CN105827078A - Mixed Excitation Axial Flux Modulation Composite Structure Motor - Google Patents

Abstract

A hybrid excitation axial magnetic flux modulation type composite structure motor relates to the field of hybrid excitation composite motors and aims to solve the problem that an existing hybrid excitation motor is small in output torque. The rotating shaft sequentially penetrates through the permanent magnet outer stator, the first magnet adjusting ring, the inner stator, the second magnet adjusting ring and the electric excitation outer stator, the permanent magnet outer stator, the inner stator and the electric excitation outer stator are rotationally connected with the rotating shaft through bearings, the magnet adjusting ring rotor is fixedly connected with the rotating shaft, and gaps are reserved between the permanent magnet outer stator and the first magnet adjusting ring, between the first magnet adjusting ring and the inner stator, between the inner stator and the second magnet adjusting ring and between the second magnet adjusting ring and the electric excitation outer stator; the permanent magnet is magnetized in a Halbach structure 90-degree magnetizing mode; the first magnetic adjusting ring and the second magnetic adjusting ring are formed by arranging magnetic adjusting iron blocks and epoxy resin non-magnetic-conducting materials at intervals along the circumferential direction. The invention can realize low-speed large-torque output, widens the speed regulation range of the motor and is suitable for electric automobiles.

Description

Mixed Excitation Axial Flux Modulation Composite Structure Motor

technical field

The invention relates to the field of hybrid excitation compound motors.

Background technique

In recent years, due to the development of rare earth permanent magnet materials with high remanence density, high coercive force, and high magnetic energy product, compared with traditional electric excitation motors, permanent magnet motors have small volume and simple structure. It has the advantages of convenient maintenance, high efficiency, high power factor, and high power density in terms of performance. However, because the permanent magnet motor uses a single permanent magnet for excitation, it is difficult to adjust the magnetic field. The traditional electric excitation motor can easily adjust the air gap magnetic field by adjusting the DC or AC excitation current, but its structure is complex, the output torque is small, and the power factor is low.

The main feature of the hybrid excitation motor is that the magnetic field generated by the permanent magnet and the magnetic field generated by the electric excitation winding jointly affect the air gap magnetic field of the motor, and the air gap flux density can be flexibly adjusted by taking advantage of the adjustable excitation current. At the same time, the hybrid excitation motor overcomes the disadvantages of the difficulty in adjusting the magnetic field of the permanent magnet motor and the low power factor of the electric excitation motor, so that the motor has the advantages of small size, compact structure, high power factor, and convenient adjustment of the magnetic field, but there is still the problem of small output torque. .

Contents of the invention

The object of the present invention is to solve the problem of low output torque of the existing hybrid excitation motor, and provide a hybrid excitation axial flux modulation type composite structure motor.

The mixed excitation axial flux modulation composite structure motor of the present invention includes a rotating shaft 1, a permanent magnet outer stator, a magnetic field regulating ring rotor 4, an inner stator, an electric excitation outer stator, a No. 1 bearing 2, a No. 2 bearing 7 and a No. 3 bearing No. bearing 8;

The magnetic adjusting ring rotor 4 includes a No. 1 magnetic adjusting ring and a No. 2 magnetic adjusting ring;

The rotating shaft 1 passes through the permanent magnet outer stator, the No. 1 magnetic adjusting ring, the inner stator, the No. 2 magnetic adjusting ring and the electric excitation outer stator in turn, and the permanent magnetic outer stator is rotationally connected with the rotating shaft 1 through the No. The No. 2 bearing 7 is rotationally connected to the rotating shaft 1, the electric excitation outer stator is rotationally connected to the rotating shaft 1 through the No. 3 bearing 8, and the magnetic adjusting ring rotor 4 is fixedly connected to the rotating shaft 1. Between the permanent magnet outer stator and the No. 1 magnetic adjusting ring, There are gaps between the No. 1 magnetic adjusting ring and the inner stator, between the inner stator and the No. 2 magnetic adjusting ring, and between the No. 2 magnetic adjusting ring and the electric excitation outer stator;

The permanent magnet outer stator includes a coaxial permanent magnet outer stator core 3-1 and a permanent magnet 3-2, and the permanent magnet 3-2 is fixed on the permanent magnet outer stator core 3-1;

