JP5467840B2 - Permanent magnet motor - Google Patents

Description

  The present invention relates to a permanent magnet motor, and in particular, from a combination of 12 slots, 10 poles and an integral multiple of the number of slots and the number of poles using a concentrated winding coil (a coil wound directly around a tooth through an insulator). Related to permanent magnet motors.

  As a conventional motor, in a concentrated winding motor using concentrated winding coils, a stator is obtained by punching an electromagnetic steel plate into a cross-sectional shape of the stator to obtain a stator steel plate, and stacking a plurality of stator steel plates thus obtained. In order to increase the utilization rate of the electromagnetic steel sheet of the stator core, the stator core is divided into a plurality of cores (hereinafter, each one is referred to as a stator core), and the same as described above for each stator core. A technique has been proposed in which a stator core is formed by stacking electromagnetic steel sheets using a technique, and the stator cores are joined in a closed ring shape in an array (see, for example, Patent Document 1).

  According to such a method, the shape of the portion punched by the magnetic steel sheet is the same as the cross-sectional shape of the stator core, and a part of the side forms a part of the circumference. When a stator is made by punching an electromagnetic steel sheet in the entire shape, the electromagnetic steel sheet in the annular inner circular portion is completely wasted, whereas the above method eliminates the waste of such an electromagnetic steel sheet. Can do.

  In the above Patent Document 1, in an 18-slot stator, the stator is divided into 6 (= 18 ÷ 3) so that the number of teeth of each stator core is 3, and a stator including 6 stator cores is provided. A concentrated winding motor is shown.

  Further, as another conventional example, core pieces are created for each tooth, and these are connected to form a divided iron core made up of a predetermined number (for example, six) of teeth. There is also known a technique for forming (see, for example, Patent Document 2).

Japanese Patent Laid-Open No. 2002-233122 JP-A-2004-274970

  Patent Document 1 describes an 18-slot, 12-pole three-phase motor, in which concentrated winding coils of different phases are attached to sequential teeth of the stator core, and concentrated winding coils of the next phase are mounted on adjacent teeth. The structure is arranged. For this reason, when the stator core is divided into three teeth divided cores, one UVW phase coil is combined with each partial core. Accordingly, the phases at both ends of the split core are any two of the UVW phases, and the central phase is a specific one of these three phases.

  For example, when a V-phase coil is arranged on the center tooth of the stator core, in this stator core, a U-phase coil is arranged on one side of the V-phase coil, and a W-phase coil is arranged on the other side. It will be.

  FIGS. 9A and 9B are views showing a part of a stator comprising such a stator core, wherein 1 is a stator, 2a to 2d are stator cores, 3 are teeth, 4 is a coil, 5 is a slot, and 6 is divided. Part.

  9 (a) and 9 (b), the stator cores 2a to 2d forming the stator 1 have three teeth 3, and one coil 4 for each tooth 3 has a U phase, a V phase, They are provided in the order of the W phase (hereinafter referred to as a U phase coil, a V phase coil, and a W phase coil). The stator cores 2a to 2d are annularly arranged and joined in this order to form the stator 1. Therefore, the joint portions (and thus the stator split portions 6) of the stator cores 2a to 2d are between the U-phase coil and the W-phase coil of the stator 1.

  Therefore, when a magnetic flux is generated in the U-phase coil, the magnetic flux passes through both adjacent W-phase coils and U-phase coils as indicated by solid arrows in FIG. It does not pass through the divided portion 6 between (a general term for the stator cores 2a to 2d). On the other hand, if a magnetic flux is generated in the W-phase or U-phase coil provided at both ends of the stator core 2, for example, if a magnetic flux is generated in the U-phase coil, it is indicated by a solid line arrow in FIG. Thus, since this magnetic flux passes through the W phase and V phase adjacent to both sides of the U-phase coil, a part of the magnetic flux, that is, the magnetic flux flowing in the adjacent W-phase coil in FIG. Will also pass.

  By the way, although this division part 6 is a junction part of the adjacent stator core 2, it is devised so that these adjacent stator cores 2 may be closely contacted so as to minimize the magnetic resistance at this junction part. It is impossible to make the gap of zero completely zero. In addition, in consideration of manufacturability as an industrial product, a certain amount of air gap may be allowed in consideration of variations in the stator core 2. Therefore, conventionally, when a magnetic flux is generated in the W-phase coil, a part of the magnetic flux passes through the dividing portion 6, so that the magnetic flux decreases due to the influence of the dividing portion 6.

  The above is the same when magnetic flux is generated in the U-phase coil.

  FIG. 10 is a cross-sectional view showing another example of a stator of a conventional permanent magnet motor, and parts corresponding to those in FIG. Note that “+” and “−” in each layer indicate that the winding direction of the coil 5 in the teeth 3 is reversed.

  In this conventional example, the stator 1 is divided into eight stator cores 2a to 2h. U + and U− U-phase coils, V + and V− V-phase coils, W + and W− Six coils of phase coils are provided, and there are 48 (= 8 × 6) slots.

  In such a stator 1, as shown in the figure, split portions 6 are provided between the W + phase coil and the U + phase coil and between the W− phase coil and the U− phase coil. The dividing part 6 exists only between the coil and the U-phase coil. For this reason, the magnetic flux generated from the V-phase coil (V +, V− phase coil) is not affected by the dividing unit 6, but the magnetic flux generated by the W-phase coil and the U-phase coil is generated by the dividing unit 6. Will be affected. Therefore, when the magnetic flux is unbalanced between the V phase and the U and W phases, the induced voltage decreases in the U phase and W phase by the amount of the reduced magnetic flux compared to the induced voltage due to the V phase magnetic flux. As a result, torque ripple occurs in the permanent magnet motor.

