JP2009284626A - Stator of rotating machine and motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem wherein an output is deteriorated because a magnetic path is formed on the entire of a yoke supporting teeth and the magnetic path is short-circuited when a troidally wound coil is applied to a fraction slot multi-pole motor. <P>SOLUTION: The stator of a rotating machine is provided with: a stator core; and a coil wound around the stator core, wherein the stator core is provided with: a yoke; a plurality of teeth provided so as to protrude with a predetermined interval in the circumferential direction from the inner circumference of the yoke; an inner circumferential slot provided on the inner circumference of the yoke sandwiched by adjacent teeth; an outer circumferential slot provided on the outer circumference of the yoke in accordance with the inner circumferential slot; and a magnetic path interrupting portion provided in a diameter direction. The coil is wound using the yoke between the inner circumferential slot and the outer circumferential slot as a winding core, and disposed so that ones having the same phase and different polarity are adjacent in alternating current in a plurality of phases. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a stator of a rotating device that can be suitably used for rotating devices such as a generator and a permanent magnet synchronous motor, and a motor using the stator.

  2. Description of the Related Art Conventionally, a stator for an electric motor including an annular yoke, a plurality of teeth provided on the yoke, and a plurality of coils in which the yoke is toroidally wound is known (for example, Patent Document 1). In this stator, the coil is wound around a yoke portion that exists between adjacent teeth. The coil is connected in a three-phase star or delta shape.

As a brushless DC motor having a coil for three-phase alternating current, as shown in Patent Document 2, a fractional slot multi-pole motor configured so that adjacent in-phase coils form magnetic poles of opposite polarity is known. ing.
JP 2001-37133 A Japanese Patent Laid-Open No. 11-98791

  By the way, it is considered to apply the former toroidal coil described above to the latter fractional slot multipole motor. In this case, a magnetic path is formed between the adjacent partial yokes, teeth and rotors of the stator by coils having the same phase and opposite polarity. At this time, a magnetic path is also formed for the entire yoke that supports the teeth.

  However, if a magnetic path is formed in the entire yoke in this way, the magnetic path is short-circuited against unbalanced magnetomotive force due to variations in coil characteristics and differences in current flowing through the coil. Magnetic flux that does not contribute to the generation of the magnetic field occurs, causing magnetic saturation of the yoke, resulting in a decrease in output.

  Therefore, the present invention aims to eliminate such problems.

  That is, the stator of the rotating device according to the present invention is a stator of a rotating device including a stator core and a coil wound around the stator core, and the stator core is spaced from the yoke by a predetermined interval in the circumferential direction from the inner peripheral side of the yoke. A plurality of teeth provided so as to protrude, an inner peripheral slot provided on the inner peripheral side of the yoke sandwiched between adjacent teeth, and an outer peripheral slot provided on the outer peripheral side of the yoke corresponding to the inner peripheral slot The coil is wound around a yoke between the inner peripheral slot and the outer peripheral slot as a winding core, and has the same phase and different polarity in a plurality of phases of alternating current. Are arranged adjacent to each other.

  According to such a configuration, since the magnetic path blocking portion is provided in the radial direction, when a voltage is applied to the coil, the magnetic path generated in the circumferential direction of the yoke is blocked by the magnetic path blocking portion. Therefore, the magnetic flux caused by the unbalanced magnetomotive force due to the variation in coil characteristics and the difference in current flowing through the coil does not circulate around the yoke. As a result, it is possible to suppress a decrease in torque, and it is possible to suppress the occurrence of vibration and noise due to torque fluctuations. Further, since the coil is wound around the yoke between the inner peripheral slot and the outer peripheral slot formed between the teeth, the yoke diameter can be reduced.

  In the present invention, the rotating device includes a motor or an electric motor and a generator.

  The motor of the present invention is disposed rotatably in the stator of the rotating device and in the stator, S magnetic poles and N magnetic poles are alternately arranged in the circumferential direction, and the number of poles is the number of teeth of the stator. And a rotor having a number larger than 2/3 of the above.

  According to such a configuration, by setting the number of rotor poles to a number larger than 2/3 of the number of teeth of the stator, the coil is wound around the yoke between the inner peripheral slot and the outer peripheral slot formed between the teeth. Despite the concentrated winding coil, a magnetic flux distribution with a small high-frequency component can be obtained. Therefore, torque pulsation can be reduced as compared with the conventional one having concentrated coils.

