RESOLVER, ROTATING ELECTRIC MACHINE AND ELEVATOR HOIST

Abstract

Resolver that has: a detection stator (2); and a detection rotor (3) which is rotatable relative to the detection stator (2), wherein the detection rotor (3) comprises a plurality of individual poles (31) arranged side by side in a circumferential direction and arranged such that each of the plurality of individual poles (31) faces the detection stator (2) in a radial direction, wherein the detection stator (2) comprises a detection stator core (21) and a first detection winding group (23), a second detection winding group (24) and a plurality of excitation windings (22) provided for the detection stator core (21), wherein the detection stator core (21) comprises a plurality of teeth (27) arranged side by side in a circumferential direction, wherein the first detection winding group (23) comprises a plurality of first windings (231) as detection windings, wherein the second detection winding group (24) comprises, as detection windings, a plurality of second windings (241) which differ from the plurality of first windings (231) in a phase of a detection voltage, wherein each of the plurality of excitation windings (22) is wound around each of the plurality of teeth (27), wherein each of the plurality of first windings (231) and each of the plurality of second windings (241) are wound around different teeth (27) of the plurality of teeth (27) without being wound around the same tooth (27), wherein each of the detection windings (231, 241) and each of the plurality of excitation windings (22) wound around the same tooth (27) are arranged to be separated from each other in the radial direction, wherein the first detection winding group (23) and / or the second detection winding group (24) is an adjustment winding group, the adjustment winding group comprising the detection windings of a plurality of types which differ in a winding width in a radial direction of the detection stator (2), and wherein it is assumed that in the setting winding group, the detection windings (231) each having a maximum winding width are defined as maximum-width windings (231A) and that the detection windings (231) which are narrower in a winding width than the maximum-width windings (231A) are defined as non-maximum-width windings (231B), wherein a winding direction of conductive wires of the maximum width windings (231A) and a winding direction of the non-maximum width windings (231B) are different from each other, wherein the maximum width windings (231A) are forward-directed windings wound in a forward direction, wherein the non-maximum width windings (231B) are reverse-directed windings wound in a direction reverse to the winding direction of the forward-directed windings, wherein a range of the winding width of each of the non-maximum-wide windings (231B) falls within a range of the winding width of each of the maximum-wide windings (231A) in a radial direction of the detection stator (2) when the detection stator (2) is viewed along a circumferential direction, and wherein a center position of the non-maximum width winding (231B) coincides with a center position of the maximum width winding (231A) in the radial direction of the detection stator (2) when the detection stator (2) is viewed along the circumferential direction.

Description

Technical FieldThe present invention relates to a resolver including a detection stator and a detection rotor that rotates relative to the detection stator, a rotating electric machine including a resolver, and an elevator hoisting machine including a resolver.Technological BackgroundHeretofore, a resolver has been known in which an excitation winding and a sine-phase output winding and a cosine-phase output winding that differ by 90° in electrical angle phase of the output voltage are wound around each of teeth of a stator core, and the excitation winding, the sine-phase output winding, and the cosine-phase output winding are disposed on the same tooth so that the excitation winding is separated from the sine-phase output winding and the cosine-phase output winding in a direction in which the tooth protrudes by a partition wall of an insulating member (see, for example, Patent Literature 1).Patent Literature 2 discloses a resolver including at least one stator and a rotor, in which a plurality of teeth and slots are formed around at least one of them, and each tooth has a wound winding. From windings of n phases (n is an integer of 2 or greater), the k-th phase winding (k=1, 2,..., n) is wound around a (k+n*t)-th tooth, counted circumferentially starting from a first tooth as a reference, where the symbol * represents a multiplication and t is an integer of 0 or greater, the winding distribution of the k-th phase winding provides a sine wave winding distribution, and the phase difference between sine wave distributions provided by the winding distribution of the k-th phase winding provides an equal interval when n=3, and 90° when n=2.Patent Literature 3, which is a document under the meaning of §3(2) PatG, discloses that an excitation winding is wound around each tooth of a detecting stator core. The first output winding and the second output winding are wound around teeth different from each other, while winding of the output windings having the same phase around two adjacent teeth in the circumferential direction is avoided. When the number of pole pairs of the excitation winding is M which is an integer equal to or greater than 1 and the number of salient poles of a detection rotor is N which is an integer equal to or greater than 1, a spatial distribution of the number of turns in each of the first and second output windings is obtained by a function represented by a spatial-order sine wave |M±N|. A spatial error order δ represented by |M-|M±N|| and a spatial error order ε represented by |δ-M| are values other than 1 and 2.Citation ListPatent Literature[PTL 1] JP 2012-163 359 A[PTL 2] WO 2007 / 029 678 A1[PTL 3] DE 11 2013 007 675 T5SUMMARY OF THE INVENTIONTechnical ProblemHowever, in the prior art resolver described in Patent Literature 1, the sine-phase output winding and cosine-phase output winding are wound in such a manner that the outer edge of one overlaps with the other, which easily leads to a random development of the outer output winding and an error in the detection of the output winding angle (output winding angle). Patent Literature 1 also includes a description of another arrangement in which the sine-phase output winding and the cosine-phase output winding are separated from each other in the direction in which the tooth protrudes. In this case, the sine-phase output winding, the cosine-phase output winding, and the excitation winding are also juxtaposed in the direction in which the tooth protrudes, and if the length of the tooth is adjusted, the resultant thinness of the partition walls of the insulator tends to result in a random unwinding of the windings due to deformation of the partition walls. The width of each winding in the direction in which the tooth protrudes may be reduced to ensure that the partitions of the insulating member are sufficiently thick, but the windings still tend to be randomly developed because the thickness of each winding in the circumferential direction is thicker in this case.The present invention has been made to solve the above-described problems, and an object of the present invention is therefore to provide a resolver, a rotating electric machine, and an elevator hoisting machine that can prevent an increase in angle detection error.Solution of the ProblemAccording to an embodiment of the present invention, there are provided a resolver according to claim 1, a rotating electric machine according to claim 10, and an elevator hoisting machine according to claim 11.Advantageous Effects of the InventionAccording to the resolver, the rotating electric machine, and the elevator hoisting machine of the present invention, each first winding and each second winding are wound around different teeth without being wound around the same tooth, and the excitation winding and the detection winding wound around the same tooth are arranged so as to be separated from each other in the radial direction of the detection stator. The excitation coils, the first coils, and the second coils can thus be prevented from being wound in an undesired manner in which the outer edge of one coil type overlaps with another coil type. In addition, the need to increase the thickness of each winding type in the circumferential direction of the detection stator can be eliminated by avoiding winding all winding types, i.e., the excitation windings, the first windings, and the second windings, around the same tooth. This can reduce the chance that conductive wires of the excitation windings, the first windings, and the second windings are wound around teeth in a misaligned manner, and can prevent an angle detection error of the resolver from increasing.Brief Description of the DrawingsFIG. 1 is a front view illustrating a resolver according to a first embodiment of the present invention. FIG. 2 is an enlarged view illustrating an excitation winding and a first winding wound around one of the teeth of FIG. 1 bearing the tooth number "5". FIG. 3 is an enlarged view illustrating an excitation winding and a first winding wound around one of the teeth of FIG. 1 bearing a tooth number "7". FIG. 4 is a schematic diagram to illustrate, side by side, the excitation winding and a maximum width winding of FIG. 2 wound around the same tooth, and the excitation winding and a non-maximum width winding of FIG. 3 wound around the same tooth. FIG. 5 is a schematic diagram for illustrating a magnetic flux density distribution of a magnetic flux formed around each tooth of the teeth of FIG. 1. FIG. 6 is a graph to show a relationship between the radial positions of the maximum-width winding and the non-maximum-width winding of FIG. 4, and to show the linkage ("interconnection") of magnetic flux densities per number of turns of the maximum-width winding and the non-maximum-width winding. FIG. 7 is a schematic diagram illustrating a relationship between the radial winding width and a radial position of the maximum width winding of FIG. 4 and the radial winding width and a radial position of the non-maximum width winding of FIG. 4. FIG. 8 is a schematic diagram for illustrating a state in which the center position of the non-maximum width winding of FIG. 7 matches the center position of the maximum width winding of FIG. 7 in the radial direction of a detection stator. FIG. 9 illustrates a graph to show the ratio of the amount of misalignment between the center positions of the maximum wide winding and the non-maximum wide winding of FIG. 7 to an angle detection error of the resolver. FIG. 10 is a graph for comparing relationships between the angle detection error and the rotation angle observed when the amount of misalignment between the maximum wide winding and the non-maximum wide winding of FIG. 7 has a particular value that is not 0 and when the amount of misalignment between the maximum wide winding and the non-maximum wide winding of FIG. 7 is zero. FIG. 11 is a front view illustrating another example of the resolver according to the first embodiment of the present invention. FIG. 12 is a table for showing combinations of the number of teeth, the number of salient poles, and the order of excitation windings in an example 1-1 to an example 1-5 of the present invention. FIG. 13 is a front view illustrating a resolver according to a second embodiment of the present invention. FIG. 14 is an enlarged view illustrating an excitation winding and a maximum width winding wound around one of the teeth of FIG. 13 bearing a tooth number "5". FIG. 15 is an enlarged view illustrating an excitation winding and a non-maximum width winding wound around one of the teeth of FIG. 13 bearing a tooth number "7". FIG. 16 is a front view illustrating a resolver according to a third embodiment of the present invention. FIG. 17 is an enlarged view for illustrating an excitation winding and a maximum width winding wound around one of the teeth of FIG. 16 bearing a tooth number "1.". FIG. 18 is an enlarged view illustrating an excitation winding and a non-maximum width winding wound around one of the teeth of FIG. 16 bearing a tooth number "3". FIG. 19 is a vertical sectional view for illustrating an electric rotating machine according to a fourth embodiment of the present invention. FIG. 20 is a sectional view taken along the line XX-XX of FIG. 19. FIG. 21 is a vertical sectional view for illustrating an elevator hoisting machine according to a fifth embodiment of the present invention.DESCRIPTION OF THE EMBODIMENTSNow, exemplary embodiments of the present invention will be described with reference to the drawings.First EmbodimentFIG. 