Structure of novel three-stator axial-radial hybrid magnetic flux motor

Abstract

At present, the development of a radial magnetic circuit permanent magnet motor is very mature, and related research results are numerous. At present, an axial magnetic circuit permanent magnet motor gradually attracts wide attention of the academic circle. The axial magnetic circuit motor has the advantages of being compact in structure, high in torque density, excellent in heat dissipation performance and the like, and the performance requirement of a direct-drive propulsion system is fully met. A three-stator structure is adopted, the main magnetic flux is formed by connecting the radial magnetic flux and the axial magnetic flux in parallel, the radial-axial magnetism gathering effect is achieved through the radial-axial magnetic circuit, the winding turn linkage magnetic flux is effectively improved, and then the torque output capacity of the motor is improved. Based on the particularity of the magnetic circuit of the radial-axial three-dimensional hybrid magnetic circuit permanent magnet motor, the axial stator winding and the radial stator winding respectively adopt an annular winding and a drum-shaped winding. The ring winding configuration eliminates ineffective end portions of conventional radial / axial motor windings and achieves winding loss suppression. In the drum-shaped windings distributed in the circumferential direction of the stator, the drum-shaped windings can effectively eliminate the influence of the stator yoke.

Description

Technical Field

[0001] This invention relates to the field of novel motor design and manufacturing, specifically to the structure of a novel three-stator axial-radial hybrid flux motor. Background Technology

[0002] Based on the direction of the air gap magnetic flux, common permanent magnet motors can be divided into two main categories: radial flux permanent magnet motors and axial flux permanent magnet motors. Existing radial flux permanent magnet motors have lower magnetic flux density near the shaft, resulting in insufficient utilization of radial space. Axial flux permanent magnet motors have a shorter stator inner circumference than outer circumference, requiring sufficient space for winding. Through special structural design, radial and axial flux are combined to form a hybrid radial-axial flux permanent magnet motor. This retains the advantages of high torque density and compact structure of axial flux permanent magnet motors while improving the utilization of internal space by incorporating a radial rotor. Currently, there are some research results in the field of hybrid radial-axial flux permanent magnet motors, but compared to traditional radial and axial flux permanent magnet motors, their design theory, analysis methods, and optimization strategies still require further in-depth research and improvement. For example, the design principles of axial and radial magnetic circuits are not yet clear; the analysis of hybrid axial and radial magnetic circuits relies on three-dimensional finite element simulation, resulting in a huge computational load and long processing time; what special requirements do hybrid magnetic circuits have on material properties; how do different core materials affect motor performance; and how can different performance indicators be considered during motor optimization? In view of this, this invention conducts an in-depth analysis of traditional radial and axial flux permanent magnet motors and proposes a modular multi-stator hybrid axial and radial flux permanent magnet motor. It incorporates a radial inner rotor within the traditional axial flux permanent magnet motor, creating a three-stator structure that enables a hybrid axial and radial magnetic circuit, thereby improving the motor's torque density. This invention focuses on the topology, design, analysis, and optimization strategies of hybrid axial and radial flux permanent magnet motors, promoting technological advancements and laying a practical foundation. Therefore, this invention has significant theoretical value and practical prospects. Summary of the Invention

[0003] 1. The composite inner and outer rotor structure is equipped with axial magnets and radial magnets respectively, providing a multi-magnetic-chain structure.

[0004] 2. The composite inner and outer rotor structure is assembled as a single unit using an interference fit. One side is positioned by a shaft shoulder, while the other side is reinforced with a rolled edge to reduce magnetic flux loss.

[0005] 3. The outer rotor section uses stacked silicon steel sheets to reduce eddy current losses, while the inner rotor is equipped with axial magnets to maximize magnetic flux utilization. The outer rotor is made of 0.27mm thick silicon steel sheets, resulting in lower stator core losses.

[0006] 4. The stator adopts a triple stator configuration, consisting of an axial double stator and a radial stator.

[0007] 5. The stator radial winding uses a toroidal coil, utilizing the axial space of the motor. The stator axial winding uses a drum-shaped coil, utilizing the radial space of the motor. Detailed Implementation

[0008] like Figure 1 The figure shows an overall diagram of a novel three-stator axial-radial hybrid flux motor. In the figure, 1 is the left end cover, 2 is the left axial stator, 3 is the radial stator, 4 is the right end cover, 5 is the outer rotor, 6 is the right axial stator, 7 is the inner rotor, and 8 is the shaft with internal splines.