  The stator of the rotating device of the present invention has the configuration as described above, can suppress a decrease in torque, and can suppress generation of vibration and noise due to torque fluctuation. In addition, the motor of the present invention can obtain a magnetic flux distribution with a small high-frequency component even though it is a concentrated winding coil wound around the yoke between the inner and outer slots formed between the teeth. Therefore, torque pulsation can be reduced as compared with the conventional one having concentrated coils.

  Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

  As shown in FIG. 1, a motor 100 that is a rotating device according to an embodiment described below is a fractional slot multipole motor for three-phase alternating current, and is arranged rotatably in the stator 1 and the stator 1. In this configuration, S magnetic poles and N magnetic poles are alternately arranged in the circumferential direction, and the number of poles is larger than 2/3 of the number of teeth 2 of the stator 1. In this embodiment, the number of teeth 2 of the stator 1 is 12, and the number of poles of the rotor 3 is 14. The rotor 3 includes a rotor iron core 4 and a permanent magnet 5 serving as a magnetic pole fixed to the surface of the rotor iron core 4.

  The stator 1 includes a stator core 6 and a coil 7 wound around the stator core 6. In FIG. 1, the coil 7 is schematically illustrated, and details are shown in FIG. The stator core 6 is adjacent to an annular yoke 8 and a plurality of teeth 2 that protrude from the inner peripheral side of the yoke 8 toward the central portion, that is, the inner side of the yoke 8 and that are provided at predetermined intervals in the circumferential direction. An inner peripheral side slot 9 provided on the inner peripheral side of the yoke 8 sandwiched between the teeth 2 and an outer peripheral side slot 10 provided on the outer peripheral side of the yoke 8 corresponding to the inner peripheral side slot 9 are provided in the radial direction. And a slit 11 as a magnetic path blocking portion. The yoke 8 and each tooth 2 are integrally formed. Each of the teeth 2 includes a tooth flange 2b that connects adjacent teeth 2 at an end facing the rotor 3 on the side opposite to the yoke 8, that is, a rotor-side end 2a. The outer peripheral side slot 10 has substantially the same depth as the diameter of the electric wire 12 constituting the coil 7 at the outer peripheral portion of the yoke 8 between the line segments extending from the substantially central position in the width direction of the tooth 2 when viewed from the front. Formed.

  In the stator 1 of this embodiment, each slit 11 is hollow, and from the front end of the tooth 2, that is, the vicinity of the rotor side end portion 2a, at a substantially central position in the width direction of the tooth 2 when viewed from the front. A length extending in the vicinity of the outer periphery of the yoke 8 is provided. That is, the slit 11 is provided so as to be positioned between the adjacent coils 7 so that a magnetic path that is short-circuited via the teeth 2 and the yoke 8 is not formed.

  As shown in FIG. 3, the yoke 8 around which the coil 7 is wound has an inverted trapezoidal cross-sectional shape in the direction in which the electric wire 12 of the coil 7 is wound. That is, the depth dimension (dimension in the rotation axis direction of the motor 100) of the outer peripheral part of the yoke 8 is larger than the depth dimension of the inner peripheral part. The cross-sectional shape of the yoke 8 is formed so that the outer surface of the coil 7 wound around the yoke 8 is substantially flat on the front side and the back side of the stator 1. That is, the electric wires 12 constituting the coil 7 overlap at the inner peripheral side slot 9 and also overlap at the front side and the rear side between the inner peripheral side slot 9 and the outer peripheral side slot 10. Considering the overlapping state of the electric wires 12, the depth dimension of the yoke 8 of the stator 1 on the inner peripheral side slot 9 side is such that, for example, the outer shape of the coil 7 is formed in a state where three electric wires 12 are overlapped. In addition, the depth dimension of the outer peripheral side slot 10 is set so that the outer side of the coil 7 is formed with one electric wire 12.

  The coil 7 is wound around the yoke 8 between the inner peripheral side slot 9 and the outer peripheral side slot 10, and is arranged adjacent to each other with the same phase and different polarity in a plurality of phases of alternating current. That is, in the coil 7, the U + phase and the U− phase of the three-phase alternating current are arranged adjacent to each other in a pair, and similarly, the V + phase and the V− phase are adjacently paired, and further the W + phase. And W-phase are adjacently arranged in pairs. In FIG. 1, when the rotor 3 rotates counterclockwise, the coils 7 are arranged in the rotation direction in the order of the U phase, the V phase, and the W phase. As shown in FIG. 2, each coil 7 has a wider winding width in the outer peripheral side of the yoke 8, that is, in the outer peripheral slot 10, than in the inner peripheral side of the yoke 8, that is, in the inner peripheral slot 9. And the winding thickness in the outer peripheral side slot 10 is thinner than the winding thickness in the inner peripheral side slot 9.

