阅读说明：本技术 旋转式变压器 (Rotary transformer ) 是由 葛笑 万佳 于 2018-06-29 设计创作，主要内容包括：本发明提出了一种旋转式变压器,包括：定子,包括定子铁芯以及绕设在定子铁芯上的输入绕组与输出绕组,定子铁芯的内侧壁上开设多个定子槽,多个定子槽沿周向分布,并分别使定子铁芯的两个端面导通,以使任意两个相邻的定子槽之间形成定子齿,定子齿包括用于绕设输入绕组的定子主齿以及用于绕设输出绕组的定子副齿；转子,包括转子铁芯,转子铁芯与定子铁芯相互套设,其中,定子主齿与定子负齿之间的比值为k,0.7<k<1。通过本发明的技术方案,以通过减小实际的极弧长度消除三次谐波向量的漂移现象,最终达到提高旋转式变压器的转子位置精度的目的。(The invention provides a rotary transformer, comprising: the stator comprises a stator core, an input winding and an output winding, wherein the input winding and the output winding are wound on the stator core, a plurality of stator slots are formed in the inner side wall of the stator core and are distributed along the circumferential direction, two end faces of the stator core are respectively conducted, so that stator teeth are formed between any two adjacent stator slots, and each stator tooth comprises a stator main tooth for winding the input winding and a stator auxiliary tooth for winding the output winding; the rotor, including rotor core, rotor core and stator core overlap each other to be established, and wherein, the ratio between stator owner tooth and the stator minus tooth is k, and 0.7< k < 1. According to the technical scheme of the invention, the drift phenomenon of the third harmonic vector is eliminated by reducing the actual pole arc length, and the aim of improving the rotor position precision of the rotary transformer is finally achieved.)

1. A rotary transformer, comprising:

the stator comprises a stator core, an input winding and an output winding, wherein the input winding and the output winding are wound on the stator core, a plurality of stator slots are formed in the inner side wall of the stator core and are distributed along the circumferential direction, two end faces of the stator core are respectively conducted, so that stator teeth are formed between any two adjacent stator slots, and each stator tooth comprises a stator main tooth used for winding the input winding and a stator auxiliary tooth used for winding the output winding;

a rotor including a rotor core, the rotor core and the stator core being sleeved with each other,

wherein the ratio between the stator main teeth and the stator negative teeth is k, 0.7< k < 1.

2. The rotary transformer of claim 1,

the input winding comprises an excitation winding;

the output winding comprises a sine winding and a cosine winding,

the stator auxiliary teeth are arranged between any two adjacent excitation windings at intervals so as to be wound on the sine winding and the cosine winding respectively, two sides of one of the two excitation windings are wound on the sine winding, and the other two sides of the two excitation windings are wound on the cosine winding.

3. The rotary transformer of claim 2,

the number of turns of the coil of the excitation winding on each stator main tooth is the same;

and the number of turns of the sine winding is the same as that of the cosine winding.

4. The rotary transformer of claim 3,

an ideal coil electrical angle of the excitation winding of each stator main tooth, an ideal coil electrical angle of the sine winding on each stator secondary tooth, and an ideal coil electrical angle of the cosine winding on each stator secondary tooth are each β ═ P × 360 °/S,

and determining the output potential of the rotary transformer in one rotation period according to the ideal coil electrical angle, wherein P is the number of pole pairs of a rotor of the rotary transformer, S is the number of the stator teeth, and the magnetic field of the excitation winding returns to and closes the stator main teeth after passing through the adjacent stator auxiliary teeth after being triggered by the stator main teeth.

5. Rotary transformer according to claim 4,

the number of the stator teeth is integral multiple of 12.

6. The rotary transformer of claim 5,

when the number of the stator teeth is 24 and the number of the rotor pole pairs of the rotary transformer is 2, the ratio between the stator main teeth and the stator negative teeth is 0.8< k < 0.85.

7. The rotary transformer of claim 3,

the width of the stator main teeth is 5 mm;

the width of the stator secondary tooth is 6 mm.

8. The rotary transformer of claim 1,

the outer profile of the rotor core is configured to produce sinusoidal track air gap permeance variation.

9. The rotary transformer of claim 1,

and a limiting groove is formed in the inner side wall of the shaft hole of the rotor core.

