Bilateral multi-rotor combined multiphase linear motor and fluctuation suppression method thereof

Abstract

The invention relates to a bilateral multi-mover combined multiphase linear motor and a fluctuation suppression method thereof, the multiphase linear motor comprises a stator and a bilateral multi-mover unit, and the stator comprises a primary iron core, a coil and a fixed structural member; each mover unit comprises a first mover and a second mover which are symmetrically arranged on two sides of the stator; each of the first mover and the second mover comprises a permanent magnet array and secondary back iron; the adjacent mover units are arranged according to a set interval, and the interval between the adjacent mover units is set to be a non-integer multiple of the slot pitch of the motor, so that the positioning force fluctuation and the thrust fluctuation between the adjacent mover units are both presented as reverse-phase waves, and the positioning force fluctuation and the thrust fluctuation between the adjacent mover units are both offset. The positioning force fluctuation and the thrust fluctuation of the motor can be reduced, the motor operation is more stable, and the motor motion control combination is more flexible and diversified.

Description

Technical Field

[0001] The present application relates to the technical field of linear motors, and in particular to a multi-phase linear motor with a bilateral multi-motor combination and a method for suppressing fluctuations thereof. Background Art

[0002] A linear motor is a transmission device that converts electrical energy directly into linear motion mechanical energy without any intermediate conversion mechanism. Linear motors are core equipment in the fields of industrial automation, logistics and transportation, maglev trains, and new non-adhesion urban rail vehicles due to their non-adhesion drive, simple structure, and reliable performance.

[0003] In modern production and life, reciprocating servo systems, factory automation, conveying systems, and transportation mostly use permanent magnet synchronous linear motors. Permanent magnet synchronous linear motors have the advantages of simple structure, high efficiency and energy saving, but they generally have end effects, which lead to disadvantages such as large thrust fluctuations, large speed fluctuations, large positioning force fluctuations, and low positioning accuracy, which to a certain extent restrict the development and application of linear motors. Summary of the invention

[0004] Based on this, it is necessary to provide a multi-phase linear motor with a bilateral multi-motor combination and a fluctuation suppression method thereof, which can reduce the thrust fluctuation and positioning force fluctuation of the linear motor, in order to address the above technical problems.

[0005] A multi-phase linear motor with a bilateral multi-motor combination, the multi-phase linear motor comprising:

[0006] A stator and a double-sided structured multi-motor unit, wherein the stator comprises a primary iron core, a coil and a fixed structure; each motor unit comprises a first motor and a second motor symmetrically arranged on both sides of the stator, and the first motor and the second motor both comprise a permanent magnet array and a secondary back iron; adjacent motor units are arranged at a set spacing;

[0007] The step of setting the spacing between adjacent moving sub-units includes:

[0008] A first adjustment parameter is set according to the number of mover units in the multi-phase linear motor; the first adjustment parameter is set to a positive integer greater than or equal to 2 through a second adjustment parameter, the second adjustment parameter is a natural number and the number of mover units is greater than 1;

[0009] According to the product of the ratio of the third adjustment parameter to the first adjustment parameter and the motor slot pitch, the spacing expression between adjacent mover units is set; the third adjustment parameter is a positive integer, and the ratio of the third adjustment parameter to the first adjustment parameter is a non-integer;

[0010] The spacing between adjacent mover units is set by adjusting the values ​​of the second adjustment parameter and the third adjustment parameter in the spacing expression.

[0011] Furthermore, the product of the number of slots and the slot pitch in a multiphase linear motor is equal to the product of the number of poles and the pole pitch, expressed as s×τ s =n×τ n , where s is the number of motor slots, n is the number of motor poles, τ s is the motor slot pitch, τ n is the motor pole pitch.

[0012] Furthermore, the coils in the multi-phase linear motor are arranged with one primary core between them, the number of coils corresponding to the mover poles is s / 2, and the number of pole pairs of the mover poles is n / 2.

[0013] Furthermore, the multi-phase linear motor adopts multi-phase independent winding control.

[0014] Furthermore, different currents are passed through different phases of the multi-phase linear motor, and the passed currents are controlled in an independent manner; wherein the currents passed through different phases are

[0015]

[0016] Among them, I i Represents the current flowing into phase i, I pi is the amplitude of the current flowing into phase i, ω is the angular velocity and ω=2πf=πv / τ n , t is time, v is the running speed of the multi-phase linear motor, is the phase of the current flowing into phase i.

