Solid magnetic pole salient pole synchronous motor rotor

Abstract

The invention discloses a solid magnetic pole salient pole synchronous motor rotor, belongs to the technical field of motors, and aims to solve the problem that the running efficiency of a motor is affected due to large eddy current of an existing solid magnetic pole synchronous motor. The rotor comprises a rotor core, a magnet exciting coil and damping cage units, one damping cage unit is arranged below each magnetic pole, and each damping cage unit is composed of a plurality of damping bars and damping rings at the two ends; 2P rotor teeth are uniformly distributed along the circumferential direction of the rotor core, P is the number of pole pairs, and an annular excitation coil is wound on each rotor tooth; the pole shoes of the rotor teeth are provided with 2M + 1 damping grooves along the outer arc surfaces, the damping grooves are axial semi-closed round bottom grooves, and the central damping groove is arranged at the central axis of the rotor magnetic pole; the N damping grooves are symmetrically formed in the two sides of the pole body of the rotor tooth, grooving treatment is carried out, the damping grooves are arranged to be semi-closed grooves, the damping strips are placed in the damping grooves, and grooving on the surface of the rotor and placing of the damping strips are combined, so that eddy current loss is reduced.

Description

Technical Field

[0001] The invention relates to a solid magnetic pole salient pole synchronous motor rotor, belonging to the technical field of motors. Background Art

[0002] Solid pole synchronous motors have the characteristics of low manufacturing cost and high material strength in terms of process. Compared with laminated pole synchronous motors, it has higher mechanical reliability and better power index. For large motors, it is relatively difficult to manufacture laminated poles, which makes solid poles have certain advantages in process. However, solid poles themselves also have disadvantages that cannot be ignored. They will be affected by magnetic field harmonics, thus generating large eddy currents in the poles. Due to the skin effect, eddy currents will be concentrated at a certain penetration depth, which has a great impact on the performance indicators of solid pole motors. The eddy current effect is caused by the formation of circular currents in the conductor by the current in the magnetic field. In salient pole motors, when the rotor rotates, the magnetic field on its surface will change, thereby generating eddy currents inside the rotor. These eddy currents will not only cause energy loss, but also generate heat in the motor, thereby affecting the performance and life of the motor. In particular, large solid pole motors, affected by the motor structure, have very large harmonic components in their motor magnetic field. The large eddy currents will generate huge eddy current losses, seriously reducing the operating efficiency of the motor. Summary of the invention

[0003] In view of the problem that the existing solid pole synchronous motor has large eddy current and affects the motor operation efficiency, the present invention provides a solid pole salient pole synchronous motor rotor.

[0004] The solid pole salient pole synchronous motor rotor of the present invention comprises a rotor core 11, an excitation coil 12 and a damping cage unit, wherein a damping cage unit is arranged under each magnetic pole, and the damping cage unit is composed of a plurality of damping bars 14 and damping rings 13 at both ends;

[0005] The rotor core 11 has 2P rotor teeth evenly distributed along the circumferential direction, where P is the number of pole pairs, and an annular excitation coil 12 is wound around each rotor tooth;

[0006] The pole shoe 33 of the rotor tooth is provided with 2M+1 damping grooves 31 along the outer arc surface, the damping groove 31 is an axial semi-closed round bottom groove, and the central damping groove 31 is arranged at the central axis of the rotor magnetic pole;

[0007] N damping grooves 31 are symmetrically provided on both sides of the pole body 32 of the rotor tooth;

[0008] A damping bar 14 passes through each damping slot 31 , and both ends of the damping bar 14 under each rotor pole are connected to two damping rings 13 .

[0009] Preferably, all damping grooves 31 have the same size.

[0010] Preferably, the pitches between the damping grooves at the pole shoe 33 on the same rotor magnetic pole are equal, and the pitches between the damping grooves on each side of the pole body 32 are equal.

[0011] Preferably, the damping ring 13 is a strip structure arranged along the edge of the rotor teeth, and a plurality of mounting holes are arranged on the damping ring 13 , and the mounting holes match the damping grooves 31 .

[0012] Preferably, the damping rings 13 at both ends of the same rotor pole are electrically connected to all the damping bars 14 , and a plurality of damping bars 14 are connected in parallel; the damping rings 13 under different rotor poles are not connected.