10. Rotary transformer according to any one of claims 1 to 9,

the stator core is formed by a plurality of silicon steel sheets in an axial superposition structure along the rotating shaft of the rotor;

the rotor core is formed by a plurality of silicon steel sheets which are stacked along the axial direction of the rotating shaft,

the end faces of the two ends of the rotor core respectively protrude out of the end faces of the two ends of the stator core along the axial direction.

Technical Field

The invention relates to the field of compressors, in particular to a rotary transformer.

Background

The rotary transformer is an electromagnetic sensor, also called as synchronous resolver, used for measuring the angular displacement and angular speed of the rotating shaft of a rotating object, and composed of a stator and a rotor, wherein the stator winding is used as the round edge of the transformer and receives the excitation voltage, the rotor winding is used as the secondary edge of the transformer, the induced voltage is obtained through electromagnetic coupling, the size of the output voltage changes along with the angular displacement of the rotor because the primary edge and the secondary edge of the transformer are selected to change along with the relative position of the angular displacement of the rotor, and the voltage amplitude of the output winding and the rotor rotation angle are in sine and cosine function relation.

The salient pole type rotary transformer is widely applied to occasions with high safety performance requirements, such as automobile motors, due to the fact that the salient pole type rotary transformer is simple to manufacture, high in stability and good in temperature resistance. In the related art, as shown in fig. 1 to 6, since the winding input winding and the winding output winding have the same tooth width of the stator teeth, there are the following disadvantages:

the rotor error is large, and the position accuracy of the rotary transformer is not high.

Disclosure of Invention

In order to solve at least one of the above technical problems, an object of the present invention is to provide a rotary transformer.

In order to achieve the above object, an embodiment of the present invention provides a rotary transformer, including: the stator comprises a stator core, an input winding and an output winding, wherein the input winding and the output winding are wound on the stator core, a plurality of stator slots are formed in the inner side wall of the stator core and are distributed along the circumferential direction, two end faces of the stator core are respectively conducted, so that stator teeth are formed between any two adjacent stator slots, and each stator tooth comprises a stator main tooth for winding the input winding and a stator auxiliary tooth for winding the output winding; the rotor, including rotor core, rotor core and stator core overlap each other to be established, and wherein, the ratio between stator owner tooth and the stator minus tooth is k, and 0.7< k < 1.

In the technical scheme, the rotary transformer is a reluctance type rotary transformer, an input winding and an output winding (comprising a sine winding and a cosine winding) are wound on stator teeth of a stator core according to a specified winding mode, the stator teeth are divided into a stator main tooth and a stator auxiliary tooth according to the wound input winding or output winding, stator excitation is realized through the input winding, a changed potential signal is output through the output winding, an excitation magnetic field is generated after the input winding is electrified, and the excitation magnetic field passes through the stator auxiliary tooth of an adjacent output winding from the stator main tooth, so that the actually generated pole arc length of the excitation magnetic field is larger than the tooth width of the stator main tooth of the corresponding excitation winding, the third harmonic vector of the induced potential of the input winding has a drift phenomenon, the measurement precision of the rotary transformer is realized by setting the width of the stator main tooth to be smaller than the width of the stator main tooth, the drift phenomenon of the third harmonic vector is eliminated by reducing the actual pole arc length, and the purpose of improving the rotor position precision of the rotary transformer is finally achieved.

In addition, the rotary transformer in the above technical solution provided by the present invention may further have the following additional technical features:

in the above technical solution, preferably, the input winding includes an excitation winding; the output winding comprises a sine winding and a cosine winding, wherein two stator auxiliary teeth are arranged between any two adjacent excitation windings at intervals so as to respectively wind the sine winding and the cosine winding, and the sine winding is wound on two sides of one of the two excitation windings and the cosine winding is wound on two sides of the other excitation winding.

In the technical scheme, two stator auxiliary teeth are arranged between any two adjacent excitation windings at intervals to respectively wind a sine winding and a cosine winding, so that the excitation windings, the sine winding and the cosine winding are distributed at intervals along the circumferential direction, and stator excitation is realized through the excitation windings.