1 is a front view illustrating a resolver according to a first embodiment of the present invention. A resolver 1 includes a detection stator 2 and a detection rotor 3 constituting a magnetic body rotatable relative to the detection stator 2. The resolver 1 used in this example is an outer rotor resolver in which the detection stator 2 is disposed on the inner side of the ring-shaped detection rotor 3 in a radial direction.The detection stator 2 includes a detection stator core 21 constituting a magnetic body, a first detection winding group 23, a second detection winding group 24, and a plurality of excitation windings 22 provided on the detection stator core 21, and an insulator (not shown) constituting a non-magnetic body disposed between each of the first detection winding group 23, the second detection winding group 24, and the excitation windings 22 and the detection stator core 21. The insulation state between each of the first detection winding group 23, the second detection winding group 24, and the excitation windings 22 and the detection stator core 21 is ensured by the insulator and by an insulation coating of conductive wires included in the windings.The detection stator core 21 includes a core back 26 having a ring shape, and a plurality of teeth 27 that are arranged side by side in a circumferential direction of the detection stator core 21 and that protrude outward from the core back 26 in a radial direction of the core back 26 toward the detection rotor 3. In this example, thirty teeth 27 are equally spaced in the circumferential direction of the detection stator core 21. A slot 28 constituting a recess open toward the detection rotor 3 is formed between one tooth 27 and another tooth 27. In FIG. 1, for convenience, numerals (numerals each framed by a square frame) are continuously assigned in the circumferential direction to the respective teeth 27 as tooth numerals.Each of the excitation windings 22 is wound around one of the teeth 27. The excitation windings 22 are electrically connected in series.The first detection winding group 23 includes a plurality of first windings 231 as detection windings. The first windings 231 are electrically connected in series. This makes the first windings 231 to be detection windings all having the same phase. The second detection winding group 24 includes a plurality of second windings 241 as detection windings. The second windings 241 are electrically connected in series with each other. This makes the second windings 241 to be detection windings all having the same phase.The first windings 231 and the second windings 241 are detection windings that are different from each other in the electrical angle phase of the detection voltage. In this example, the first windings 231 serve as COS-phase detection windings and the second windings 241 serve as SIN-phase detection windings. In other words, the first windings 231 and the second windings 241 are windings configured to detect phases electrically different from each other by 90°.Each of the first windings 231 and each of the second windings 241 is wound around different teeth 27 without being wound around the same tooth 27. The first windings 231 and the second windings 241 are provided on the detection stator core 21 so as to avoid providing detection windings of the same phase in two teeth 27 adjacent to each other in the circumferential direction of the detection stator core 21. In this example, the first coils 231 are wound around teeth 27 selected from the plurality of teeth 27 all of the two teeth 27 ("other other tooth") in the circumferential direction, and the second coil 241 is wound around at least one remaining tooth among the plurality of remaining teeth 27 other than the teeth 27 wound with the first coils 231.The detection rotor 3 includes a plurality of salient poles 31 arranged side by side in a circumferential direction of the detection rotor 3. In this example, twenty salient poles 31 are equally spaced in the circumferential direction of the detection rotor 3. The detection rotor 3 is arranged to be coaxial with the detection stator 2, with the salient poles 31 facing an outer circumferential surface of the detection stator 2 in a radial direction. When the detection rotor 3 rotates relative to the detection stator 2, the pulsation of a permeability between the detection rotor 3 and the detection stator 2 changes in a sine wave pattern by the presence of the salient poles 31.Magnetomotive force is generated in each excitation winding 22 by supplying alternating current energy to the excitation winding 22. This generates a magnetic flux passing through the detection rotor 3 and the detection stator core 21. The magnetic flux concatenates the first windings 231 and the second windings 241, thereby generating voltages in the first windings 231 and the second windings 241. The permeability between the detection rotor 3 and the detection stator 2 changes in a sine wave pattern based on the rotation angle of the detection rotor 3, which means that the rotation angle of the detection rotor 3 is detected by measuring a voltage output from the first windings 231 and a voltage output from the second windings 241.Conductive wires of the excitation coils 22 are wound around all the teeth 27 with the same number of turns so that the winding directions on the teeth 27 adjacent to each other are opposite to each other. This gives the same winding width in the radial direction of the detection stator 2 (i.e., in a direction in which each tooth 27 protrudes), namely, the same radial winding width for each excitation winding 22, which also gives the same position in the radial direction of the detection stator 2, namely, the same radial position for each excitation winding 22.The first detection winding group 23 is a matching winding group including two types of first windings 231 different in winding width in the radial direction of the detection stator 2, namely, in the radial winding width. In the first detection winding group 23, a plurality of first windings 231 whose radial winding width is the largest of all the first windings 231 are referred to as maximum wide windings 231A, and a plurality of first windings 231 out of all the first windings 231 smaller than the maximum wide windings 231A in a radial winding width are referred to as non-maximum wide windings 231B. A conductive wire of each maximum width winding 231A has a number of turns larger than that of a conductive wire of each non-maximum width winding 231B. The maximum width windings 231A are forward windings wound in a forward direction, and the non-maximum width windings 231B are reverse windings wound in a direction reverse to the winding direction of the forward windings. The first windings 231 are divided into two types to adjust an offset ("offset").In the second detection winding group 24, on the other hand, each second winding 241 has the same winding width in the radial direction of the detection stator 2, namely, the same radial winding width. This makes the number of turns of a conductive wire the same at every other turn 241. The conductive wires of the second windings 241 are wound around the teeth 27 having the tooth numbers "4", "6", "10", "12", "16", "18", "22", "24", "28", and "30" in this example with the same number of turns being greater than or equal to 1. In this example, the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numerals "6", "12", "18", "24", and "30" are wound in the same winding direction as the winding direction of the conductive wires of the maximum width windings 231A, and the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numerals "4", "10", "16", "22", and "28" are wound in a winding direction reverse to the winding direction of the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numerals "6", "12", "18", "24", and "30". In other words, the second windings 241 wound around the teeth 27 having the tooth numbers "6", "12", "18", "24", and "30" are forward windings, and the second windings 241 wound around the teeth 27 having the tooth numbers "4", "10", "16", "24", and "28" are reverse windings in this example. No first windings 231 and no second windings 241 are wound around the teeth 27 having the tooth numbers "2", "8", "14", "20", and "26" to distribute the detection windings in a sine wave pattern.In the first detection winding group 23, the total number of turns of the maximum width windings 231A representing forward windings and the total number of turns of the non-maximum width windings 231B representing reverse windings are equal to each other. In the second detection winding group 24, the total number of turns of the forward windings of the second windings 241 and the total number of turns of the reverse windings of the second windings 241 are also equal to each other.The spatial distribution of the number of turns of the first windings 231 and the second windings 241 thus wound around the plurality of teeth 27 of the detection stator core 21 is given as a function expressed by a sine wave having a spatial order (order) determined in relation to a number of poles (i.e., a number of teeth) 2M (where M is an integer greater than or equal to 1) of the excitation windings 22 wound around the teeth 27 of the detection stator core 21, and the number N (where N is an integer greater than or equal to 1) of the salient poles 31 of the detection rotor 3 (i.e., a multiplication factor N of an angle). When the number of turns of the first windings 231 and the second windings 241 on the teeth 27 is given as w cos,i and w sin,i( i is 1, 2...2M), respectively, and the maximum number of turns of the first windings 231 and the second windings 241 per tooth 27 is given as w max the spatial distributions of the number of turns of the first windings 231 and the second windings 241 are expressed by formulas given below. In formula (1) to formula (6), the double character is applied in the same order as expressed. [Math. 1] [Math. 2] 2] 2] 2]Based on Formula (1) to