A stator and rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure

Abstract

The present invention discloses a stator-rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor. The motor comprises a stator and a rotor, both of which are salient pole structures. The rotor and stator rotate relative to each other, forming an annular air gap between the stator and rotor. The rotor comprises a rotor core, a rotor armature winding, and rotor permanent magnets. The rotor core comprises rotor teeth and a rotor yoke. The rotor armature winding is wound around the rotor teeth using a two-phase armature winding, and the rotor permanent magnets are positioned in the slots between the two rotor teeth. The stator comprises a stator core, a stator armature winding, and stator permanent magnets. The stator core comprises stator teeth and a stator yoke. The stator armature winding is wound around the stator teeth using a three-phase armature winding, and the stator permanent magnets are positioned in the slots between the two stator teeth. This dual-salient pole structure employs the principle of magnetic field modulation, resulting in strong robustness, high torque density, and high fault tolerance.

Description

Technical Field

[0001] The present invention belongs to the field of motors, and in particular relates to a permanent magnet motor structure with dual permanent magnets and dual armature windings for stator and rotor magnetic field modulation. Background Art

[0002] In recent years, energy conservation and emission reduction have become the trend of the times, and new energy vehicles have become a key development direction for future electric vehicles. As the core power component of new energy vehicles, electric motors must possess high torque density (power density), high efficiency, and high fault tolerance. Furthermore, in the aerospace field, to reduce motor weight, extremely high power density is required. Because they operate on the principle of magnetic field modulation, magnetic field modulation motors (MFMs) exhibit high torque density and have garnered increasing research and attention in academia and industry in recent decades.

[0003] Currently, various high-torque-density field-modulated motor topologies have been proposed, based on the choice of pole ratio and permanent magnet magnetization method. These include single-gap vernier reluctance motors, single-gap dual-stator-rotor permanent magnet vernier motors, and multi-gap field-modulated motors. However, existing field-modulated motors typically contain only one set of armature windings (typically located on the stator). If the armature winding fails, torque cannot be generated, resulting in poor torque output reliability. Furthermore, in existing field-modulated motor topologies, most of the rotor contains only permanent magnets or employs only salient poles, resulting in wasted rotor space. Summary of the Invention

[0004] The present invention aims to overcome these shortcomings by providing a permanent magnet motor structure with dual permanent magnets in the stator and rotor, and dual armature windings for magnetic field modulation. This invention enables the motor to contain multiple electromagnetic torque components during normal operation, resulting in extremely high torque density. Furthermore, in the event of a failure in one armature winding, full load output is achieved by reconstructing the current of the healthy armature winding, thus providing high fault tolerance. This patented invention has broad application prospects in fields requiring motors with high torque density and fault tolerance.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] A stator-rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure, comprising a stator and a rotor both of which are salient pole structures, wherein the rotor and the stator rotate relative to each other, and an annular air gap is formed between the stator and the rotor;

[0007] The rotor comprises a rotor core, a rotor armature winding and a rotor permanent magnet. The rotor core comprises rotor teeth and a rotor yoke. The rotor armature winding is wound on the rotor teeth using a two-phase armature winding. The rotor permanent magnet is arranged in a slot between two rotor teeth.

[0008] The stator comprises a stator core, a stator armature winding and a stator permanent magnet. The stator core comprises stator teeth and a stator yoke. The stator armature winding adopts a three-phase armature winding wound on the stator teeth. The stator permanent magnet is arranged in a slot between two stator teeth.

[0009] The rotor permanent magnets and the stator permanent magnets are both distributed in a Halbach array. The magnetic field generated by the rotor permanent magnets is distributed radially, and the magnetic field generated by the stator permanent magnets is distributed radially in the same direction.

[0010] As a further improvement of the present invention, the stator armature winding is fed with a three-phase symmetrical current and is a 、i b 、i c The stator armature winding is connected in the order of i and the rotor armature winding is connected in the order of i. e 、i f The electric currents are fed into the rotor armature winding in the following order.

[0011] As a further improvement of the present invention, the current expression of each phase is:

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018]

[0019] Among them, I s is the effective value of the stator current, ω es is the electrical angular velocity of the stator armature winding, а s is the stator initial phase angle, N s is the number of stator slots, I r is the effective value of the rotor current, ω er is the electrical angular velocity of the rotor armature winding, а r is the rotor initial phase angle, N r is the number of rotor slots, ω r is the mechanical angular velocity.