In addition, according to winding different windings, a plurality of stator teeth distributed in the circumferential direction can be divided into stator main teeth and stator auxiliary teeth, two stator auxiliary teeth are arranged between the two stator main teeth at intervals, specifically, an input winding and an output winding can be divided into a plurality of winding units, the winding units are connected end to end along the circumferential direction to complete winding, and in one winding unit, an excitation winding, a sine winding, a cosine winding, an excitation winding, a cosine winding and a sine winding are sequentially included along the counterclockwise direction, or the excitation winding, the cosine winding, the sine winding, the excitation winding, the sine winding and the cosine winding are sequentially included along the counterclockwise direction.

Specifically, the stator excitation winding of the rotary transformer is alternately distributed at intervals of two stator auxiliary teeth, an excitation magnetic field generated by electrifying the excitation winding is emitted from a stator main tooth, passes through adjacent left and right stator auxiliary teeth, passes through a rotor iron core and finally returns to the stator main tooth, if the width of the stator main tooth is the same as that of the stator auxiliary teeth, the actual pole arc width generated by the excitation magnetic field is larger than the ideal pole arc width, so that the magnetic field angle is deviated, the output induced potential of the sine and cosine windings is led into larger third harmonic, the stator main tooth width is limited to be smaller than the stator auxiliary tooth width, and the ratio between the stator main tooth width and the stator auxiliary tooth width is k, wherein k is 0.7< k <1, so that the magnetic field angle deviation caused by the actual pole arc width generated by the excitation magnetic field can be effectively corrected, and the third harmonic in the output induced potential of the sine and cosine windings of the, the rotor position accuracy of the rotary transformer is improved.

In any of the above technical solutions, preferably, the number of turns of the excitation winding on each stator main tooth is the same; the number of turns of the sine winding is the same as that of the cosine winding.

In the technical scheme, the number of turns of the coil of the excitation winding on each stator main tooth is limited to be the same so as to uniformly generate stator excitation, thereby realizing uniform rotation of the rotor, and the number of turns of the coil of the sine winding is limited to be the same as that of the coil of the cosine winding, so that the output potential of the sine winding and the output potential of the cosine winding only have phase difference, thereby ensuring accurate measurement of angular displacement and angular speed of the rotating shaft.

In any of the above technical solutions, preferably, an ideal coil electrical angle of the excitation winding of each stator main tooth, an ideal coil electrical angle of the sine winding of each stator secondary tooth, and an ideal coil electrical angle of the cosine winding of each stator secondary tooth are β ═ P × 360 °/S, where an output potential of the rotary transformer in one rotation cycle is determined according to the ideal coil electrical angles, P is a number of pairs of rotor poles of the rotary transformer, S is a number of stator teeth, and a magnetic field of the excitation winding is triggered from the stator main tooth, passes through the adjacent stator secondary tooth, and returns to and closes the stator main tooth.

In the technical scheme, the ideal coil electrical angle of each winding coil is determined according to the number of the rotor pole pairs and the number of the stator teeth of the rotary transformer, so that the corresponding ideal pole arc length is determined, the specific drift amount is determined according to the difference value between the ideal pole arc length and the actual pole arc length, the optimal ratio k between the stator main teeth and the stator negative teeth can be determined according to the specific drift amount, and the purpose of eliminating the drift amount of the induced potential is finally achieved.

In any of the above solutions, the number of stator teeth is preferably an integer multiple of 12.

In the technical scheme, the number of the stator teeth is limited to be an integral multiple of 12, so that the number of the excitation windings is even, and the excitation windings, the sine windings and the cosine windings are regularly arranged, thereby reducing multiple harmonics except a primary fundamental wave to the maximum extent and ensuring that the error of rotor measurement is not too large.

In any of the above solutions, preferably, when the number of stator teeth is 24 and the number of pairs of rotor poles of the rotary transformer is 2, the ratio between the stator main teeth and the stator negative teeth is 0.8< k < 0.85.

In the technical scheme, as a specific setting mode, the number of stator teeth is 24, the number of rotor pole pairs of the rotary transformer is 2, the windings are circumferentially arranged in a mode of an excitation winding 1, a sine winding 2, a cosine winding 3, an excitation winding 4, a cosine winding 5, a sine winding 6, an excitation winding 7, a sine winding 8, a cosine winding 9, an excitation winding 10, a cosine winding 11, a sine winding 12, an excitation winding 13, a sine winding 14, a cosine winding 15, an excitation winding 16, a cosine winding 17, a sine winding 18, an excitation winding 19, a sine winding 20, a cosine winding 21, an excitation winding 22, a cosine winding 23 and a sine winding 24, and in the structural form, the position measurement precision of the rotary transformer can be further improved by that the ratio between the main teeth and the negative teeth of the stator is 0.8< k < 0.85.