  In the technique described in Patent Document 2, since the stator is created by connecting the core pieces for each tooth, the magnetic flux generated in all the coils is attenuated by the connecting portion.

  Further, in the technique described in Patent Document 2, as a combination of a rotor having 24 poles, 30 poles, 40 poles, 42 poles, and 48 poles with respect to a 36 slot stator, the split seam is deformed upon splitting the stator. The number of divisions is selected so that the distortion mode, that is, the number of divisions, and the torque ripple mode, that is, the number of slots and the greatest common divisor of the number of poles do not match. However, there is no definition of the relationship between the division position and the phase of the stator coil.

  As described above, in the case of the above-described conventional example, compared to the case where the magnetic flux is generated in the V-phase coil, the magnetic flux is reduced in order to generate the magnetic flux in the other U-phase and W-phase coils. As a characteristic of the motor, the torque is reduced. Therefore, the torque decreases once in a half cycle, and this result appears as a torque ripple.

  An object of the present invention is to provide a permanent magnet motor that solves such a problem, reduces the influence of a decrease in magnetic flux due to a split portion between stator cores, and can suppress the occurrence of torque ripple.

In order to achieve the above object, the present invention provides a permanent magnet motor having a stator in which concentrated winding coils are provided in a plurality of slots in three phases, and a rotor provided with a plurality of permanent magnets facing the stator. The number of teeth of the minimum unit of the stator constituting the three phases is 3n (where n is an integer of 1 or more and the number of coils corresponding to 1), and the stator includes a plurality of teeth having the same number of teeth is equally divided by the stator core, the number of teeth in the stator core is (k × 3n) ± n (where, k is an integer of 1 or more) Ri der, number of coils per phase of the stator core is a 2, respectively The coils of the phase are composed of two coils with different winding directions in the teeth, the two coils of the same phase are attached to adjacent teeth, and the rotor is paired simultaneously with the joint portion of the stator core. The rotor core is divided into a plurality of rotor cores so as to face one place, and the number of poles of the rotor core is a multiple of two.

  Further, the present invention is characterized in that the rotor is disposed outside the stator, and a rectangular permanent magnet is disposed on the surface of the rotor facing the stator.

  According to the present invention, the magnetic flux generated by the coils of each phase can be made to uniformly pass through the divided portion of the stator without being biased to the specific phase, and the magnetic flux can be reduced in the specific phase. It is possible to suppress the occurrence of torque ripple due to.

FIG. 1 is a sectional view showing a first embodiment of a permanent magnet motor according to the present invention. It is sectional drawing which shows the specific structure of the stator in FIG. It is sectional drawing which shows the stator of 2nd Embodiment of the permanent magnet motor by this invention. It is sectional drawing which shows the stator in 3rd Embodiment of the permanent magnet motor by this invention. It is sectional drawing which shows the stator of 4th Embodiment of the permanent magnet motor by this invention. It is sectional drawing which shows the stator of 5th Embodiment of the permanent magnet motor by this invention. It is sectional drawing which shows the stator of 6th Embodiment of the permanent magnet motor by this invention. It is a figure which shows the example of the combination of the number of stator cores with respect to the stator of various pole numbers and the number of slots, and the number of slots (coils). It is a figure which shows a part of stator which consists of a stator core. It is sectional drawing which shows the other example of the stator of the conventional permanent magnet motor.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view showing a first embodiment of a permanent magnet motor according to the present invention, wherein 7 is a rotor, 8a to 8e are rotor cores, 9 is a permanent magnet, and 10 is a divided portion, similar to the previous drawings. 1 is a stator, 2a to 2f are stator cores, 3 are teeth, 4 is a coil, 5 is a slot, and 6 is a divided portion.

  In this figure, this embodiment is an abduction type permanent magnet motor in which the rotor 1 is disposed outside the stator. The rotor 1 is divided into a plurality of, in this case, five rotor cores 8a to 8e, and these are arranged in an annular shape and joined together. Permanent magnets 9 are provided on the inner surface of the rotor 1, and thus on the surfaces of the rotor cores 8 a to 8 e facing the stator 1, and each of the rotor cores 8 a to 8 e has eight permanent magnets 9, for a total of 40 permanent magnets 9. Is provided.

  The stator 1 has 48 teeth 3, and therefore 48 slots 5, and a coil 4 is attached to each of the teeth 3. Here, the stator 1 is divided into six stator cores 2a to 2f. Each of the stator cores 2a to 2f is provided with eight teeth 3, and accordingly, coils 4 for each phase.

  Here, in FIG. 1, descriptions of a rotating shaft and bearings that support the rotation of the rotor 7 and the stator 1, a structure such as a motor frame and an end bracket, and electrical parts such as a lead wire and a terminal are omitted. This embodiment forms a concentrated winding permanent magnet motor which is a basic configuration of 40 poles and 48 slots (teeth). Add rotation shafts and bearings that support the rotation of the rotor 7 and the stator 1, structures such as motor frames and end brackets, electrical parts such as lead wires and terminals, etc. When the current is applied, the rotor 7 rotates and functions as a motor.

  FIG. 2 is a cross-sectional view showing a specific configuration of the stator 2 in FIG. 1, and parts corresponding to those in the previous drawings are given the same reference numerals and redundant description is omitted.

  In the figure, each of the six stator cores 2a to 2f is provided with 48 ÷ 6 = 8 teeth 3, and the coils 4 are provided in order from one end to each of the teeth 3. Here, the coil 4 of each phase includes a “+” coil and a “−” coil, and each phase includes two coils 4. That is, the two teeth 3 are used for the coils of the same phase, and the teeth 3 used for the coils of the same phase are adjacent teeth 3.