Formula (6), the number of turns of the first windings (COS-phase detection windings) 231 and the second windings (SIN-phase detection windings) 241 are obtained by functions expressed by a sine wave of the (|M±N|)-th spatial order. From Formula (1) and Formula (4), the spatial distributions of the number of turns of the first windings 231 and the second windings 241 include functions expressed by a sine wave of the (|M-|M±N||)-th spatial order.FIG. 2 is an enlarged view for illustrating the excitation winding 22 and the first winding 231 wound around one of the teeth 27 of FIG. 1 bearing a tooth number "5". FIG. 3 is an enlarged view for illustrating the excitation winding 22 and the first winding 231 wound around one of the teeth 27 of FIG. 1 bearing a tooth number "7". The first winding 231 wound around the tooth 27 bearing the tooth number "5" is one of the maximum width windings 231A, and the first winding 231 wound around the tooth 27 bearing the tooth number "7" is one of the non-maximum width windings 231B.Each of the first windings 231 is positioned such that the distance to the core back 26 is closer to the first winding 231 than to the excitation winding 22. In other words, the maximum width winding 231A and the non-maximum width winding 231B are each positioned such that the distance) to the core back 26 from the maximum width winding 231A or the non-maximum width winding 231B is closer than from the excitation winding 22. The first winding 231 and the excitation winding 22 wound around the same tooth 27 are arranged so as to be separated from each other in the radial direction of the detection stator 2. Each second winding 241 is also positioned such that the distance to the core back 26 from the second winding 241 is closer than from the relevant excitation winding 22. The second winding 241 and the excitation winding 22 wound around the same tooth 27 are arranged so as to be separated from each other in the radial direction of the detection stator 2.In short, this means that each sense winding (i.e., each first winding 231 and each second winding 241) is positioned such that the distance to the core back 26 from the sense winding is closer than from the relevant excitation winding 22. A detection winding (i.e., a first winding 231 or a second winding 241) and an excitation winding 22 wound around the same tooth 27 are arranged so as to be separated from each other in the radial direction of the detection stator 2.Envelopes of the detection voltages of the first windings 231 and the second windings 241 with respect to an excitation voltage of the resolver having a multiplication factor N of an angle are ideally sine waves different from each other in phase by 90°. When the mechanical angle of the detection rotor 3 is given as θ [rad], and the waveforms of voltages detected in the first windings 231 and the second windings 241 are respectively given as Ec(θ) and Es(θ), the rotation angle of the detection rotor 3 obtained from the detection voltages of the first windings 231 and the second windings 241 and expressed in an electrical angle is N×tan -1( Es(θ) / Ec(θ)). An angle detection error ε(θ) [rad] (electric angle) of the resolver having a multiplication factor N of an angle is accordingly expressed by a formula (7). [Math. 3]The waveform Ec(θ) of the detection voltage of the first windings 231 and the waveform Es(θ) of the detection voltage of the second windings 241 are ideally expressed by a formula (8). Formula (8) is normalized so that the amplitude is 1. [Math 4.]When Ec(θ) and Es(θ) are the same waveforms expressed by Formula (8), the angle detection error ε(θ) is calculated as 0 by Formula (7). However, the actual waveforms Ec(θ) and Es(θ) of the detection voltages include noise caused by an amplitude difference, noise caused by a phase difference, and harmonics superimposed on the detection voltages, and thus may be different from the ideal waveforms of a sine wave as indicated by a formula (9). [Math. 5]]In formula (9), A S and A C represent the N-th order amplitudes of the detection voltages of the second windings 241 (SIN-phase detection windings) and the first detection windings 231 (COS-phase detection windings), φ S and φ C represent the N-th order phases of the detection voltages of the second windings 241 and the first windings 231, B Sk and B Ck represent the k-th (k≠N) order amplitudes of the detection voltages of the second windings 241 and the first windings 231 (where the k-th order is an order, respectively, which is different from the Nth order) and ψ Sk and T Ck represent the phases of the kth (k≠N) order of the detection voltages of the second windings 241 and the first windings 231, respectively (the kth order being an order different from the Nth order).Specifically, when offsets (namely, 0th order harmonics) are superimposed on the waveforms of the detection voltages of the first windings 231 and the second windings 241 and are indicated as Oc and Os, Ec(θ) and Es(θ) are expressed by a formula (10). [Math. 6]]The angle detection error ε(θ) when the offset components satisfy |Oc|<<1 and |Os|<<1 can be calculated by a formula (11) using the formula (7), the formula (10), and the well-known function rules. [Math. 7]The waveform Ec(θ) of voltage signals detected in the first detection winding group 23 is obtained as the sum of voltages induced in the first windings 231, and the waveform Es(θ) of voltage signals detected in the second detection winding group 24 is obtained as the sum of voltages induced in the second windings 241. The waveforms of the voltage signals are also obtained as envelopes with waveforms obtained as time derivatives of the concatenated magnetic flux. Based on Formula (7) to Formula (11), the angle detection error ε(θ) can be reduced accordingly by preventing the offsets representing harmonics superimposed on the linked magnetic flux, particularly the 0th-order harmonics, from increasing.FIG. 4 is a schematic diagram for illustrating, side by side, the excitation winding 22 and the maximum width winding 231A of FIG. 2 wound around the same tooth 27, and the excitation winding 22 and the non-maximum width winding 231B of FIG. 3 wound around the same tooth 27. In FIG. 4, the teeth 27 are arranged in parallel to each other, and the positions of end portions of the excitation windings 22 on the core back 26 side coincide in a direction orthogonal to the teeth 27 to illustrate the positional relationship between the maximum width winding 231A and the non-maximum width winding 231B in the radial direction. In FIG. 4, the end portion of each excitation winding 22 on the core back 26 side is illustrated as an origin zero to draw an x-coordinate axis having a positive direction on each tooth 27 that leads to the core back 26. The x-coordinate axis represents a coordinate axis that extends along the radial direction of the detection stator 2.The maximum width winding 231A is disposed so as to cover an area between a coordinate x 1 and a coordinate x 2. The non-maximum width winding 231B is disposed so as to cover an area between a coordinate x 3 and a coordinate x 4. In FIG. 4, x2>x4>x3>x1 is satisfied.FIG. 5 is a schematic diagram for illustrating a magnetic flux density distribution of a magnetic flux formed around each of the teeth 27 of FIG. 1. However, values of the magnetic flux density distribution illustrated in FIG. 5 are merely an example, and the magnetic flux density distribution does not always take the illustrated values. The excitation winding 22, which is supplied with an alternating current energy, forms a magnetic flux with the magnetic flux density distribution of FIG. 5 around the tooth 27. A magnetic flux formed around each tooth 27 wound with one of the excitation coils 22 has a gradient in the radial direction of the detection stator 2, and is substantially equally distributed in the circumferential direction of the detection stator 2, as illustrated in FIG. 5. In other words, the magnetic flux density around each tooth 27 has a gradient in a direction that runs along the x-coordinate axis and that is substantially the same at positions where the x-coordinates have the same value.On the tooth 27 wound with one of the first windings 231 or with one of the second windings 241, the first winding 231 or the second winding 241 and the relevant excitation winding 22 are arranged so as to be separated from each other in the radial direction of the detection stator 2. That is, the magnetic flux density of a magnetic flux that concatenates one of the first windings 231 and one of the second windings 241 with each other has a gradient in the radial direction of the detection stator 2 and is substantially equally distributed in the circumferential direction of the detection stator 2.FIG. 6 is a graph showing a relationship between the radial positions of the maximum wide winding 231A and the non-maximum wide winding 231B of FIG. 4 and the linked magnetic flux densities per number of turns of the maximum wide winding 231A and the non-maximum wide winding 231B. The magnetic flux densities shown in FIG. 6 represent the concatenated magnetic flux density of the maximum wide winding 231A along the line IVA-IVA of FIG. 4 and the concatenated magnetic flux density of the non-maximum wide winding 231B along the line IVB-IVB of FIG. 4. It is understood from FIG. 6 that the volume of a flux linkage of a detection winding changes depending on the radial position of the detection winding and the radial winding width of the detection winding. The volume of the linkage magnetic flux of the maximum width winding 231A and the volume of the linkage magnetic flux of the non-maximum width winding 231B are thus different from each other. It is also understood from FIG. 6 that also a change in the position of the non-maximum-width winding 231B relative to the position of the maximum-width winding 231A in the radial direction of the detection stator 2 changes a ratio between the linked magnetic flux volumes of the maximum-width winding 231A and the non-maximum-width winding 231B.When the conductive wires of the maximum width winding 231A and the conductive wires of the non-maximum width winding 231B are wound in mutually different directions, when the COS phase detection voltage is obtained by adding up output voltages from the first windings 231, harmonics representing noise are therefore cancelled by adjusting the positions of the non-maximum width winding 231B relative to the positions of the maximum width windings 231A in the radial direction of the detection stator 2, and as a result, an angle detection error due to the harmonic component is prevented. In addition, in particular, the offsets representing a type of harmonics superimposed on voltages induced by magnetic fluxes linking the detection windings 231 and 241 can be significantly reduced by adjusting the positions of the non-maximum-width windings 231B relative to the positions of the maximum-width windings 231A.FIG. 7 is a schematic diagram for illustrating a relationship between the radial winding width and the radial position of the maximum width winding 231A of FIG. 4 and the radial winding width and the radial position of the non-maximum width winding 231B of FIG. 4. In FIG. 7, the radial winding width of the maximum width winding 231A is indicated as h A and the radial winding width of the non-maximum width winding 231B is indicated as h B. The position of the end portion