In any of the above technical solutions, preferably, the width of the stator main teeth is 5 mm; the width of the stator secondary teeth is 6 mm.

In the technical scheme, as a preferable arrangement mode, the width of the main teeth of the stator is 5 mm; the width of the stator secondary tooth is 6mm, namely k is 0.83, so that the third harmonic of the output potential can be reduced to the maximum extent, and the rotor detection precision is correspondingly improved.

In any of the above solutions, preferably, the outer profile of the rotor core is configured to produce sinusoidal track air gap permeance variation.

In any of the above technical solutions, preferably, the inner side wall of the shaft hole of the rotor core is provided with a limit groove; the outer side wall of the rotating shaft is provided with a limiting rib matched with the limiting groove.

In this technical scheme, through having seted up the spacing groove on the inside wall in rotor core's shaft hole, the corresponding be provided with on the lateral wall of pivot with spacing groove complex spacing muscle to through the interference fit between rotor core and the pivot, realize under the effect of excitation magnetic field, it is rotatory to drive the pivot by rotor core, in order to realize the measurement to the rotation angle isoparametric of rotor.

In any of the above technical solutions, preferably, the stator core is formed by stacking a plurality of silicon steel sheets in an axial direction of the rotating shaft; the rotor core is formed by a plurality of silicon steel sheets along the axial superposition structure of the rotating shaft, wherein the end faces of the two ends of the rotor core respectively protrude out of the end faces of the two ends of the stator core along the axial direction.

Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 is a schematic cross-sectional view illustrating a rotary transformer in the related art;

fig. 2 shows a partially developed schematic view of the stator of the rotary transformer of fig. 1;

FIG. 3 shows a potential vector diagram of the primary fundamental of the rotary transformer of FIG. 1;

FIG. 4 shows a potential vector diagram of the second harmonic of the rotary transformer of FIG. 1;

FIG. 5 shows a potential vector diagram of the third harmonic of the rotary transformer of FIG. 1;

FIG. 6 shows a vector diagram of potential drift of the rotary transformer of FIG. 1;

fig. 7 shows a schematic cross-sectional structure of a rotary transformer according to an embodiment of the present invention;

fig. 8 shows a partially developed schematic view of the stator of the rotary transformer of fig. 7.

Wherein, the correspondence between the reference numbers and the part names in fig. 7 and 8 is:

1 rotary transformer, 10 stators, 102 stator cores, 104 excitation windings, 106 sine windings, 108 cosine windings and 20 rotors.

Detailed Description

In order that the above objects, features and advantages of the present invention can be more clearly understood, a more particular description of the invention will be rendered by reference to the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

As shown in fig. 1, in the prior art, the number of stator teeth is 24, the tooth widths of the stator main teeth and the stator auxiliary teeth are the same, the number of rotor pole pairs of the rotary transformer is 2, and the windings are arranged in the circumferential direction in a manner of an excitation winding 1, a sine winding 2, a cosine winding 3, an excitation winding 4, a cosine winding 5, a sine winding 6, an excitation winding 7, a sine winding 8, a cosine winding 9, an excitation winding 10, a cosine winding 11, a sine winding 12, an excitation winding 13, a sine winding 14, a cosine winding 15, an excitation winding 16, a cosine winding 17, a sine winding 18, an excitation winding 19, a sine winding 20, a cosine winding 21, an excitation winding 22, a cosine winding 23, and a sine winding 24.

Wherein, the difference between the excitation winding 1 and the excitation winding 7 is 6 stator teeth, and the electrical angle between the two excitation windings is as follows: α is 6 × β is 180 °.

A sine winding 24 and a sine winding 2 are wound on two adjacent sides of the excitation winding 1, and the winding direction is positive; the electrical angle of the primary fundamental wave of the induced potential of the sinusoidal winding 24 relative to the exciting winding 1 is-30 degrees, and the electrical angle of the primary fundamental wave of the induced potential of the sinusoidal winding 2 relative to the exciting winding 1 is 30 degrees; the electrical angle of the induction potential second harmonic of the sinusoidal winding 24 relative to the exciting winding 1 is-60 degrees, and the electrical angle of the induction potential second harmonic of the sinusoidal winding 2 relative to the exciting winding 1 is 60 degrees; the electrical angle of the third harmonic of the induced potential of the sinusoidal winding 24 relative to the exciting winding 1 is-90 degrees, and the electrical angle of the third harmonic of the induced potential of the sinusoidal winding 2 relative to the exciting winding is 90 degrees.