[0013] Beneficial effects of the present invention: The present invention provides a novel solid-pole salient-pole synchronous motor rotor, wherein a damping groove is arranged at the pole body of the solid-pole synchronous motor rotor, and a groove treatment is performed to set it as a semi-closed groove, and a damping strip is placed in the damping groove, and the groove of the rotor surface is combined with the placement of the damping strip. Slotting the rotor surface will change the distribution of the magnetic field on the rotor surface, so that the magnetic field is more concentrated near the slot, thereby reducing the magnetic field intensity at the bottom of the slot. This change in the magnetic field distribution helps to reduce eddy current losses, because eddy currents mainly occur in areas with large magnetic field changes. Slotting can also increase the heat dissipation area of ​​the rotor surface, improve the heat dissipation capacity, and help reduce the temperature of the motor, thereby reducing the increase in eddy current losses caused by temperature rise. The damping winding is used as a starting winding in the synchronous motor, and can suppress the vibration and noise generated by the rotor during rotation, and can also have a certain effect on the eddy current loss. The damping strip can absorb and disperse the eddy current in the rotor through its conductive property, thereby reducing the eddy current loss. In addition, the damping winding can also improve the dynamic performance of the motor and improve the stability and reliability of the motor. Combining rotor surface grooving with the placement of damping strips can further reduce eddy current losses and improve motor operating efficiency while improving motor stability. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 The three-dimensional model of the rotor of the solid magnetic pole salient pole synchronous motor of the present invention;

[0015] Figure 2 The solid magnetic pole salient pole synchronous motor rotor core structure model of the present invention;

[0016] Figure 3 It is a two-dimensional model of the rotor core and damping holes of the solid magnetic pole salient pole synchronous motor of the present invention;

[0017] Figure 4 is a schematic diagram of the damping slot structure;

[0018] Figure 5 It is a schematic diagram of the structure of a single magnetic pole damping winding of a solid magnetic pole salient pole synchronous motor of the present invention;

[0019] Figure 6 The magnetic flux line distribution of the undamped rotor of the solid-pole salient-pole synchronous motor of the present invention;

[0020] Figure 7 The magnetic flux line distribution of the semi-damped rotor of the solid-pole salient-pole synchronous motor of the present invention;

[0021] Figure 8 The magnetic flux line distribution of the fully damped rotor of the solid pole salient pole synchronous motor of the present invention;

[0022] The reference numerals in the accompanying drawings represent: 11: rotor core, 12: excitation coil, 13: damping ring, 14: damping bar, 31: damping groove, 32: pole body, 33: pole shoe. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments may be combined with each other.

[0025] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments, but they are not intended to limit the present invention.

[0026] Specific implementation method 1: The following is combined Figures 1 to 8 The present embodiment is described. The solid pole salient pole synchronous motor rotor described in the present embodiment comprises a rotor core 11, an excitation coil 12 and a damping cage unit. A damping cage unit is arranged under each magnetic pole. The damping cage unit is composed of a plurality of damping bars 14 and damping rings 13 at both ends.

[0027] The rotor core 11 has 2P rotor teeth evenly distributed along the circumferential direction, where P is the number of pole pairs, and an annular excitation coil 12 is wound around each rotor tooth;

[0028] The pole shoe 33 of the rotor tooth is provided with 2M+1 damping grooves 31 along the outer arc surface, the damping groove 31 is an axial semi-closed round bottom groove, and the central damping groove 31 is arranged at the central axis of the rotor magnetic pole;

[0029] N damping grooves 31 are symmetrically provided on both sides of the pole body 32 of the rotor tooth;

[0030] A damping bar 14 passes through each damping slot 31 , and both ends of the damping bar 14 under each rotor pole are connected to two damping rings 13 .

[0031] All damping grooves 31 have the same size.

[0032] Example 1

[0033] like Figure 1 Each pole excitation coil 12 is formed by winding a plurality of turns of stranded wires in series, which are respectively wound around each magnetic pole of the rotor core 11 and are supplied with corresponding excitation current.

[0034] Example 2

[0035] like Figure 3 and Figure 4 The damping slots 31 on the rotor core 11 are round bottom slots, each of which is slotted on the surface of the rotor core 11 and has a semi-closed structure, and the distribution circle radius of all damping slots 31 is equal. Slotting the rotor surface will change the distribution of the magnetic field on the rotor surface, so that the magnetic field is more concentrated near the slot, thereby reducing the magnetic field strength at the bottom of the slot. This change in magnetic field distribution helps to reduce eddy current losses.

[0036] Example 3

[0037] Combination Figure 3 It can be seen that one damping groove 31 is set at the central axis of the magnetic pole in the pole shoe 33, and the other damping grooves 31 are set on both sides and symmetrically with the axis, and the pitch between the damping grooves 31 is the same. The setting method at the pole body 32: the damping grooves 31 are set along both sides of the pole body 32 of the magnetic pole and are symmetrically distributed with the central axis. At the same time, the pitch between the damping grooves at the pole shoe 33 on the same rotor pole is equal, and the pitch between the damping grooves on each side of the pole body 32 is equal. So far, the distribution of each magnetic pole damping groove 31 is set along the eddy current effect on the surface of the salient pole motor rotor.