[0017] Furthermore, the phase difference between adjacent phases in a multiphase linear motor is expressed as

[0018] Δθ=2π(n / 2) / (s / 2)=2πn / s.

[0019] Furthermore, the first mover and the second mover in the mover unit of the multi-phase linear motor are bilaterally symmetrically arranged on the left and right sides or the upper and lower sides of the stator.

[0020] Furthermore, the first mover and the second mover in the same mover unit and adjacent mover units are connected via structural members.

[0021] Furthermore, the structural member is a metal member or a non-metal member.

[0022] A method for suppressing fluctuations of a multi-phase linear motor with a bilateral multi-motor combination, the method comprising:

[0023] According to the number of mover units in the multi-phase linear motor, the spacing between adjacent mover units is set to a non-integer multiple of the motor slot pitch, so that the positioning force fluctuation and thrust fluctuation between adjacent mover units both appear as anti-phase waves, and the positioning force fluctuation and thrust fluctuation between adjacent mover units both offset each other.

[0024] Furthermore, the method also includes: the positioning force fluctuation and thrust fluctuation of the mover unit present a periodic distribution with the position change, and the period length is the motor slot pitch τ s .

[0025] The above-mentioned multi-phase linear motor with bilateral multi-motor combination and its fluctuation suppression method have the following technical effects:

[0026] 1. In the multi-phase linear motor with bilateral multi-motor combination, the multi-motor units of the bilateral structure are symmetrically arranged on both sides of the stator. The normal forces of the bilateral movers cancel each other out, and the synthetic normal force of the multi-motor units is close to zero, which reduces the requirements of the motor for the guide rail support and has the advantages of high reliability and long service life.

[0027] 2. The adjacent mover units in the multi-phase linear motor with bilateral multi-motor combination are arranged according to a set spacing, and the spacing between adjacent mover units is set to a non-integer multiple of the motor slot pitch through the number of mover units and adjustment parameters, so that the positioning force fluctuation and thrust fluctuation between adjacent mover units appear as anti-phase waves, the positioning force fluctuation and thrust fluctuation between adjacent mover units offset each other, the positioning force fluctuation and thrust fluctuation of the motor are significantly reduced, the motor runs more smoothly and the motor motion control combination is more flexible and diverse. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 is a front view schematic diagram of a multi-phase linear motor with a bilateral multi-motor combination when the number of the mover units is 2 in one embodiment;

[0029] Figure 2 1 is a side view schematic diagram of a multi-phase linear motor with a bilateral multi-motor combination when the number of the mover units is 2 in one embodiment;

[0030] Figure 3 A schematic diagram of multi-phase independent driving of a multi-phase linear motor with a bilateral multi-motor combination in one embodiment;

[0031] Figure 4 is a front view schematic diagram of a multi-phase linear motor when the number of the mover units is 1 in one embodiment;

[0032] Figure 5 is a side view schematic diagram of a multi-phase linear motor when the number of the mover units is 1 in one embodiment;

[0033] Figure 6Schematic diagram of a positioning force fluctuation curve of a multi-phase linear motor when the number of mover units is 1 in one embodiment;

[0034] Figure 7 Schematic diagram of thrust fluctuation curve of a multi-phase linear motor when the number of mover units is 1 in one embodiment;

[0035] Figure 8 is a schematic diagram of a normal force fluctuation curve of a multi-phase linear motor when the number of mover units is 1 in one embodiment;

[0036] Fig. 9 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is 2τ s , a front view schematic diagram of a multi-phase linear motor;

[0037] Fig.10 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is 2τ s Schematic diagram of the positioning force fluctuation curves of the two moving units of the multi-phase linear motor when ;

[0038] Fig.11 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is 2τ s Schematic diagram of the synthetic positioning force fluctuation curve of the two mover units of the multi-phase linear motor when ;

[0039] Fig.12 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is 2τ s Schematic diagram of thrust fluctuation curves of the two moving units of the multi-phase linear motor when ;

[0040] Fig.13 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is 2τ s Schematic diagram of the synthetic thrust fluctuation curve of the two moving units of the multi-phase linear motor when ;

[0041] Fig.14 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is , a front view schematic diagram of a multi-phase linear motor;

[0042] Fig.15 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is Schematic diagram of the positioning force fluctuation curves of the two moving units of the multi-phase linear motor when ;

[0043] Fig.16In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is Schematic diagram of the synthetic positioning force fluctuation curve of the two mover units of the multi-phase linear motor when ;

[0044] Fig.17 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is Schematic diagram of thrust fluctuation curves of the two moving units of the multi-phase linear motor when ;