  Therefore, in each of the stator cores 2a to 2f, two teeth 3 are used in two of the three phases, and four teeth 3 are used for the remaining one phase. Specifically, in the stator core 2a, a U-phase (U +, U-) coil, a V-phase (V-, V +) coil, a W-phase (W +, W-) coil, and a U-phase (U-, U +) coil in this order. In the stator core 2b, the V-phase (V +, V-) coil, the W-phase (W-, W +) coil, the U-phase (U +, U-) coil, and the V-phase (V-, V +) coil are arranged in this order. In the stator core 2c, W-phase (W +, W-) coils, U-phase (U-, U +) coils, V-phase (V +, V-) coils, W-phase (W-, W +) coils are arranged in this order. In the stator core 2f, W-phase (W +, W-) coils, U-phase (U-, U +) coils, V-phase (V +, V-) coils, W-phase (W-, W +) coils are arranged in this order. . According to such an arrangement, the arrangement of the coils 4 of each phase in the opposing stator cores 2a and 2d is equal, the arrangement of the coils 4 of each phase in the opposing stator cores 2b and 2e is equal, and each of the coils in the opposing stator cores 2c and 2f. The arrangement of the phase coils 4 is equal.

  According to the arrangement of the coils 4 of the respective phases, the dividing portion 6 between the stator cores 2a and 2b and between the stator cores 2d and 2e is between the U-phase (U +) coil and the V-phase (V +) coil. The dividing part 6 between 2b and 2c and between the stator cores 2e and 2f is between the V-phase (V +) coil and the W-phase (W +) coil, and the dividing part between the stator cores 2c and 2d and between the stator cores 2f and 2a. 6 is between the W-phase (W +) coil and the U-phase (U +) coil.

  Therefore, the dividing portion 6 in the stator 1 is located between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils, and the U, V, and W phase coils. In any case, the magnetic flux generated by the same number of coils in the U, V, and W phase coils always passes through the dividing section 6. That is, the number of coils that generate magnetic flux passing through the dividing unit 6 is equally distributed in the U, V, and W phases. In FIG. 2, the number of coils that generate magnetic fluxes passing through the dividing section 6 is four for each of the U, V, and W phases. That is, coils that generate magnetic flux passing through the dividing unit 6 are assigned equally to each phase.

  Thereby, when the magnetic flux is generated by the coils of the U, V, and W phases, the magnetic flux generated in the respective phases is equally affected by the dividing unit 6, and in these U, V, and W phases, Magnetic flux decreases by the dividing unit 6 are almost equal, and magnetic flux unbalance between U, V, and W phases does not occur, and torque ripple is suppressed.

  In the first embodiment, the number of the minimum unit teeth 3 (and hence the coils 4) required for the three phases U, V, and W is the same as that of the coils in which the coils 4 in each phase are “+”. Since it is composed of two coils, a “−” coil, 2 × 3 = 6. That is, assuming that the coil 4 of each phase is composed of a set of n coils (where n is an integer of 1 or more), the teeth 3 (therefore, the minimum unit necessary for three phases of U, V, and W phases) The number of coils 4) is 3n, but in this first embodiment, n = 2.

  In the first embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is equally divided into six stator cores 2 (= twice the number of phases 3). Are arranged with coils 4 of four phases (number of phases: 3 + 1). Here, the one-phase coil in this case is a set of a “+” coil and a “−” coil. Forty-eight coils are respectively divided by 48 ÷ 6 = 2 × (number of phases). 3 + 1) = 8 pieces each.

This means that the number of teeth in one stator core 2 is not an integral multiple of the number of minimum unit teeth (and hence coils) required for three phases,
Number of teeth = (k × 3n) ± n (1)
However, k is represented by an integer equal to or greater than 1. In this embodiment, k = 1 and n = 2, and the above equation (1) is 3 × 2 + 2 = 8.

  Thus, in the first embodiment, the torque ripple generated in the conventional permanent magnet motor using the conventional stator 1 is the same 48-slot stator as the conventional stator 1 shown in FIG. Can be reduced.

  FIG. 3 is a cross-sectional view showing a stator of a second embodiment of the permanent magnet motor according to the present invention. The parts corresponding to those in FIG.

  In this figure, in the second embodiment, a permanent magnet motor with 40 stations and 48 slots, as in the first embodiment, the stator 1 is equally divided into 12 stator cores 2a to 2l. A two-phase coil 4 is distributed to one stator core 2. Here, the one-phase coil 4 is composed of a set of a “+” coil and a “−” coil. In terms of the number of coils, each stator core 2 has two phases × 2 = 4 coils. 4 will be distributed.

  Specifically, in the stator core 2a, the coils 4 are arranged in the order of a U-phase (U +, U-) coil and a V-phase (V-, V +) coil. In the stator core 2b, a W-phase (W +, W-) coil, The coils 4 are arranged in the order of U-phase (U−, U +) coils. In the stator core 2c, the coils 4 are arranged in the order of V-phase (V +, V−) coils and W-phase (W−, W +) coils. In the next three stator cores 2d, 2e, and 2f, the coils 4 having the same phase as the stator cores 2a, 2b, and 2c are arranged in the same order. Similarly, the next three stator cores 2g, 2h, and 2i are arranged. However, in the next three stator cores 2j, 2k, 2l, the coils 4 having the same phase as the stator cores 2a, 2b, 2c are arranged in the same order.

