A structure of a stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor

Abstract

The present invention discloses a structure of a stator-rotor dual-armature winding multi-electromagnetic torque single-air-gap reluctance motor, which includes a stator and a rotor both having salient pole structures. The rotor is sleeved on the outer periphery of the stator, and there is an air gap between the stator and the rotor. The rotor includes a rotor core and a rotor armature winding. The rotor core protrudes inward to form rotor teeth, and the rotor armature winding is wound on the rotor teeth in the structure of a fractional-slot concentrated winding. The stator includes a stator core and a stator armature winding. The stator core protrudes outward to form stator teeth, and the stator armature winding is wound on the stator teeth in the structure of a three-phase symmetrical winding. During normal operation, the two sets of windings are superimposed to output mechanical torque, further improving the torque density, and torque can also be generated when any one set of windings fails, improving the fault tolerance of the motor.

Description

Technical Field

[0001] The present invention belongs to the field of motors, and particularly relates to a structure of a stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor. Background Art

[0002] In recent years, under the dual pressures of energy conservation and emissions, new energy vehicles have become an important development direction for future electric vehicles. As the core power component of new energy vehicles, the motors used in new energy vehicles are required to have high torque density (power density), high efficiency, high fault tolerance, etc. Permanent magnet motors have received extensive attention from researchers due to their large torque density and high power factor. However, the high price of permanent magnet materials and the risk of demagnetization at high temperatures make the cost of permanent magnet motors high and the failure rate high. Traditional switched reluctance motors have the advantages of simple structure and low price, but they have the defects of large noise, vibration, and torque ripple. In recent years, field modulation motors based on the principle of field modulation have received high attention. The DC-biased vernier reluctance motor is one of them. It passes DC and AC components into the same coil, makes full use of the current-carrying capacity of the conductor, and improves the output torque at the same copper loss.

[0003] In addition, most existing types of motors, such as electrically excited synchronous motors, synchronous reluctance motors, switched flux, flux reversal motors, permanent magnet motors, etc., only contain a set of armature windings and have poor fault tolerance performance. To improve the fault tolerance of motors, the existing technical solutions generally increase the number of phases of the stator-side windings or increase the number of sets of stator-side windings. This causes conflicts in the stator space and waste in the rotor-side space. Summary of the Invention

[0004] The purpose of the present invention is to overcome the above deficiencies and provide a structure of a stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor. During normal operation, the two sets of windings are superimposed to output mechanical torque, further improving the torque density, and torque can also be generated when any set of windings fails, improving the fault tolerance of the motor.

[0005] To achieve the above purpose, the present invention adopts the following technical solutions:

[0006] A structure of a stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor, including a stator and a rotor both having salient pole structures. The rotor is sleeved on the outer periphery of the stator, and there is an air gap between the stator and the rotor;

[0007] The rotor includes a rotor core and a rotor armature winding. The rotor core includes protruding rotor teeth and a rotor yoke. The rotor armature winding is wound around the rotor teeth in the structure of a fractional-slot concentrated winding;

[0008] The stator includes a stator core and a stator armature winding. The stator core includes protruding stator teeth and a stator yoke. The stator armature winding is wound around the stator teeth in a three-phase symmetric winding structure.

[0009] The rotor armature winding is a two-phase winding, and a composite current of alternating current superimposed with a direct current component is applied. The composite current is applied to the rotor armature winding in sequence according to i A+ , i B+ , i A- , i B- ; A three-phase symmetric current is applied to the stator armature winding, and it is applied to the stator armature winding in sequence according to i D , i E , i F .

[0010] The expressions of each phase current are as follows:

[0011]

[0012]

[0013]

[0014]

[0015]

[0016]

[0017]

[0018] ω e = N s ω r

[0019] ω es = P as ω r

[0020] Among them, I ac is the effective value of the alternating current component of the rotor, I dc is the average value of the direct current component, w e is the electrical angular frequency of the rotor armature winding, а is the initial phase angle of the stator, I acs is the effective value of the stator current, w es is the electrical angular frequency of the stator armature winding, а s is the initial phase angle of the stator, N s is the number of stator slots, P as is the number of pole pairs of the stator armature winding, w r is the mechanical angular velocity.