of the maximum width winding 231A on the core back 26 side is used as a reference point in the radial direction of the detection stator 2 in FIG. 7. The distance from the reference point to the center position of the non-maximum width winding 231B is illustrated as d 0, and the distance from the reference point to the end portion of the non-maximum width winding 231B on the core back 26 side is illustrated as d. FIG. 7 further includes Δd representing the distance between the center position of the maximum wide winding 231A and the center position of the non-maximum wide winding 231B in the radial direction of the detection stator 2, namely, the amount of misalignment between the maximum wide winding 231A and the non-maximum wide winding 231B. A ratio of 0<h B< h A is established in FIG. 7.The magnetic flux density of a magnetic flux formed around each tooth 27 is known to vary greatly in the radial direction of the detection stator 2 at a position close to the excitation winding 22. On the other hand, at a position away from the excitation winding 22, the magnetic flux density around the tooth 27 changes substantially in proportion to the position in the radial direction of the detection stator 2, as illustrated in FIG. 5. Therefore, when the conductive wire of the maximum width winding 231A and the conductive wire of the non-maximum width winding 231B are wound in different directions from each other, an effect is obtained in that noise is less likely to be superimposed on the maximum width winding 231A and the non-maximum width winding 231B by adjusting the position of the non-maximum width winding 231B such that both end portions of the non-maximum width winding 231B in the radial direction are included within the radial winding width h A of the maximum width winding 231A.In the first embodiment, the radial winding width h B of the non-maximum width winding 231B is included in the radial winding width h A of the maximum width winding 231A by ensuring that the radial end portions of the non-maximum width winding 231B do not fall outside the radial winding width h A of the maximum width winding 231A when the first detection winding group 23 is viewed along the circumferential direction of the detection stator 2. In other words, the ratio between the maximum width winding 231A and the non-maximum width winding 231B in the radial direction of the detection stator 2 satisfies 0<h B< h A and 0≤d≤(h A- h B).FIG. 8 is a schematic diagram for illustrating a state in which the center position of the non-maximum width winding 231B of FIG. 7 coincides with the center position of the maximum width winding 231A of FIG. 7 in the radial direction of the detection stator 2. In the first embodiment, the center position of the non-maximum width winding 231B coincides with the center position of the maximum width winding 231A in the radial direction of the detection stator 2 when the first detection winding group 23 is viewed along the circumferential direction of the detection stator 2. In other words, the misalignment amount Δd of a misalignment between the maximum wide winding 231A and the non-maximum wide winding 231B is 0 in the first embodiment.FIG. 9 illustrates a graph to show the ratio of the misalignment amount Δd of misalignment between the center positions of the maximum wide winding 231A and the non-maximum wide winding 231B of FIG. 7 to an angle detection error of the resolver 1. It is understood from FIG. 9 that an angle detection error of the resolver 1 becomes larger than the misalignment amount Δd of a misalignment between the center position of the maximum wide winding 231A and the center position of the non-maximum wide winding 231B and is at its minimum when Δd=0 is reached, that is, when d=(h A- h B) / 2 is satisfied. It is therefore understood that the angle detection error of the resolver 1 is prevented from increasing by making the center position of the maximum width winding 231A and the center position of the non-maximum width winding 231B coincide with each other in the radial direction of the detection stator 2 when the first detection winding group 23 is viewed along the circumferential direction of the detection stator 2.FIG. 10 illustrates a graph for comparing relationships between the angle detection error and the rotation angle observed when the misalignment amount Δd of misalignment between the maximum wide winding 231A and the non-maximum wide winding 231B of FIG. 7 has a particular value that is not 0 (Δd≠0), and when the misalignment amount Δd of misalignment between the maximum wide winding 231A and the non-maximum wide winding 231B of FIG. 7 is zero (Δd=0). In FIG. 10, P 1 represents the angle detection error observed when the misalignment amount Δd takes the particular value other than 0, and P 0 represents the angle detection error observed when the misalignment amount Δd is zero. It is understood from FIG. 10 that the angle detection error P 1 at a rotation angle of the detection rotor 3 is large when the misalignment amount Δd takes the particular value that is not 0, while the angle detection error P 0 decreases when the misalignment amount Δd is 0, regardless of which value the rotation angle of the detection rotor 3 takes. FIG. 10 is accordingly another evidence that the angle detection error of the resolver 1 is prevented from increasing by matching the center position of the maximum width winding 231A and the center position of the non-maximum width winding 231B in the radial direction of the detection stator 2. This ratio is established when a resolver function is satisfied regardless of which combination of the number of salient poles and the excitation order is used.As described above, the envelope waveforms of the detection voltages of the first windings 231 and the second windings 241 are desirably in sine wave patterns that are electrically different from each other by 90° in Formula (8) in order to reduce the angle detection error of the resolver 1. The COS-phase detection voltage and the SIN-phase detection voltage are induced by temporal changes of magnetic fluxes linking the detection windings. The angle detection error of the resolver 1 therefore tends to increase when the conductive wires of the detection windings are misaligned or when the positions of the two types of detection windings are far shifted from each other in the radial direction of the detection stator 2, causing an amplitude difference and a phase difference between the detection voltages of the detection windings or superposition of offsets of the detection voltages, as indicated by Formula (9).In the resolver 1 thus configured, the first windings 231 and the second windings 241 are wound around different teeth 27 without being wound around the same tooth 27, and one of the excitation windings 22 and the first winding 231 or the second winding 241 wound around the same tooth 27 are arranged such that the excitation winding 22 and the first winding 231 or the second winding 241 are separated from each other in the radial direction of the detection stator 2. Thus, overlapping between the outer periphery of the excitation winding 22, the first winding 231, or the second winding 241, and another one of the three types of windings is prevented when the windings are wound. In addition, the thicknesses of the windings 22, 231, and 241 can be prevented from increasing in the circumferential direction of the detection stator 2 by avoiding winding all three types of windings, i.e., the excitation windings 22, the first windings 231, and the second windings 241, around the same tooth 27. This can further ensure prevention of the accidental development and winding disorder of the excitation windings 22, the first windings 231, and the second windings 241, and the conductive wires of the windings 22, 231, and 241 can be prevented from being wound in a misaligned manner. The angle detection error of the resolver 1 can be accordingly prevented from increasing.The first windings 231 and the second windings 241 are arranged to be separated from the excitation windings 22 in the radial direction of the detection stator 2. Compared to the related art in which the two types of windings are wound in an overlapping manner, this arrangement is advantageous in that the positions of the first windings 231 and the positions of the second windings 241 relative to the excitation windings 22 can be adjusted independently of each other in the radial direction of the detection stator 2. The voltage amounts induced in the first windings 231 and the second windings 241 are accordingly adjustable, which helps prevent the angle detection error of the resolver 1 from increasing.The excitation coils 22 each have the same radial coil width, and the positions of the excitation coils 22 coincide with each other in the radial direction of the detection stator 2 when viewed along the circumferential direction of the detection stator 2, which can provide each tooth 27 with the same magnetic flux density distribution in the radial direction of the detection stator 2. This can reduce the offsets, the amplitude difference, and the phase difference caused in the detection voltages by misalignment of the excitation windings 22, and the angle detection error of the resolver 1 can be further prevented from increasing.The radial winding width h B of each non-maximum-width winding 231B is kept within the radial winding width h A of each maximum-width winding 231A when viewed along the circumferential direction of the detection stator 2. A range in which a magnetic flux common to the non-maximum width winding 231B and the maximum width winding 231A concatenates can be set large accordingly. This further helps prevent the angle detection error of the resolver 1, which is caused by the superposition of harmonics with the detection voltages of the two types of first windings 231 and the amplitude difference and the phase difference between the detection voltages, from increasing.The center position of the non-maximum width winding 231B and the center position of the maximum width winding 231A also coincide with each other in the radial direction of the detection stator 2 when viewed along the circumferential direction of the detection stator 2. Therefore, the angle detection error of the resolver 1 caused by the superposition of harmonics with the detection voltages of the two types of first windings 231 and by the amplitude difference and the phase difference between the detection voltages can be further prevented from increasing.In the first detection winding group 23, the total number of turns of the maximum width windings 231A representing forward windings and the total number of turns of the non-maximum width windings 231B representing reverse windings are equal to each other. A positive voltage and a negative voltage can therefore be cancelled in the first detection winding group 23, which can reduce the offsets of the detection voltages of the first detection winding group 23. This can further prevent the angle detection error of the resolver 1 from increasing. Also in the second detection winding group 24, the total number of turns of the forward windings among the second windings 241 and the total number of turns of the reverse windings among the second windings 241 are equal to each other. The offsets of detection voltages of the second detection winding group 24 can be accordingly reduced as in the first detection