A sine winding 6 and a sine winding 8 are wound on two adjacent sides of the excitation winding 7, and the winding direction is negative; the electrical angle of the primary fundamental wave of the induced potential of the sinusoidal winding 6 with respect to the exciting winding 7 is-150 °, (30 ° +180 °), and the electrical angle of the primary fundamental wave of the induced potential of the sinusoidal winding 2 with respect to the exciting winding 7 is-150 °, (210 ° +180 °); the electrical angle of the induction potential second harmonic of the sinusoidal winding 6 relative to the exciting winding 7 is 150 ° × 2 ═ 300 ° — -60 °, and the electrical angle of the induction potential second harmonic of the sinusoidal winding 2 relative to the exciting winding 7 is 210 ° × 2 ═ 420 ° — -60 °; the electrical angle of the induced potential third harmonic of the sinusoidal winding 6 relative to the exciting winding 7 is 150 ° × 3 ═ 450 ° × 90 °, and the electrical angle of the induced potential third harmonic of the sinusoidal winding 2 relative to the exciting winding 7 is 210 ° × 3 ═ 630 ° × -90 °.

As shown in fig. 3, it can be seen from the vector diagram that, in one electrical cycle, the primary fundamental wave of the sinusoidal winding is vector superposition of four coils 24, 2, 6, 8, as shown in fig. 4, the four coils of the second harmonic of the sinusoidal winding cancel to zero, and as shown in fig. 5, the four coil induced potentials of the third harmonic of the sinusoidal winding also cancel each other.

Actually, as shown in fig. 2, since the tooth widths of the stator main tooth and the stator auxiliary tooth are the same, and the ideal pole arc width is equal to the stator tooth width of the excitation winding, since the magnetic field of the adjacent excitation winding is emitted by the stator tooth of the excitation winding, and passes through the stator teeth without the excitation winding on the adjacent two sides, the pole arc width emitted by the actual excitation magnetic field is greater than the stator tooth width of the excitation winding, so that the induced potential of the sinusoidal winding has a deviation Δ β, and the third harmonic vector of the induced potential of the sinusoidal winding has a deviation, as shown in fig. 6, the induced potentials of the four coils of the third harmonic of the sinusoidal winding cannot cancel each other, and there is a component.

In order to reduce or eliminate the component of the third-order induced potential of the sinusoidal winding, the tooth width of the main tooth of the stator where the exciting winding is located is reduced, so that the actual pole arc width of the main tooth is reduced, the deviation delta beta is eliminated, the third-order harmonic component introduced into the middle winding structure can be weakened, the sine property of the output potential of the rotary transformer is increased, and the position angle detection precision of the rotary transformer is improved.

Rotary transformers according to some embodiments of the present invention are described below with reference to fig. 7 and 8 to further illustrate the cancellation offset Δ β.

As shown in fig. 7 and 8, the rotary transformer 1 according to the embodiment of the present invention includes: the stator 10 comprises a stator core 102, and an input winding and an output winding wound on the stator core 102, wherein a plurality of stator slots are formed in the inner side wall of the stator core 102, the plurality of stator slots are distributed along the circumferential direction, and two end faces of the stator core 102 are respectively conducted, so that a stator tooth is formed between any two adjacent stator slots, and the stator tooth comprises a stator main tooth wound with the input winding and a stator auxiliary tooth wound with the output winding; the rotor 20 comprises a rotor core, the rotor core and the stator core 102 are sleeved with each other, wherein the ratio of the main teeth of the stator to the negative teeth of the stator 10 is k, and k is more than 0.7 and less than 1.

