JP6030610B2 - Rotating electrical iron core - Google Patents

Description

  The present invention relates to an iron core in a rotating electric machine such as an electric motor and a generator. In a rotating electric machine for which higher efficiency has been demanded in recent years, the cogging torque of the rotor of the rotating electric machine has been completely eliminated. TECHNICAL FIELD OF THE INVENTION The present invention relates to a technology for a stator core of a rotating electrical machine that achieves high efficiency, small size, and high output by realizing typical rotational characteristics and improving performance.

  As is well known, reducing the cogging torque of the rotor in the rotating electric machine to achieve stable rotating characteristics is an important factor for improving the characteristics of the rotating electric machine.

  Prior to this patent application, the second harmonic of the fundamental frequency of the cogging torque when the iron core of the rotating electrical machine has the minimum number of magnetic poles, such as 3 poles and 2 poles. Has been disclosed to reduce and smooth the cogging torque. (Patent Document 1)

  That is, the number of stator magnetic poles is a multiple of 3 and the number of magnetic poles is a multiple of 2, and the permanent magnet rotor has no gap between the magnetic poles of the rotor having a sinusoidal orientation. The ratio of the number of stator magnetic poles to the number of rotor magnetic poles is 3 In the iron core of a rotating electrical machine that is a pair 2, the distance from the tooth surface facing the magnet surface to the back yoke is divided into three by two symmetrical slits with respect to the center line. An angle obtained by dividing the circumference 360 ° by the number of magnetic poles of the iron core is defined as a unit angle θ of the magnetic pole, a quarter dividing line of θ is A, and a half dividing line B is B. The angle between the edge of the slit and the dividing line A is θa1, the angle between the slit opening and the dividing line A is θa2, and the angle between the slit opening and the dividing line B of the central magnetic path of the teeth is θb. / Θa2 and 2θa2 / θb are equal And the sum of the values of 2θb / θa2 and θa1 / θa2 or the sum of the values of 2θb / θa2 and 2θa2 / θb is close to 4 is disclosed. Has been.

  That is, in the above technique, the magnetic circuit is divided by the slit, and the second harmonic of the fundamental frequency of the cogging torque when the number of magnetic poles of the iron core is the minimum number of poles such as 3 and the number of magnet poles is 2. Has been disclosed to reduce the cogging torque and smooth it.

However, the above technique is limited in that the second harmonic of the fundamental frequency of the cogging torque is generated to reduce and smooth the cogging torque.
Japanese Patent Application No. 2010-135549

    The iron core of a rotating electrical machine according to the technique of Patent Document 1 can be considered to improve performance in the following points.

  In the iron core according to the technique of Patent Document 1, it is impossible to completely eliminate the cogging torque at the minimum number of poles such as three poles and two magnet poles. Absent.

  The present invention is a technique for solving the above-described problems. Even in the case of three poles and two poles where the number of stator magnetic poles and the number of rotor poles are minimum values, the cogging torque is completely eliminated and high efficiency is achieved. , To provide technology that enables small, high-output rotating electrical machines.

  In order to solve the above object, the present invention has the following technical means.

That is, the present invention will be described using the reference numerals in the accompanying drawings corresponding to the embodiments. The present invention has a stator magnetic pole number that is a multiple of 3 and a magnetic pole number that is a multiple of 2, between the magnetic poles of a rotor having a sinusoidal orientation. Permanent magnet rotor with no gap, centering on the distance from the tooth surface facing the magnet surface to the back yoke of the iron core of a rotating electrical machine with a ratio of the number of stator magnetic poles to the number of rotor magnetic poles of 3 to 2 On the other hand, the tooth is divided into three parts by two symmetrical slits, and the angle obtained by dividing the circumference 360 ° of the iron core by the number of magnetic poles of the iron core is defined as the unit angle θ of the magnetic pole, and a dividing line that is a quarter of the θ is A is defined as A, a half dividing line is B, an angle between the end of the slot opening of the tooth and the dividing line A is θa1, an angle between the end of the slit opening and the dividing line A is θa2, and the central magnetic field of the tooth The edge of the slit opening of the road and the corner of the dividing line B Assuming that the degree is θb, the condition that the values of θa1 / θa2 and 2θa2 / θb are equal, the sum of the values of 2θb / θa2 and θa1 / θa2, or the sum of the values of 2θb / θa2 and 2θa2 / θb is unlimited. to satisfy to become closer at the core of a rotary electric machine characterized by, the numerical value magnetic circuit width T _a of the magnetic circuit of the divided iron core is divided by a back yoke thickness T at P ² 2θa1 / 90 by slits An iron core of a rotating electric machine characterized by

  Based on the above configuration of the present invention, the permanent magnet rotor has a stator magnetic pole number that is a multiple of 3 and a magnetic pole number that is a multiple of 2, and the number of stator poles is 1.5 times the number of rotor magnetic poles. In addition, the technology that completely eliminates the cogging torque and enables smooth rotation characteristics is provided.

  That is, as a result of completely eliminating the cogging torque, a high-efficiency rotating electric machine having excellent rotation characteristics is made possible.

  In addition, even when the number of magnetic poles of the stator core is 3 poles and the number of rotor poles is 2 poles, the cogging torque is completely extinguished, enabling smooth rotation characteristics, high efficiency and ultra high speed. Enables a rotating electric rotating machine.

