JP2005086879A - Stator structure of motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the motor characteristics of a multi-phase motor and a 2Y motor. <P>SOLUTION: The stator structure of the motor comprises a rotor, which generates a magnetic field flux and a stator where a plurality of pairs of stator coils in a plurality of phases that generate a rotating magnetic field for rotating the rotor are wound on a stator core. By eliminating the overlapping of rotor coils, the interference between coils is suppressed, resulting in a symmetrical torque which is applied to the rotating shaft of the motor, to prevent the wobbling of the rotary shaft of the motor. By suppressing unbalance between UVW phases instead of permitting the overlapping of the rotor coils, self-inductance can be uniformized. As a result, current controllability is improved. These can be applied to both the multi-phase motor and the 2Y motor. In another mode, by devising an arrangement of an armature winding for interlinking the teeth, the magnetic flux generated at the armature winding is cancelled each other. So, the current of zero-phase that flows the armature winding which interlinks the teeth, which is a problem specific to the 2Y motor, can be removed. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a stator structure of a motor, in particular, a stator such as a multiphase motor having a large number of phases in one motor or a motor having two Y-connected three-phase coils (hereinafter referred to as a 2Y motor). The present invention relates to an improvement in the winding structure of a stator coil applied to.

  Rotating electric machines such as induction motors and DC motors are widely used as power sources for industrial or vehicle use. As a coil layout of a stator in this type of rotating electric machine, distributed winding having a high specific output is generally adopted. This distributed winding is a winding method in which a coil is wound across a plurality of teeth, and has a structural feature that coils of each phase overlap.

  In addition, as this kind of stator structure, what has a structure as shown in the following patent document 1 is known. In the stator disclosed in Patent Document 1, the selection range of the number of coil wires constituting the armature winding A1 and the armature winding B1, which are different windings, is one pole per phase or adjacent (P / 2-1) It is a pole segment. By complying with this selection range, the armature winding A and the armature winding B can always have at least a region that does not overlap between the same phases. Interference is reduced.

JP 2001-275322 A

  However, the stator structure shown in Patent Document 1 employs distributed winding in which the respective windings (windings A1, A2 and B1, B2) are wound in an overlapping manner. Therefore, although the magnetic mutual interference between the armature windings A and B is reduced at least between the same phases, since the overlapping between the armature windings A and B occurs, the magnetic mutual interference is completely achieved. There is a problem that the generation of large current ripples superimposed on the phase current and mechanical vibrations cannot be completely prevented.

  In addition, when the invention disclosed in Patent Document 1 is applied to a 2Y motor, an inappropriate magnetic field is generated by a zero-phase current that moves back and forth between the power sources arranged between the neutral points. There is a problem of causing a drop and distortion of the phase current.

  The present invention has been made in view of the above problems, and an object thereof is to provide a stator structure capable of improving motor characteristics in both a multiphase motor and a 2Y motor.

  In order to solve the above-described problems, a stator structure of a motor according to the present invention includes a rotor that is a field magnetic flux generation source and a multi-phase stator coil that generates a rotating magnetic field that rotates the rotor. A stator structure in a motor including a stator wound around a plurality of sets of stator cores, wherein the plurality of sets of stator coils do not overlap each other at a mechanical angle of 360 °. Thus, mutual interference between each set of stator coils is suppressed.

  In another stator structure of a motor according to the present invention, a rotor that is a field magnetic flux generation source and a multi-phase stator coil that generates a rotating magnetic field that rotates the rotor are wound around a plurality of sets of stator cores. A stator structure in a motor including a stator configured by being rotated, wherein the plurality of sets of stator coils have an electrical angle that overlaps each other at a mechanical angle of 360 ° so that the electrical angle is 360 ° or less. It is wound around the iron core, and this is characterized in that mutual interference between the stator coils of each group is suppressed.

  The stator structure of another motor according to the present invention includes a first power source that outputs a DC voltage, a pair of inverters that receive power supply from the first power source, and supply of AC output from the pair of inverters separately. A pair of star-connected stator coils each generating a rotating magnetic field, a second power source connected between the neutral points of the star-connected stator coils and providing a potential difference between the neutral points, and the plurality of sets And a pair of stator coils wound around a stator core without overlapping each other at a mechanical angle of 360 °. Thus, the mutual interference between the pair of star connection stator coils is suppressed.