In this embodiment, the rotary transformer 1 is a reluctance type rotary transformer 1, an input winding and an output winding (including a sine winding 106 and a cosine winding 108) are wound on stator teeth of a stator core 102 according to a specified winding manner, the stator teeth are divided into a stator main tooth and a stator auxiliary tooth according to whether the input winding or the output winding is wound, excitation of a stator 10 is realized through the input winding, a varying potential signal is output through the output winding, an excitation magnetic field is generated after the input winding is energized, and the excitation magnetic field passes through the stator auxiliary tooth of an adjacent output winding from the stator main tooth, so that the pole arc length of the actually generated excitation magnetic field is larger than the tooth width of the corresponding stator main tooth of the excitation winding 104, a shift phenomenon occurs in a third harmonic vector of the induced potential of the input winding, and the accuracy of the rotary transformer 1 is improved by setting the width of the stator main tooth to be smaller than the width of the stator main tooth, so as to eliminate the drift phenomenon of the third harmonic vector by reducing the actual pole arc length, and finally achieve the purpose of improving the position precision of the rotor 20 of the rotary transformer 1.

In addition, the rotary transformer 1 in the above embodiment of the present invention may further have the following additional technical features:

in the above-described embodiment, preferably, the input winding includes the excitation winding 104; the output windings comprise sine windings 106 and cosine windings 108, wherein two stator auxiliary teeth are arranged between any two adjacent excitation windings 104 at intervals so as to respectively wind the sine windings 106 and the cosine windings 108, and the sine windings 106 are wound on two sides of one of the two excitation windings 104 and the cosine windings 108 are wound on two sides of the other one of the two excitation windings.

In this embodiment, two stator secondary teeth are arranged at intervals between any two adjacent excitation windings 104 to respectively wind the sine winding 106 and the cosine winding 108, so that the excitation windings 104, the sine winding 106 and the cosine winding 108 are circumferentially distributed at intervals to realize excitation of the stator 10 through the excitation windings 104.

In addition, according to winding different windings, a plurality of stator teeth distributed in the circumferential direction can be divided into a stator main tooth and a stator auxiliary tooth, two stator auxiliary teeth are arranged between the two stator main teeth at intervals, specifically, an input winding and an output winding can be divided into a plurality of winding units, the plurality of winding units are connected end to end along the circumferential direction to complete winding, and in one winding unit, the excitation winding 104, the sine winding 106, the cosine winding 108, the excitation winding 104, the cosine winding 108 and the sine winding 106 are sequentially included along the counterclockwise direction, or the excitation winding 104, the cosine winding 108, the sine winding 106, the excitation winding 104, the sine winding 106 and the cosine winding 108 are sequentially included along the counterclockwise direction.

Specifically, the excitation winding 104 of the stator 10 of the rotary transformer 1 is alternately distributed at intervals of two stator secondary teeth, the excitation magnetic field generated by the energization of the excitation winding 104 is emitted from the stator main teeth, passes through the adjacent left and right stator secondary teeth, passes through the rotor core, and finally returns to the stator main teeth, if the width of the stator main teeth is the same as that of the stator secondary teeth, the actual pole arc width generated by the excitation magnetic field is larger than the ideal pole arc width, so that the magnetic field angle is deviated, the output induced potential of the sine and cosine windings 108 is led into larger third harmonic, the stator main teeth width is limited to be smaller than the stator secondary teeth width, and the ratio between the stator main teeth width and the stator secondary teeth is k, 0.7< k <1, the magnetic field angle deviation caused by the actual pole arc width generated by the excitation magnetic field can be effectively corrected, and the third harmonic in the output induced potential of the sine and cosine windings 108 of the rotary transformer 1, the positional accuracy of the rotor 20 of the rotary transformer 1 is improved.

In any of the above embodiments, it is preferable that the number of coil turns of the field winding 104 on each stator main tooth is the same; the number of coil turns of the sine winding 106 is the same as the number of coil turns of the cosine winding 108.

In the embodiment, the number of turns of the coil of the excitation winding 104 on each main tooth of the stator is limited to be the same so as to uniformly generate excitation of the stator 10, thereby realizing uniform rotation of the rotor 20, and the number of turns of the coil of the sine winding 106 is limited to be the same as that of the coil of the cosine winding 108, so that the output potential of the sine winding 106 and the output potential of the cosine winding 108 only have a difference in phase, thereby ensuring accurate measurement of angular displacement and angular velocity of the rotating shaft.