[0045] Fig.18 In one embodiment, when the number of the moving subunits is 2 and the spacing between the moving subunits is Schematic diagram of the synthetic thrust fluctuation curve of the two mover units of a multi-phase linear motor when . DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0047] In one embodiment, a multi-phase linear motor with a bilateral multi-motor combination is provided. When the number of the mover units is 2, the front view and the side view of the multi-phase linear motor with a bilateral multi-motor combination are respectively as shown in FIG. Figure 1 and Figure 2 As shown, the multi-phase linear motor comprises:

[0048] A stator and a double-sided structured multi-motor unit, wherein the stator comprises a primary iron core, a coil and a fixed structure; each motor unit comprises a first motor and a second motor symmetrically arranged on both sides of the stator, and the first motor and the second motor both comprise a permanent magnet array and a secondary back iron; adjacent motor units are arranged at a set spacing;

[0049] The step of setting the spacing between adjacent moving sub-units includes:

[0050] A first adjustment parameter is set according to the number of mover units in the multi-phase linear motor; the first adjustment parameter is set to a positive integer greater than or equal to 2 through a second adjustment parameter, the second adjustment parameter is a natural number and the number of mover units is greater than 1;

[0051] According to the product of the ratio of the third adjustment parameter to the first adjustment parameter and the motor slot pitch, the spacing expression between adjacent mover units is set; the third adjustment parameter is a positive integer, and the ratio of the third adjustment parameter to the first adjustment parameter is a non-integer;

[0052] By adjusting the values ​​of the second adjustment parameter and the third adjustment parameter in the spacing expression, the spacing between adjacent moving subunits is set. Specifically, the spacing expression is: m is the number of the moving subunits and m>1, a is the third adjustment parameter and is a positive integer, b is the second adjustment parameter and is a natural number, mb is the first adjustment parameter and mb is a positive integer greater than or equal to 2, τ s is the motor slot pitch. By adjusting the values ​​of the second adjustment parameter b and the third adjustment parameter a in the spacing expression, the spacing between adjacent mover units can be set to a non-integer multiple of the motor slot pitch, so that the positioning force fluctuation and thrust fluctuation between adjacent mover units are both anti-phase waves, the positioning force fluctuation and thrust fluctuation between adjacent mover units are offset each other, the positioning force fluctuation and thrust fluctuation of the motor are significantly reduced, and the motor runs more smoothly.

[0053] Specifically, the spacing between adjacent mover units can be set as:

[0054] When m=2, the spacing can be set as:

[0055] When m=3, the spacing can be set as:

[0056] When m=3, the spacing can be set as:

[0057] When m=4, the spacing can be set as:

[0058] When m=4, the spacing can be set as:

[0059] When m=4, the spacing can be set as:

[0060] Furthermore, the product of the number of slots and the slot pitch in a multiphase linear motor is equal to the product of the number of poles and the pole pitch, expressed as s×τ s =n×τ n , where s is the number of motor slots, n is the number of motor poles, τ s is the motor slot pitch, τ n is the motor pole pitch.

[0061] Furthermore, the coils in the multi-phase linear motor are arranged with one primary core between them, the number of coils corresponding to the mover poles is s / 2, and the number of pole pairs of the mover poles is n / 2.

[0062] Furthermore, the multi-phase linear motor adopts multi-phase independent winding control, and the multi-phase independent drive of the multi-phase linear motor is as follows Figure 3As shown. It can be understood that usually the number of slots and the number of poles of the motor adopts a fractional slot combination to reduce the fluctuation of the motor cogging force, such as 12 slots and 10 poles, 9 slots and 7 poles, 6 slots and 5 poles, 5 slots and 4 poles, 8 slots and 7 poles, etc. However, since the present application adopts multi-phase independent winding control, the number of slots or coils does not have to be a multiple of 3, which is different from the conventional three-phase motor.

[0063] Furthermore, different currents are passed through different phases of the multi-phase linear motor, and the passed currents are controlled in an independent manner; wherein the currents passed through different phases are

[0064]

[0065] Where Ii represents the current flowing into phase i, I pi is the amplitude of the current flowing into phase i, ω is the angular velocity and ω=2πf=πv / τ n , t is time, v is the running speed of the multi-phase linear motor, is the phase of the current flowing into phase i.

[0066] Furthermore, the phase difference between adjacent phases in a multiphase linear motor is expressed as

[0067] Δθ=2π(n / 2) / (s / 2)=2πn / s.