  Further, another motor stator structure according to the present invention includes a first power source that outputs a DC voltage, a pair of inverters that receive power supply from the first power source, and an AC output from the pair of inverters. A pair of star-connected stator coils each generating a rotating magnetic field, and a second power source connected between the neutral points of the star-connected stator coils and providing a potential difference between the neutral points; A pair of stator coils corresponding to the pair of star-connected stator coils, wherein the pair of stator coils have an electrical angle of 360 ° or less that overlaps each other at a mechanical angle of 360 °. It is wound around the stator core so that the mutual interference between the pair of star-connected stator coils is suppressed.

  The stator structure of another motor according to the present invention includes a first power source that outputs a DC voltage, a pair of inverters that receive power supply from the first power source, and supply of AC output from the pair of inverters. A pair of star-connected stator coils that are separately received and each generate a rotating magnetic field; a second power source that is connected between neutral points of the star-connected stator coils and applies a potential difference between the neutral points; A plurality of teeth around which the stator coils are wound, and each tooth includes the pair of stars. A part of the connection stator coil is wound respectively, and another star connection stator coil is set such that zero phase currents in opposite directions flow.

  Further, another stator structure of the motor according to the present invention includes a rotor core that is a field magnetic flux generation source and a plurality of sets of stator cores including a star connection stator coil that generates a rotating magnetic field that rotates the rotor. A stator structure in a motor including a stator wound around a plurality of teeth around which the stator coil is wound, and each of the teeth includes the plurality of sets of star connection stators. A part of the coil is wound in an overlapping manner, and another set of star-connected stator coils is set so that the opposite side is a neutral point in the circumferential direction.

  When one aspect of the present invention is applied to a multiphase motor, there is almost no mutual interference between the windings, so that the torque applied to the motor rotation shaft is symmetric and the shaft runout of the motor rotation shaft can be suppressed. . Further, it is possible to suppress a large current ripple superimposed on the phase current generated when there is mutual interference between the rotor coil connections.

  Further, according to another aspect of the present invention, self-inductance imbalance that occurs as a contradiction to the elimination of the mutual interference of the rotor coils can be suppressed, and current control is achieved by aligning the self-inductance. It becomes possible to improve the property.

  Furthermore, the present invention can also be applied to a 2Y motor, and this invention can provide the same effect as that of a multiphase motor.

  Furthermore, according to another aspect of the present invention, torque drop and distortion of the phase current caused by the zero-phase current flowing through the armature winding interlinked with the teeth, which are problems unique to the 2Y motor, are prevented. Therefore, the motor characteristics can be improved.

  Furthermore, it is possible to apply another aspect of the present invention to a multiphase motor, and according to such an invention, a configuration in which magnetic poles are divided into a plurality of stages in an ordinary multiphase motor reduces leakage inductance. be able to.

  The best mode for carrying out the present invention will be described with reference to the drawings.

Embodiment 1
FIG. 1 is a diagram showing a schematic configuration of a stator structure in the present embodiment. FIG. 1 illustrates an 8-pole (4-pole pair) motor. That is, the stator structure in the present embodiment is configured by winding a rotor that is a field flux generation source and a plurality of stator coils that generate a rotating magnetic field that rotates the rotor around a plurality of sets of stator cores. The present invention is applied to a so-called multiphase motor comprising a fixed stator. In the stator structure of the present embodiment, the armature winding is wound in such a manner that the stator coils are not overlapped with each other.

  The 8-pole (4-pole pair) motor shown in FIG. 1 forms a three-phase UVW phase by windings 1 wound on the upper right and lower left of the page. Similarly, the windings 2 wound on the upper left and lower right of the paper form a three-phase UVW phase. Thus, by eliminating the overlap between the winding 1 and the winding 2, a motor with almost no mutual interference between the stator coils can be realized.

  A specific stator structure will be described with reference to FIGS. 2 (a) and 3 (a) are diagrams for explaining the winding configuration of the winding 1 in FIG. 1, and FIG. 2 (b) and FIG. 3 (b) are the windings in FIG. It is a figure explaining the coil | winding structure of 2. FIG. That is, in order to more clearly show the configuration of the winding 1 and the winding 2, both the windings are illustrated separately. However, in practice, both windings are wound around the same armature core. 2 and 3 differ in how the UVW-phase stator coil is accommodated in a mechanical angle range of 90 °.