  In such a configuration, the stator core 6 constituting the stator 1 is obtained by mixing a powder of a soft magnetic material such as iron, silicon steel, and permalloy in a synthetic resin such as an unsaturated polyester or a two-component mixed epoxy resin. The fluid 13 is poured into the stator mold 14 and cured (FIG. 4). In FIGS. 4 and 5, reference numerals of portions corresponding to the stator core 6 after the fluid 13 is cured are shown in parentheses. The stator forming mold 14 is, for example, a mold that can be divided into two in the thickness direction, and includes a drawing mold portion for forming the inner peripheral side slot 9 and the slit 11 of the stator core 6 and has a substantially annular shape. It is.

  Specifically, a magnetic field application device 15 having a size corresponding to the rotor 3 of the motor 100 is disposed inside the stator forming mold 14. The magnetic field application device 15 includes a plurality of magnetic field application coils 16 that are alternately opposite in polarity in accordance with the number of teeth of the stator 1 as first magnetic field application means, and a tooth flange 2b of the rotor-side end 2a of the tooth 2. Functions as a part of the first magnetic field applying means by supplying electric power to the pair of neutral magnets 17 of opposite polarity constituting the second magnetic field applying means forming the neutral portion 2c therebetween and the respective magnetic field applying coils 16 Power supply (not shown). Thereafter, the fluid 13 is poured into the stator mold 14. Then, power is supplied from the power source to each magnetic field application coil 16 from the time when the flow of the fluid 13 is completed until the fluid 13 is cured, thereby generating a magnetic field. This magnetic field aligns the soft magnetic powders in the fluid, and the adjacent magnetic field application coils 16 have opposite polarities. The electric power applied to the magnetic field application coil 16 is direct current only for a predetermined time or impulse. In FIG. 5, the position of the neutral magnet 17 is illustrated so that it can be easily grasped. Further, the magnetic field application coil 16 of the magnetic field application device 15 may be constituted by a permanent magnet. In this case, the power source is not necessary. Moreover, the neutral part magnet 17 may be comprised with a coil, ie, an electromagnet.

  While the magnetic field application coil 16 is energized in this way, the soft magnetic powder in the direction of the magnetic field formed by the magnetic field application coil 16 in the uncured fluid 13 that becomes the teeth 2 and the yoke 8 after curing. Align. The magnetic field is formed to have a width larger than the width of the portion that becomes the teeth 2 and a width that does not magnetically short between the portions that become the teeth 2 in the inner peripheral portion (in FIG. Showing magnetic field). However, in the uncured fluid 13 in the portion between the teeth flanges 2 b corresponding to the neutral magnet 17, the neutral magnet 17 forms a magnetic field opposite to the magnetic field formed by the magnetic field application coil 16. Therefore, the soft magnetic powder is not aligned. As a result, when the motor 100 is operated, it becomes difficult for the magnetic flux to pass between the adjacent tooth flanges 2b, and a short circuit of the magnetic flux does not occur.

  Thus, when applying a magnetic field to the uncured fluid 13 using the magnetic field applying means 15, the neutral part magnet is provided, so that the neutral part 2c in which the soft magnetic powder is not aligned between the teeth flanges 2b. Can be formed. By providing such a neutral portion 2c on the teeth flange 2b, it is possible to prevent a short-circuit magnetic path from occurring between the teeth flanges 2b when the motor 100 is operated. Therefore, it can suppress that the characteristic of the motor 100 falls by leakage inductance. In addition, the rotor magnetic flux can be collected by the tooth flange 2b and effectively linked to the coil 7, thereby improving the motor output. In addition to such improvements in electrical characteristics, the rotor-side end 2a of the adjacent teeth 2 is connected by the teeth flange 2b and the neutral portion 2c, so that the respective teeth 2 are not separated, The strength of the stator 1 can be increased, and machining after the fluid 13 is cured is facilitated.

  Thereafter, when the fluid 13 is cured, the energization of the magnetic field application coil 16 is stopped, and the cured fluid 13, that is, the molded stator core 6 is taken out from the stator molding form 14. Thereafter, the coil 7 is formed on the yoke 8 at a portion sandwiched between the inner peripheral slot 9 and the outer peripheral slot 10 of the stator core 6. Each coil 7 is formed by winding a wire 12 having a predetermined thickness a predetermined number of times. The winding method of the coil 7 is toroidal winding, in which the electric wire 12 is placed in the inner peripheral side slot 9 and the outer peripheral side slot 10, and the electric wire 12 is wound around the yoke 8 rather than around the teeth 2. .