[0020] As a further improvement of the present invention, the magnetic potential generated by the stator permanent magnet interacts with the rotating magnetic field generated by the stator armature winding and the rotating magnetic potential generated by the rotor armature winding through the rotating magnetic field modulated by the rotor teeth to generate torque; the magnetic potential generated by the rotor permanent magnet interacts with the rotating magnetic field generated by the stator teeth to generate torque through the rotating magnetic field modulated by the stator teeth to generate torque.

[0021] As a further improvement of the present invention, the number of pole pairs P generated by the stator permanent magnet is pms The static magnetomotive force of the tooth number N r After the magnetic field is modulated by the rotating magnetic wave formed by the rotor teeth, the rotating magnetic field generated is the same as the pole pair number P generated by the stator armature winding. as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding are P ar The fundamental wave magnetomotive force interacts to generate torque, and the number of pole pairs satisfies the formula:

[0022] |P pms ±N r |=P as =P ar (1)

[0023] The number of pole pairs generated by the rotor permanent magnet is P pmr The rotating magnetomotive force is through the number of teeth N s After the magnetic field is modulated by the magnetic wave formed by the stator teeth, the rotating magnetic field generated is the same as the pole pair number P generated by the stator armature winding. as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding are P ar The fundamental wave magnetomotive force interacts to generate torque, and the number of pole pairs satisfies the formula:

[0024] |P pmr ±N s |=P as =P ar (2)

[0025] As a further improvement of the present invention, the matching relationship between the number of slots and the number of pole pairs of the stator and rotor must satisfy formula (1) and formula (2). One feasible slot-pole matching scheme is:

[0026]

[0027] As a further improvement of the present invention,

[0028] The outer contours of the rotor teeth and the rotor yoke are both concentric arc structures;

[0029] The outer contours of the stator teeth and the stator yoke are both concentric arc structures;

[0030] The air gap is between the rotor teeth and the stator teeth.

[0031] Compared with the existing technology, it has the following advantages:

[0032] The present invention's dual-permanent-magnet, dual-armature-winding magnetic field modulation permanent magnet motor employs a double-salient-pole structure. Armature windings are located in both the stator and rotor core grooves, and permanent magnets are located in both the stator and rotor core slots. Three-phase symmetrical AC current flows through the stator armature windings, while two-phase symmetrical AC current flows through the rotor armature windings. During normal operation, the two armature windings and two sets of permanent magnets overlap to output mechanical torque, further improving torque density. Furthermore, torque can be generated even if either armature winding fails, enhancing the motor's fault tolerance. Utilizing the principle of magnetic field modulation, the motor exhibits strong robustness, high torque density, and strong fault tolerance.

[0033] Unlike conventional magnetic field modulation motors such as the single-gap vernier reluctance motor and the single-gap dual-stator-rotor permanent magnet vernier motor, which have only one set of armature windings, the stator-rotor dual permanent magnet dual-armature winding magnetic field modulation permanent magnet motor of the present invention combines the number of stator and rotor slots, the number of stator and rotor armature winding pole pairs, and the number of stator and rotor permanent magnet pole pairs to ensure that the motor contains multiple electromagnetic torque components during normal operation and has extremely high torque density. At the same time, when one set of armature windings fails, full-load output is achieved by reconstructing the current of the healthy armature winding, demonstrating high fault tolerance. This invention patent has broad application prospects in fields requiring motors with high torque density and high fault tolerance.

[0034] The motor of the present invention features high torque density and strong fault tolerance. During normal operation, the stator and rotor armature windings are powered simultaneously, interacting with the stator and rotor permanent magnets to achieve high torque density output. In the event of a stator or rotor armature winding fault, the power supply to the faulty armature winding is disconnected, and the current in the normal armature winding is reconfigured or increased, allowing the motor to still generate rated torque and achieve short-term full-load operation. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a structural schematic diagram of the present invention;

[0036] Figure 2 The star diagram of the stator armature winding of the present invention;

[0037] Figure 3 This is the star diagram of the rotor armature winding of the present invention.

[0038] Among them: 1. rotor; 1-1. rotor teeth; 1-2. rotor armature winding; 1-3. rotor permanent magnet; 2. air gap; 3. stator; 3-1. stator teeth; 3-2. stator armature winding; 3-3. stator permanent magnet. DETAILED DESCRIPTION

[0039] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the embodiments described 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 making creative efforts should fall within the scope of protection of the present invention.

[0040] The present invention includes a stator 3 and a rotor 1, and the iron cores of the stator 3 and the rotor 1 are both salient pole structures. There is an air gap 2 between the stator 3 and the rotor 1. The stator 3 includes a stator iron core, a stator armature winding 3-2 and a stator permanent magnet 3-3. The rotor 1 includes a rotor iron core, a rotor armature winding 1-2 and a rotor permanent magnet 1-3.

