A winding method for a reluctance rotary transformer

Abstract

The present invention discloses a winding method for a reluctance rotary transformer, wherein the excitation coils are respectively wound on the 1st, 4th, 7th and 10th stator teeth, and the sine coils are respectively wound on the 2nd, 6th, 8th and 12th stator teeth, wherein the winding direction of the sine coils on the 2nd and 6th stator teeth is the same as the winding direction of the excitation coils, and the winding direction of the sine coils on the 8th and 12th stator teeth is opposite to the winding direction of the excitation coils; the cosine coils are respectively wound on the 3rd, 5th, 9th and 11th stator teeth, wherein the winding direction of the cosine coils on the 5th and 9th stator teeth is the same as the winding direction of the excitation coils, and the winding direction of the cosine coils on the 3rd and 11th stator teeth is opposite to the winding direction of the excitation coils. The present invention is used to reduce the complexity of the winding of the reluctance rotary transformer, reduce the volume of the stator, and enable the sine coil or the cosine coil to generate the desired sine and cosine waveform signals respectively.

Description

Technical Field

[0001] The invention relates to the field of rotary transformers, and in particular to a winding method for a reluctance rotary transformer. Background Art

[0002] In the servo control system, in order to obtain accurate angular position information, the rotor needs to be detected in real time. As a position sensor, the reluctance rotary transformer has the advantages of simple structure, easy processing, good reliability, and anti-interference. It is widely used in defense, automobile, industry and other fields and has a good development prospect.

[0003] At present, in order to eliminate the influence of the brush structure on the measurement accuracy, the excitation coil and sine and cosine coils of the reluctance rotary transformer are all wound on the stator. The excitation coil mainly adopts an equal-turn coil, which is wound on the stator in reverse series slot by slot, and the sine and cosine coil mainly adopts an equal-turn coil or a sine coil. Among the rotary transformers using equal-turn coils, the sine and cosine coils are wound on the stator in reverse series with teeth separated, so that each stator tooth is wound with an excitation coil and a sine and cosine coil. However, this solution also brings new technical problems: the coil winding method of the reluctance rotary transformer is relatively complicated, and the stator volume is relatively large.

[0004] Therefore, further optimizing the configuration of the coil of the reluctance rotary transformer, reducing the complexity of the winding of the coil of the reluctance rotary transformer, reducing the stator volume, and improving the output waveform have become urgent issues to be solved. Summary of the invention

[0005] In view of the above problems, the present invention is proposed to provide a winding method for a reluctance rotary transformer, to wind the reluctance rotary transformer, and to reduce the complexity of winding the reluctance rotary transformer.

[0006] The present invention provides a winding method for a reluctance rotary transformer, wherein the reluctance rotary transformer has 12 stator teeth and a pole pair number of 3, wherein the stator teeth are numbered 1, 2, ..., 12 in sequence; the reluctance rotary transformer comprises an excitation coil, a sine coil, and a cosine coil, respectively, and only one excitation coil, sine coil, or cosine coil is wound on each stator tooth. The excitation coil is wound on the 1st, 4th, 7th, and 10th stator teeth, respectively, and the excitation coil on each stator tooth has the same winding direction and number of turns.

[0007] The sinusoidal coils are respectively wound on the 2nd, 6th, 8th and 12th stator teeth, wherein the winding direction of the sinusoidal coils on the 2nd and 6th stator teeth is the same as the winding direction of the excitation coil, and the winding direction of the sinusoidal coils on the 8th and 12th stator teeth is opposite to the winding direction of the excitation coil.

[0008] The cosine coils are respectively wound on the 3rd, 5th, 9th and 11th stator teeth, wherein the winding direction of the cosine coils on the 5th and 9th stator teeth is the same as the winding direction of the excitation coil, and the winding direction of the cosine coils on the 3rd and 11th stator teeth is opposite to the winding direction of the excitation coil.

[0009] The sine coil and the cosine coil on each stator tooth have the same number of turns.