  In this case, as shown in FIG. 2, the inner peripheral slot 9 has a smaller inner width than the outer peripheral slot 10, so that the electric wires 12 are overlapped and wound in the inner peripheral slot 9, and the outer peripheral side In the slot 10, the electric wire 12 is wound without being overlapped. The electric wire 12 extends in the same direction (indicated by an arrow in the figure) from one end portion (hereinafter referred to as a winding start side) in the width direction of the inner peripheral side slot 9 toward the other end portion (hereinafter referred to as a winding end side). That is, it winds from the winding start side to the winding end side. And after winding to the winding end side in the inner peripheral side slot 8, the electric wire 12 returns to the winding start side again, and is piled up and wound. Accordingly, the winding start side is overlapped with the one with the earlier winding order at that stage.

  In the motor 100 having the above-described configuration, the coil 7 is provided on the stator 1 by toroidal winding. Therefore, the radial length of the inner peripheral side slot 9 is shortened as compared with the conventional structure in which the coil 7 is wound around the tooth 2. be able to. As a result, the yoke diameter, and hence the diameter of the stator 1, can be reduced, the motor 100 can be reduced in size, and the material of the stator core 6 can be reduced by reducing the yoke diameter, thereby reducing the weight. be able to.

  Further, by toroidally winding the coil 7, a part of the coil 7 is exposed to the outer peripheral portion of the stator 1. In this case, in this embodiment, the coil 7 contributes to reducing the outer diameter of the stator 1 because the electric wires 12 do not overlap in the radial direction in the outer peripheral side slot 10. For this reason, the contact area of the electric wire 12 which comprises the coil 7, and air increases, and can thermally radiate more efficiently. Thus, the motor output can be improved by suppressing the temperature rise of the coil 7 by heat radiation.

  In addition, when the coil 7 is wound around the yoke 8, the coil 7 is wound in one direction from the winding start side to the winding end side. For this reason, when the motor 100 is operated, even if a surge voltage is applied to the coil 7, it is possible to reduce the shared voltage difference between the voltages constituting each electric wire 12, that is, each turn. For this reason, the partial discharge in the coil 7 resulting from such a voltage difference can be suppressed, and the insulation performance of the coil 7 can be improved. Furthermore, as described above, since the cross section of the yoke 8 has an inverted trapezoidal shape, the contact area between the yoke 8 and the coil 7 can be increased, and the heat dissipation effect of the coil 7 can be improved. In addition, the outer diameter of the stator core 6 can be reduced since the depth dimension of the yoke 8 is increased at the outer peripheral portion. Further, since the yoke 8 has an inverted trapezoidal cross section, the protrusion of the coil 7 from the front and rear end faces of the stator core 6 (end face in the rotation axis direction of the motor 100) can be suppressed to a minimum. can do.

  Thus, by improving the insulation performance of the coil 7 by the winding method of the electric wire 12, the coating of the electric wire 12 constituting the coil 7, specifically, a coating such as enamel or polyamideimide can be thinned. Thus, the cost of the electric wire 12 can be reduced. In addition, it is not necessary to sandwich an insulating sheet (insulating paper) between the electric wires 12 to be overlapped (between winding layers). Therefore, compared with the conventional coil, the weight of each coil 7 itself can be reduced, and by extension, the stator 1 can be reduced in weight.

  With respect to such a coil 7, the stator core 6 includes a slit 11 between the coils 7 of each phase. Therefore, a magnetic field generated when the coil 7 is energized can be short-circuited by the slit 11. Absent. Therefore, since there is no decrease in magnetic force due to the short circuit magnetic path, the motor output can be improved. Along with this, vibration can be suppressed.

  In addition, this invention is not limited to the above-mentioned embodiment.

  In the above-described embodiment, the slit 11 serving as the magnetic path blocking portion is provided for each tooth 2. However, the slit 11 may be provided in at least one of the teeth 2. That is, when at least one slit 11 is provided at a position where the magnetic path generated in the circumferential direction of the yoke 8 is cut off and the magnetic path that short-circuits the yoke 8 is prevented when the coil 7 is energized, the number Is not limited. Moreover, the slit 11 does not necessarily need to be hollow, and the slit 11 may be filled with a nonmagnetic material having a magnetic permeability equivalent to that of air.