  According to the arrangement of the coils 4 for each phase, the divided portions 6 between the stator cores 2a and 2b, between the stator cores 2d and 2e, between the stator cores 2g and 2h, and between the stator cores 2j and 2k are the same V-phase (V +) coil. Between the stator cores 2b and 2c, between the stator cores 2e and 2f, between the stator cores 2h and 2i, and between the stator cores 2k and 2l, the divided portions 6 are between the same U-phase (U +) coil and V. Between the stator cores 2c and 2d, between the stator cores 2f and 2g, between the stator cores 2i and 2j, and between the stator cores 2l and 2a are the same W-phase (W +) coil and U-phase. Between (U +) coils. The division part 6 does not exist in places other than these.

  Therefore, the dividing portion 6 in the stator 1 is located between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils, and the U, V, and W phase coils. In any case, the magnetic flux generated by the same number of coils in the U, V, and W phase coils always passes through the dividing section 6. That is, also in the second embodiment, as in the first embodiment, the number of coils that generate magnetic flux passing through the dividing section 6 is equally distributed in the U, V, and W phases. . In FIG. 3, the number of coils that generate magnetic fluxes passing through the dividing unit 6 is eight for the U, V, and W phases. That is, coils that generate magnetic flux passing through the dividing unit 6 are assigned equally to each phase.

  Thereby, in this 2nd Embodiment, since there are many division | segmentation parts 6 compared with previous 1st Embodiment, the magnetic flux which passes along the division | segmentation parts 6 increases in each phase, and magnetic flux reduces by this. However, as in the first embodiment, when the magnetic flux is generated by the U, V, and W phase coils, the magnetic flux generated in each phase is evenly divided. 6, the decrease of the magnetic flux by the dividing section 6 in the U, V, and W phases is almost equal, and the magnetic flux is not unbalanced between the U, V, and W phases. Torque ripple is suppressed.

  In the second embodiment, the minimum number of teeth 3 (and hence the coils 4) required for the three phases U, V, and W are the same as in the first embodiment. The minimum number of teeth 3 (and hence the coils 4) required for the three W phases is 3n, and n = 2.

  In the second embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is equally divided into twelve stator cores 2 (= four times the number of phases 3). The coils 4 having two phases (number of phases 3-1) are distributed. Here, the one-phase coil in this case is a set of a “+” coil and a “−” coil, and 48 coils are respectively added to the stator core 2 by 48 ÷ 12 = 2 × (number of phases). 3-1) = 4 pieces distributed.

  This means that the number of teeth in one stator core 2 is not an integral multiple of the required number of minimum unit teeth (and therefore coils) of three phases, and this number of teeth is expressed by k = 1, n = 2, and 3 × 2-2 = 4.

  Further, in the second embodiment, the number of divisions of the stator 1 is larger than that of the first embodiment having the same number of poles and slots, and the length of the arc-shaped sides of the respective stator cores 2 in the arrangement direction is long. Therefore, the side portions on the inner surface side and the outer surface side of the stator 1 are closer to a straight line, whereby the utilization rate of the electromagnetic steel plate for punching the steel plate for forming the stator core 2 is further increased. The yield is improved.

  In the second embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is equally divided into twelve stator cores 2 (= number of phases 3 × 4). The coils 4 of two phases (number of phases 3-1) are distributed. Here, the one-phase coil in this case is a set of a “+” coil and a “−” coil, and 48 coils are respectively added to the stator core 2 by 48 ÷ 12 = 2 × (number of phases). 3-1) = 4 pieces distributed.

  Thus, in the second embodiment as well, the conventional stator 1 is used although it is the same 48 slot stator as the conventional stator 1 shown in FIG. The torque ripple generated in the conventional permanent magnet motor can be reduced.

  FIG. 4 is a cross-sectional view showing a stator in a third embodiment of a permanent magnet motor according to the present invention. Parts corresponding to those in the previous drawings are given the same reference numerals and redundant description is omitted.

  In the figure, the third embodiment relates to a 32-pole, 48-slot (tooth) permanent magnet motor, in which the stator 1 is equally divided into six stator cores 2 of stator cores 2a to 2f. . Then, eight (= 48 ÷ 6) coils 4 are distributed to each stator core 2. Here, each of the U, V, and W phase coils is composed of only one type of coil wound in the same direction (here, this is a “+” coil). V and W phase coils are arranged on the stator 1 in the order of “U +” coil, “V +” coil, and “W +” coil.

  Specifically, in the stator core 2a, U, V, and W phase coils are arranged in the order of U +, V +, W +, U +, V +, W +, U +, and V +, and in the stator core 2b, W +, U +, V +, and W +. , U +, V +, W +, U + are arranged in the order of U, V, W phases, and in the stator core 2c, U, V, W in the order of V +, W +, U +, V +, W +, U +, V +, W +. Phase coils are arranged. In the stator core 2d, the arrangement of the U, V, and W phase coils is the same arrangement as that of the stator core 2a. In the stator core 2e, the arrangement of the U, V, and W phase coils is the same arrangement as that of the stator core 2b. In the stator core 2f, the arrangement of the U, V, and W phase coils is the same as that of the stator core 2c.

  According to the arrangement of the coils, the divided portion 6 between the stator cores 2a and 2b and the stator cores 2d and 2e is divided into a V-phase coil (ie, “V +” coil) and a W-phase coil (ie, “W +” coil). There is a division 6 between the stator cores 2b, 2c and between the stator cores 2e, 2f between the U-phase coil (ie, “U +” coil) and the V-phase coil (ie, “V +” coil). The split portion 6 between the stator cores 2c and 2d and between the stator cores 2f and 2a is located between the W-phase coil and the U-phase coil.

The division part 6 does not exist in places other than these.