The inner stator includes an inner stator core 5-1 and an annular armature winding 5-2, and the annular armature winding 5-2 is wound on the inner stator core 5-1;

The electric excitation outer stator includes an electric excitation outer stator core 6-1 and a DC excitation winding 6-2, and the DC excitation winding 6-2 is wound on the stator teeth of the electric excitation outer stator iron core 6-1; the excitation coil on the adjacent stator teeth The direction of the current is opposite;

Permanent magnet 3-2 is magnetized by Halbach structure 90° magnetization method;

Both the No. 1 magnetic adjustment ring and the No. 2 magnetic adjustment ring are composed of magnetic adjustment blocks 4-1 and epoxy resin non-magnetic conductive materials 4-2 arranged at intervals along the circumferential direction.

Beneficial effects: the mixed excitation axial flux modulation composite structure motor of the present invention combines the characteristics of the disc motor, the flux modulation composite motor and the hybrid excitation motor, adopts the disc structure, and the motor is small in size and easy to install. Using the magnetic gear principle of the magnetic flux modulation composite motor, the air gap magnetic field inside and outside the motor is modulated to obtain low-speed and high-torque output characteristics, which can meet the requirements of direct drive applications such as electric vehicles. The electric excitation outer stator and the permanent magnet outer stator are respectively located on both sides of the inner stator, and the magnetic circuit does not affect each other, avoiding the risk of demagnetization of the permanent magnets, and the permanent magnets are arranged in a Halbach way, and the utilization rate of the permanent magnets is high. The electric excitation winding is wound on the outer stator teeth, which can realize brushless very well. By changing the size and direction of the current on the excitation winding, the size of the air gap magnetic field on the electric excitation side can be flexibly adjusted, thereby widening the speed regulation range of the motor and meeting the requirements of electric vehicles running in a wide speed range, and when the armature winding has a short-circuit fault, By adjusting the excitation current to offset the magnetic field generated by the permanent magnet part, it can achieve high-efficiency demagnetization when the armature winding of the motor is short-circuited.

Description of drawings

Fig. 1 is the structure schematic diagram of hybrid excitation axial flux modulation type composite structure motor according to the present invention;

Fig. 2 is a structural schematic diagram of an electric excitation outer stator core;

Fig. 3 is a schematic structural view of the permanent magnet outer stator;

Fig. 4 is a schematic diagram of permanent magnet arrangement and magnetization direction;

Fig. 5 is a structural schematic diagram of the magnetic ring rotor.

detailed description

Specific embodiment 1: This embodiment is described in conjunction with Fig. 1 to Fig. 5. The hybrid excitation axial flux modulation type composite structure motor described in this embodiment includes a rotating shaft 1, a permanent magnet outer stator, a magnetic field regulating ring rotor 4, and an inner stator , Electric excitation outer stator, No. 1 bearing 2, No. 2 bearing 7 and No. 3 bearing 8;

The magnetic adjusting ring rotor 4 includes a No. 1 magnetic adjusting ring and a No. 2 magnetic adjusting ring;

The rotating shaft 1 passes through the permanent magnet outer stator, the No. 1 magnetic adjusting ring, the inner stator, the No. 2 magnetic adjusting ring and the electric excitation outer stator in turn, and the permanent magnetic outer stator is rotationally connected with the rotating shaft 1 through the No. The No. 2 bearing 7 is rotationally connected to the rotating shaft 1, the electric excitation outer stator is rotationally connected to the rotating shaft 1 through the No. 3 bearing 8, and the magnetic adjusting ring rotor 4 is fixedly connected to the rotating shaft 1. Between the permanent magnet outer stator and the No. 1 magnetic adjusting ring, There are gaps between the No. 1 magnetic adjusting ring and the inner stator, between the inner stator and the No. 2 magnetic adjusting ring, and between the No. 2 magnetic adjusting ring and the electric excitation outer stator;

The permanent magnet outer stator includes a coaxial permanent magnet outer stator core 3-1 and a permanent magnet 3-2, and the permanent magnet 3-2 is fixed on the permanent magnet outer core 3-1;

