Stator unit phase modularized fault-tolerant permanent magnet hub motor

Abstract

The invention discloses a stator unit phase modularized fault-tolerant permanent magnet hub motor, and belongs to the technical field of motors. The motor comprises a consequent-pole permanent magnet rotor and a stator. The consequent pole permanent magnet rotor is formed by alternately arranging rotor salient pole iron cores and permanent magnets; the stator comprises a plurality of slotted stator modules, each stator module is provided with a large slot and a small slot which are formed by stator teeth and yoke parts and are used for placing a single-phase armature winding, the teeth at the end parts of the stator modules are not wound by the winding, and the teeth at the end parts of the two stator modules are assembled to serve as fault-tolerant teeth; an independent air gap is formed between the consequent pole permanent magnet rotor and the stator module; the armature windings on the single stator module are connected end to end to form a phase; the plurality of stator modules are sequentially arranged in the circumferential direction to form a plurality of phases of the motor; the motor mechanism can solve the problems that a traditional motor is large in permanent magnet consumption, large in interphase coupling, poor in fault-tolerant capability, difficult to machine and assemble and the like, and facilitates improvement of the permanent magnet utilization rate and operation reliability of the motor.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet motor technology, and in particular to a stator unit phase modular fault-tolerant permanent magnet hub motor. Background Technology

[0002] The complexity of permanent magnet motors' operating conditions presents significant challenges to their design, including issues such as fault tolerance and cost. Direct-drive hub motors, by eliminating the intermediate mechanical transmission system, are widely used in automotive distributed drive systems. In external rotor permanent magnet synchronous motors, the permanent magnets are typically placed on the external rotor; however, the permanent magnets are attached to the entire inner circle of the external rotor, leading to problems such as large permanent magnet usage and even-order harmonic back EMF caused by alternating pole permanent magnet rotors. This paper presents a stator unit phase-modular fault-tolerant permanent magnet hub motor. Summary of the Invention

[0003] Purpose of the invention: The purpose of this invention is to provide a stator unit phase modular fault-tolerant permanent magnet hub motor, which solves the problems of large permanent magnet usage, high cost, and large inter-phase coupling in traditional permanent magnet motors, reduces the cost of the motor and drive system, improves the motor's post-failure performance and operational reliability, and simplifies the processing, transportation and assembly process.

[0004] Technical Solution: A modular stator-unit fault-tolerant permanent magnet hub motor includes an alternating pole permanent magnet rotor and a stator. The alternating pole permanent magnet rotor consists of a rotor salient pole iron core and permanent magnets arranged alternately. The stator includes several slotted stator modules. Each stator module has slots of varying sizes formed by stator teeth and a yoke for accommodating single-phase armature windings. The end teeth of the stator modules do not wind the windings. The end teeth of two stator modules are assembled to serve as fault-tolerant teeth. An independent air gap is formed between the alternating pole permanent magnet rotor and the stator modules. The armature windings on a single stator module are connected end-to-end to form a phase. Several stator modules are arranged sequentially in a circumferential direction to form several phases of the motor. The fault-tolerant teeth between every two modules ensure that each module is spaced 360° / M electrical degrees apart, where M is the number of phases of the motor. Several phase windings are supplied with several symmetrical currents to drive the rotor to rotate, realizing electromechanical energy conversion.

[0005] Furthermore, each stator module consists of several large teeth, small teeth, and a yoke. The stator module has large teeth and small teeth distributed on it. Several phase armature windings are wound on the large teeth, while the small teeth are not wound.

[0006] Furthermore, the small teeth at the end of the stator module and the small teeth on the adjacent stator module form a fault-tolerant tooth, which can achieve physical isolation between phase windings.

[0007] Furthermore, the large tooth span on the stator module is one pole pitch, and the small tooth span is 360 / M electrical degrees, so that each phase is spaced 360 / M electrical degrees apart, and several stator modules form several symmetrical M-phase windings.

[0008] Furthermore, the stator and rotor are made of silicon steel sheets axially stacked.

[0009] Furthermore, the permanent magnets have the same magnetization direction, and each stator module is first wound with wire and then assembled.