[0041] It should be noted that the stator and rotor proposed in the present invention are relative and are ultimately determined based on actual application scenarios and system cost considerations. In the present invention, an external rotor motor will be used as an example.

[0042] Specifically, the rotor includes a rotor core, a rotor armature winding and a rotor permanent magnet. The rotor core includes rotor teeth and a rotor yoke. The rotor armature winding adopts a two-phase armature winding wound on the rotor teeth. The rotor permanent magnet is arranged in a slot between two rotor teeth; and the rotor permanent magnet is arranged outside the rotor armature winding.

[0043] The stator includes a stator core, a stator armature winding and a stator permanent magnet. The stator core includes stator teeth and a stator yoke. The stator armature winding adopts a three-phase armature winding wound on the stator teeth. The stator permanent magnet is arranged in a slot between two stator teeth, and the stator permanent magnet is arranged outside the stator armature winding.

[0044] Both the rotor and stator permanent magnets are distributed in a Halbach array. The magnetic field generated by the rotor permanent magnet is radially distributed, and the magnetic field generated by the stator permanent magnet is radially distributed, with the same direction and pointing to the stator or rotor side at the same time.

[0045] A low-cost implementation scheme is: a three-phase symmetrical current is passed through the stator armature winding 3-2, and the current is adjusted according to i a 、i b 、i c The stator armature winding 3-2 is connected in the order of i. The rotor armature winding 1-2 is connected with two-phase symmetrical current and e 、i f The currents of each phase are expressed as follows:

[0046]

[0047]

[0048]

[0049]

[0050]

[0051]

[0052]

[0053] Among them, I s is the effective value of the stator 3 current, ω es is the electrical angular velocity of the stator armature winding 3-2, а s is the initial phase angle of stator 3, N s is the number of stator slots, I r is the effective value of the rotor 1 current, ω er is the electrical angular frequency of the rotor armature winding 1-2, а r is the initial phase angle of rotor 1, N r is the number of rotor slots, ω r is the mechanical angular velocity.

[0054] The number of pole pairs P generated by the stator permanent magnet 3-3 pms The static magnetomotive force of the tooth number N r After the magnetic field modulation is performed on the rotating magnetic wave formed by the rotor tooth 1-1, the rotating magnetic field generated and the pole pair number of the stator armature winding 3-2 is P as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding 1-2 are P ar The fundamental wave magnetomotive force interacts with each other to generate torque, which satisfies the formula:

[0055] |P pms ±N r |=P as =P ar

[0056] The number of pole pairs generated by the rotor permanent magnets 1-3 is P pmr The rotating magnetomotive force is through the number of teeth N s After the magnetic field modulation is performed on the magnetic conduction wave formed by the stator teeth 3-1, the rotating magnetic field generated and the pole pairs generated by the stator armature winding 3-2 are P as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding 1-2 are P ar The fundamental wave magnetomotive force interacts with each other to generate torque, which satisfies the formula:

[0057] |P pmr ±N s |=P as =Par

[0058] The above analysis shows that if the motor parameters are appropriately selected, four components of torque will be generated. The first two components are generated by the interaction of the rotating magnetic field generated by the stator permanent magnets 3-3, modulated by the rotor teeth 1-1, with the rotating magnetic field generated by the stator armature winding 3-2 and the rotating magnetic field generated by the rotor armature winding 1-2. The last two components are generated by the interaction of the rotating magnetic field generated by the rotor permanent magnets 1-3, modulated by the stator teeth 3-1, with the rotating magnetic field generated by the stator armature winding 3-2 and the rotating magnetic field generated by the rotor armature winding 1-2. When the four components of torque act on rotor 1 in the same direction, the combined electromagnetic torque is maximized.

[0059] The combination of the number of slots and pole pairs in the stator and rotor that satisfies the above three relationships is:

[0060]

[0061] Other slot-pole combinations that satisfy the above formula and conform to the principles described in this patent are within the scope of protection of this patent and are not listed here. In addition, this patent uses the outer rotor motor model as an example. Other models that conform to the principles described in this patent include, but are not limited to, inner rotor motors and axial magnetic field motors, all of which fall within the scope of protection of this patent.

[0062] The present invention will be further described below with reference to the accompanying drawings.