[0021] The number of pole pairs P generated by the DC component of the rotor armature winding dc The stationary magnetomotive force passes through the number of teeth N s of the stator teeth. After magnetic field modulation by the permeance wave formed by the stator teeth, the generated rotating excitation magnetic field and the number of pole pairs P аr of the fundamental magnetomotive force of the AC component of the rotor armature winding satisfy the relationship:

[0022] P ar = |N s ± P dc | (1)

[0023] The number of pole pairs P as of the stator winding. After passing through alternating current, a stator rotating magnetic potential with P as pairs of poles is formed. When the number of pole pairs of the unmodulated DC rotating magnetic field generated by the rotor DC component is the same, that is, when the following formula is satisfied, a stator electromagnetic torque will be generated;

[0024] P dc = P as (2)

[0025] When the number of rotor slots N r and the number of pole pairs of the stator armature winding is P as satisfy the following formula, a reluctance torque component similar to the synchronous reluctance torque will be generated;

[0026] N r = 2P as (3)

[0027] After the stator winding passes through alternating current, the formed stator rotating magnetic potential with P as pairs of poles passes through the permeance wave formed by the stator teeth with the number of teeth N s for magnetic field modulation. When the number of pole pairs of the generated rotating magnetic field is the same as that of the rotating magnetic field generated by the rotor AC component, that is, when the following formula is satisfied, a stator electromagnetic torque will be generated, and the expression is as follows:

[0028] P ar = |N s ± P as | (4)

[0029] The number of stator slots N s and the number of rotor slots N r satisfy the formula:

[0030] N s = k1m s

[0031] N r = k2m r

[0032] where k1 and k2 are integers, and m s is the number of AC phases of the stator armature winding, and m r is the number of AC phases of the rotor armature winding.

[0033] The relationship between the number of slots and the number of pole pairs of the stator and rotor is as follows:

[0034]

[0035] The outer contours of the rotor teeth and the rotor yoke are both concentric arc structures;

[0036] The outer contours of the stator teeth and the stator yoke are both concentric arc structures;

[0037] The air gap is between the outer contours of the rotor teeth and the stator teeth.

[0038] The rotor armature winding is a two-phase winding, and two adjacent rotor armature windings are connected to form phase A+, phase A-, phase B+ and phase B- in sequence.

[0039] The stator armature winding is a three-phase winding, and the stator armature windings are connected in sequence to form phase D, phase E, and phase F.

[0040] Compared with the prior art, it has the following advantages:

[0041] The present invention has a doubly salient structure and adopts the principle of magnetic field modulation, with strong robustness and high torque density. Windings are arranged in both the stator core grooves and the rotor core grooves. The current passed through the stator armature winding contains a DC part and an AC part, and three-phase alternating current is passed through the rotor armature winding. During normal operation, the two sets of windings work simultaneously to output mechanical torque in superposition, further improving the torque density, and torque can also be generated when any set of windings fails, improving the fault tolerance of the motor.

[0042] The motor of the present invention has high torque density, strong fault tolerance, and can achieve multi-modal operation. During normal operation, the stator and rotor armature windings are powered simultaneously to achieve high torque density and high efficiency output. When a fault occurs in the stator or rotor armature winding of the motor, the power supply of the faulty winding is cut off, and torque can still be generated. When a fault occurs in the rotor armature winding, the power supply of the rotor armature winding is cut off, and the current of the healthy phase winding is reconstructed. The motor operates as a synchronous reluctance motor and realizes short-time full-load operation; when a fault occurs in the stator armature winding, the power supply of the stator armature winding is cut off, and the motor operates as a DC-biased vernier reluctance motor and realizes short-time full-load operation.

[0043] Different from existing motor types such as switched reluctance motors and electrically excited synchronous motors that only have one set of armature windings, the dual-armature-winding multi-electromagnetic-torque single-stator single-rotor reluctance motor can have multiple electromagnetic torque components during normal operation by selecting the combination of the number of stator and rotor slots and the number of pole pairs of the stator and rotor armature windings, and has extremely high torque density. At the same time, when one set of windings fails, full-load output can be achieved by reconstructing or increasing the current configuration of the healthy windings, ensuring sufficient fault tolerance performance. This invention will have broad application prospects in application scenarios that require motors to have high torque density and high fault tolerance, including but not limited to vehicle in-wheel motor drive systems, aerospace, deep-sea exploration, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 is a schematic structural diagram of the present invention;

[0045] Figure 2 is a schematic diagram of the rotor winding connection;

[0046] Figure 3 is a schematic diagram of the stator winding connection.