  The winding structure shown in FIG. 2 will be described with reference to the winding 1 shown in FIG. 2A. In the clockwise direction from the top of the drawing (U1-V1-V1-W1-W1-U1-U1) -V1-V1-W1-W1-U1) Windings 1 are stored in this order. That is, the U-phase coil 3u is formed by winding an armature winding 8u (winding 1) between two slots 5u and 5u with six teeth 6 therebetween. Similarly, the V-phase coil 3v on the right side of the paper is formed by winding an armature winding 8v (winding 1) between two slots 5v and 5v with six teeth 6 therebetween. . Thereafter, similarly, the W-phase coil 3w is also wound, and the winding 1 is set in a mechanical angle range of 90 °. In addition, the coils 3u, 3v, and 3w of each phase are placed between the teeth 6 in the same phase at positions where the mechanical angles are 180 °. These coils 3u, 3v, and 3w are connected by the crossover wire 7, and the stator coil by the coil | winding 1 is formed.

  On the other hand, the winding structure shown in FIG. 3 will be described using the winding 1 shown in FIG. 3A from the top of the drawing (U1-U1-V1-V1-W1-W1-U1-U1- The windings are stored in the order of V1-V1-W1-W1). 3 is the same as the stator structure shown in FIG. 2 except that the U-phase coil 3u has an armature winding 8u between two slots 5u and 5u with six teeth 6 therebetween. (Winding 1) is formed by winding. Thereafter, the U-phase coil 3u, the V-phase coil 3v, and the W-phase coil 3w are similarly wound, and the winding 1 is set within a range of 90 ° in mechanical angle. In addition, the coils 3u, 3v, and 3w of each phase are placed between the teeth 6 in the same phase at positions where the mechanical angles are 180 °. These coils 3u, 3v, and 3w are connected by the crossover wire 7, and the stator coil by the coil | winding 1 is formed.

  As described above, in any of the stator structures in FIG. 2 and FIG. 3, a plurality of sets of stator coils configured by the winding 1 and the winding 2 do not overlap each other at a mechanical angle of 360 °. Therefore, there is almost no mutual interference between the stator coils of each set.

  Thus, in the stator structure in the present embodiment, the mutual interference between the windings hardly occurs. Therefore, since the torque applied to the motor rotation shaft is symmetric, shaft runout of the motor rotation shaft can be suppressed. In addition, there is an advantage that a large current ripple superimposed on the phase current generated when there is mutual interference between the armature windings can be suppressed.

Embodiment 2
In the first embodiment described above, the stator having a structure in which the winding is wound in a form in which the rotor coils are not overlapped with each other has been described. In this embodiment, instead of allowing the rotor coils to overlap (see FIG. 4), a description will be given of a stator structure that can align self-inductance by eliminating imbalance between the UVW phases. In this embodiment, an 8-pole (4-pole pair) motor (so-called multiphase motor) will be described as an example.

  FIG. 5 is a diagram showing a specific stator structure to which the present embodiment is applied. 5A is a diagram for explaining the winding configuration of the winding 1 in FIG. 4, and FIG. 5B is a diagram for explaining the winding configuration of the winding 2 in FIG. FIG. As shown in FIG. 5, it can be seen that the armature windings 8 u, 8 v, 8 w that connect the rotor coils housed in the teeth 6 are overlapped with each other in the windings 1 and 2. Specifically, for example, referring to the winding 1 shown in FIG. 5A, the armature windings 8v and 8w connecting the V1 phase and the W1 phase protrude from the range of the winding 2 on the right side of the page. I understand.

  However, the stator structure shown in the present embodiment is characterized in that self-inductance is obtained by eliminating imbalance between UVW phases. For example, in the portion indicated by the reference numeral (α) surrounded by the broken-line circle in FIG. 2 described above, the U1 phase armature windings 8u, 8u have portions linked to the same tooth 6. The directions of current flow are opposite to each other. Therefore, the magnetic field is canceled in the U1-phase armature winding 8u, and the self-inductance becomes small in the U1-phase. On the other hand, in the V1 phase and the W1 phase, in the armature windings 8v and 8w interlinked with the same tooth 6, the direction of current flow is the same in the armature windings 8v and 8w of the respective phases. Accordingly, since the self-inductance is smaller in the U1 phase than in the V1 phase and the W1 phase, the self-inductance is not aligned.