  Therefore, the dividing portion 6 in the stator 1 is located between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils. Regardless of whether the magnetic flux is generated by any of the V, W, and W phase coils, the magnetic flux generated by the same number of coils in each of the U, V, and W phases always passes through the dividing section 6. . That is, also in the third embodiment, as in the previous embodiment, the number of coils that generate magnetic flux passing through the dividing unit 6 is equally distributed in the U, V, and W phases. In FIG. 4, the number of coils that generate magnetic flux passing through the dividing unit 6 is four in each of the U, V, and W phases, and the coil that generates magnetic flux passing through the dividing unit 6 is equally assigned to each phase.

  As a result, also in the third embodiment, similarly to the first embodiment, when the magnetic flux is generated by the U, V, and W phase coils, the magnetic flux generated in each phase is divided equally. It will be influenced by the part 6, and the decrease of the magnetic flux by the dividing part 6 in the U, V, W phase becomes almost equal, and the magnetic flux unbalance between the U, V, W phase may occur. And torque ripple is suppressed.

  In the third embodiment, the minimum number of teeth 3 (and hence coils 4) required for the three phases U, V, and W is 3n, and n = 1.

  In the third embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is equally divided into six stator cores 2 (= twice the number of phases 3). The coils 4 of 8 phases (2 × number of phases 3 + 2) are distributed. That is, 48 coils are distributed to each stator core 2 by 48 ÷ 6 = 2 × phase number 3 + 2 = 8.

  This means that the number of teeth in one stator core 2 is not an integral multiple of the required number of minimum unit teeth (and therefore coils) of three phases, and this number of teeth is expressed by k = 1, n = 2, and 3 × 2 + 2 = 8.

  In this way, in the third embodiment as well, the conventional stator 1 is used, although it is the same 48-slot stator as the conventional stator 1 shown in FIG. The torque ripple generated in the conventional permanent magnet motor can be reduced.

  FIG. 5 is a cross-sectional view showing a stator of a fourth embodiment of a permanent magnet motor according to the present invention. Parts corresponding to those in the previous drawings are given the same reference numerals and redundant description is omitted.

  In this figure, this fourth embodiment also relates to a 32-pole, 48-slot (teeth) permanent magnet motor, and, like the third embodiment shown in FIG. 4, coils of U, V, and W phases. Is composed of one type of coil “+”, and is repeatedly arranged in the stator 1 in the order of U, V, and W phases. However, as in the third embodiment shown in FIG. 1 is equally divided into 12 stator cores 2a to 2l. Therefore, 48 ÷ 12 = 4 coils 4 are arranged in each stator core 2.

  Specifically, in stator core 2a, coil 4 is arranged in the order of a U-phase (U +) coil, a V-phase (V +) coil, a W-phase (W +) coil, and a U-phase coil. In stator core 2b, V-phase coil, W The coils 4 are arranged in the order of the phase coil, the U phase coil, and the V phase coil. In the stator core 2c, the coils 4 are arranged in the order of the W phase coil, the U phase coil, the V phase coil, and the W phase coil. Then, as in the previous third embodiment, in the next three stator cores 2d, 2e, and 2f, the coils 4 in the same phase as the stator cores 2a, 2b, and 2c are arranged in the same order. In the next three stator cores 2g, 2h, 2i and the next three stator cores 2j, 2k, 2l, the coils 4 having the same phase as the stator cores 2a, 2b, 2c are arranged in the same order.

  According to the arrangement of the coils 4 for each phase, the divided portions 6 between the stator cores 2a and 2b, between the stator cores 2d and 2e, between the stator cores 2g and 2h, and between the stator cores 2j and 2k are the same V-phase coil and W-phase coil. The divided portions 6 between the stator cores 2b and 2c, between the stator cores 2e and 2f, between the stator cores 2h and 2i, and between the stator cores 2k and 2l are between the same U-phase coil and V-phase coil. 2d, the stator cores 2f and 2g, the stator cores 2i and 2j, and the stator cores 2l and 2a are divided between the same W-phase coil and U-phase coil. The division part 6 does not exist in places other than these.

  Therefore, the dividing portion 6 in the stator 1 is located between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils, and the U, V, and W phase coils. In any case, the magnetic flux generated by the same number of coils in the U, V, and W phase coils always passes through the dividing section 6. That is, also in the fourth embodiment, as in the first embodiment, the number of coils that generate magnetic flux passing through the dividing unit 6 is equally distributed in the U, V, and W phases. . In FIG. 5, there are eight coils for generating magnetic fluxes passing through the dividing section 6 for each of the U, V, and W phases. That is, coils that generate magnetic flux passing through the dividing unit 6 are assigned equally to each phase.

  Thereby, in this 4th Embodiment, since the number of the division parts 6 is large compared with the previous 3rd Embodiment, the magnetic flux which passes the division part 6 in each phase increases, and magnetic flux reduces by this. However, as in the first embodiment, when the magnetic flux is generated by the U, V, and W phase coils, the magnetic flux generated in each phase is evenly divided. 6, the decrease of the magnetic flux by the dividing section 6 in the U, V, and W phases is almost equal, and the magnetic flux is not unbalanced between the U, V, and W phases. Torque ripple is suppressed.

  In the fourth embodiment, the number of teeth 3 (therefore, the coil 4) as the minimum unit required for the three phases U, V, and W is the same as that in the third embodiment. The minimum number of teeth 3 (and hence the coils 4) required for the three W phases is 3n, and n = 1.

  In the fourth embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is equally divided into twelve stator cores 2 (= four times the number of phases 3). The coils 4 having four phases (1 × number of phases 3 + 1) are distributed. That is, 48 coils are distributed to each stator core 2 by 48 ÷ 12 = 1 × number of phases 3 + 1 = 4.