[0063] Example

[0064] See also Figure 1 The present invention includes a stator 3 and a rotor 1. An air gap 2 is provided between the stator 3 and the rotor 1. The rotor 1 includes rotor teeth 1-1, a rotor armature winding 1-2 and a rotor permanent magnet 1-3. The stator 3 includes stator teeth 3-1, a stator armature winding 3-2 and a stator permanent magnet 3-3. The rotor armature winding 1-2 adopts a two-phase armature winding wound on the rotor teeth 1-1, and the stator armature winding 3-2 adopts a three-phase armature winding wound on the stator teeth 3-1.

[0065] See also Figure 2 , Figure 2 This is the star diagram of the stator winding of the present invention. The stator 3 of the present invention has a total of 9 slots and adopts a double-layer winding. The stator winding 3-2 is a three-phase distributed winding structure. When a three-phase symmetrical alternating current is introduced, a pair of pole magnetic potential is generated.

[0066] See also Figure 3 , Figure 3 This is the star diagram of the rotor winding of the present invention. The rotor 1 of the present invention has a total of 8 slots and adopts a single-layer winding. The rotor winding 1-2 adopts a two-phase distributed winding structure. Two-phase symmetrical alternating current is introduced to generate a pair of pole magnetic potential.

[0067] The stator armature winding 3-2 is fed with a three-phase symmetrical current and is a 、i b 、i c The stator armature winding 3-2 is connected in the order of i. The rotor armature winding 1-2 is connected with two-phase symmetrical current and e 、i f The currents of each phase are expressed as follows:

[0068]

[0069]

[0070]

[0071]

[0072]

[0073]

[0074]

[0075] Among them, I s is the effective value of the stator 3 current, ω es is the electrical angular velocity of the stator armature winding 3-2, а s is the initial phase angle of stator 3, N s is the number of stator slots, I r is the effective value of the rotor 1 current, ω er is the electrical angular velocity of the rotor armature winding 1-2, а r is the initial phase angle of rotor 1, N r is the number of rotor slots, ω r is the mechanical angular velocity.

[0076] In order to better explain the working principle of this motor, Figure 1The present invention is described below. The stator and rotor poles of the motor of the present invention are matched in a 9 / 8 ratio. Three-phase symmetrical AC current flows through the stator armature winding 3-2 to generate a single pair of rotating magnetomotive force (MMF). The stator permanent magnets 3-3 generate a 9-pole magnetic field. Two-phase symmetrical AC current flows through the rotor armature winding 1-2 to generate a single pair of rotating magnetomotive force (MMF). The rotor permanent magnets 1-3 generate an 8-pole magnetic field. The 9-pole static MMF generated by the stator permanent magnets 3-3 is magnetically modulated by the rotating magnetic permeance wave formed by the eight rotor teeth 1-1. The resulting single-pole rotating magnetic field interacts with the single-pole fundamental MMF generated by the stator and rotor armature windings, generating two torque components. The 8-pole rotating MMF generated by the rotor permanent magnets 1-3 is magnetically modulated by the magnetic permeance wave formed by the nine stator teeth 3-1. The resulting single-pole rotating magnetic field interacts with the single-pole fundamental MMF generated by the stator and rotor armature windings, generating two torque components. When the four torques act on the rotor 1 in the same direction, the synthesized electromagnetic torque is the largest.

[0077] When rotor armature winding 1-2 fails, the power supply to rotor armature winding 1-2 is removed, the stator phase current is reconfigured, and the magnetomotive force of stator armature winding 3-2 interacts with the magnetomotive force of the stator and rotor permanent magnets, respectively. The motor operates as a single-pole permanent magnet synchronous motor, achieving short-term full-load operation. When stator armature winding 3-2 fails, the power supply to stator armature winding 3-2 is removed, the rotor phase current is reconfigured, and the magnetomotive force of rotor armature winding 1-2 interacts with the magnetomotive force of the stator and rotor permanent magnets, respectively. The motor also operates as a single-pole permanent magnet synchronous motor, achieving short-term full-load operation. Therefore, this new motor has strong fault tolerance and strong robustness.

[0078] The present invention utilizes the principle of magnetic field modulation and innovates the motor structure. Armature windings and permanent magnets are added to both the stator and rotor, enabling the generation of multiple electromagnetic torques. Furthermore, in the event of a stator or rotor armature winding failure, the faulty armature winding is removed and the healthy phase current is reconstructed, enabling short-term full-load operation and achieving high torque density and high fault tolerance. The motor's stator and rotor cores both utilize a salient pole structure, resulting in a relatively simple motor model that is easy to manufacture and exhibits high robustness. This invention will have broad application prospects in fields requiring high torque density and high fault tolerance.