winding group 23, and the angle detection error of the resolver 1 can be further prevented from increasing.The radial winding width h B of each non-maximum-width winding 231B is smaller than the radial winding width h A of each maximum-width winding 231A, which makes the position of the non-maximum-width winding 231B in the radial direction of the detection stator 2 adjustable in a larger range than a position adjustable range for the maximum-width winding 231A. The angle detection error of the resolver 1 can be accordingly prevented from increasing by adjusting the position of each non-maximum wide winding 231B in the radial direction even when there is little space for position adjustment for the maximum wide winding 231A in the radial direction. This can improve the degree of freedom in designing the resolver 1.In the detection stator 2, on the other hand, the number of non-maximum width windings 231B is larger than the number of maximum width windings 231A. The number of windings set in one position can be accordingly reduced by setting the positions of the maximum wide windings 231A that are less than the non-maximum wide windings 231B in the radial direction when there is sufficient space for position adjustment for the maximum wide windings 231A in the radial direction. This can facilitate the burden of position adjustment work in which the positions of the detection windings 231 and 241 are adjusted.The first windings 231 and the second windings 241 are each positioned such that the distance to the core back 26 is closer to the first winding 231 or the second winding 241 than to the relevant excitation winding 22 in the example described above. Alternatively, the first windings 231, the second windings 241, and the excitation windings 22 could be positioned as illustrated in FIG. 11 in which the distance to the core back 26 is closer to the excitation winding 22 than to the first winding 231 or to the second winding 241. In other words, the first windings 231 and the second windings 241 could be positioned such that the distance to the detection rotor 3 is closer to the first windings 231 and the second windings 241 than to the excitation windings 22. The excitation windings 22 in this case each have the same radial winding width and also correspond to one another in the radial direction. In this way, the angle detection error of the resolver 1 can also be suppressed while preventing an increase in the size of the resolver 1.The number of teeth 27 of the detection stator 2 is thirty in the above-described example, and the number of salient poles 31 of the detection rotor 3 is twenty. However, the combination of the number of teeth 27 and the number of salient poles 31 is not limited thereto as long as the combination makes the resolver perform its function. Therefore, the present invention is also applicable to Example 1-1 to Example 1-5 of FIG. 12, in which the combination of the number of teeth 27 and the number of salient poles 31 (i.e., an angle multiplication factor) is different from the combination of the thirty teeth 27 and the twenty salient poles 31 of the above-described example, and the angle detection error of the resolver can also be prevented from increasing in the examples.FIG. 12 is a table for showing combinations of the number of teeth 27, the number of salient poles 31 (i.e., angle multiplying factor), and the order of the excitation windings 22 in Example 1-1 to Example 1-5 of the present invention. As shown in FIG. 12, the number of winding distributions of the first windings 231 and the second windings 241 are given a discrete sine pattern by applying the angle multiplication factor N and the order M of the excitation windings 22 to Formula (1) to Formula (6), and the order of the angle detection error of the resolver is determined by Formula (7) to Formula (11) in each of Examples 1-1 to Example 1-5.Example 1-1, namely, the same argument as that illustrated in FIGS. 1 to 10, is established when the number of turns of the windings constituting the first detection winding group or the second detection winding group has a number of turn distribution in a sine wave pattern, the number of turns or the winding widths of the constituent windings have a size ratio, and the positions of the windings constituting the detection winding group are adjustable. The spatial distributions of the number of turns of the first detection winding group and the second detection winding group are expressed by a sine wave of the (|M±N|)-th or (|M-|M±N|)-th spatial order. A fifth spatial order number of a winding distribution ("fifth spatial order number of turns distribution") can therefore be given in Example 1-1 (the fifth order is equivalent to the 35th order (|2M-|M±N|=|30-35|=5), which is obtained by shifting the COS value by a phase of 2π in Formula (1) to Formula (6))). The fifth-order spatial distribution means, in the case of a resolver having thirty teeth, that the same winding pattern appears every sixth tooth and that three teeth and remaining three teeth in a single winding pattern are assigned to windings of the first detection winding group and windings of the second detection winding group, respectively, having phases that are electrically different from each other by 90°. The first detection winding group may accordingly include both the maximum-width windings 231A and the non-maximum-width windings 231B when the number of turns has a fifth-order spatial distribution, and the above argument is established.In each of the examples shown in FIG. 12, the number of winding distribution may be a fifth-order spatial distribution or a third-order spatial distribution, and windings of the first detection winding group and the second detection winding group may be configured to have a magnitude ratio. A winding position adjustment for reducing the angle detection error can therefore be performed based on the above-described argument in the examples.As described above, the alignment of the conductive wires of the windings 22, 231, and 241 can be improved by arranging the excitation winding 22 and the first winding 231 or the second winding 241 wound around the same tooth 27 so that the windings 22 and 231, or 22 and 241 are separated from each other, and the angle detection error of the resolver can also be reduced by adjusting the positions of the first windings 231 and the second windings 241. It is to be understood that the present invention is also applicable to combinations of the number of teeth 27 and the number of salient poles 31 not shown in FIG. 12 when the number of salient poles and the excitation order are combined so that the number of turns has such a spatial distribution as described above.Second EmbodimentFIG. 13 is a front view illustrating a resolver according to a second embodiment of the present invention. The resolver 1 in the second embodiment has the same configuration as that in the first embodiment except for the configuration of an insulator 30. the insulator 30, which is a non-magnetic body, is disposed between the detection stator core 21 and the excitation windings 22, between the detection stator core 21 and the first detection winding group 23, and between the detection stator core 21 and the second detection winding group 24. The insulator 30 includes a plurality of partition portions 301 each of which is disposed between the excitation winding 22 and the detection winding 231 or 241 wound around the same tooth 27, and a plurality of protruding portions 302 each of which is disposed between one of the detection windings 231 or one of the detection windings 241 and the core back 26. The excitation coils 22 and the detection coils 231 and 241 are arranged so as to be separated from each other via the separation portions 301 in the radial direction of the detection stator 2. The detection coils 231 and 241 and the core back 26 are arranged so as to be separated from each other in the radial direction of the detection stator 2 via the protruding portions 302.FIG. 14 is an enlarged view for illustrating the excitation winding 22 and the maximum width winding 231A wound around one of the teeth 27 of FIG. 13 bearing a tooth number "5". FIG. 15 is an enlarged view for illustrating the excitation winding 22 and the non-maximum width winding 231B wound around one of the teeth 27 of FIG. 13 bearing a tooth number "7". The maximum width winding 231A is positioned relative to the excitation winding 22 in the radial direction of the detection stator 2 by adjusting the thickness of a separation portion 301A and the thickness of a protruding portion 302A, as illustrated in FIG. 14. The non-maximum width winding 231B is positioned relative to the excitation winding 22 in the radial direction of the detection stator 2 by adjusting the thickness of a separation portion 301B and the thickness of a protruding portion 302B, as illustrated in FIG. 15.In this example, where the radial winding width of the maximum width winding 231A is wider than the radial winding width of the non-maximum width winding 231B, the partitioning portion 301B is thicker than the partitioning portion 301A, and the protruding portion 302B is thicker than the protruding portion 302A. The rest of the configuration is the same as in the first embodiment.In the resolver 1 thus configured, the insulator 30 constituting a non-magnetic body includes the separation portions 301, each of which is disposed between the excitation winding 22 and the detection winding 231 or 241, wound around the same tooth 27, thereby ensuring that the state of electrical insulation between the excitation winding 22 and the detection winding 231 or 241 is maintained the more, and thereby keeping the conductive wires of the excitation windings 22 and the detection windings 231 and 241 more aligned. In addition, the detection windings 231 and 241 can be more accurately positioned relative to the excitation windings 22 in the radial direction of the detection stator 2 by adjusting the thicknesses of the separation portions 301. Harmonics of magnetic fluxes can be reduced in this manner, which further contributes to preventing the angle detection error of the resolver 1 from increasing.The insulator 30 further includes the protruding portions 302 each of which is disposed between one of the first windings 231 and the core back 26 or between one of the second windings 241 and the core back 26. Therefore, the first winding 231 and the second winding 241 can be positioned more accurately relative to the excitation winding 22 in the radial direction of the detection stator 2, which further contributes to preventing the angle detection error of the resolver 1 from increasing.Third EmbodimentFIG. 