The inner stator includes an inner stator core 5-1 and an annular armature winding 5-2, and the annular armature winding 5-2 is wound on the inner stator core 5-1;

The electric excitation outer stator includes an electric excitation outer stator core 6-1 and a DC excitation winding 6-2, and the DC excitation winding 6-2 is wound on the stator teeth of the electric excitation outer stator iron core 6-1; the number of stator teeth is 38, Each stator tooth is wound with an excitation coil, 38 excitation coils are connected in series in sequence, and the current direction of the excitation coil on the adjacent stator teeth is opposite, forming a "N-S-N-S-N..." structure;

Permanent magnet 3-2 is magnetized by Halbach structure 90° magnetization method;

Both the No. 1 magnetic adjustment ring and the No. 2 magnetic adjustment ring are composed of magnetic adjustment blocks 4-1 and epoxy resin non-magnetic conductive materials 4-2 arranged at intervals along the circumferential direction.

In this embodiment, the permanent magnet outer stator core 3-1 and the yoke of the electric excitation outer stator core 6-1 of the electric excitation outer stator 6 are directly attached to the motor casing. As shown in Figure 1, in the axial direction, the permanent magnet outer stator and the electric excitation outer stator are symmetrically arranged on both sides of the inner stator. As shown in Figure 4, the permanent magnet 3-2 is formed by a plurality of permanent magnet blocks arranged along the circumferential direction, and every four adjacent permanent magnet blocks form a pair of poles, and the first and third permanent magnets are magnetized in the circumferential direction , and the magnetization direction is opposite, the second and fourth permanent magnets are magnetized in the axial direction, and the magnetization direction is opposite. The two magnetic rings of the rotor 4 are separated from the inner stator by air gaps L2 and L3 respectively, and separated from the permanent magnet outer stator and the electric excitation outer stator by L1 and L4 respectively.

The electric excitation winding 6-2 is wound on the outer stator core of the electric excitation, connected in series in a certain way, and applied a direct current for excitation, so that it follows the right-hand rule, and the excitation direction corresponds to the magnetization direction of the permanent magnet of the permanent magnet part, through Change the size and direction of the current to flexibly adjust the size of the air gap magnetic field on the electric excitation side, thereby widening the speed regulation range of the motor. In addition, when a short-circuit fault occurs in the armature winding, the magnetic field generated by the permanent magnet part is offset by adjusting the excitation current to realize efficient demagnetization when the armature winding short-circuit fault occurs.

Since the magnetic circuits of the permanent magnet part and the electric excitation part of the motor described in this embodiment are independent of each other, adjusting the excitation current will not cause irreversible demagnetization of the permanent magnet, and the motor has high reliability and high electric excitation efficiency.

The magnetic ring rotor 4 adopts the working principle of a new type of magnetic gear transmission. It is applied in the motor and has the characteristics of high torque density, high operating efficiency, non-contact torque transmission and overload self-protection. It can replace mechanical gears in cleaning, Operating in low temperature and high altitude environments, the structure is simpler, and at the same time, the function of low speed and high torque is more prominently reflected.

In this embodiment, the magnetic flux modulation composite motor obtained by integrating the magnetic gear and the permanent magnet synchronous motor has the performance of low-speed and high-torque output. Compared with the radial flux modulation composite motor, the axial flux modulation composite motor Small size, easy installation, greater low-speed output torque.

Specific Embodiment 2: This embodiment is a further limitation of the mixed excitation axial flux modulation composite structure motor described in Embodiment 1. In this embodiment, the inner stator core 5-1 is provided with slots along the circumferential direction. The annular armature winding 5-2 is embedded in the slot.

Specific Embodiment 3: This embodiment is a further limitation of the mixed excitation axial flux modulation composite structure motor described in Embodiment 1. In this embodiment, the number of pole pairs of the inner stator is P ₁ , and the permanent magnet outer stator The number of pole pairs and the number of pole pairs of the electric excitation external stator are both P ₂ , and the number of adjusting magnet blocks 4 - 1 in the magnetic adjusting ring rotor 4 is Ns, P ₁ +P ₂ =Ns.