In any of the above embodiments, preferably, the ideal coil electrical angle of the excitation winding 104 of each stator main tooth, the ideal coil electrical angle of the sine winding 106 of each stator secondary tooth, and the ideal coil electrical angle of the cosine winding 108 of each stator secondary tooth are β ═ P × 360 °/S, where the output potential of the rotary transformer 1 in one rotation cycle is determined according to the ideal coil electrical angles, P is the number of pole pairs of the rotor 20 of the rotary transformer 1, and S is the number of stator teeth, and after the magnetic field of the excitation winding 104 is triggered from the stator main tooth, the magnetic field returns to and closes the stator main tooth after passing through the adjacent stator secondary tooth.

In this embodiment, the ideal coil electrical angle of each winding coil is determined according to the number of pole pairs of the rotor 20 and the number of stator teeth of the rotary transformer 1, so as to determine the corresponding ideal pole arc length, and to determine the specific drift amount according to the difference between the ideal pole arc length and the actual pole arc length, so that the optimal ratio k between the main teeth of the stator and the negative teeth of the stator 10 can be determined according to the specific drift amount, and the purpose of eliminating the drift amount of the induced potential is finally achieved.

In any of the above embodiments, preferably, the number of stator teeth is an integer multiple of 12.

In this embodiment, the number of stator teeth is limited to be an integer multiple of 12, so that the number of the excitation winding 104 is even, and the excitation winding 104, the sine winding 106 and the cosine winding 108 are regularly arranged, thereby reducing multiple harmonics except for the first fundamental wave to the maximum extent, and ensuring that the measurement error of the rotor 20 is not too large.

In any of the above embodiments, preferably, when the number of stator teeth is 24 and the number of pole pairs of the rotor 20 of the rotary transformer 1 is 2, the ratio between the stator main teeth and the stator 10 negative teeth is 0.8< k < 0.85.

As shown in fig. 7, in this embodiment, as a specific arrangement, the number of stator teeth is 24, the number of the rotor pole pairs of the rotary transformer 1 is 2, the windings are distributed along the circumferential direction in a mode of an excitation winding 1, a sine winding 2, a cosine winding 3, an excitation winding 4, a cosine winding 5, a sine winding 6, an excitation winding 7, a sine winding 8, a cosine winding 9, an excitation winding 10, a cosine winding 11, a sine winding 12, an excitation winding 13, a sine winding 14, a cosine winding 15, an excitation winding 16, a cosine winding 17, a sine winding 18, an excitation winding 19, a sine winding 20, a cosine winding 21, an excitation winding 22, a cosine winding 23, a sine winding 24, under the structural form, the ratio of the main teeth of the stator to the negative teeth of the stator 10 is 0.8< k <0.85, so that the position measurement accuracy of the rotary transformer can be further improved.

As shown in fig. 8, in any of the above embodiments, preferably, the width of the stator main teeth is 5 mm; the width of the stator secondary teeth is 6 mm.

In this embodiment, as a preferable arrangement, the width of the stator main teeth is 5 mm; the width of the stator secondary tooth is 6mm, namely k is 0.83, so that the third harmonic of the output potential can be reduced to the maximum extent, and the rotor detection precision is correspondingly improved.

In any of the above embodiments, preferably the outer profile of the rotor core is configured to produce sinusoidal track air gap permeance variation.

In any of the above embodiments, preferably, the inner side wall of the shaft hole of the rotor core is provided with a limit groove; the outer side wall of the rotating shaft is provided with a limiting rib matched with the limiting groove.

In this embodiment, a limiting groove is formed in the inner side wall of the shaft hole of the rotor core, a corresponding limiting rib matched with the limiting groove is arranged on the outer side wall of the rotating shaft, and the rotor core drives the rotating shaft to rotate under the action of the excitation magnetic field through interference fit between the rotor core and the rotating shaft, so that the measurement of parameters such as the rotating angle of the rotor is realized.

In any of the above embodiments, preferably, the stator core 102 is formed by a plurality of silicon steel sheets stacked in an axial direction of the rotating shaft; the rotor core is formed by a plurality of silicon steel sheets stacked in the axial direction of the rotating shaft, wherein the end faces of the two ends of the rotor core respectively protrude out of the end faces of the two ends of the stator core 102 in the axial direction.

In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance; the term "plurality" means two or more unless expressly limited otherwise. The terms "mounted," "connected," "fixed," and the like are to be construed broadly, and for example, "connected" may be a fixed connection, a removable connection, or an integral connection; "coupled" may be direct or indirect through an intermediary. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.