[0038] Example 4

[0039] Combination Figure 5 It can be seen that the same number of damping bars 14 are arranged on each rotor pole, and the damping bars 14 pass through the rotor core 11 axially. All damping bars 14 have the same size and a length slightly longer than the axial length of the rotor core 11, and are connected to each pole damping ring 13 to form a damping cage structure. The damping bars 14 can be used as damping windings through their conductive properties to further absorb and disperse the eddy currents in the rotor. The damping winding is set in synchronous motors and phase regulators. The damping winding is used as a starting winding. At the same time, the current in the damping winding will generate electromagnetic force, which will offset the vibration and noise generated by the interaction between the magnetic field and the rotor of the motor. The damping winding can also increase the stability of the motor, accelerate the decelerating rotor through the generated magnetic field, decelerate the accelerating rotor, and suppress excessive transient changes in power or torque.

[0040] Example 5

[0041] Combination Figure 5 It can be seen that each magnetic pole damping strip 42 is connected with a damping ring 41, so that the damping strip of each magnetic pole is electrically in parallel, and the damping rings between the poles are not connected but are set separately.

[0042] Example 6

[0043] Combination Figure 5 It can be seen that the damping ring 13 is a strip structure arranged along the edge of the rotor teeth, and the damping ring 13 is provided with mounting holes for mounting the damping strip 14, and the position of the mounting hole is adapted to the damping groove 31 on the rotor core 11. The size of the damping ring 13 is adapted to the rotor core magnetic pole 11, which is convenient for the installation of the excitation winding and the operation of the motor. The specific installation of the damping ring 13 can be determined according to the actual situation of the motor.

[0044] Example 7

[0045] According to the solid magnetic pole salient pole synchronous motor rotor structure provided by the present invention, finite element simulations are performed on three different structures of solid magnetic pole salient pole synchronous motors. The simulation results of eddy current effect at the rotor core are shown in Figure 2. Figure 6 , Figure 7 , Figure 8 As shown in the figure, when the solid pole motor without damping structure is used, the magnetic lines of force on the rotor surface are dense and the eddy current effect on the rotor surface is more obvious. When the semi-damped solid pole motor rotor is used, the density of magnetic lines of force at the pole shoe is reduced, which has a certain inhibitory effect on the eddy current effect. When the solid pole salient pole synchronous motor adopts a new rotor structure, that is, slots are opened at the pole body and damping strips are placed, the density of magnetic lines of force at the rotor pole is greatly reduced, and the inhibitory effect on the eddy current effect is more significant.

[0046] Although the present invention is described herein with reference to specific embodiments, it should be understood that these embodiments are merely examples of the principles and applications of the present invention. It should therefore be understood that many modifications may be made to the exemplary embodiments and that other arrangements may be devised without departing from the spirit and scope of the present invention as defined by the appended claims. It should be understood that the various dependent claims and features described herein may be combined in a manner different from that described in the original claims. It should also be understood that the features described in conjunction with a single embodiment may be used in other described embodiments.

Claims

1. A solid pole salient pole synchronous motor rotor, characterized in that: It comprises a rotor core (11), an excitation coil (12) and a damping cage unit, wherein a damping cage unit is arranged under each magnetic pole, and the damping cage unit is composed of a plurality of damping bars (14) and damping rings (13) at both ends; The rotor core (11) has 2P rotor teeth evenly distributed along the circumferential direction, where P is the number of pole pairs, and an annular excitation coil (12) is wound around each rotor tooth; The pole shoe (33) of the rotor tooth is provided with 2M+1 damping grooves (31) along the outer arc surface, the damping groove (31) is an axial semi-closed circular bottom groove, and the central damping groove (31) is arranged at the center axis of the rotor magnetic pole; N damping grooves (31) are symmetrically provided on both sides of the pole body (32) of the rotor tooth; A damping bar (14) passes through each damping groove (31), and both ends of the damping bar (14) under each rotor magnetic pole are connected to two damping rings (13).

2. A solid-pole salient-pole synchronous motor rotor according to claim 1, characterized in that: All damping grooves (31) have the same size.

3. A solid-pole salient-pole synchronous motor rotor according to claim 2, characterized in that: The pitches between the damping grooves at the pole shoe (33) on the same rotor magnetic pole are equal, and the pitches between the damping grooves on each side of the pole body (32) are equal.

4. The solid-pole salient-pole synchronous motor rotor according to claim 1, characterized in that: The damping ring (13) is a strip-shaped structure arranged along the edge of the rotor teeth. A plurality of mounting holes are arranged on the damping ring (13), and the mounting holes match the damping grooves (31).

5. A solid-pole salient-pole synchronous motor rotor according to claim 4, characterized in that: The damping rings (13) at both ends of the same rotor magnetic pole are electrically connected to all the damping strips (14), and a plurality of damping strips (14) are connected in parallel; the damping rings (13) under different rotor magnetic poles are not connected.

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