  On the other hand, in the stator structure in the present embodiment shown in FIG. 5, for example, as shown in FIG. 5A, armature windings 8 u that interlink with the teeth 6 in each of the U1 phase, the V1 phase, and the W1 phase. Since there is no overlap of 8v and 8w, it can be said that the self-inductance is complete. That is, it can be said that the plurality of sets of stator coils in the present embodiment are wound around the stator core such that the electrical angles that overlap each other at a mechanical angle of 360 ° are 360 ° or less. Therefore, in this embodiment, it is possible to eliminate the self-inductance imbalance that occurs as a contradiction to the fact that the mutual interference between the armature windings 8u, 8v, and 8w is almost eliminated in the first embodiment described above. That is, current controllability can be improved by aligning the self-inductance.

  In the stator structure shown in FIG. 3, the directions of the currents flowing through the armature windings 8u, 8v, 8w linked to the teeth 6 in the U1, V1, and W1 phases are the same. Therefore, even the stator structure shown in FIG. 3 has the same self-inductance, and it can be said that it is more suitable than the stator structure shown in FIG. 2 in terms of improving current controllability.

Embodiment 3
In Embodiment 1 and Embodiment 2 described above, the case where the present invention is applied to a so-called multiphase motor has been described as an example. However, the application of the present invention is not limited to a multiphase motor. For example, the 2Y motor illustrated in FIG. 6 is applicable. FIG. 6 is a diagram showing a schematic configuration of a power output apparatus to which the 2Y motor is applied, and the 2Y motor will be described with reference to this figure.

  A power output apparatus 10 illustrated in FIG. 6 is connected to a motor (2Y motor) 12 having two three-phase coils 14 and 16 that are Y-connected, and two three-phase coils 14 and 16, respectively, and a positive bus 18 Between the neutral points of the two inverter circuits 22 and 24 sharing the negative bus 20, the capacitor 26 connected to the positive bus 18 and the negative bus 20, and the two three-phase coils 14 and 16 of the 2Y motor 12. A DC power supply 28 provided and an electronic control unit (not shown) for controlling the entire apparatus are provided.

  The 2Y motor 12 itself has the same configuration as that of a normal synchronous generator motor capable of generating electric power. To drive such a 2Y motor 12, a three-phase AC voltage applied to the three-phase coil 14 by the inverter circuit 22 is used. In contrast, the inverter circuit 24 may be controlled such that a three-phase AC voltage having a phase difference is applied to the three-phase coil 16. The rotating shaft of the 2Y motor 12 serves as the output shaft of the power output device 10, and power is output from this rotating shaft. Since the 2Y motor 12 in FIG. 6 is configured as a generator motor as described above, the 2Y motor 12 can generate power when power is input to the rotating shaft of the 2Y motor 12.

  Each of the inverter circuits 22 and 24 is composed of six transistors and six diodes. The six transistors are arranged in pairs so as to be on the source side and the sink side with respect to the positive electrode bus 18 and the negative electrode bus 20, respectively, and the three-phase coils 14 and 16 (UVW) of the 2Y motor 12 are connected to the connection points. ) Are connected. Therefore, if the on-time ratio of the paired transistors is controlled according to the phase difference in a state where a voltage is applied to the positive electrode bus 18 and the negative electrode bus 20, the rotating magnetic field is generated by the three-phase coils 14 and 16 of the 2Y motor 12. And the 2Y motor 12 can be rotationally driven.

  The same effect can be obtained by applying the present invention described in the first and second embodiments to the 2Y motor 12 as described above.

Embodiment 4
By the way, as a problem peculiar to the 2Y motor, in the power output apparatus 10, a direct current power supply 28 is placed between two star connections, and a direct current flows from the direct current power supply 28 to the capacitor 26 side. A phenomenon occurs in which magnetic flux is superimposed when current flows through the 2Y motor 12. The present embodiment provides a stator structure capable of satisfactorily suppressing superposition of such magnetic flux. This embodiment will be described with reference to FIGS. Here, FIG. 7 is a diagram illustrating the winding structure in the present embodiment, FIG. 7A is a diagram for explaining the winding configuration of the winding 1, and FIG. FIG. 3 is a diagram for explaining a winding configuration of a wire 2. FIG. 8 is an enlarged view of a part of FIG.