[0010] The number of turns of the sine coil and the cosine coil on each stator tooth is different from the number of turns of the excitation coil.

[0011] The widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth are the same, the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth are the same, and the widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth are greater than the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth.

[0012] The reluctance rotary transformer further includes a stator core, and the stator teeth are arranged on the stator core.

[0013] The stator teeth all extend along the radius of the stator core toward the rotor, and the stator teeth are evenly distributed along the circumferential direction of the stator core.

[0014] The beneficial technical effects of the present invention are:

[0015] (1) The present invention optimizes the winding configuration of the reluctance rotary transformer, and only one coil is wound on each stator tooth, which can be an excitation coil, a sine coil or a cosine coil, so as to reduce the complexity of the winding of the reluctance rotary transformer, reduce the stator volume, and make the sine coil or cosine coil generate corresponding sine and cosine waveform signals respectively.

[0016] (2) The present invention only increases the width of 6 stator teeth, balances the fundamental component and the constant component in the induced electromotive force, and improves the standardization of the output signal of the sine coil or cosine coil. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A winding analysis flow chart of the reluctance rotary transformer provided by the present invention;

[0019] Figure 2 This is a winding structure diagram of the reluctance rotary transformer provided by the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0021] The present invention provides a winding method for a reluctance rotary transformer, wherein only one coil is wound on each stator tooth, which may be an excitation coil, a sine coil or a cosine coil, to reduce the complexity of winding the reluctance rotary transformer, reduce the volume of the reluctance rotary transformer, and enable the sine coil or the cosine coil to generate corresponding sine and cosine waveform signals respectively. In addition, the present invention also increases the width of 6 stator teeth, balances the fundamental component and the constant component in the induced electromotive force, and improves the standardization of the output signal of the sine coil or the cosine coil.

[0022] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] In the prior art, the reluctance rotary transformer utilizes the salient pole structure of the rotor so that different rotor angles correspond to different air gap magnetic permeabilities. As the rotor rotates at a constant speed, the air gap magnetic flux is a sine and cosine function of the rotor position, so that the induced potential output by the stator two-phase signal coil changes continuously in a sine and cosine manner. Since this structural rotary transformer utilizes the reluctance effect, it is called a reluctance rotary transformer.

[0024] For the reluctance rotary transformer, when the rotor rotates, the air gap permeance under each stator tooth is an even function that changes periodically with the rotor electrical angle. The air gap permeance ρ(i) under the i-th stator tooth is expressed by Fourier series as:

[0025]

[0026] Among them, ρ 0 , μ is the constant component of magnetic permeability, the amplitude of μ subharmonic component, P is the number of pole pairs, θ is the mechanical angle of rotor position, Z s is the number of stator teeth.

[0027] Furthermore, the outer surface of the rotor is a special shape after optimization design, so that the radial air gap permeance corresponding to different angular positions of the rotor is cosine distributed, and does not contain other subharmonics except the constant component and the fundamental component. The air gap permeance ρ(i) can be simplified as:

[0028]

[0029] Among them, ρ 1 is the amplitude of the fundamental component of magnetic permeance.

[0030] Since the change of the exciting magnetic flux under each stator tooth with the rotor position is the same as the change of the magnetic permeance under the tooth, that is, the magnetic flux under the i-th stator tooth is:

[0031]

[0032] in, is the constant component amplitude of the magnetic flux, is the amplitude of the fundamental component of the magnetic flux.

[0033] In the present invention, the winding analysis flow chart of the reluctance rotary transformer is as follows: Figure 1 In order to reduce the complexity of winding the reluctance rotary transformer and reduce the volume of the reluctance rotary transformer, it is assumed that only one coil is wound on each stator tooth, which can be an excitation coil, a sine coil or a cosine coil. Therefore, the magnetic flux of the excitation coil can be obtained. Magnetic flux of a sine coil or cosine coil

[0034]

[0035]

[0036] in, is the constant component amplitude of the magnetic flux of the excitation coil, is the amplitude of the fundamental component of the magnetic flux of the excitation coil, is the constant component amplitude of the magnetic flux of the sine coil or cosine coil, It is the amplitude of the fundamental component of the magnetic flux of the sine coil or cosine coil.