[0047] Wherein: 1, rotor armature winding; 2, rotor; 2-1, rotor teeth; 3, air gap; 4, stator; 4-1, stator teeth; 5, stator armature winding. DETAILED DESCRIPTION OF THE INVENTION

[0048] The structure of a stator-rotor dual-armature-winding multi-electromagnetic-torque single-air-gap reluctance motor of the present invention includes a stator and a rotor. Both the stator and rotor iron cores are salient pole structures, and there is an air gap between the stator and rotor. The rotor includes a rotor iron core and a rotor armature winding. The rotor iron core protrudes inward to form rotor teeth, and the rotor armature winding is wound around the rotor teeth in the structure of a fractional-slot concentrated winding; the stator includes a stator iron core and a stator armature winding. The stator iron core protrudes outward to form stator teeth, and the stator armature winding is wound around the stator teeth in the structure of a three-phase symmetrical winding.

[0049] It should be noted that the stator and rotor proposed by the present invention are relative and are finally determined according to the actual application scenario and system cost considerations.

[0050] As a low-cost implementation: The composite current is passed into the rotor armature winding in the order of i A+ , i B+ , i A- , i B- ; The stator armature winding is passed with a three-phase symmetrical current and in the order of i D , i E , i FThey are sequentially fed into the stator armature winding in the order of... The rotor armature winding is a two-phase winding, and a composite current of alternating current superimposed with a direct current component is fed through feasible devices such as brush slip rings and resolvers. The expressions of the currents in each phase are as follows:

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058] ω e = N s ω r

[0059] ω es = P as ω r

[0060] Among them, I ac is the effective value of the alternating current component of the rotor, I dc is the average value of the direct current component, w e is the electrical angular frequency of the rotor armature winding, а is the initial phase angle of the stator, I acs is the effective value of the stator current, w es is the electrical angular frequency of the stator armature winding, а s is the initial phase angle of the stator, N s is the number of stator slots, P as is the number of pole pairs of the stator armature winding, w r is the mechanical angular velocity.

[0061] The stationary magnetomotive force generated by the direct current component of the rotor armature winding with P dc pole pairs passes through the magnetic conductance wave formed by the stator teeth with N s teeth for magnetic field modulation, and the generated rotating excitation magnetic field and the fundamental wave magnetomotive force generated by the alternating current component of the rotor armature winding with P аr pole pairs satisfy the relationship:

[0062] P ar = |N s ± P dc |

[0063] The number of pole pairs of the stator armature winding is Pas After alternating current is applied, a stator rotating magnetic potential of P as opposite poles is formed. When the pole pairs of the stator rotating magnetic potential are the same as those of the unmodulated DC rotating magnetic field generated by the DC component of the rotor, that is, when the following formula is satisfied, stator electromagnetic torque will be generated.

[0064] P dc = P as

[0065] When the number of rotor slots N r and the pole pairs of the stator armature winding are P as satisfy the following formula, a reluctance torque component similar to the synchronous reluctance torque will be generated.

[0066] N r = 2P as

[0067] After alternating current is applied to the stator winding, the stator rotating magnetic potential of P as opposite poles, after being field-modulated by the permeance wave formed by the stator teeth with the number of teeth N s When the pole pairs of the generated rotating magnetic field are the same as those of the rotating magnetic field generated by the AC component of the rotor, that is, when the following formula is satisfied, stator electromagnetic torque will be generated.

[0068] P ar = |N s ± P as |

[0069] The above analysis shows that if the motor parameters are properly selected, four parts of torque will be generated. One is the torque generated by the interaction between the rotating magnetic field modulated by the DC component of the rotor armature winding through the stator teeth and the rotating magnetic field generated by the AC component of the rotor armature winding; the second is the electromagnetic torque generated by the interaction between the unmodulated DC rotating magnetic field generated by the DC component of the rotor armature winding and the AC quantity of the stator armature winding; the third is the reluctance torque component formed by the AC quantity of the stator armature winding and the rotor salient poles; the fourth is the torque generated by the interaction between the rotating magnetomotive force generated by the AC quantity of the stator armature winding and the rotating magnetic field generated by the AC component of the rotor after being modulated by the stator teeth. When the directions of the four parts of torque acting on the rotor are the same, the synthesized electromagnetic torque is the largest.

[0070] A combination of the number of stator and rotor slots and the number of pole pairs that satisfies the above three relationships is:

[0071] <![CDATA[Number of stator slots N s > <![CDATA[Number of rotor slots N r > <![CDATA[Number of pole pairs P of the stator armature winding as > <![CDATA[Number of pole pairs P of the rotor armature winding ar > <![CDATA[Number of DC pole pairs P of the rotor dc > 9 8 4 5 4

[0072] Among them, the number of stator and rotor slots satisfies the formula:

[0073] N s = k1m s

[0074] N r= k2m r

[0075] where k1 and k2 are integers, and m s is the number of AC phases of the stator armature winding, and m r is the number of AC phases of the rotor armature winding.