  This means that the number of teeth in one stator core 2 is not an integral multiple of the required number of minimum unit teeth (and therefore coils) of three phases, and this number of teeth is expressed by k = 1, n = 1, and 3 × 1 + 1 = 4.

  Further, in the fourth embodiment, the number of divisions of the stator 1 is larger than that of the third embodiment having the same number of poles and slots, and the lengths of the arc-shaped sides of the respective stator cores 2 in the arrangement direction are long. Therefore, the side portions on the inner surface side and the outer surface side of the stator 1 are closer to a straight line, whereby the utilization rate of the electromagnetic steel plate for punching the steel plate for forming the stator core 2 is further increased. The yield is improved.

  Thus, in the fourth embodiment as well, in the same manner as in the first embodiment, the conventional stator 1 is used although it is the same 48-slot stator as the conventional stator 1 shown in FIG. The torque ripple generated in the conventional permanent magnet motor can be reduced.

  FIG. 6 is a sectional view showing a stator of a fifth embodiment of a permanent magnet motor according to the present invention. Parts corresponding to those in the previous drawings are given the same reference numerals and redundant description is omitted.

  In this figure, the fifth embodiment relates to a 30-pole, 36-slot (tooth) permanent magnet motor. Like the first embodiment shown in FIG. 2, U, V, and W-phase coils are used. Is composed of two types of coils having different winding directions of the “+” coil and the “−” coil, and is arranged in the stator 1 in the order of the U, V, and W phases. The embodiment is a combination of stator cores 2 having different numbers of slots (number of coils). Here, the stator 1 is divided into six stator cores 2, but three stator cores 2a, 2b, and 2c having eight coils are arranged in series, and then the coils The configuration is such that three stator cores 2d, 2e, 2f provided with four numbers are arranged in series, and 8 × 3 + 4 × 3 = 36 coils 4 are arranged.

  Specifically, in the stator core 2a, a U phase (U +, U−) coil, a V phase (V−, V +) coil, a W phase (W + and W−) coil, and a U phase (U−, U +) coil in this order. Four-phase coils 4 (a total of eight coils 4) are arranged. In the stator core 2b, a V-phase (V +, V-) coil, a W-phase (W-, W +) coil, a U-phase (U-, U +) In total, eight coils 4 are arranged in the order of coils, V-phase (V-, V +) coils. In the stator core 2c, a W-phase (W +, W-) coil, a U-phase (U-, U +) coil, a V-phase ( A total of eight coils 4 are arranged in the order of V +, V−) coil and W phase (W−, W +) coil. In the stator core 2d, a U phase (U +, U−) coil, a V phase (V−, V +) are arranged. A total of four coils 4 are arranged in the order of the coils. In the stator core 2e, a W-phase (W +, W-) core is provided. In total, four coils 4 are arranged in the order of a coil and a U-phase (U-, U +) coil. In the stator core 2f, a total of four coils are arranged in the order of a V-phase (V +, V-) coil and a W-phase (W-, W +) coil. A number of coils 4 are arranged.

  According to the arrangement of the coils 4 for each phase, the dividing portion 6 is between the U-phase (U +) coil and the V-phase (V +) coil between the stator cores 2a and 2b and between the stator cores 2e and 2f. 2c and between the stator cores 2d and 2e, the dividing part 6 is between the V-phase (V +) coil and the W-phase (W +) coil, and the dividing part 6 is between the stator cores 2c and 2d and between the stator cores 2f and 2a. Between the W-phase (W +) coil and the U-phase (U +) coil. The division part 6 does not exist in places other than these.

  Therefore, also in the fifth embodiment, the dividing portion 6 in the stator 1 is located between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils. Regardless of whether the magnetic flux is generated by any of the U, V, and W phase coils, the magnetic flux generated by the same number of coils always passes through the dividing section 6 for the U, V, and W phase coils. become. That is, as in the first embodiment, the number of coils that generate magnetic flux passing through the dividing unit 6 is equally distributed in the U, V, and W phases. In FIG. 6, the number of coils that generate magnetic flux passing through the dividing unit 6 is four for each of the U, V, and W phases. That is, coils that generate magnetic flux passing through the dividing unit 6 are assigned equally to each phase.

  As a result, also in the fifth embodiment, as in the previous embodiment, when the magnetic flux is generated by the coils of the U, V, and W phases, the magnetic flux generated in each phase is evenly distributed in the dividing unit 6. The decrease in magnetic flux by the dividing portion 6 in the U, V, and W phases is almost uniform, and the magnetic flux is not unbalanced between the U, V, and W phases. Ripple is suppressed.

  In the fifth embodiment, the minimum number of teeth 3 (and hence the coils 4) required for the three phases U, V, and W are the same as in the third embodiment. The minimum number of teeth 3 (and hence the coils 4) required for the three W phases is 3n, and n = 2.

  In the fifth embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is divided into six stator cores 2 (= four times the number of phases 3). 3 is provided with 2 × phase number 3 + 2 = 8 coils (k = 1, n = 2 in the above formula (1)), and the other three are 2 × phase number 3-2 = Four coils 4 (k = 1, n = 2 in the above formula (1)) are provided. This means that the number of teeth in one stator core 2 is not an integral multiple of the required number of minimum unit teeth (and therefore coils) of three phases.

  In the fifth embodiment, in a three-phase (number of phases = 3) permanent magnet motor, the stator 1 is divided into six stator cores 2 (= number of phases 3 × 2), of which three stator cores 8 (= 2 × (number of phases 3 + 1) in 2a to 2c: Here, the numerical value “2” is the number of coils of one phase, ie, four phases), and the remaining three stator cores are arranged. 2d to 2f are four (= 2 × (number of phases 3-1): Here, the numerical value “2” is the number of coils of one phase, that is, two phases).

