first heat-generating device, a second heat-generating device, a coolant pump arrangement configured to pump a coolant, a valve arrangement, and an electronic control module. The first heat-generating device requires the coolant at a first coolant temperature level. The second het-generating device requires the coolant at a second coolant temperature level. The valve arrangement is configured to supply the coolant from the first and second heat-generating devices to the refrigeration machine and/or to the single cooler. The electronic control module is designed to control a temperature of the coolant at coolant inlets of the first and second heat-generating devices by varying flow rates of the coolant through the refrigeration machine and/or the single cooler.

A method for distributing a braking torque requested by a driver over the axles of a motor vehicle. The wheels of the first axle are associated with a first friction brake device and a first electrical machine having a first efficiency and the wheels of the second axle are associated with a second friction brake device and a second electrical machine having a second efficiency, in which, according to the method, the allocation of the requested braking torque over the first and/or second axle and the determination of the components of the recuperation torques to be provided by the first and/or second electrical machine of the requested braking torque is carried out taking into consideration the current driving stability of the motor vehicle.

A vehicle-mounted power supply system includes a sampling circuit, a voltage comparison control circuit, a power conversion circuit, and a motor. The sampling circuit is configured to obtain an output voltage value of an output terminal of the power conversion circuit. The voltage comparison control circuit is configured to output a first power adjustment signal to the power conversion circuit when the output voltage value is less than a first target voltage value. The power conversion circuit is configured to increase an output voltage to a first target voltage based on the first power adjustment signal, to output the output voltage to the motor and increase an input voltage of the motor. When a voltage of a power supply is low, the input voltage of the motor can be maintained at a required level.

A motor driving apparatus which drives a motor including a plurality of windings corresponding to a plurality of phases, respectively, includes: a first inverter including a plurality of first switching elements and connected to a first end of each of the windings; a second inverter including a plurality of second switching elements and connected to a second end of each of the windings; and a controller obtaining a vector corresponding to a voltage command of the motor by combining switching vectors which cause difference between a common mode voltage of the first inverter and a common mode voltage of the second inverter to be zero and configured to control the plurality of first switching elements and the plurality of second switching elements in a pulse width modulation method based on the obtained vector.

A drive unit includes an electric motor, an MCU to supply a driving current to the electric motor, and a bracket fixing the MCU to the electric motor with a gap between the MCU and the electric motor. The electric motor includes a stator case accommodating a stator, a first housing including a bearing that supports one side of an output shaft of a rotor, and a second housing including a bearing that supports another side of the output shaft of the rotor. The bracket supporting the MCU is attached to the first housing and the second housing and not to the stator case.

A repair method of a stator iron core which has a slot for accommodating a stator coil, and is formed by laminating silicon steel sheets. The method is implemented by moving a part of the silicon steel sheets which form the stator iron core while holding the stator coil in the slot to form a gap between the laminated silicon steel sheets of the stator iron core in the existence of a damaged part, and adding an insulation to the damaged part of the silicon steel sheet from the gap formed between the laminated silicon steel sheets to repair the damaged part of the silicon steel sheet.

A method for protecting an electric machine of a motor vehicle, In the method, a switch-on frequency for the electric machine is ascertained as a function of operating parameters of the motor vehicle stored in a control unit. The switch-on frequency is compared to a predefinable first threshold value. At least one further threshold value is preset. The electric machine is switched on in the event a control variance exceeds the at least one further threshold value. In the event the switch-on frequency exceeds the first predefinable threshold value, the at least one further threshold value is adapted in such a way that the switch-on frequency of the electric machine is limited.