[0068] Specifically, when s=12, n=10, that is, 12 slots and 10 poles, the number of coils corresponding to the rotor poles is 5. At this time, the expression of the current flowing through all phases in the multi-phase linear motor is

[0069]

[0070] Where θ0 represents the initial phase angle.

[0071] Furthermore, the first mover and the second mover in the mover unit of the multi-phase linear motor are bilaterally symmetrically arranged on the left and right sides or the upper and lower sides of the stator.

[0072] Furthermore, the first mover and the second mover in the same mover unit and adjacent mover units are connected via structural members.

[0073] Furthermore, the structural member is a metal member or a non-metal member.

[0074] A method for suppressing fluctuations of a multi-phase linear motor with a bilateral multi-motor combination, the method comprising:

[0075] According to the number of mover units in the multi-phase linear motor, the spacing between adjacent mover units is set to a non-integer multiple of the motor slot pitch, so that the positioning force fluctuation and thrust fluctuation between adjacent mover units both appear as anti-phase waves, and the positioning force fluctuation and thrust fluctuation between adjacent mover units both offset each other.

[0076] Furthermore, the method also includes: the positioning force fluctuation and thrust fluctuation of the mover unit present a periodic distribution with the position change, and the period length is the motor slot pitch τ s .

[0077] In a specific embodiment, in order to further illustrate the beneficial effects of a multi-phase linear motor with a bilateral multi-motor combination provided by the present application, an experimental verification is also carried out, and the specific steps include:

[0078] The first experimental condition is set as follows: the number of the moving unit is 1. Under this condition, the front view and side view of the multiphase linear motor are as follows: Figure 4 and Figure 5 As shown. During the operation of the motor, the motor positioning force fluctuation curve is drawn as shown Figure 6 As shown, the motor thrust fluctuation curve is drawn as Figure 7 As shown, the motor normal force fluctuation curve is drawn as Figure 8 As shown. Figure 6 , Figure 7 and Figure 8 It can be seen that under the first experimental condition, the positioning force fluctuation of the motor is 2.5N, the thrust fluctuation is 3.4N, the rated thrust is 79N, and the thrust fluctuation ratio is 4.3%. At this time, although the normal force of the motor is close to zero, there is still a certain thrust fluctuation.

[0079] The second experimental condition is set as follows: the number of motor units is 2, and the spacing between the motor units is 2τ s The front view of the multiphase linear motor under this condition is as follows Fig. 9 As shown in Figure 2. During the operation of the motor, the positioning force fluctuation curves of the two moving units are shown in Figure 2. Fig.10 As shown, the synthetic positioning force fluctuation curve of the two actuator units is drawn as Fig.11 As shown, the thrust fluctuation curves of the two moving units are drawn as follows Fig.12 As shown, the synthetic thrust fluctuation curve of the two moving units is drawn as Fig.13 As shown. Figures 10 to 13 As shown in the figure, under the second experimental condition, the positioning force fluctuation of the two moving units combined is 5.0N, the thrust fluctuation is 6.8N, the synthetic thrust is 158N, and the thrust fluctuation ratio is 4.3%. At this time, compared with the first experimental condition, although the thrust of the motor operation has increased significantly, the thrust fluctuation and positioning force fluctuation have also increased.

[0080] The third experimental condition is set as follows: the number of mover units is 2, and the spacing between the mover units is The front view of the multiphase linear motor under this condition is as follows Fig.14 As shown in Figure 2. During the operation of the motor, the positioning force fluctuation curves of the two moving units are shown in Figure 2. Fig.15 As shown, the synthetic positioning force fluctuation curve of the two actuator units is drawn as Fig.16 As shown, the thrust fluctuation curves of the two moving units are drawn as follows Fig.17 As shown, the synthetic thrust fluctuation curve of the two moving units is drawn as Fig.18 As shown. Figures 15 to 18 As shown, under the third experimental condition, the positioning force fluctuation of the two mover units combined is 1.6N, the thrust fluctuation is 2.7N, the synthetic thrust is 158N, and the thrust fluctuation ratio is 1.7%, which is significantly reduced compared with the thrust fluctuation ratio of 4.3% in the first and second experimental conditions.