16 is a front view illustrating the resolver 1 according to a third embodiment of the present invention. The resolver 1 used in this embodiment is an inner rotor resolver in which the detection rotor 3 constituting a magnetic body is disposed on the inner side in a radial direction of the ring-shaped detection stator 2.The detection stator 2 includes the detection stator core 21 constituting a magnetic body, the plurality of excitation coils 22, the first detection coil group 23 and the second detection coil group 24 provided on the detection stator core 21, and an insulator 30 constituting a non-magnetic body and disposed between each of the excitation coils 22, the first detection coil group 23 and the second detection coil group 24 and the detection stator core 21. The state of insulation between each of the excitation coils 22, the first detection coil group 23, and the second detection coil group 24, and the detection stator core 21 is ensured by the insulator.The detection stator core 21 includes the core back 26 having a ring shape and the plurality of teeth 27 that are arranged side by side in the circumferential direction of the detection stator core 21 and that protrude from the core back 26 inward in a radial direction of the core back 26 toward the detection rotor 3. In this example, eighteen teeth 27 are equally spaced in the circumferential direction of the detection stator core 21. The slot 28, which is a recess open toward the detection rotor 3, is formed between one tooth 27 and another tooth 27. In FIG. 16, numerals (numerals each framed by a square frame) are continuously assigned in the circumferential direction to the respective teeth 27 as tooth numerals for convenience.Each of the plurality of excitation windings 22 is wound around one of the plurality of teeth 27. The excitation windings 22 are electrically connected in series.The first detection winding group 23 includes a plurality of first windings 231 as detection windings. The first coils 231 are electrically connected in series to each other. This makes the first windings 231 become detection windings all having the same phase. The second detection winding group 24 includes a plurality of second windings 241 as detection windings. The second coils 241 are electrically connected in series to each other. This makes the second windings 241 become detection windings all having the same phase.The first windings 231 and the second windings 241 constitute detection windings that are different from each other in the electrical angle phase of the detection voltage. In this example, the first windings 231 serve as COS-phase detection windings and the second windings 241 serve as DIN-phase detection windings. In other words, the first windings 231 and the second windings 241 are windings configured to detect phases electrically different from each other by 90°.Each of the plurality of first windings 231 and each of the plurality of second windings 241 is wound around different teeth 27 without being wound around the same tooth 27. The first windings 231 and the second windings 241 are provided on the detection stator core 21 so as to prevent detection windings of the same phase from being provided in two teeth 27 adjacent to each other in the circumferential direction of the detection stator core 21. In this example, the first coils 231 are wound around teeth 27 that are each second ("other other-ether") tooth 27 selected from the plurality of teeth 27 in the circumferential direction, and the second coil 241 is wound around at least one of the plurality of remaining teeth 27 that are not the teeth 27 wound around the first coils 231.The detection rotor 3 includes a plurality of salient poles 31 arranged side by side in the circumferential direction of the detection rotor 3. In this example, fifteen salient poles 31 are equally spaced in the circumferential direction of the detection rotor 3. The detection rotor 3 is arranged to be coaxially aligned with the detection stator 2 with the salient poles 31 facing the inner circumferential surface of the detection stator 2 in a radial direction. When the detection rotor 3 rotates relative to the detection stator 2, the pulsation of the permeability between the detection rotor 3 and the detection stator 2 changes in a sine wave pattern by the presence of the salient poles 31.A magnetomotive force is generated in each excitation winding 22 by supplying an AC power to the excitation winding 22. This generates a magnetic flux passing through the detection rotor 3 and the detection stator core 21. The magnetic flux concatenates the first windings 231 and the second windings 241, thereby generating voltages in the first windings 231 and the second windings 241. The permeability between the detection rotor 3 and the detection stator 2 changes in a sine wave pattern based on the rotation angle of the detection rotor 3, which means that the rotation angle of the detection rotor 3 is detected by measuring a voltage output from the first windings 231 and a voltage output from the second windings 241.Conductive wires of the excitation coils 22 are wound around all the teeth 27 with the same number of turns so that the winding directions on the teeth 27 adjacent to each other are opposite to each other. This gives each excitation winding 22 the same radial winding width. This also gives each excitation winding 22 the same radial position.The first detection winding group 23 is a matching winding group including two types of first windings 231 different from each other in radial winding width. In the first detection winding group 23, a plurality of first windings 231 of which the radial winding width is the largest of all the first windings 231 are referred to as maximum wide windings 231A, and a plurality of first windings 231 of all the first windings 231 of which the maximum wide windings 231A in the radial winding width are referred to as non-maximum wide windings 231B. A conductive wire of each maximum width winding 231A has a number of turns larger than that of a conductive wire of a non-maximum width winding 231B. The maximum width windings 231A are forward windings wound in a forward direction, and the non-maximum width windings 231B are reverse windings wound in a reverse direction to the winding direction of the forward windings.In the second detection winding group 24, on the other hand, each second winding 241 has the same radial winding width. This makes the number of turns of a conductive wire the same at every other winding width 241. The conductive wires of the second windings 241 are wound around the teeth 27 having the tooth numbers "2", "6", "8", "12", "14", and "18" in this example, with the same number of turns being equal to or greater than 1. In this example, the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numbers "2", "8", and "14" are wound in the same winding direction as the winding direction of the conductive wires of the maximum width windings 231A, and the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numbers "6", "12", and "18" are wound in a winding direction reverse to the winding direction of the conductive wires of the second windings 241 wound around the teeth 27 having the tooth numbers "2", "8", and "14". In other words, the second windings 241 wound around the teeth 27 having the tooth numbers "2", "8", and "14" are forward windings, and the second windings 241 wound around the teeth 27 having the tooth numbers "6", "12", and "18" are reverse windings in this example. No first windings 231 and no second windings 241 are wound around the teeth 27 having the tooth numbers "4", "10", and "16" to distribute the detection windings in a sine wave pattern.In the first detection winding group 23, the total number of turns of the maximum width windings 231A that are forward windings and the total number of turns of the non-maximum width windings 231B that are reverse windings are equal to each other. In the second detection winding group 24, the total number of turns of the forward windings of the second windings 241 and the total number of turns of the reverse windings of the second windings 241 are also equal to each other.The spatial distribution of the number of turns of the first windings 231 and the second windings 241 thus wound around the plurality of teeth 27 of the detection stator core 21 is given as a function expressed by a sine wave having a spatial order determined in relation to the number of poles (i.e., number of teeth) 2M (M is an integer greater than or equal to 1) of the excitation windings 22 wound around the teeth 27 of the detection stator core 21, and the number N (N is an integer greater than or equal to 1) of the salient poles 31 of the detection rotor 3 (i.e., the angle multiplication factor N).Each sense winding (i.e., each first winding 231 and each second winding 241) is positioned such that the distance to the core back 26 is closer to the sense winding than to the relevant excitation winding 22. A detection winding (i.e., a first winding 231 or a second winding 241) and excitation winding 22 wound around the same tooth 27 are arranged so as to be separated from each other in the radial direction of the detection stator 2.The insulator 30 includes the plurality of separation portions 301, each of which is disposed between the excitation winding 22 and the detection winding 231 or 241 wound around the same tooth 27, and the plurality of protruding portions 302, each of which is disposed between one of the detection windings 231 or one of the detection windings 241 and the core back 26. The excitation coils 22 and detection coils 231 and 241 are arranged so as to be separated from each other via the separation portions 301 in the radial direction of the detection stator 2. The detection coils 231 and 241 and the core back 26 are arranged so as to be separated from each other in the radial direction of the detection stator 2 via the protruding portions 302.FIG. 17 is an enlarged view for illustrating the excitation winding 22 and the maximum width winding 231A wound around one of the teeth 27 of FIG. 16 bearing a tooth number "1.". FIG. 18 is an enlarged view for illustrating the excitation winding 22 and the non-maximum width winding 231B wound around one of the teeth 27 of FIG. 16 bearing a tooth number "3". The maximum width winding 231A is positioned relative to the excitation winding 22 in the radial direction of the detection stator 2 by adjusting the thickness of the separation portion 301A and the thickness of the protruding portion 302A, as illustrated in FIG. 17. The non-maximum width winding 231B is positioned relative to the excitation winding 22 in the radial direction of the detection stator 2 by adjusting the thickness of the separation portion 301B and the thickness of the protruding portion 302B, as illustrated in FIG. 18. The positional relationship between the maximum width winding 231A and the non-maximum width winding 231B when the first detection winding group 23 is viewed along the circumferential direction of the detection stator 2 is the same as in the first embodiment.In this example, where the radial winding width of the maximum width winding 231A is wider than the radial winding width of the non-maximum width winding 231B, the partitioning portion 301B is thicker than the partitioning portion 301A and the protruding portion 302B is thicker than the protruding portion 302A. The rest of the configuration is the same as in the first embodiment.In this way, when applied to an inner rotor resolver 1 in which the detection rotor 3 is disposed on the inner side in the radial direction of the detection stator 2 and is rotatable relative to the detection stator 2, the present invention is capable of more ensuring prevention of the random unwinding and winding disorder of the excitation windings 22, the first windings 231, and the second windings 241, and can prevent the angle detection error of the resolver 1 from increasing as in the first embodiment and the second embodiment.The number of teeth 27 of the detection stator 2 is eighteen, and the number of salient poles 31 of the detection rotor 3 is fifteen in the example described above. However, the combination of the number of teeth 27 and the number of salient poles 31 is not limited thereto as long as the combination makes the resolver perform its function as is the case for the combinations described in the first embodiment with reference to FIG. 12.Fourth EmbodimentFIG. 