[0037] According to formula (4), the total flux linkage of the excitation coil on the stator teeth can be deduced as:

[0038]

[0039] Among them, N e is the number of stator teeth wound with field coils, N ex is the number of turns of the excitation coil.

[0040] In a reluctance rotary transformer, the induced electromotive force generated by the excitation coil itself should remain constant and have nothing to do with the mechanical angle of the rotor position, that is, the flux linkage λ should be e The second term in the formula is zero, and the magnetic flux λ e It only includes the constant component, so the field coils are symmetrically arranged on the corresponding stator teeth to achieve the flux linkage λ e The second term in the formula is zero.

[0041] At this time, in order to further reduce the harmonic components in the output waveform, the sine coil and the cosine coil should be evenly distributed between two adjacent excitation coils.

[0042] For sine and cosine coils, the magnetic flux Formula (5) can be transformed into:

[0043]

[0044] In the present invention, the number of stator teeth is set to 12, the number of pole pairs P is set to 3, and the position of each stator tooth is 0, 30°, ..., 330°, and the magnetic flux of the sine coil or cosine coil on each stator tooth can be derived as follows:

[0045]

[0046] Since the output induced electromotive force of the sine coil and cosine coil of each phase in the reluctance rotary transformer should be sine and cosine respectively, the product of the magnetic flux of the sine coil and cosine coil on all stator teeth and the number of coil turns, that is, the corresponding total magnetic flux, should also be a sine and cosine signal, which can be obtained according to formula (8):

[0047]

[0048] Therefore, by winding the sine coil and cosine coil of the reluctance rotary transformer according to the above formula (9), the induced electromotive force output by the sine coil and cosine coil of each phase in the reluctance rotary transformer can be output in the form of desired sine and cosine waveforms.

[0049] In the present invention, if Figure 2 As shown, the reluctance rotary transformer is wound, wherein only one coil is wound on each stator tooth, which may be an excitation coil, a sine coil or a cosine coil, so as to reduce the complexity of the winding of the reluctance rotary transformer, reduce the volume of the reluctance rotary transformer, and enable the sine coil or the cosine coil to generate corresponding sine and cosine waveform signals respectively.

[0050] The reluctance type rotary transformer has 12 stator teeth and 3 pole pairs, wherein the stator teeth are numbered 1, 2, ..., 12. The reluctance type rotary transformer comprises an excitation coil, a sine coil, and a cosine coil, respectively, and only one excitation coil, sine coil or cosine coil is wound on each stator tooth.

[0051] like Figure 2 As shown, the excitation coils are wound on the 1st, 4th, 7th, and 10th stator teeth, respectively, and the winding direction and number of turns of the excitation coils on each stator tooth are the same. The sine coils are wound on the 2nd, 6th, 8th, and 12th stator teeth, respectively, wherein the winding direction of the sine coils on the 2nd and 6th stator teeth is the same as that of the excitation coils, and the winding direction of the sine coils on the 8th and 12th stator teeth is opposite to that of the excitation coils. The cosine coils are wound on the 3rd, 5th, 9th, and 11th stator teeth, respectively, wherein the winding direction of the cosine coils on the 5th and 9th stator teeth is the same as that of the excitation coils, and the winding direction of the cosine coils on the 3rd and 11th stator teeth is opposite to that of the excitation coils. At the same time, the number of turns of the sine coils and cosine coils on each stator tooth is the same.

[0052] Furthermore, the number of turns of the sine coil and the cosine coil on each stator tooth is different from the number of turns of the excitation coil.

[0053] In another embodiment of the present invention, the widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth in the reluctance rotary transformer are the same, the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth are the same, and the widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth are larger than the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth.