  In this way, in the fifth embodiment, as in the first embodiment, torque ripple generated in the conventional permanent magnet motor using the conventional stator shown in FIG. 10 can be reduced. it can.

  FIG. 7 is a cross-sectional view showing a stator of a sixth embodiment of a permanent magnet motor according to the present invention. Parts corresponding to those in the previous drawings are given the same reference numerals and redundant description is omitted.

  In the figure, the sixth embodiment relates to a permanent magnet motor having 40 poles and 48 slots (teeth), and the number of slots (number of coils) is different as in the fifth embodiment shown in FIG. The stator core 2 is combined. Here, the U, V, and W phase coils 4 are each composed of only one type of “+” coil, and the stator 1 is divided into nine stator cores 2, but seven coils 4 are provided. Stator cores 2b, 2d, and 2f provided with four coils 4 are arranged between each of the four stator cores 2a, 2c, 2e, and 2g, and four coils 4 are provided between the stator core 2g and the stator core 2a. The two stator cores 2h and 2i provided are arranged, and 7 × 4 + 4 × 5 = 48 coils 4 are arranged.

  Specifically, in the stator core 2a, seven phases of coils 4 are arranged in the order of V phase, W phase, U phase, V phase, W phase, U phase, and V phase, and in the stator core 2b, W phase and U phase. , V phase and W phase are arranged in the order of four phases, and in the stator core 2c, seven phase coils 4 are arranged in the order of U phase, V phase, W phase, U phase, V phase, W phase and U phase. In the stator core 2d, four phase coils 4 are arranged in the order of V phase, W phase, U phase, and V phase. In the stator core 2e, W phase, U phase, V phase, W phase, U phase, V phase are arranged. Seven phase coils 4 are arranged in the order of the phase and the W phase, and four coils 4 are arranged in the order of the U phase, the V phase, the W phase, and the U phase in the stator core 2f. In the next stator cores 2g and 2h, coils of the same phase as the stator cores 2a and 2b are arranged, respectively, and in the last stator core 2i, the coils 4 of the same phase as the stator core 2f are arranged.

  According to the arrangement of the coils 4 of the respective phases, the dividing portion 6 is between the V-phase coil and the W-phase coil between the stator cores 2a and 2b, between the stator cores 2d and 2e, and between the stators 2g and 2h. And between the stator cores 2e and 2f and between the stator cores 2h and 2i, there are split portions 6 between the W-phase coil and the U-phase coil, between the stator cores 2c and 2d, between the stator cores 2f and 2g, and between the stator cores 2i and 2a. The dividing portion 6 is between the U-phase coil and the V-phase coil. The division part 6 does not exist in places other than these.

  Therefore, also in the sixth embodiment, the dividing portion 6 in the stator 1 is equally between the U and V phase coils, between the V and W phase coils, and between the W and U phase coils. Even if the magnetic flux is generated by any of the U, V, and W phase coils, the magnetic flux generated by the same number of coils in each of the U, V, and W phase coils must always pass through the dividing unit 6. Will pass. That is, as in the first embodiment, the number of coils that generate magnetic flux passing through the dividing unit 6 is equally distributed in the U, V, and W phases. In FIG. 7, the number of coils that generate magnetic flux passing through the dividing unit 6 is six for each of the U, V, and W phases. That is, coils that generate magnetic flux passing through the dividing unit 6 are assigned equally to each phase.

  As a result, also in the sixth embodiment, as in the previous embodiment, when the magnetic flux is generated by the coils of the U, V, and W phases, the magnetic flux generated in each phase is evenly distributed in the dividing unit 6. The decrease in magnetic flux by the dividing portion 6 in the U, V, and W phases is almost uniform, and the magnetic flux is not unbalanced between the U, V, and W phases. Ripple is suppressed.

  In the sixth embodiment, in a three-phase permanent magnet motor having 40 poles and 48 slots (number of phases = 3), the stator 1 is divided into nine stator cores 2 (= number of phases 3 × 3), Of the four stator cores 2a, 2c, 2e, and 2f, seven coils 4 (in the above equation (1), 2 × number of phases 3 + 1): where the numerical value “2” is the number of coils in one phase) The four coils 4 are arranged on each of the remaining five stator cores 2b, 2d, 2f, 2h, 2i (1 × 3 + 1 in the above formula (1)). This is the same as in the second embodiment.

  In this way, in the sixth embodiment as well, the torque ripple generated in the conventional permanent magnet motor using the conventional stator shown in FIG. 10 can be reduced as in the first embodiment. it can.

  FIG. 8 is a diagram illustrating an example of combinations of the number of poles, the number of stator cores, and the number of slots (coils) for the stator of the number of slots. The minimum number of slots (coils), Ka and Kb are the number of stator cores, A and B are the number of stator cores, and the number of slots (coils) per stator core in Ka and Kb.

  In FIG. 1, No. 1 2, no. For each combination example, the number of poles P, the total number of slots M of the stator, the number of slots (coils) U of the minimum unit for three phases, the number of stator cores Ka and Kb, the number of stator cores Ka, The number of slots (coils) A and B per stator core at Kb is shown. When all the stator cores 2 have the same number of coils, the number of stator cores is represented by the number of stator cores Ka, and the number of coils is represented by the number of slots (coils) A. In the case of the stator 1 including the stator cores 2 having different numbers of coils, the number of stator cores is represented by the stator core numbers Ka and Kb, and the number of coils in each stator core 2 is represented by the number of slots (coils) A and B.