[0009] Both the left and right end caps are made of non-magnetic 0Cr18Ni10Ti material, effectively reducing magnetic leakage. The end caps are bolted to the stator disc. The axial left stator is as follows... Figure 2 As shown, it is made of rolled silicon steel sheets, and will be as follows Figure 3 As shown, silicon steel sheets are laminated to reduce eddy current losses. A T-shaped iron core is used to wind the stator windings, which are fan-shaped with radial lead-out connections at the ends, thus not occupying axial space. Therefore, a T-shaped stator core combined with a disc-type inner rotor forms an axial hybrid magnetic circuit, improving the motor's space utilization. The inner and outer ends of the fan-shaped windings are connected circumferentially, and the winding coils are distributed around the stator teeth, while the inner and outer ends of the annular windings are connected axially. Considering the characteristic of the fractional slot concentrated windings being arranged in a layered manner on the left and right sides, resulting in a smaller actual pitch, the effects of concentration and layering on the harmonic magnetomotive force are analyzed, and the influence of concentration and layering on the stator magnetomotive force is verified through finite element simulation.

[0010] Axial stator core such as Figure 4 As shown, it is made of 0.27mm silicon steel sheet, with a toroidal winding coil wound in its slots, as shown in the figure. Figure 5 As shown, the two windings are connected in series to generate axial magnetic flux. The toroidal winding has a shorter end, which can reduce the copper loss of the motor to a certain extent. A yokeless modular stator can be used, simplifying the stator processing and assembly. Combined with a fractional slot concentrated winding, the winding end can be shortened, improving the utilization rate of the winding copper wire and the overall efficiency of the motor.

[0011] The structural diagram of the inner rotor is as follows: Figure 6 As shown, since the magnetic field is directly axial, torque is generated through the interaction of the stator magnetic field in the air gap and the axial direction, eliminating the need to consider eddy current losses. The inner rotor uses 45 steel. N45EH high-performance magnets are glued to the rotor slots using high-temperature adhesive. The magnet assembly diagram is shown below. Figure 7 It consists of 10 small magnets glued together to form a toothed pole. The outer rotor is a rotor with radial magnetic flux, such as... Figure 8As shown, the radial magnetic flux provided by the outer rotor is used to insert N45EH high-performance magnets into the rotor slots. The structure diagram of the magnets is shown below. Figure 9 This structure effectively enhances the magnetic field density near the shaft, while simultaneously generating two magnetic fields along the shaft diameter within a limited space. A composite diagram of the inner and outer parts of the rotor is shown below. Figure 10 As shown in the figure, the axial magnetic field is located on the inside, the radial magnetic field is located on the outside, and the output shaft is in the center.

[0012] Under the influence of an alternating magnetic field, the stator assembly remains stationary. Its teeth and yoke employ a modular design, with pre-reserved channels within the stator yoke for cooling water passages, thereby improving heat dissipation. The motor internally contains three air gap structures: one radial air gap and two axial air gaps. These three air gaps physically isolate the rotor assembly from the stator assembly, while the radial rotor and the two axial rotors rotate synchronously during operation, thus achieving efficient electromagnetic energy conversion and output. Attached Figure Description Figure 1 This is an overall diagram of a novel three-stator axial-radial hybrid flux motor, where 1 is the left end cover, 2 is the left axial stator, 3 is the radial stator, 4 is the right end cover, 5 is the outer rotor, 6 is the right axial stator, 7 is the inner rotor, and 8 is the shaft with internal splines. Figure 2 It is an axial stator core. Figure 3 For axial stator, Figure 4 This is a coil diagram of an axial stator. Figure 5 The core of the radial stator, Figure 6 It is a radial stator coil. Figure 7 This is a diagram of the core of an axial rotor. Figure 8 This is a layered magnet diagram. Figure 9 It is a radial rotor. Figure 10 Layered magnets for radial rotors. Figure 11 This is an overall view of the axial and radial rotors after assembly.

Claims

1. A novel structure of a three-stator axial-radial hybrid flux motor: the rotor consists of two parts, each equipped with an axial magnet and a radial magnet, corresponding to the stator and circumferential stator on both sides of the axial direction, respectively.

2. The structure of a novel three-stator axial-radial hybrid flux motor according to claim 1, characterized in that: The rotor consists of two flanges connected by bolts, each with an axial magnet and a radial magnet mounted on it.

3. The structure of a novel three-stator axial-radial hybrid flux motor according to claim 2, characterized in that: The outer rotor section uses stacked silicon steel sheets to reduce eddy current losses, while the inner section uses No. 45 steel to increase the rotor output torque.

4. The structure of a novel three-stator axial-radial hybrid flux motor according to claim 2, characterized in that: The inner and outer rotors are positioned by interference fit and step at both ends to reduce eddy current losses.

5. The structure of a novel three-stator axial-radial hybrid flux motor according to claim 1, characterized in that: A three-stator structure with two stators installed in the axial direction and one in the radial direction.

6. The structure of a novel three-stator axial-radial hybrid flux motor according to claim 3, characterized in that: The stator radial winding uses a toroidal coil, utilizing the motor's axial space. The stator axial winding uses a drum-shaped coil, utilizing the motor's radial space.

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