[0054] In a reluctance rotary transformer, as the width of the stator teeth increases, the peak value of the induced electromotive force in the sine and cosine coils increases significantly, causing the fundamental component in the induced electromotive force to increase, and the proportion relative to the constant component becomes larger, reducing the harmonic content and improving the standard of the output signal of the sine coil or cosine coil. Therefore, the present invention increases the width of the stator teeth and improves the standard of the output signal of the sine coil or cosine coil.

[0055] However, if the stator tooth width is too large, the slot width between adjacent stator teeth will be too small, resulting in increased leakage flux and excessive constant component. At the same time, in order to make the 12 stator teeth meet the symmetrical arrangement, the present invention only increases the width of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth to balance the fundamental component and the constant component in the induced electromotive force.

[0056] In another embodiment of the present invention, the reluctance rotary transformer further includes a stator core, the stator teeth are arranged on the stator core, each stator tooth extends along the radius of the stator core toward the rotor, and each stator tooth is evenly distributed along the circumferential direction of the stator core.

[0057] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0058] The above description shows and describes several preferred embodiments of the present invention, but as mentioned above, it should be understood that the present invention is not limited to the form disclosed herein, and should not be regarded as excluding other embodiments, but can be used in various other combinations, modifications and environments, and can be modified within the scope of the invention concept described herein through the above teachings or the technology or knowledge of the relevant field. Changes and variations made by those skilled in the art do not depart from the spirit and scope of the present invention, and should be within the scope of protection of the claims attached to the present invention.

Claims

1. A winding method for a reluctance rotary transformer, wherein the reluctance rotary transformer has 12 stator teeth and a pole pair number of 3, wherein the stator teeth are numbered 1, 2, ..., 12 in sequence; the reluctance rotary transformer comprises an excitation coil, a sine coil, and a cosine coil, respectively, and only one of the excitation coil, the sine coil, or the cosine coil is wound around each of the stator teeth; Features: The excitation coils are respectively wound on the 1st, 4th, 7th and 10th stator teeth, and the winding direction and number of turns of the excitation coils on each stator tooth are the same; The sinusoidal coils are respectively wound on the 2nd, 6th, 8th and 12th stator teeth, wherein the winding direction of the sinusoidal coils on the 2nd and 6th stator teeth is the same as the winding direction of the excitation coil, and the winding direction of the sinusoidal coils on the 8th and 12th stator teeth is opposite to the winding direction of the excitation coil; The cosine coils are respectively wound on the 3rd, 5th, 9th and 11th stator teeth, wherein the winding direction of the cosine coils on the 5th and 9th stator teeth is the same as the winding direction of the excitation coil, and the winding direction of the cosine coils on the 3rd and 11th stator teeth is opposite to the winding direction of the excitation coil; The number of turns of the sine coil and the cosine coil on each stator tooth is the same; in, is the magnetic flux of the sine coil or cosine coil on the i-th stator tooth, is the amplitude of the fundamental component of the magnetic flux of the sine coil or cosine coil, is the constant component amplitude of the magnetic flux of the sine coil or cosine coil, and θ is the mechanical angle of the rotor position.

2. The winding method of the reluctance rotary transformer according to claim 1, It is characterized in that The number of turns of the sine coil and the cosine coil on each stator tooth is different from the number of turns of the excitation coil.

3. The winding method of the reluctance rotary transformer according to claim 2, It is characterized in that The widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth are the same, the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth are the same, and the widths of the 1st, 3rd, 5th, 7th, 9th and 11th stator teeth are greater than the widths of the 2nd, 4th, 6th, 8th, 10th and 12th stator teeth.

4. The winding method of the reluctance rotary transformer according to claim 3, It is characterized in that The reluctance rotary transformer further includes a stator core, and the stator teeth are arranged on the stator core.

5. The winding method of the reluctance rotary transformer according to claim 4, It is characterized in that The stator teeth all extend along the radius of the stator core toward the rotor, and the stator teeth are evenly distributed along the circumferential direction of the stator core.

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