[0079] As a preferred embodiment, the rotor tooth 1-1 and the outer contour of the rotor 1 yoke are both concentric arc structures; the stator tooth 3-1 and the outer contour of the stator 3 yoke are both concentric arc structures; and the air gap 2 is between the rotor tooth 1-1 and the stator tooth 3-1.

[0080] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0081] The above embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

[0082] It should be understood that the above description is for illustrative purposes only and is not intended to be limiting. Many embodiments and many applications beyond the examples provided will be apparent to those skilled in the art upon reading the above description. Therefore, the scope of the present teachings should not be determined with reference to the above description, but rather with reference to the preceding claims and the full scope of equivalents to which such claims are entitled. For the purpose of completeness, all articles and references, including disclosures of patent applications and publications, are incorporated herein by reference. The omission of any aspect of the subject matter disclosed herein from the preceding claims is not a disclaimer of such subject matter, nor should it be considered that the applicants did not consider such subject matter to be part of the disclosed inventive subject matter.

Claims

1. A stator and rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure, characterized in that: It includes a stator and a rotor both of which are salient pole structures. The rotor and the stator rotate relative to each other, and an annular air gap is formed between the stator and the rotor. The rotor comprises a rotor core, a rotor armature winding and a rotor permanent magnet. The rotor core comprises rotor teeth and a rotor yoke. The rotor armature winding is wound on the rotor teeth using a two-phase armature winding. The rotor permanent magnet is arranged in a slot between two rotor teeth. The stator comprises a stator core, a stator armature winding and a stator permanent magnet. The stator core comprises stator teeth and a stator yoke. The stator armature winding adopts a three-phase armature winding wound on the stator teeth. The stator permanent magnet is arranged in a slot between two stator teeth. The rotor permanent magnets and the stator permanent magnets are both distributed in an array, the magnetic field generated by the rotor permanent magnets is radially distributed, and the magnetic field generated by the stator permanent magnets is radially distributed, and the directions are the same; The stator armature winding is fed with three-phase symmetrical current and is a 、i b 、i c The stator armature winding is connected in the order of i and the rotor armature winding is connected in the order of i. e 、i f The order is passed into the rotor armature winding in sequence; The magnetic potential generated by the stator permanent magnet interacts with the rotating magnetic field generated by the stator armature winding and the rotating magnetic potential generated by the rotor armature winding through the rotating magnetic field modulated by the rotor teeth to generate torque; the magnetic potential generated by the rotor permanent magnet interacts with the rotating magnetic field generated by the stator teeth to generate torque through the rotating magnetic field modulated by the stator teeth to generate torque; The number of pole pairs P generated by the stator permanent magnet pms The static magnetomotive force of the tooth number N r After the magnetic field is modulated by the rotating magnetic wave formed by the rotor teeth, the rotating magnetic field generated is the same as the pole pair number P generated by the stator armature winding. as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding are P ar The fundamental wave magnetomotive force interacts to generate torque, and the number of pole pairs satisfies the formula: |P pms ±N r |=P as =P ar (1) The number of pole pairs generated by the rotor permanent magnet is P pmr The rotating magnetomotive force is through the number of teeth N s After the magnetic field is modulated by the magnetic wave formed by the stator teeth, the rotating magnetic field generated is the same as the pole pair number P generated by the stator armature winding. as The fundamental magnetomotive force and the number of pole pairs generated by the rotor armature winding are P ar The fundamental wave magnetomotive force interacts to generate torque, and the number of pole pairs satisfies the formula: |P pmr ±N s |=P as =P ar (2)。 2. The stator-rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure according to claim 1 is characterized in that: The expression of each phase current is: Among them, I s is the effective value of the stator current, ω es is the electrical angular velocity of the stator armature winding, а s is the stator initial phase angle, N s is the number of stator slots, I r is the effective value of the rotor current, ω er is the electrical angular velocity of the rotor armature winding, а r is the rotor initial phase angle, N r is the number of rotor slots, ω r is the mechanical angular velocity.

3. The stator-rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure according to claim 1, characterized in that: The relationship between the number of slots and the number of pole pairs of the stator and rotor must satisfy formula (1) and formula (2). One feasible slot-pole matching scheme is:

4. The stator-rotor dual permanent magnet dual armature winding magnetic field modulation permanent magnet motor structure according to claim 1, characterized in that: The outer contours of the rotor teeth and the rotor yoke are both concentric arc structures; The outer contours of the stator teeth and the stator yoke are both concentric arc structures; The air gap is between the rotor teeth and the stator teeth.

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