19 is a vertical sectional view for illustrating an electric rotating machine according to a fourth embodiment of the present invention. FIG. 20 is a sectional view taken along the line XX-XX of FIG. 19. A rotating electric machine 101 in FIG. 19 includes a stator 102 that is annular, a rotor 103 that is disposed on the inside of the stator 102 and that rotates relative to the stator 102, and a housing 140 that supports the stator 102 and the rotor 103.The housing 104 includes a housing main body 105 shaped like a board and a housing tube portion 106 which is cylindrical and which is fixed to an outer peripheral portion of the housing main body 105. A through hole 107 is formed in a central portion of the housing main body 105. As illustrated in FIG. 19, a support shaft 108 is fixed to the housing 104. The support shaft 108 is fixed to the housing main body 105 and is disposed along a central axis line of the housing tube portion 106. The rotor 103 is attached to the support shaft 108 via bearings 109 in a rotatable manner. The rotor 103 is supported by the housing 104 via the support shaft 108.The stator 102 is arranged to be coaxial with the rotor 103. The stator 102 includes a stator core 110 that is annular and that surrounds the outer periphery of the rotor 103, a plurality of stator windings 111 that are provided in the stator core 110 and that are aligned side by side in a circumferential direction of the stator core 110, and an insulator 112 that is provided in the stator core 110 and that is to be interposed between the stator core 110 and the stator windings 111. The stator 102 is supported by the housing 104, with the stator core 110 fitting into the housing tube portion 106. The state of insulation between the stator windings 111 and the stator core 110 is ensured by the insulator 112.The stator core 110 is constructed of a plurality of steel sheets that are layered in an axis line direction of the support shaft 108 and that constitute magnetic bodies. The stator core 110 includes a rear yoke portion 113 having a ring shape along an inner circumferential surface of the housing tube portion 106, and a plurality of magnetic pole tooth portions 114 that project inward from the rear yoke portion 113 in a radial direction and that are arranged apart from each other in the circumferential direction of the stator core 110. The magnetic pole tooth portions 114 are equally spaced in the circumferential direction of the stator core 110.The stator windings 111 are separately provided in the magnetic pole tooth portions 114, which means that the stator windings 111 are equally spaced in the circumferential direction of the stator core 110. A rotating magnetic field is generated in the stator 102 by establishing an electrical connection with the stator windings 111. The rotor 103 rotates about the axis line of the support shaft 108 by the generation of the rotating magnetic field in the stator 102.The rotor 103 includes a rotor yoke 115 and a plurality of permanent magnets (rotor magnetic pole portions) 116 provided in the rotor yoke 115.The rotor yoke 115 is a mold ("mold") made of cast iron. The rotor yoke 115 includes, as illustrated in FIG. 19, a rotor yoke main body 117 to which the bearings 109 are attached, and a rotor tube portion 118 that is fixed to an outer peripheral portion of the rotor yoke main body 117 and that is disposed to be coaxial with the support shaft 108.The rotor yoke 115 is disposed on the inner side of the stator 102, with an outer circumferential surface of the rotor tube portion 118 facing the stator 102 in a radial direction of the rotor 103. This makes the outer circumferential surface of the rotor tube portion 118 face front end surfaces of the magnetic pole tooth portions 114 in the radial direction.The permanent magnets 116 are provided on the outer circumferential surface of the rotor tube portion 118. The permanent magnets 116 are spaced apart from each other in a circumferential direction (namely, the rotational direction of the rotor 103) of the rotor 103 in a space between the rotor tube portion 118 and the stator 102. The permanent magnets 116 are equally spaced in the circumferential direction of the rotor 103 in this example.A through hole 121 is formed in a central portion of the rotor yoke main body 117. A resolver shaft 122 that reaches the inside of the through hole 121 is provided in a front end portion of the support shaft 108 so as to be coaxial with the support shaft 108. The resolver shaft 122 is smaller in outer diameter than the support shaft 108.An outer rotor resolver 1 configured to detect the rotation angle of the rotor 103 is provided in the through hole 121 of the rotor yoke main body 117. The resolver 1 includes a detection stator 2 fixed to the resolver shaft 122, and a detection rotor 3 that faces the detection stator 2 in a radial direction and that constitutes a magnetic body that is rotatable relative to the detection stator 2. The detection rotor 3 is fixed to an inner surface of the through hole 121 of the rotor yoke main body 117. This allows the detection rotor 3 to rotate integrally with the rotor yoke main body 117 and coaxially with the support shaft 108 and the resolver shaft 122. The detection stator 2 and the detection rotor 3 have the same configurations as in the first embodiment.By applying the present invention in this manner to the resolver 1 provided in the rotating electrical machine 101, the prevention of an increase in detection error can be more ensured when the rotation angle of the rotor 103 of the rotating electrical machine 101 is detected. The control precision for the position and number of revolutions of the rotor 103 in the rotating electric machine 101 can thus be improved.The resolver 1 of the first embodiment is provided in the rotating electric machine 101 in the example described above. The rotating electric machine 101 may instead be provided with the resolver 1 of the second embodiment.In the example described above, the resolver 1 could be applied to the rotating electric machine 101 functioning as a motor or to a rotating electric machine 101 functioning as a generator.Fifth EmbodimentThe inner rotor resolver 1 according to the third embodiment could be applied to an elevator hoisting machine. FIG. 21 is a vertical sectional view for illustrating an elevator hoisting machine according to a fifth embodiment of the present invention. An elevator hoisting machine 130 in FIG. 21 includes the inner rotor resolver 1 according to the third embodiment, a motor 131, and a drive pulley 132 that rotates by a driving force of the motor 131.The motor 131 is a rotating electric machine configured to include a stator 102 having a ring shape, a rotor 103 provided on the inside of the stator 102 and rotatable relative to the stator 102, and a housing 104 supporting the stator 102 and the rotor 103.A support shaft 108 of the housing 104 is a hollow, i.e., tubular, axis, the interior of which is connected to a through hole 107 of a housing main body 105. A rotor yoke 115 of the rotor 103 includes, in addition to a rotor yoke main body 117 and a rotor tube portion 118, a resolver shaft 119 that is fixed to a central portion of the rotor yoke main body 117 and that reaches the inside of the through hole 107 via the inside of the support shaft 108. The rest of the configuration of the motor 131 is the same as the configuration of the rotating electrical machine 101 according to the fourth embodiment.The inner rotor resolver 1 configured to detect the rotation angle of the rotor 103 is provided in the through hole 107 of the housing main body 105. The resolver 1 includes a detection stator 2 fixed to the case main body 105 inside the through hole 107, and a detection rotor 3 facing the detection stator 2 in a radial direction and constituting a magnetic body rotatable relative to the detection stator 2. The detection rotor 3 is fixed to the resolver shaft 119. This allows the detection rotor 3 to rotate integrally with the rotor 103 about an axis line of the resolver shaft 119 when establishing electrical connection with the stator windings 111.The drive roller 132 is integrally molded with the rotor yoke 115. The drive roller 132 is thus supported by the support shaft 108 via bearings 109 in a manner that allows the drive roller 132 to freely rotate. The material of the drive roller 132 and the rotor yoke 115 is cast iron in this example. The drive roller 132 is provided outside the range of the stator 102 in the direction of an axis line of the support shaft 108. The drive roller 132 rotates about the axis line of the support shaft 108 with the rotation of the rotor 103. A plurality of main rope use grooves 133 are formed in an outer circumferential surface of the drive pulley 132 along a circumferential direction of the drive pulley 132.A plurality of main ropes from which an elevator car (not shown) and a counterweight (not shown) are suspended are wound around the drive pulley 132 along the main rope use grooves 133. The elevator car and the counterweight are raised and lowered in a hoistway by the rotation of the drive pulley 132.A brake device 134 configured to apply a braking force to the drive roller 132 and the rotor 103 is provided inside the rotor tube portion 118. The brake device 134 includes a brake shoe (not shown) displaceable in a radial direction of the rotor 103 relative to the rotor tube portion 118. The brake device 134 applies a braking force to the drive roller 132 and the rotor 103 by bringing the brake shoe into contact with an inner circumferential surface of the rotor tube portion 118, and cancels the braking force to the drive roller 132 and the rotor 103 by pulling the brake shoe away from the rotor tube portion 118.In the thus configured elevator hoisting machine, the inner rotor resolver 1 according to the third embodiment is provided in the motor 131, and the same effects as those in the third embodiment can be obtained accordingly. In other words, the position and the number of revolutions of the rotor 103 in the rotating electrical machine 101 can be controlled with improved precision.In the above-described example, the resolver 1 is provided in the elevator hoisting machine 130 in which the drive pulley 132 is unitary with the rotor 103. The resolver 1 could instead be provided in a transmission hoisting machine (hoisting hoisting machine) in which a gear device including a plurality of intermeshing gears is installed in a motor serving as a rotating electric machine, so that rotation of a rotor included in the motor is transmitted to the drive pulley 132 through the gear device. The drive roller 132 rotates in this case with the rotation of the rotor included in the motor at a rotation number that is decreased from a rotation number of the rotor by a certain gear ratio.In the example described above, the rotating electric machine 101 according to the fourth embodiment could be applied as the motor 131 to the elevator hoisting machine. When the rotating electric machine 101 according to the fourth embodiment is applied as the motor 131 to the elevator