The air-gap harmonic magnetic field obtained by applying voltage to the annular armature winding 5-2 of the inner stator, and the permanent magnet 3-2 on the permanent magnet outer stator and the DC field winding 6-2 on the electric excitation outer stator The air gap harmonic magnetic field is analyzed and analyzed, and the relationship between the number of pole pairs P ₁ of the ring armature winding 5-2 of the inner stator in the compound motor, the number of pole pairs of the outer stator P ₂ and the number Ns of magnetic modulation blocks is obtained as follows: P ₁ =|mP ₂ +kNs|, among them, m=1, 3, 5,..., +∞; k=0, ±1, ±2,..., ±∞; when m=1, k=-1 , the harmonic magnetic field modulated by the magnetic ring is the strongest, and the harmonic magnetic field that mainly transmits torque on both sides of the magnetic ring has the same electrical angular velocity, and the speed ratio and transmission ratio of this compound motor can be obtained Gr=mP ₂ + kNs/mP ₂ , in this way, the number of outer stator pole pairs and the ratio of the magnetic ring can be selected to meet the demand for stable torque, otherwise the torque will not be transmitted smoothly, as shown in Figure 2, Figure 3 and Figure 5. The number of pole pairs of the ring armature winding of the inner stator is P ₁ =3, and the number of magnetic adjustment blocks Ns is 25, so that the number of pole pairs of the outer stator is P ₂ =22, and the speed regulation ratio is 25/3.

Claims (3)

1. composite excitation axial magnetic flux modulation system composite structure motor, it is characterized in that, described motor includes rotating shaft (1), permanent magnetism external stator, adjustable magnetic rotor (4), inner stator, electrical excitation external stator, a bearing (2), No. two bearings (7) and No. three bearings (8)；

Described adjustable magnetic rotor (4) includes an adjustable magnetic ring and No. two adjustable magnetic rings；

Described rotating shaft (1) sequentially passes through permanent magnetism external stator, a number adjustable magnetic ring, inner stator, No. two adjustable magnetic rings and electrical excitation external stator, and permanent magnetism external stator is rotationally connected with rotating shaft (1) by a bearing (2), inner stator is rotationally connected with rotating shaft (1) by No. two bearings (7), electrical excitation external stator is rotationally connected with rotating shaft (1) by No. three bearings (8), adjustable magnetic rotor (4) is fixing with rotating shaft (1) to be connected, between permanent magnetism external stator and an adjustable magnetic ring, between a number adjustable magnetic ring and inner stator, between inner stator and No. two adjustable magnetic rings, and all leave gap between No. two adjustable magnetic rings and electrical excitation external stator；

Described permanent magnetism external stator includes permanent magnetism external stator (3-1) and the permanent magnet (3-2) unshakable in one's determination being coaxially disposed, and permanent magnet (3-2) is fixed on iron core (3-1)；

Inner stator includes internal stator iron core (5-1) and annular armature winding (5-2), and annular armature winding (5-2) is wrapped on internal stator iron core (5-1)；

Electrical excitation external stator (6) includes electrical excitation external stator (6-1) and DC excitation winding (6-2) unshakable in one's determination, and DC excitation winding (6-2) is wrapped on the stator tooth of electrical excitation external stator (6-1) unshakable in one's determination；

Permanent magnet (3-2) uses 90 ° of modes of magnetizing of Halbach structure to magnetize；

A number adjustable magnetic ring and No. two adjustable magnetic rings are by adjustable magnetic iron block (4-1) and epoxy resin non-magnet material (4-2) is circumferentially spaced rearranges.

Composite excitation axial magnetic flux modulation system composite structure motor the most according to claim 1, it is characterised in that internal stator iron core (5-1) is outside along the circumferential direction has groove, and annular armature winding (5-2) is embedded in groove.

Composite excitation axial magnetic flux modulation system composite structure motor the most according to claim 1 and 2, it is characterised in that the number of pole-pairs of inner stator is P₁, the number of pole-pairs of permanent magnetism external stator is P with the number of pole-pairs of electrical excitation external stator₂, in adjustable magnetic rotor (4), the quantity of adjustable magnetic iron block (4-1) is Ns, P₁+P₂=Ns.