Abstract: An electric motor includes a shaft, a rotor, a stator, a first bracket, a second bracket, a heat exchanger, a first guide, and a second guide. The heat exchanger includes an internal air bypass located radially outward from the internal air passage of the stator, and an external air bypass located radially outward from the internal air bypass and continuous to the external space. The heat exchanger further includes a heat transfer member to separate the internal air bypass and the external air bypass, and transfer heat from the internal air flowing in the internal air bypass to the external air flowing in the external air bypass.

Abstract: The drive system includes a motor, a power converter, and a controller. The motor is a reluctance motor that rotates in response to feeding of electric power. The power converter includes multiple switching elements and is connected directly to the motor. The power converter converts electric power fed from a power source into electric power to be fed to the motor and feeds the converted electric power to the motor. The controller controls the switching elements included in the power converter.

Abstract: An electric motor includes a shaft supported rotatably about a rotation axis, a rotor located outward from the shaft in a radial direction of the shaft and rotatable integrally with the shaft, a stator facing the rotor in the radial direction, and a first bracket including an inlet to draw air into the electric motor from outside. The electric motor further includes a fan rotatable integrally with the shaft and having a first through-hole at a position facing a position inward from the inlet in the first bracket in the radial direction, and a first guide being cylindrical and facing the first bracket.

Abstract: An air intake port has an opening part and an air intake port cover forming an air flow channel from the opening part to the air intake port. The air intake port cover has a guide plate to block the opening part and the air intake port from each other and leave an air flow path between the guide plate and an outer perimeter surface facing a vehicle body, a discharge port formed in the outer perimeter surface, a discharge port cover separating the discharge port and the air intake port from each other, and leaving an air flow path from the opening part to the discharge port, and a pair of cylindrical members, one end of each being connected to two holes formed in the discharge port cover, and the other ends facing each other in a travel direction, and tapering in cross-sectional area.

Abstract: A three-phase induction motor includes: a stator having a stator slot having an open slot structure for inserting a formed coil; and a rotor having a rotor slot into which a conductor bar is inserted, the rotor being placed on an inner side of the stator with a clearance between the rotor and the stator. The conductor bar has a polygonal cross-sectional shape having six or more angles, and both end portions of an outer-circumference-side edge surface of the conductor bar are rounded.

Abstract: A three-phase induction motor that is rotationally driven in response to supply of AC power from an inverter including a switching element formed by using a wide bandgap semiconductor includes: a stator including a stator slot having an open slot structure for inserting a former-wound coil; and a rotor including a rotor slot into which a secondary conductor is inserted, the rotor being disposed inside the stator via a gap. Assuming that the number of rotor slots is Nr, the number of stator slots is Ns, and the number of poles is Np, Nr, Ns, and Np are set such that the relationship of Nr?Ns?Np?6 is satisfied.

Abstract: A vehicle main electric motor includes: a ring-shaped filling chamber, which is formed in contact with a ball bearing and a roller bearing in a direction of a rotation shaft, for filling with a semi-solid lubricant, and which has a central axis concentric with the rotation shaft; and a discharge section connected to the filling chamber, for inflow of the semi-solid lubricant from the filling chamber. A display member, which has a specific gravity lower than a specific gravity of the semi-solid lubricant, is arranged, in an interior of the discharge section, at an initial position that is a position not reached by the semi-solid lubricant during an initial greasing. The discharge section has a retaining part for retaining, at a movement position that is a determined position within the discharge section, the display member moving in a greasing direction due to pressure of the semi-solid lubricant during a supplemental greasing.

Abstract: A vehicle main electric motor includes: a ring-shaped filling chamber, which is formed in contact with a ball bearing and a roller bearing in a direction of a rotation shaft, for filling with a semi-solid lubricant, and which has a central axis concentric with the rotation shaft; and a discharge section connected to the filling chamber, for inflow of the semi-solid lubricant from the filling chamber. A display member, which has a specific gravity lower than a specific gravity of the semi-solid lubricant, is arranged, in an interior of the discharge section, at an initial position that is a position not reached by the semi-solid lubricant during an initial greasing. The discharge section has a retaining part for retaining, at a movement position that is a determined position within the discharge section, the display member moving in a greasing direction due to pressure of the semi-solid lubricant during a supplemental greasing.