  What is characteristic in the present embodiment is that the rotor coil formed by the armature windings 8 u, 8 v, 8 w is provided in two stages between one tooth 6. Moreover, in the stator structure in the present embodiment, the number of armature windings 8u, 8v, 8w linked to the teeth 6 is always an even number (in FIG. 7 and FIG. 8, it is always 4 or 6). ).

  The reason for this configuration is to solve the problems specific to 2Y motors. That is, in a normal multiphase motor, since the DC power supply 28 is not connected between the neutral points, no zero-phase current flows through the armature windings 8u, 8v, 8w interlinked with the teeth 6. That is, the magnetic flux is not superimposed on the teeth 6 due to the zero-phase current. On the other hand, in the 2Y motor, a zero-phase current flows through the armature windings 8u, 8v, and 8w interlinked with the teeth 6, so that a torque drop occurs due to the superposition of magnetic flux on the teeth 6 due to the zero-phase current, Phase current distortion occurs. Therefore, the motor characteristics are deteriorated.

  Therefore, in this embodiment, a plurality of teeth 6 around which a stator coil is wound are provided, and each tooth 6 is wound with a part of a pair of star-connected stator coils, and another star. The connection stator coils were set so that zero-phase currents in opposite directions would flow. That is, by devising the arrangement of the armature windings 8u, 8v, 8w interlinking the teeth 6, the magnetic flux generated in the teeth 6 by the zero-phase current flowing through the armature windings 8u, 8v, 8w is generated by the armature winding. The lines cancel each other out.

  This will be described in more detail with reference to FIG. 8. The arrows in FIG. 8 indicate the direction of the zero-phase current flowing in the battery provided in the wiring connecting the neutral points of the two motors. The directions of the zero-phase currents flowing in the armature windings 8u, 8v, and 8w indicated by the arrows cancel each other in the even number of armature windings 8u, 8v, and 8w that are linked to the teeth 6. Is flowing. Therefore, the magnetic flux is canceled, and as a result, there is no magnetic flux superposition on the teeth 6. That is, the magnetic field due to the zero-phase current flowing through the neutral point does not remain in the teeth. Although the windings are slightly overlapped, the influence of the one pole pair does not overlap, so the influence is slight.

  The present embodiment is not limited to the configuration shown in FIGS. 7 and 8. For example, the two-stage magnetic pole shown in FIG. 7 is changed to four stages, and the number of teeth 6 is changed in the circumferential direction. Any structure may be used as long as the magnetic field caused by the zero-phase current flowing through the neutral point does not remain in the teeth 6 such as an increased number.

  Further, the stator winding structure in this embodiment can be applied to a multiphase motor. That is, it has a plurality of teeth around which a stator coil is wound, and each tooth has a plurality of sets of star-connected stator coils wound around each other, and another set of star-connected fixings. The child coil preferably has a structure that is set so that the opposite side becomes a neutral point in the circumferential direction. In this way, a plurality of sets of magnetic poles are formed between the teeth by winding another set of armature windings, and the neutral point of each magnetic pole is on the opposite side. This is because no zero-phase current is generated in the motor, but if the magnetic pole is divided into a plurality of stages in an ordinary multi-phase motor, the effect of eliminating leakage inductance can be obtained.

