CN-114123576-B - Permanent magnet motor

CN114123576BCN 114123576 BCN114123576 BCN 114123576BCN-114123576-B

Abstract

The invention provides a permanent magnet motor. Which can improve the output per unit volume. A permanent magnet motor (1) is provided with a pair of first permanent magnets (5) and a second permanent magnet (6) located between the pair of first permanent magnets (5) for each magnetic pole inside a rotor (2). A first gap (7) is provided at the radially outer end of each first permanent magnet (5), a second gap (8) is provided at the both ends of each second permanent magnet (6), a first magnetic circuit (9) communicating with the teeth (3) of the stator (4) is divided between each adjacent first gap (7), and a second magnetic circuit (10) is divided between each adjacent first gap (7) and second gap (8). When the opening angles of the first and second magnetic circuits (9, 10) centering on the rotation axis (A) are set to alpha and beta and the opening angle of the magnetic circuit passing through the tooth is set to gamma, an outer peripheral hole (12) is provided so as to satisfy the relation alpha < beta and the opening angle beta is close to the opening angle gamma.

Inventors

Datong-Xi'an expensive

Assignees

日立安斯泰莫株式会社

Dates

Publication Date: 20260505
Application Date: 20210716
Priority Date: 20200727

Claims (3)

1. A permanent magnet motor comprising a rotor and a stator, wherein a plurality of teeth are provided on the stator and facing inward, the plurality of teeth are opposed to a plurality of positions on the outer periphery of the rotor to form a rotating magnetic field, In the rotor, a pair of first permanent magnets and second permanent magnets are provided for each magnetic pole of the rotor, wherein the pair of first permanent magnets are arranged in a V-shape or U-shape that opens to the outside in the radial direction of the rotor, the second permanent magnets are arranged along the outer periphery of the rotor between the ends of the outside in the radial direction of the pair of first permanent magnets in the circumferential direction of the rotor, A first gap is provided at an end portion of each of the first permanent magnets on the radially outer side of the rotor, a second gap is provided at both end portions of each of the second permanent magnets, A first magnetic circuit communicating with the teeth is divided between each adjacent first space, a second magnetic circuit communicating with the teeth is divided between each adjacent first space and second space, The permanent magnet motor is characterized in that, Setting an opening angle at an outer peripheral portion of the rotor of the first magnetic circuit with respect to the rotation axis to be α, setting an opening angle at an outer peripheral portion of the rotor of the second magnetic circuit with respect to the rotation axis to be β, setting a virtual line connecting a side of the magnetic circuit passing through the tooth portion closest to the first permanent magnet in the circumferential direction with respect to the rotation center at a shortest distance to be γ1, setting a virtual line connecting a side of the magnetic circuit passing through the tooth portion closest to the second permanent magnet in the circumferential direction with respect to the rotation center at a shortest distance to be γ2, and setting opening angles of the virtual line γ1 and the virtual line γ2 with respect to the rotation axis to be γ, An outer peripheral hole portion is provided between the first void portion and the virtual line γ1 in the circumferential direction so as to satisfy a relation of α < β and the open angle β is close to the open angle γ, and the second void portion extends to meet the virtual line γ2.
2. A permanent magnet motor according to claim 1, wherein, As a configuration when viewed in a cross section perpendicular to the rotation axis of the rotor, the outer peripheral hole portion has a shape elongated in the radial direction of the rotor, and the elongated portion is provided so as to extend along the second magnetic path in contact with the virtual line γ1.
3. A permanent magnet motor according to claim 1 or 2, wherein, When the magnetic circuit of one tooth portion and one of the second magnetic circuits on both sides of each of the second permanent magnets are substantially integrated, the magnetic circuit of the other tooth portion and the other second magnetic circuit on the other side are substantially integrated.

Description

Permanent magnet motor Technical Field The present invention relates to permanent magnet motors. Background Conventionally, there is known a permanent magnet motor including a rotor and a stator, wherein the stator is provided with inward teeth that face the outer periphery of the rotor to form a rotating magnetic field (for example, see patent documents 1 and 2). In the permanent magnet motor of patent document 1, a pair of first permanent magnets and second permanent magnets are provided for each magnetic pole in the rotor, wherein the pair of first permanent magnets are arranged in a V-shape that flares radially outward, and the second permanent magnets are arranged along the outer periphery of the rotor between radially outer ends of the first permanent magnets. The radially outer end portions of the respective first permanent magnets are provided with first void portions, and the both end portions of the respective second permanent magnets are provided with second void portions. The first and second gaps divide the first and second magnetic circuits, respectively, the first magnetic circuit communicates with each tooth between each adjacent first gap, and the second magnetic circuit communicates with each tooth between each adjacent first and second gap. Further, by setting the width w1 of the first magnetic circuit to a width equal to or larger than the width w2 of the second magnetic circuit (w 1. Gtoreq.w2), the reluctance torque (reluctance torque) can be increased, and as a result, high torque and high rotation driving can be realized. On the other hand, in the permanent magnet motor of patent document 2, a magnetic flux blocking portion that blocks a closed-loop magnetic flux generated around the armature winding is provided in the circumferential direction of the outer peripheral portion of the rotor. The magnetic flux blocking portion has a plurality of nonmagnetic portions extending in the radial direction between permanent magnets adjacent to the outer periphery of the rotor. The plurality of nonmagnetic portions are arranged so as to expand from the outer peripheral side to the inner peripheral side of the rotor and so as to become shorter in length from the d-axis toward the q-axis. Prior art literature Patent literature Patent document 1 Japanese patent application laid-open No. 2011-229395 Patent document 2 Japanese patent No. 6002217 Disclosure of Invention Problems to be solved by the invention However, in the permanent magnet motor of patent document 1, torque is generated by magnetic lines of force passing through the first magnetic circuit and the second magnetic circuit and entering the teeth, but the relationship between the first magnetic circuit, the second magnetic circuit and the teeth is not disclosed at all. Therefore, it is considered that there is room for improvement in torque (output per unit volume) in relation to the first magnetic circuit, the second magnetic circuit, and the tooth portion. In the permanent magnet motor of patent document 2, the magnetic paths between the adjacent permanent magnets are narrowed by the presence of the plurality of nonmagnetic parts, and magnetic saturation occurs in the rotor core, so that the loss caused by this is not low. Therefore, there is room for improvement for increasing the torque of the permanent magnet motor. The present invention has been made in view of the above problems occurring in the prior art, and an object of the present invention is to improve the output per unit volume of a permanent magnet motor. Means for solving the problems The permanent magnet motor of the present invention comprises a rotor and a stator, wherein a plurality of inward teeth are arranged on the stator, the teeth are opposite to a plurality of positions of the outer periphery of the rotor for forming a rotating magnetic field, In the rotor, a pair of first permanent magnets and second permanent magnets are provided for each magnetic pole of the rotor, wherein the pair of first permanent magnets are arranged in a V-shape or U-shape that opens to the outside in the radial direction of the rotor, the second permanent magnets are arranged along the outer periphery of the rotor between the ends of the outside in the radial direction of the pair of first permanent magnets in the circumferential direction of the rotor, A first gap is provided at an end portion of each of the first permanent magnets on the radially outer side of the rotor, a second gap is provided at both end portions of each of the second permanent magnets, A first magnetic circuit communicating with the teeth is divided between each adjacent first space, a second magnetic circuit communicating with the teeth is divided between each adjacent first space and second space, The permanent magnet motor is characterized in that, Setting an opening angle at an outer peripheral portion of the rotor of the first magnetic circuit with respect to the rotation axis to be α, setting an opening ang