  The stator core 6 may be formed by stacking a dust core formed by applying pressure to a non-magnetic material or a steel plate such as a silicon steel plate. In addition, the stator core may be formed into an annular stator core by connecting a plurality of cores serving as a unit with the portion between the slits 11 in the above embodiment as a unit. In this case, a slit may be formed between the cores as a unit, or a nonmagnetic material may be sandwiched between them.

  In the motor 100 according to the above-described embodiment, the rotor 3 having the magnetic poles provided on the surface has been described. However, a permanent magnet embedded rotor in which the magnetic poles are embedded in the rotor core constituting the rotor 3 may be used.

  Further, when the stator core 6 is manufactured, the respective coils 7 are prepared in advance, arranged at predetermined positions in the above-described stator molding mold 14, and the fluid 13 is placed in the stator molding mold 14 in this state. It may be produced by pouring it into. In this case, since the components other than the coil 7 are the same as those described in the above embodiment, description thereof will be omitted.

  First, a required number of coils corresponding to the above-described coil 7 are manufactured, and the coils are arranged at positions in the stator molding form corresponding to the portions to be the yokes of the stator. And the fluid which mixed the synthetic resin and the soft magnetic powder is poured until the coil is immersed in the mold for stator molding in which the coil is arranged. Until the fluid is cured, magnetic flux is applied by the magnetic flux applying means to align the soft magnetic powder. After the fluid has hardened, the operation of the magnetic flux applying means is stopped, and the stator forming mold is disassembled to complete the stator.

  The coil may be formed by being hardened with an insulating varnish or a resin molding material, or housed in a resin bobbin. Further, the coils may be mechanically coupled to each other before positioning the fluid.

  In such a stator manufacturing method, in addition to the slit, the magnetic path blocker has a non-magnetic material placed in the stator molding form at that position, and when the fluid is cured, the magnetic path blocker becomes the stator core. It may be integrally formed inside.

  In this way, the coil is prepared in advance, and the coil is integrated with the stator core so that the fluid is hardened so that it is integrated with the stator core. Can be improved. Since the stator core is formed of a fluid made of a synthetic resin mixed with soft magnetic powder, a highly accurate press sheet metal is not required, and manufacturing equipment costs can be reduced.

  In addition, the coil in the modification of the above-mentioned embodiment and manufacturing method may use a rectangular wire with a square cross-sectional shape.

  In addition, the specific configuration of each part is not limited to the above embodiment, and various modifications can be made without departing from the spirit of the present invention.

  As an application example of the present invention, it can be used in a permanent magnet synchronous motor.

BRIEF DESCRIPTION OF THE DRAWINGS The structure explanatory drawing which shows the motor of embodiment of this invention. The figure which shows the winding state of the coil of the embodiment. Sectional drawing of the yoke of the embodiment. Structure explanatory drawing which shows the manufacturing apparatus of the stator core of the embodiment. Explanatory structure explanatory drawing which expands and shows the corresponding | compatible part of the teeth flange in the manufacturing apparatus of the stator core of the embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Stator 2 ... Teeth 2b ... Teeth flange 3 ... Rotor 6 ... Stator core 7 ... Coil 8 ... Yoke 9 ... Inner peripheral side slot 10 ... Outer peripheral side slot 11 ... Slit 12 ... Electric wire 13 ... Fluid 14 ... Form for stator molding 15 ... Magnetic field application device

Claims (2)

A stator of a rotating device comprising a stator core and a coil wound around the stator core,
The stator core is the yoke,
A plurality of teeth provided protruding from the inner peripheral side of the yoke in the circumferential direction at a predetermined interval;
An inner peripheral slot provided on the inner peripheral side of the yoke sandwiched between adjacent teeth;
An outer peripheral slot provided on the outer peripheral side of the yoke corresponding to the inner peripheral slot;
A magnetic path blocking portion provided in a radial direction,
A coil is a stator for a rotating device in which a yoke between an inner peripheral slot and an outer peripheral slot is wound around a core, and coils having the same phase and different polarity in an alternating current of a plurality of phases are arranged adjacent to each other. A stator of the rotating device according to claim 1;
A motor including a rotor that is rotatably arranged inside a stator, alternately arranged with S magnetic poles and N magnetic poles in the circumferential direction, and whose number of poles is larger than 2/3 of the number of teeth of the stator.

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