FIG. 3 is a diagram illustrating a schematic configuration of a stator structure in the first embodiment. FIG. 2A is a diagram illustrating a stator structure in the first embodiment, FIG. 2A is a diagram illustrating a winding configuration of a winding 1 in FIG. 1, and FIG. 2B is a winding 2 in FIG. It is a figure explaining the coil | winding structure of this. FIG. 3A is a diagram illustrating a stator structure in the first embodiment, FIG. 3A is a diagram illustrating a winding configuration of the winding 1 in FIG. 1, and FIG. 3B is a diagram illustrating a winding 2 in FIG. It is a figure explaining the coil | winding structure of this. FIG. 5 is a diagram illustrating a schematic configuration of a stator structure in a second embodiment. FIG. 5A is a diagram illustrating a specific stator structure to which the second embodiment is applied, FIG. 5A is a diagram for explaining a winding configuration of the winding 1 in FIG. 4, and FIG. FIG. 5 is a diagram for explaining a winding configuration of a winding 2 in FIG. 4. It is a figure which shows schematic structure of the power output device with which 2Y motor is applied. 7A and 7B are diagrams illustrating a winding structure in a fourth embodiment, FIG. 7A is a diagram for explaining a winding configuration of the winding 1, and FIG. It is a figure for demonstrating. It is the figure which expanded a part of FIG.

Explanation of symbols

  3u U-phase coil, 3v V-phase coil, 3w W-phase coil, 5u, 5v, 5w slot, 6 teeth, 7 crossover, 8u, 8v, 8w armature winding, 10 power output device, 12 2Y motor, 14, 16 three-phase coil, 18 positive bus, 20 negative bus, 22, 24 inverter circuit, 26 capacitor, 28 DC power supply.

Claims (6)

A stator in a motor comprising a rotor that is a field magnetic flux generation source and a stator that is formed by winding a plurality of stator coils that generate a rotating magnetic field that rotates the rotor around a set of stator cores. Structure,
The plurality of sets of stator coils are wound around the stator core without overlapping each other at a mechanical angle of 360 °, thereby suppressing mutual interference between the sets of stator coils. Motor stator structure. A stator in a motor comprising a rotor that is a field magnetic flux generation source and a stator that is formed by winding a plurality of stator coils that generate a rotating magnetic field that rotates the rotor around a set of stator cores. Structure,
The plurality of sets of stator coils are wound around the stator iron core so that the electrical angles overlapping each other at a mechanical angle of 360 ° are 360 ° or less, whereby mutual interference between each set of stator coils is achieved. The stator structure of the motor, wherein the motor is suppressed. A first power source for outputting a DC voltage;
A pair of inverters that receive power from the first power source;
A pair of star-connected stator coils that separately receive supply of AC output from the pair of inverters and generate a rotating magnetic field,
A second power source connected between the neutral points of the star-connected stator coil and providing a potential difference between the neutral points;
One rotor provided corresponding to the plurality of sets of star-connected stator coils;
In a motor system including
The pair of stator coils are wound around a stator core without overlapping each other at a mechanical angle of 360 °, whereby mutual interference between the pair of star connection stator coils is suppressed. Motor stator structure. A first power source for outputting a DC voltage;
A pair of inverters that receive power from the first power source;
A pair of star-connected stator coils that separately receive supply of AC output from the pair of inverters and generate a rotating magnetic field,
A second power source connected between the neutral points of the star-connected stator coil and providing a potential difference between the neutral points;
One rotor provided corresponding to the pair of star connection stator coils;
In a motor system including
The pair of stator coils are wound around the stator core so that the electrical angles that overlap each other at a mechanical angle of 360 ° are 360 ° or less, thereby preventing mutual interference between the pair of star-connected stator coils. The stator structure of the motor is characterized by being suppressed. A first power source for outputting a DC voltage;
A pair of inverters that receive power from the first power source;
A pair of star-connected stator coils that separately receive supply of AC output from the pair of inverters and generate a rotating magnetic field,
A second power source connected between the neutral points of the star-connected stator coil and providing a potential difference between the neutral points;
One rotor provided corresponding to the plurality of sets of star-connected stator coils;
In a motor system including
A plurality of teeth around which the stator coil is wound, each of the teeth is wound with a part of the pair of star-connected stator coils, and the other star-connected stator coils are opposite to each other; A stator structure for a motor, which is set so that a zero-phase current flows. Stator structure in a motor comprising a rotor that is a field magnetic flux generation source and a stator that is formed by winding a plurality of sets of stator-connected stator coils around a stator core that generates a rotating magnetic field that rotates the rotor. Because
The stator coil has a plurality of teeth wound thereon, each of the teeth is overlapped with a part of the plurality of sets of star connection stator coils, and another set of star connection stator coils. Is a stator structure of a motor, characterized in that it is set so that the opposite side becomes a neutral point in the circumferential direction.

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