[0076] In addition, all slot-pole combinations that satisfy the above six formulas and conform to the principles described in this patent are within the scope of protection of this patent, and will not be listed here. In addition, taking the outer-rotor motor model of this patent as an example, those that conform to the principles described in this patent include, but are not limited to, inner-rotor motors and axial-field motors, and are all within the scope of protection of this patent.

[0077] The present invention will be further described below with reference to the accompanying drawings.

[0078] Embodiment

[0079] Referring to Figure 1 , the present invention includes a stator 4 and a rotor 2. There is an air gap 3 between the stator 4 and the rotor 2. The rotor 2 includes rotor teeth 2-1 and a rotor armature winding 1. The stator 4 includes stator teeth 4-1 and a stator armature winding 5. The rotor armature winding 1 is wound around the rotor teeth 2-1 in a fractional-slot concentrated winding structure, and the stator armature winding 5 is wound around the stator teeth 4-1 in a three-phase symmetric winding structure.

[0080] The composite current is sequentially fed into the rotor armature winding in the order of i A+ , i B+ , i A- , i B- . The stator armature winding is fed with a three-phase symmetric current and is sequentially fed into the stator armature winding in the order of i D , i E , i F . The rotor armature winding is a two-phase winding, and a composite current of AC superimposed with a DC component is fed through a feasible device such as a brush slip ring or a rotary transformer. The expressions of each phase current are:

[0081]

[0082]

[0083]

[0084]

[0085]

[0086]

[0087]

[0088] ω e = N s ω r

[0089] ω es = P as ω r

[0090] wherein, I ac is the effective value of the alternating current component of the rotor, I dc is the average value of the direct current component, w e is the electrical angular frequency of the rotor, а is the initial phase angle of the stator, I acs is the effective value of the stator current, w es is the electrical angular frequency of the stator, а s is the initial phase angle of the stator, N s is the number of stator slots, P as is the number of pole pairs of the stator armature winding, w r is the mechanical angular velocity.

[0091] To better explain the working principle of this motor, the following will describe the present invention in conjunction with the attached Figure 1 illustrations.

[0092] For the motor of the present invention, the slot-pole combination of the stator and rotor is 9 / 8. The direct current component in the rotor armature winding generates a rotating magnetic motive force with 4 pole pairs, and the alternating current component generates a rotating magnetic motive force with 5 pole pairs. The stator armature winding generates a rotating magnetic motive force with 4 pole pairs. The 4-pole stationary magnetic motive force generated by the direct current component of the rotor armature winding, after being modulated by the stator tooth magnetic field, generates a 5-pole rotating magnetic field that couples with the rotor alternating current component magnetic field to generate the first part of the torque component; the 4-pole rotating magnetic motive force generated by the direct current component of the rotor armature winding without modulation couples with the 4-pole rotating magnetic field generated by the alternating current component of the stator armature winding to generate the second part of the torque component; the third part of the reluctance torque component formed by the alternating current component of the stator armature winding and the rotor salient poles; the 4-pole rotating magnetic motive force generated by the stator armature winding, after being modulated by the stator teeth, generates a 5-pole rotating magnetic field that couples with the 5-pole rotating magnetic field generated by the rotor alternating current component to generate the fourth part of the torque. When the directions of the four parts of the torque acting on the rotor are the same, the synthesized electromagnetic torque is the largest.

[0093] As Figure 2 and Figure 3 shown, the rotor armature winding is a two-phase winding, and adjacent two rotor armature windings are connected to form the A+ phase, A- phase, B+ phase, and B- phase in sequence. The stator armature winding is a three-phase winding, and the stator armature windings are connected in sequence to form the D phase, E phase, and F phase.

[0094] When a fault occurs in the rotor armature winding, the power supply to the rotor armature winding is cut off, and the healthy phase current is reconstructed. The motor operates as an 8-pole synchronous reluctance motor, enabling short-time full-load operation. When a fault occurs in the stator armature winding, the power supply to the stator armature winding is cut off, and the motor operates as a two-phase DC-biased vernier reluctance motor, enabling short-time full-load operation. Therefore, this new type of motor has strong fault-tolerant performance and high robustness.

[0095] Through the improvement of the motor structure, the present invention adds a dual-armature winding to generate multiple electromagnetic torques. When a fault occurs in the stator or rotor armature winding, short-time full-load operation can still be achieved through the reconstruction of the healthy phase current, realizing high torque density and high fault-tolerance ability of the motor. The stator and rotor cores of the motor both adopt salient-pole structures, and the motor model is relatively simple, facilitating processing and having high robustness. The present invention will have a wide application prospect in application scenarios with high torque density and high fault-tolerance ability.