[0010] Compared with the prior art, the significant advantages of this invention are as follows: 1. In the present invention, the stator of a modular fault-tolerant permanent magnet hub motor is composed of several stator modules, and the fault-tolerant teeth formed by assembling the small teeth at the ends of the stator modules do not require winding. The stator modules can be wound first and then assembled, which simplifies the processing and assembly process. 2. The present invention provides a stator unit phase modular fault-tolerant permanent magnet hub motor that uses an alternating pole permanent magnet rotor. While ensuring the electromagnetic performance of the motor, it reduces the amount of permanent magnets used and lowers the cost of the motor. In addition, the effective air gap of the motor is reduced and the inductance is increased, which can effectively suppress short-circuit current and improve the reliability of motor operation. 3. In the stator unit phase modular fault-tolerant permanent magnet hub motor of the present invention, the end teeth of the stator module and the small teeth on the adjacent stator module form a fault-tolerant small tooth. This small tooth can realize the physical isolation between phase windings, reduce phase interference, and improve motor performance. 4. In the stator module of the present invention, the large tooth span of the stator module is one pole pitch, which increases the winding coefficient of the motor. In addition, the positive and negative coil sides on each large stator tooth with a span of one pole pitch can eliminate the even harmonics induced by the alternating pole permanent magnet rotor. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the cross-section and winding connection of a traditional permanent magnet motor; Figure 2 This is a schematic diagram of the cross-section and winding connection of a stator unit phase modular fault-tolerant permanent magnet hub motor according to the present invention; Figure 3 This invention relates to a modular stator with two A-phase phases, a cross-sectional view of an alternating pole rotor, and a schematic diagram of the A-phase winding connection in a modular fault-tolerant permanent magnet hub motor. Figure 4 This is a diagram showing the magnetic field distribution of a traditional permanent magnet hub motor after the A-phase winding is energized. Figure 5 This is a diagram showing the distribution of magnetic field lines in the A-phase winding of a stator unit phase modular fault-tolerant permanent magnet hub motor after energization, according to the present invention. Detailed Implementation

[0012] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.

[0013] like Figure 1 The diagram shows the cross-section and winding connection of a traditional permanent magnet motor. In the diagram, 1, 2, 3, 4, and 5 are the five stator teeth in the unit motor where the windings of the same phase (phase A, phase B, phase C, phase D, and phase E) are wound.

[0014] like Figure 2 As shown, this invention discloses a stator unit phase modular fault-tolerant permanent magnet hub motor, using a five-phase 50-slot 44-pole motor (two 25-slot 22-pole five-phase unit motors) as an example. In this embodiment, the motor includes an alternating pole permanent magnet rotor and slotted stator modules (9, 10, 11, 12, 13, 14, 15, 16, 17, 18). The alternating pole permanent magnet rotor consists of alternating rotor salient pole iron cores 6 and permanent magnets 7. The stator includes several stator modules, each with stator teeth and a yoke forming slots of varying sizes for accommodating single-phase armature windings. The end teeth of the stator modules do not wind the windings; the teeth at the ends of two stator modules, when assembled, act as fault-tolerant teeth, achieving physical isolation between the armature windings of each phase and improving the reliability of motor operation. An independent air gap 8 is formed between the alternating pole permanent magnet rotor and the stator modules. The armature windings on a single stator module are connected end-to-end to form one phase; several stator modules are arranged sequentially in a circumferential direction to form several phases of the motor; the allowable teeth between every two stator modules ensure that the interval between each stator module is exactly 360 / M electrical degrees (M is the number of phases of the motor), and that the windings of the M phases differ by 360 / M electrical degrees, forming an M-phase symmetrical armature winding. The large tooth span on the stator module is one pole pitch, increasing the winding coefficient of the motor; in addition, the positive and negative coil sides on each large stator tooth can eliminate even harmonics induced by the alternating pole permanent magnet rotor; The following is combined with Figure 2 and 3 The winding connection method of this motor is explained in detail below: This embodiment uses a five-phase motor as an example, such as... Figure 2 The stator modules shown have in-phase armature windings wound on them. Stator modules 9 and 14 have A-phase armature windings wound on them; stator modules 10 and 15 have B-phase armature windings wound on them; stator modules 11 and 16 have C-phase armature windings wound on them; stator modules 12 and 17 have D-phase armature windings wound on them; and stator modules 13 and 18 have E-phase armature windings wound on them.