Abstract: A traction motor comprises a stator, a rotor core, an iron core holder, a cooling fan, a rotor, a frame, a bracket, and a bearing unit. The cooling fan includes a main plate that separates the inside and the outside of the totally-enclosed traction motor; blades provided on the bracket side of the cooling fan and along a rotational direction of the rotor; and a guide provided on the bracket side of the blades. In the bracket, inlets are provided within an area obtained when the guide is projected onto the bracket. The guide is formed such that air drawn in through the inlets is guided to a rotor shaft.

Abstract: The main motor for a railway vehicle is rotationally driven upon receiving an AC power supplied from an inverter circuit that includes a switching element formed by using a wide bandgap semiconductor. The inverter circuit applies a voltage having a PWM waveform to the main motor for a railway vehicle in at least part of a speed range of an electric vehicle. The stator of the main motor for a railway vehicle is configured to include an annular stator core provided with a plurality of slots in a circumferential direction and coils that are wound on the stator core and are accommodated in the slots, and includes a stator winding that is three-phase star-connected and is composed of parallel circuits the number of which is the same as the number of poles for each phase.

Abstract: An air intake port has an opening part and an air intake port cover forming an air flow channel from the opening part to the air intake port. The air intake port cover has a guide plate to block the opening part and the air intake port from each other and leave an air flow path between the guide plate and an outer perimeter surface facing a vehicle body, a discharge port formed in the outer perimeter surface, a discharge port cover separating the discharge port and the air intake port from each other, and leaving an air flow path from the opening part to the discharge port, and a pair of cylindrical members, one end of each being connected to two holes formed in the discharge port cover, and the other ends facing each other in a travel direction, and tapering in cross-sectional area.

Abstract: A three-phase induction motor includes: a stator having a stator slot having an open slot structure for inserting a formed coil; and a rotor having a rotor slot into which a conductor bar is inserted, the rotor being placed on an inner side of the stator with a clearance between the rotor and the stator. The conductor bar has a polygonal cross-sectional shape having six or more angles, and both end portions of an outer-circumference-side edge surface of the conductor bar are rounded.

Abstract: A three-phase induction motor that is rotationally driven in response to supply of AC power from an inverter including a switching element formed by using a wide bandgap semiconductor includes: a stator including a stator slot having an open slot structure for inserting a former-wound coil; and a rotor including a rotor slot into which a secondary conductor is inserted, the rotor being disposed inside the stator via a gap. Assuming that the number of rotor slots is Nr, the number of stator slots is Ns, and the number of poles is Np, Nr, Ns, and Np are set such that the relationship of Nr?Ns?Np?6 is satisfied.

Abstract: A control device includes a gate-signal generating unit that outputs a gate signal to an inverter circuit and a voltage-vector generating unit that generates a voltage command to the gate-signal generating unit on the basis of a torque command PTR from an upper unit, rotating speed FM of an alternating-current electric motor, and a direct-current voltage value EFC applied to the inverter circuit. The voltage-vector generating unit calculates, on basis of a modulation rate, which is a ratio of the direct-current voltage value EFC and a voltage amplitude command in the voltage command, a PWM current distortion rate serving as an index representing a degree of a current harmonic caused by PWM control, generates the voltage amplitude command value on the basis of the calculated PWM current distortion rate, and outputs the voltage amplitude command value to the gate-signal generating unit.

Abstract: A rotor shaft is configured hollow from an end face on a counter driving side to the front of a proximal end portion of a main plate of a cooling fan. Ventilation holes communicating with a hollow section are provided on a side surface of the rotor shaft. A labyrinth is provided between an end portion on the counter driving side of the main plate and a bracket. According to rotation of the cooling fan, cooling wind enters from the end face, passes through the hollow section, and passes through a ventilation path configured by the main plate and the bearing section via the ventilation holes. The cooling wind is exhausted via an exhaust port provided in the bracket.