hoisting machine, the outer rotor resolver 1 according to the first embodiment or the second embodiment is provided in the motor 131.In the fourth embodiment, the inner rotor resolver 1 according to the third embodiment may be provided in a rotating electric machine having the same configuration as the configuration of the motor 131 in the fifth embodiment.In the fourth embodiment and the fifth embodiment, the present invention is applied to an inner rotor rotary electric machine in which the annular stator 102 surrounds the outer periphery of the rotor 103. The present invention could instead be applied to an outer rotor rotating electric machine in which the ring-shaped rotor 103 surrounds the outer periphery of the stator 102.In the fourth embodiment and the fifth embodiment, the resolver 1 is provided in a permanent magnet motor in which the permanent magnets 116 are included in the rotor 103. The present invention is not limited thereto, and the resolver 1 may be provided in an induction motor, for example.In the above-described respective embodiments, the first windings 231 serve as COS-phase detection windings and the second windings 241 serve as SIN-phase detection windings. However, the first windings 231 could be used as the SIN-phase detection windings, and the second windings 241 could be used as the COS-phase detection windings.In the above-described respective embodiments, two types of first windings 231 different in radial winding width from each other are included in the first detection winding group 23. However, the first detection winding group 23 may include three or more types of first windings 231 different from each other in a radial winding width. In this case, a plurality of first windings 231 of one type each having a maximum radial winding width are defined as maximum wide windings, and a plurality of first windings 231 of other types smaller in winding width than the maximum wide windings in radial winding width are defined as non-maximum wide windings. Further, in this case, by adjusting the respective radial positions of the first windings 231 of each type, the total radial winding width of each non-maximum width winding falls within the radial winding width of the maximum width windings when the first detection winding group 23 is viewed along the circumferential direction of the detection stator 2.In the above-described respective embodiments, the first detection winding group 23 is used as a matching winding group including a plurality of types of detection windings each having a different radial winding width. However, the second detection winding group 24 could be used as the adjustment detection winding group. In this case, the types of the radial winding widths of the respective second windings 241 included in the second detection winding group 24 may be two types or three or more types.In the above-described respective embodiments, as the first detection winding group 23, the adjustment winding group including a plurality of types of the first detection windings 231 different from each other in a radial winding width is used. However, the respective first windings 231 included in the first detection winding group 23 may have the same radial winding width. Even when applying this configuration, a case in which the excitation winding 22, the first winding 231, and the second winding 241 are all wound around the same tooth 27 could be avoided, and winding collapse and winding fluctuations of the windings 22, 231, and 241 on the teeth 27 can be suppressed accordingly. In other words, the present invention may be applicable to a case where the number of turns changes, and may be applied to a case where the same winding width is also used when two or more winding widths are used.In the above-described example, the present invention is applied to a resolver of variable resistance ("resolution"). The present invention could be applied to a rotary transformer resolver.

Claims

A resolver comprising: a detection stator (2); and a detection rotor (3) rotatable relative to the detection stator (2), the detection rotor (3) comprising a plurality of salient poles (31) arranged side by side in a circumferential direction and arranged such that each of the plurality of salient poles (31) faces the detection stator (2) in a radial direction, wherein the detection stator (2) comprises a detection stator core (21), and a first detection winding group (23), a second detection winding group (24), and a plurality of excitation windings (22) provided for the detection stator core (21), wherein the detection stator core (21) comprises a plurality of teeth (27) arranged side by side in a circumferential direction, wherein the first detection winding group (23) comprises a plurality of first windings (231) as detection windings, the second detection winding group (24) comprises, as detection windings, a plurality of second windings (241) different from the plurality of first windings (231) in a phase of a detection voltage, each of the plurality of excitation windings (22) is wound around each of the plurality of teeth (27), each of the plurality of first windings (231) and each of the plurality of second windings (241) are wound around mutually different teeth (27) of the plurality of teeth (27) without being wound around the same tooth (27), each of the detection windings (231, 241) and each of the plurality of excitation windings (22) wound around the same tooth (27) being so arranged, that they are separated from each other in the radial direction, wherein the first detection winding group (23) and / or the second detection winding group (24) is a setting winding group, wherein the setting winding group comprises the detection windings of a plurality of types different in winding width in a radial direction of the detection stator (2), and wherein it is assumed that in the setting winding group, the detection windings (231) each having a maximum winding width are defined as maximum wide windings (231A), and that the detection windings (231) narrower in winding width than the maximum wide windings (231A) are defined as non-maximum wide windings (231B), wherein a winding direction of conductive wires of the maximum wide windings (231A) and a winding direction of the non-maximum wide windings (231B) are different from each other, wherein the maximum width windings (231A) are forward windings wound in a forward direction, the non-maximum width windings (231B) are reverse windings wound in a direction reverse to the winding direction of the forward windings, a range of the winding width of each of the non-maximum width windings (231B) falls within a range of the winding width of each of the maximum width windings (231A) in a radial direction of the detection stator (2) when the detection stator (2) is viewed along a circumferential direction, and a center position of the non-maximum width winding (231B) coincides with a center position of the maximum width winding (231A) in the radial direction of the detection stator (2) when the detection stator (2) is viewed along the circumferential direction.The resolver according to claim 1, wherein the number of the non-maximum width windings (231B) is larger than the number of the maximum width windings (231A).The resolver according to claim 1 or 2, wherein positions of the plurality of excitation windings (22) coincide with each other in the radial direction of the detection stator (2) when viewed along the circumferential direction of the detection stator (2).The resolver according to any one of claims 1 to 3, wherein each of the plurality of excitation windings (22) is wound around one of the plurality of teeth (27) such that conductive wires of the excitation windings (22) are wound on adjacent teeth (27) in directions opposite to each other, wherein all of the plurality of first windings (231) are wound around teeth (27) selected from the plurality of teeth (27) in the circumferential direction, and wherein the plurality of second windings (241) are wound around at least one of the plurality of teeth (27) not wound with any of the plurality of first windings (231).The resolver according to any one of claims 1 to 4, wherein a number of pole pairs of the plurality of excitation windings (22) is M, which is an integer greater than or equal to 1, wherein a number of salient poles (31) is N, which is an integer greater than or equal to 1, wherein spatial distributions of a number of turns of the plurality of first windings and the plurality of second windings are respectively obtained from a sum of functions expressed by a sine wave of a (|M|N|)-th spatial order and functions expressed by a sine wave of a (|M-|M±N|)-th spatial order, wherein the sine wave of the (|M-|M+N|)-th spatial order has an amplitude, which is equal to an amplitude of the sine wave of the (|M|N|)-th spatial order, wherein the number of pole pairs M of the plurality of excitation windings (22) is 9, and wherein the number of single poles (31) is N 15, 24, or 30.The resolver according to any one of claims 1 to 4, wherein a number of pole pairs of the plurality of excitation windings (22) is M, which is an integer greater than or equal to 1, wherein a number of the salient poles (31) is N, which is an integer greater than or equal to 1, wherein spatial distributions of a number of turns of the first windings and the second windings are respectively obtained from a sum of functions expressed by a sine wave of a (|M±N|)-th spatial order and functions expressed by a sine wave of a (|M-|M±N|)-th spatial order, wherein the sine wave of the (|M-|M±N|)-th spatial order has an amplitude, which is equal to an amplitude of the sine wave of the (|M±N|)-th spatial order, wherein the number of pole pairs M of the plurality of excitation windings (22) is 15, and wherein the number of salient poles (31) N is 10 or 20.The resolver according to any one of claims 1 to 6, wherein the first detection winding group (23) and / or the second detection winding group (24) comprises forward windings that are the detection windings wound in a forward direction and reverse windings that are the detection windings wound in a reverse direction, and wherein a total number of turns of the forward windings and a total number of turns of the reverse windings are equal to each other.The resolver according to any one of claims 1 to 7, wherein the detection stator (2) further comprises a non-magnetic body (30) disposed between the plurality of excitation windings (22) and the plurality of teeth (27), and between the detection windings (231, 241) and the plurality of teeth (27), and wherein the non-magnetic body (30) comprises a separation portion (301) disposed between the excitation winding (22) and the detection winding (231, 241) wound around the same tooth (27).A rotating electric machine, comprising: a stator (102); a rotor (103) rotatable relative to the stator (102); and the resolver (1) according to any one of claims 1 to 8, wherein the detection rotor (3) rotates integrally with the rotor (103).An elevator hoisting machine comprising: a motor (131) comprising: a stator (102); a rotor (103) rotatable relative to the stator (102); and the resolver (1) according to any one of claims 1 to 8; and a drive roller (132) rotated together with rotation of the rotor (103), wherein the detection rotor (3) is rotated (103) unitarily with the rotor.

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