[0015] like Figure 3As shown, stator teeth F1, F3, F5, and F7 are wound with A+ coils (A+ represents the positive coil of phase A; other coil identifiers can be deduced similarly), and stator teeth F2, F4, F6, and F8 are wound with A- coils. The coils on these eight teeth are connected end-to-end to form the phase A winding. The four-phase armature windings on other stator modules can be connected according to the winding potential star diagram. The difference between this invention and traditional motors is that the small teeth at the connection point of the two stator modules after assembly do not have armature windings, which can act as fault-tolerant teeth, achieving physical isolation between phases and ensuring the reliability of motor operation. The large teeth on the stator modules have a span of one pole pitch, increasing the winding coefficient of the motor; furthermore, the positive and negative coil sides on each large tooth with a span of one pole pitch can eliminate even harmonics induced by the alternating pole permanent magnet rotor.

[0016] This invention reduces the effective air gap of the motor by using an alternating pole permanent magnet rotor, increases the motor's inductance, effectively suppresses short-circuit fault current, and improves the reliability of motor operation.

[0017] Figure 4 and 5 The magnetic field distribution diagrams are given for both the conventional motor and the motor structure of this invention patent when the A-phase winding is energized alone. Figure 4 The motor is divided into two units, upper and lower, by the dashed line. For ease of explanation, the traditional motor structure diagram and the magnetic field distribution diagram after phase A of the traditional motor is energized only show the stator winding of the unit motor above the dashed line (the stator winding distribution of the unit motor below the dashed line is exactly the same as that of the unit motor above the dashed line).

[0018] from Figure 5 As can be seen from this, the motor structure using this invention reduces the interphase electromagnetic frequency and improves the motor's ability to operate after a fault.

[0019] The above embodiments are merely illustrative of the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. For example, the permanent magnet on the alternating pole rotor can have various structures, as long as the permanent magnet can form a pair of magnetic fields with the adjacent rotor salient pole. The present invention patent has been illustrated using a three-phase unit motor as an example. The present invention patent can be extended to multi-winding harmonic hybrid excitation permanent magnet motors with M-phase pole slot cooperation. In addition, this concept can also be extended to various motors such as axial flux and linear motors. Any modifications made to the technical solution based on the technical concept proposed in the present invention fall within the scope of protection of the present invention.

Claims

1. A stator unit phase modular fault-tolerant permanent magnet hub motor, characterized in that, It includes an alternating pole permanent magnet rotor and a stator; the alternating pole permanent magnet rotor consists of a rotor salient pole iron core (6) and permanent magnets (7) arranged alternately; the stator includes several slotted stator modules, each stator module has slots of different sizes formed by stator teeth and yoke for placing single-phase armature windings, the end teeth of the stator modules do not wind the windings, and the teeth at the ends of two stator modules are assembled to serve as fault-tolerant teeth; an independent air gap (8) is formed between the alternating pole permanent magnet rotor and the stator modules; the armature windings on a single stator module are connected end to end to form a phase; several stator modules are arranged in a circumferential direction to form several phases of the motor; the fault-tolerant teeth between every two modules make each module spaced 360 / M electrical degrees apart, where M is the number of phases of the motor; several phase windings are supplied with several symmetrical currents to drive the rotor to rotate, realizing electromechanical energy conversion.

2. The stator unit phase modular fault-tolerant permanent magnet hub motor according to claim 1, characterized in that, Each stator module consists of several large teeth, small teeth, and a yoke. The stator module has large teeth and small teeth distributed on it. Several phase armature windings are wound on the large teeth, while the small teeth are not wound.

3. The stator unit phase modular fault-tolerant permanent magnet hub motor according to claim 1, characterized in that, The small teeth at the end of the stator module and the small teeth on the adjacent stator module form a fault-tolerant tooth, which can achieve physical isolation between phase windings.

4. The stator unit phase modular fault-tolerant permanent magnet hub motor according to claim 1, characterized in that, The large tooth span on the stator module is one pole pitch, and the small tooth span is 360 / M electrical degrees, so that each phase is spaced 360 / M electrical degrees apart. Several stator modules form several symmetrical M-phase windings.

5. The stator unit phase modular fault-tolerant permanent magnet hub motor according to any one of claims 1-4, characterized in that, The stator and rotor are made of silicon steel sheets axially stacked.

6. The stator unit phase modular fault-tolerant permanent magnet hub motor according to any one of claims 1-4, characterized in that, The permanent magnets have the same magnetization direction, and each stator module is first wound with wire and then assembled.

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