Main motor for railway vehicle

• US 10,367,388 B2
• Filed: 09/30/2011
• Issued: 07/30/2019
• Est. Priority Date: 09/30/2011
• Status: Active Grant

• Current Assignee: Mitsubishi Electric Corporation
• Original Assignee: Mitsubishi Electric Corporation
• Inventors: Kaneko, Kenta, Kometani, Haruyuki
• Primary Examiner(s): Leung, Quyen P
• Assistant Examiner(s): Chang, Minki
• Application Number:
  US14/346,239
• Publication Number:
  US 20140319952A1
• Time in Patent Office: 2,860 Days
• Field of Search: 310159, 310161, 310179, 310195, 310198
• CPC Class Codes: H02K 2203/09 Machines characterised by wiring elements other than wires, e.g. bus rings, for connecting the winding terminations
• CPC Class Codes: H02K 3/12 arranged in slots
• CPC Class Codes: H02K 3/28 Layout of windings or of connections between windings windings for pole-changing H02K17/06, H02K17/14, H02K19/12, H02K19/32
• CPC Class Codes: H02K 3/38 around winding heads, equalising connectors, or connections thereto
• CPC Class Codes: H02P 25/22 Multiple windings; Windings for more than three phases
• CPC Class Codes: Y02T 10/64 Electric machine technologies in electromobility

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.

Claims

1. A three-phase AC main motor for a railway vehicle that is mounted on an electric vehicle and is used for driving the electric vehicle, is rotationally driven upon receiving an AC power supplied from an inverter circuit that includes a switching element, and is driven by having a voltage having a PWM waveform applied from the inverter circuit in at least part of a speed range of the electric vehicle, the main motor comprising:

a stator that is configured to include an annular stator core provided with a plurality of slots in a circumferential direction and a stator winding that includes U-phase coils, V-phase coils, and W-phase coils that are wound on the stator core and are accommodated in the slots, and that is three-phase star-connected and is composed of parallel circuits, a number of which is the same as the number of poles for each phase, wherein the number of poles is an even number equal to or greater than four and the number of parallel circuits is an even number equal to or greater than four, each of the U-phase coils, the V-phase coils configuring the parallel circuits of a corresponding phase;

a rotor that is arranged on an inner side of the stator core;

a first circuit ring that is provided to the stator core along the circumferential direction, that has a substantially C shape, and that is a plate-like metal member including a plurality of insulating coating portions and a plurality of uninsulated wire connection portions provided at positions corresponding to the U-phase coils, the parallel circuits configured from the U-phase coils being connected to the uninsulated wire connection portions;

a second circuit ring that is provided to the stator core along the circumferential direction, that has a substantially C shape, and that is a plate-like metal member including a plurality of insulating coating portions and a plurality of uninsulated wire connection portions provided at positions corresponding to the V-phase coils, the parallel circuits configured from the V-phase coils being connected to the uninsulated wire connection portions;

a third circuit ring that is provided to the stator core along the circumferential direction, that has a substantially C shape, and that is a plate-like metal member including a plurality of insulating coating portions and a plurality of uninsulated wire connection portions provided at positions corresponding to the W-phase coils, the parallel circuits configured from the W-phase coils being connected to the uninsulated wire connection portions; and

a fourth circuit ring that is provided to the stator core along the circumferential direction, that has a substantially C shape, that is a plate-like metal member including a plurality of insulating coating portions and a plurality of uninsulated wire connection portions provided at positions corresponding to the U-phase coils, the V-phase coils, and the W-phase coils, and that is used for a neutral-point connection of the stator winding, the parallel circuits configured from the U-phase coils, the parallel circuits configured from the V-phase coils, and the parallel circuits configured from the W-phase coils being connected to the uninsulated wire connection portions,

wherein the first circuit ring, the second circuit ring, and the third circuit ring are coaxial to each other,

wherein one end portion of an inner circuit ring among the first circuit ring, the second circuit ring, and the third circuit ring protrudes beyond an exterior circuit ring among the first circuit ring, the second circuit ring, and the third circuit ring through a gap between opposing end portions of the exterior circuit ring,

wherein the one end portion of the inner circuit ring is directly connected to a lead wire,

wherein the first circuit ring, the second circuit ring, the third circuit ring, and the fourth circuit ring are successively arranged in a radially inward direction of the stator core, starting with the first circuit ring and followed by the second circuit ring, the third circuit ring, and then the fourth circuit ring,

wherein one end portion of the second circuit ring to which a lead wire is directly connected is located between one end portion of the first circuit ring to which a lead wire is directly connected and one end portion of the third circuit ring to which a lead wire is directly connected, each of the end portions of the second circuit ring, the first circuit ring, and the third circuit ring extend circumferentially, and

wherein the insulating coating portions of each of the first to fourth circuit rings are separated from the insulating coating portions of each of the other circuit rings among the first to fourth circuit rings.

2. The main motor for a railway vehicle according to claim 1, wherein the number of poles is four or six.

3. The main motor for a railway vehicle according to claim 1, wherein the switching element is formed by using a wide bandgap semiconductor.

4. The main motor for a railway vehicle according to claim 1, wherein each coil is located completely within one slot.

5. The main motor for a railway vehicle according to claim 1, wherein the stator winding has a four-pole, four-parallel-circuit configuration.

6. The main motor for a railway vehicle according to claim 1, wherein the stator winding has a six-pole, six-parallel-circuit configuration.

7. The main motor for a railway vehicle according to claim 1, wherein in each of the phases, the coils of the poles adjacent to each other in the circumferential direction are wound in opposite directions to each other.

8. The main motor for a railway vehicle according to claim 1, wherein in each of the phases, the coils of the parallel circuits in any one of the poles are arranged in reverse order to the coils of the parallel circuits in the pole adjacent to the any one of the poles in the circumferential direction.