[0081] Therefore, compared with the first and second experimental conditions, in the third experimental condition, according to the multi-phase linear motor with a bilateral multi-motor combination provided by the present application, the thrust of the motor operation is increased because the multi-motor unit combination of the bilateral structure in the multi-phase linear motor is arranged on both sides of the stator. And the spacing between adjacent motor units is set to a non-integer multiple of the motor slot pitch, so that the positioning force fluctuation and thrust fluctuation between adjacent motor units are both presented as anti-phase waves, such as Fig.15 and Fig.17 As shown, the positioning force fluctuations and thrust fluctuations between adjacent mover units offset each other, so that the total positioning force fluctuations and thrust fluctuations of the motor are reduced, and the motor runs more smoothly.

[0082] The technical features of the above embodiments may 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.

[0083] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A multi-phase linear motor with a bilateral multi-motor combination, characterized in that: The multi-phase linear motor comprises: A stator and a double-sided structured multi-motor unit, wherein the stator comprises a primary iron core, a coil and a fixed structure; each motor unit comprises a first motor and a second motor which are symmetrically arranged on both sides of the stator, and the first motor and the second motor both comprise a permanent magnet array and a secondary back iron; adjacent motor units are arranged at a set spacing; The step of setting the spacing between adjacent moving sub-units includes: A first adjustment parameter is set according to the number of mover units in the multi-phase linear motor; the first adjustment parameter is set to a positive integer greater than or equal to 2 through a second adjustment parameter, the second adjustment parameter is a natural number and the number of mover units is greater than 1; According to the product of the ratio of the third adjustment parameter to the first adjustment parameter and the motor slot pitch, the spacing expression between adjacent mover units is set; the third adjustment parameter is a positive integer, and the ratio of the third adjustment parameter to the first adjustment parameter is a non-integer; The distance between adjacent mover units is set by adjusting the values ​​of the second adjustment parameter and the third adjustment parameter in the distance expression.

2. The multi-phase linear motor with bilateral multi-motor combination according to claim 1, characterized in that: The product of the number of slots and the slot pitch in the multiphase linear motor is equal to the product of the number of poles and the pole pitch, which is expressed as s×τ s =n×τ n , where s is the number of motor slots, n is the number of motor poles, τ s is the motor slot pitch, τ n is the motor pole pitch.

3. The multi-phase linear motor with double-sided multi-motor combination according to claim 2, characterized in that: The coils in the multi-phase linear motor are arranged with one primary iron core in between, the number of coils corresponding to the mover magnetic poles is s / 2, and the number of pole pairs of the mover magnetic poles is n / 2.

4. The multi-phase linear motor with double-sided multi-motor combination according to claim 2, characterized in that: The multi-phase linear motor adopts multi-phase independent winding control.

5. The multi-phase linear motor with double-sided multi-motor combination according to claim 2, characterized in that: Different currents are passed through different phases of the multi-phase linear motor, and the currents passed through are controlled in an independent manner; wherein the currents passed through different phases are Among them, I i Represents the current flowing into phase i, I pi is the amplitude of the current flowing into phase i, ω is the angular velocity and ω=2πf=πv / τ n , t is time, v is the running speed of the multi-phase linear motor, is the phase of the current flowing into phase i.

6. The multi-phase linear motor with double-sided multi-motor combination according to claim 2, characterized in that: The phase difference between adjacent phases in the multi-phase linear motor is expressed as Δθ=2π(n / 2) / (s / 2)=2πn / s.

7. The multi-phase linear motor with double-sided multi-motor combination according to claim 1, characterized in that: The first mover and the second mover in the mover unit are bilaterally symmetrically arranged on the left and right sides or the upper and lower sides of the stator.

8. The multi-phase linear motor with double-sided multi-motor combination according to claim 1, characterized in that: The first mover and the second mover in the same mover unit and adjacent mover units are connected via structural members.

9. The multi-phase linear motor with double-sided multi-motor combination according to claim 8, characterized in that: The structural member is a metal member or a non-metal member.

10. A method for suppressing fluctuations of a multi-phase linear motor with a bilateral multi-motor combination according to any one of claims 1 to 9, characterized in that: The method comprises: According to the number of mover units in the multi-phase linear motor, the spacing between adjacent mover units is set to a non-integer multiple of the motor slot pitch, so that the positioning force fluctuation and thrust fluctuation between adjacent mover units both appear as anti-phase waves, and the positioning force fluctuation and thrust fluctuation between adjacent mover units both offset each other.

11. The method for suppressing fluctuations of a multi-phase linear motor with a bilateral multi-motor combination according to claim 10, characterized in that: The method further includes: the positioning force fluctuation and thrust fluctuation of the mover unit present a periodic distribution with position change, and the period length is the motor slot pitch τ s .

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