[0096] The above is only a preferred embodiment of the present invention and is not limited to the scope of implementation of the present invention. All equivalent changes and modifications made according to the content of the scope of the present invention shall fall within the technical scope of the present invention.

[0097] The implementation mode of the present invention is only an exemplary illustration of this patent and does not limit its protection scope. Those skilled in the art can also make partial changes to it, as long as they do not exceed the spiritual essence of this patent, they are within the protection scope of this patent.

Claims

1. A structure of a stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor, characterized in that, It includes a stator and a rotor both of which are salient pole structures. The rotor is sleeved on the outer periphery of the stator, and there is an air gap between the stator and the rotor; The rotor includes a rotor core and a rotor armature winding. The rotor core includes protruding rotor teeth and a rotor yoke. The rotor armature winding is wound around the rotor teeth in the structure of a fractional-slot concentrated winding; The stator includes a stator core and a stator armature winding. The stator core includes protruding stator teeth and a stator yoke. The stator armature winding is wound around the stator teeth in the structure of a three-phase symmetrical winding; The rotor armature winding is a two-phase winding, and a composite current of alternating current superimposed with a direct current component is passed through. The composite current is passed through the rotor armature winding in sequence according to i A+、 i B+、 i A-、 i B- ; A three-phase symmetrical current is passed through the stator armature winding, and it is passed through the stator armature winding in sequence according to i D、 i E、 i F ; The number of stator slots N s , the number of rotor slots N r satisfies the formula: In the formula, k 1, k 2 is an integer, m s is the number of stator armature winding AC phases, m r is the number of rotor armature winding AC phases.

2. The structure of the stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, characterized in that The current expressions of each phase are: Among them, I ac is the effective value of the alternating current component of the rotor, I dc is the average value of the direct current component, w e is the electrical angular frequency of the rotor armature winding, а is the initial phase angle of the stator, I acs is the effective value of the stator current, w es is the electrical angular frequency of the stator armature winding, а s is the initial phase angle of the stator, N s is the number of stator slots, P as is the number of pole pairs of the stator armature winding, w r is the mechanical angular velocity.

3. The structure of the stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, characterized in that The number of pole pairs generated by the DC component of the rotor armature winding P dc The stationary magnetomotive force of passes through the number of teeth N s After the magnetic field modulation by the magnetic conductance wave formed by the stator teeth of, the generated rotating excitation magnetic field and the fundamental wave magnetomotive force of the number of pole pairs generated by the AC component of the rotor armature winding P аr satisfy the relationship: （1） Number of pole pairs of the stator winding Pas , after alternating current is applied, it forms Pas pairs of pole stator rotating magnetic potential. When the number of pole pairs is the same as that of the unmodulated DC rotating magnetic field generated by the rotor DC component, that is, when the following formula is satisfied, stator electromagnetic torque will be generated; （2） When the number of rotor slots N r and the number of pole pairs of the stator armature winding are P as such that the following formula is satisfied, a reluctance torque component similar to the synchronous reluctance torque will be generated; （3） After the stator winding is energized with alternating current, the Pas rotating magnetic potential of the stator with opposite poles, after passing through the magnetic conductance wave formed by the stator teeth with the number of teeth Ns When the rotating magnetic field generated after magnetic field modulation has the same number of pole pairs as the rotating magnetic field generated by the rotor alternating current component, that is, when the following formula is satisfied, stator electromagnetic torque will be generated, and the expression is as follows: （4）。 4. The structure of the stator-rotor double-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, wherein The matching relationship between the number of slots and the number of pole pairs of the stator and the rotor is:

5. The structure of the stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, characterized in that The outer contours of the rotor teeth and the rotor yoke are both concentric circular arc structures; The outer contours of the stator teeth and the stator yoke are both concentric circular arc structures; The air gap is between the outer contours of the rotor teeth and the stator teeth.

6. The structure of the stator-rotor double-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, characterized in that The rotor armature winding is a two-phase winding, and adjacent two rotor armature windings are connected to form phase A+, phase A-, phase B+ and phase B- in sequence.

7. The structure of the stator-rotor dual-armature winding multiple electromagnetic torque single-air-gap reluctance motor according to claim 1, characterized in that The stator armature winding is a three-phase winding, and the stator armature windings are connected in sequence to form phase D, phase E and phase F.

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