  Here, when the above embodiment corresponds to FIG. 8, the first embodiment shown in FIG. 9 corresponds to the combination example No. 2 in the second embodiment shown in FIG. It corresponds to 8. The third embodiment shown in FIG. 4 is a combination example No. 1 when the number of slots (coils) U in the minimum unit for three phases is three. In the fourth embodiment shown in FIG. 5, the combination example No. 1 in the case where the number of slots (coils) U of the minimum unit for three phases is three is shown. It corresponds to 8. Further, the fifth embodiment shown in FIG. 7 corresponds to the combination example No. 6 in the sixth embodiment shown in FIG. It corresponds to 20.

  In addition to the embodiments shown in FIGS. 1 to 7, as shown in FIG. 7, the number of stator divisions, that is, the number of stator cores 2 and the above, The number of slots (the number of coils) in the stator core based on the formula (1) is set, whereby the same effect as in the previous embodiment can be obtained.

  In the above description, the number of divisions (that is, the number of rotor cores) of the rotor 7 (FIG. 1) has not been particularly described. However, in consideration of the balance of the polarity, in the rotor core after division, the N pole and the S pole It is appropriate to divide the number of poles into an even number so that the number of the same number matches.

  Moreover, in the said embodiment, although it showed with the outer rotation type motor, the same effect is acquired by performing the same division | segmentation also with the inner rotation type motor by which a rotor is arrange | positioned inside.

  The effect of the present invention is not lost by the difference in the shape of the magnet on the rotor side. The same effect can be obtained even in the magnet embedded type.

  In the present invention, when the core of the stator of the motor is divided, the stator division position is selected so that the influence on a specific phase is not biased. It is suitable for a motor for use in control and position control.

For example, it is suitable for precision industrial machinery and elevator equipment.
[Appendix 1]
A permanent magnet motor having a plurality of polarities and a plurality of slots having a stator in which concentrated winding coils are provided in a plurality of slots in three phases, and a rotor provided with a plurality of permanent magnets facing the stator,
The number of teeth of the smallest unit constituting the three phases is 3n (where n is an integer of 1 or more and the number of coils corresponding to 1),
The stator is divided into a plurality of stator cores, and the number of teeth in the stator core is (k × 3n) ± n (where k is an integer of 1 or more).
A permanent magnet motor characterized by that.
[Appendix 2]
In Appendix 1,
The permanent magnet motor is characterized in that the stator is equally divided by a plurality of stator cores having the same number of teeth.
[Appendix 3]
In Appendix 1 or 2,
In the stator core, n = 2,
A coil of each phase consists of two coils with different winding directions in the teeth, and the two coils of the same phase are attached to the adjacent teeth.
[Appendix 4]
In Appendix 1,
In the stator core, n = 2,
The stator is formed of an array of two types of stator cores having different numbers of teeth.
[Appendix 5]
In Appendix 4,
Of the two types of stator cores having different numbers of teeth, one type of the plurality of stator cores are arranged in series, and after the arrangement of the one type of the stator cores, the other type of the plurality of stator cores are arranged. Permanent magnet motors characterized by being arranged.
[Appendix 6]
In Appendix 4,
A permanent magnet motor, wherein one type of the stator cores and the other type of the stator cores of the two types of stator cores having different numbers of teeth are alternately and continuously arranged.
[Appendix 7]
A permanent magnet motor having a plurality of polarities and a plurality of slots having a stator in which concentrated winding coils are provided in a plurality of slots in three phases, and a rotor provided with a plurality of permanent magnets facing the stator,
12n (where n is an integer of 1 or more) teeth are provided on the stator,
The rotor has a pole number of 10n,
The stator is divided into a plurality of stator cores, and the number of teeth in the stator core is 2
Is not a multiple of 6
A permanent magnet motor characterized by that.
[Appendix 7]
In any one of appendices 1-7,
The rotor is divided into a plurality of rotor cores, and the number of poles of the rotor core is a multiple of two.
[Appendix 8]
In any one of appendices 1-8,
The rotor is disposed outside the stator;
A permanent magnet motor, wherein a rectangular permanent magnet is disposed on a surface of the rotor facing the stator.

DESCRIPTION OF SYMBOLS 1 Stator 2a-2d Stator core 3 Teeth 4 Coil 5 Slot 6 Dividing part 7 Rotor 8a-8e Rotor core 9 Permanent magnet 10 Dividing part

Claims (4)

A permanent magnet motor having a stator in which concentrated winding coils are provided in a plurality of slots in three phases, and a rotor provided with a plurality of permanent magnets facing the stator,
The minimum number of teeth of the stator constituting the three phases is 3n (where n is an integer of 1 or more and the number of coils corresponding to 1),
The stator is divided equally in a plurality of stator cores of equal number of teeth, the number of teeth in the stator core is (k × 3n) ± n (where, k is an integer of 1 or more) Ri der,
The number of coils per phase of the stator core is 2, each phase coil is composed of two coils with different winding directions in the teeth, and the two coils of the same phase are attached to adjacent teeth,
The rotor is divided into a plurality of rotor cores such that a joint portion that faces the joint portion of the stator core at the same time is one, and the number of poles of the rotor core is a multiple of two. The permanent magnet motor according to claim 1,
  The stator is equally divided into six stator cores, each having eight coils, and the rotor is five rotor cores each having eight poles. The permanent magnet motor according to claim 1 or 2 ,
A permanent magnet motor characterized in that coils for generating magnetic flux passing through the joints of the respective stator cores are assigned equally to each phase . In any one of Claims 1-3 ,
The rotor is disposed outside the stator;
A permanent magnet motor, wherein a rectangular permanent magnet is disposed on a surface of the rotor facing the stator.

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