  Based on the above configuration, an embodiment will be described in detail with reference to the accompanying drawings.

FIG. 1 shows an example of an embodiment, that is, a permanent magnet rotor having a number of stator poles that is a multiple of 3 and a number of poles that is a multiple of 2, and having a sinusoidal orientation. The teeth of a rotating electrical machine core with a rotor magnetic pole ratio of 3 to 2 are divided into three parts by two symmetrical slits with respect to the center line from the tooth surface facing the magnet surface to the back yoke. An angle obtained by dividing the circumference 360 ° of the iron core by the number of magnetic poles of the iron core is defined as a unit angle θ of the magnetic pole, a quarter dividing line of θ is A, and a half dividing line is B. The angle between the end of the tooth slot opening and the dividing line A is θa1, the angle between the end of the slit opening and the dividing line A is θa2, and the angle between the slit opening end of the central magnetic path of the teeth and the dividing line B Is θb, and the values of θa1 / θa2 and 2θa2 / θb are In an iron core of a rotating electrical machine characterized by satisfying the following conditions and the sum of the values of 2θb / θa2 and θa1 / θa2 or the sum of the values of 2θb / θa2 and 2θa2 / θb is close to 4 in it, a core of a rotating electrical machine magnetic circuit width T _a of the magnetic circuit of the divided iron core by the slit is characterized by comprising a back yoke thickness T to a number divided by P ² 2θa1 / 90. (P is the number of rotor poles)

  That is, according to FIG. 1, a permanent magnet rotor having a stator magnetic pole number that is a multiple of 3 and a magnetic pole number that is a multiple of 2 is provided, and the iron core of a rotating electrical machine has a ratio of the stator magnetic pole number to the rotor magnetic pole number of 3 to 2. This is an example of a three-pole stator magnetic pole and a two-pole permanent magnet rotor. The slit 4 is symmetrical with respect to the center line with respect to the distance from the surface of the teeth 2 facing the magnet surface to the back yoke 3. It is the figure which divided the tooth | gear into two and formed the magnetic circuit.

Further, an angle obtained by dividing the circumference 360 ° of the iron core by the number of magnetic poles of the iron core is set as a unit angle θ of the magnetic pole, a quarter dividing line of θ is A, and a half dividing line is B. The angle between the end of the slot opening of the tooth and the dividing line A is θa _1, and the angle between the end of the slit opening and the dividing line A is θa ₂ , and the end of the slit opening of the central magnetic path of the tooth and the dividing line B Is the condition where the values of θa ₁ / θa ₂ and 2θa ₂ / θb are equal and the sum of the values of 2θb / θa ₂ and θa ₁ / θa ₂ or 2θb / θa ₂ and 2θa ₂ / θb in the iron core of an electric rotating machine, the magnetic circuit width T _a of the magnetic circuit of the divided core by slits the back yoke thickness T P the sum of the values, characterized in that it satisfies that close to 4 as possible ² With the iron core of a rotating electrical machine characterized by the value divided by 2θa1 / 90 is there. (P is the number of rotor poles)

  Conventionally, the fundamental harmonic of the cogging torque is the least common multiple of the number of stator poles and permanent magnet rotor poles, and it is 6 harmonics when the number of stator poles is 3 and the permanent magnet rotor is 2 poles.

  Next, according to the invention of the above-mentioned Patent Document 1, when the magnetic circuit and the magnetic field lines at the rotor rotation position every 30 ° in the iron core are verified, it can be seen that there are two types of magnetic circuits shown in FIGS. .

  In other words, it is considered that the second harmonic is generated and the cogging torque is minimized when the attractive forces of the magnets in these two types of magnetic circuits are equal and balanced.

That is, in the case of FIGS. 3 and 4, when the vector field of a two-pole magnet rotor having a sinusoidal orientation is analyzed, the angle obtained by dividing the circumference 360 ° of the iron core by the number of magnetic poles of the iron core. Is a unit angle θ of θ, A is a dividing line that is a quarter of θ, B is a dividing line that is a half, and θa ₁ is the angle between the end of the slot opening of the tooth and the dividing line A, and the slit Assuming that the angle between the edge of the opening and the dividing line A is θa ₂ and the angle between the edge of the slit opening of the central magnetic path of the teeth and the dividing line B is θb, the values of θa ₁ / θa ₂ and 2θa ₂ / θb are equal. Or when the conditions are almost equal and the sum of the values of 2θb / θa ₂ and θa ₁ / θa ₂ or the sum of the values of 2θb / θa ₂ and 2θa ₂ / θb is close to 4 In the two types of magnetic circuits of FIG. 3 and FIG. Cogging torque becomes the equilibrium state will be the minimum value.

  That is, the sum of the attractive forces due to the magnetic lines L (dashed line), magnetic line M (broken line) and magnetic line S (solid line) shown in FIG. The sum of the attractive forces of the magnetic field line S (solid line) is equal, and at this time, the second harmonic is generated and the cogging torque of the rotor becomes the minimum value.

  Next, in this patent, we will elaborate on the technology to eliminate the cogging torque completely by eliminating the difference in cogging torque that is the cause of this second harmonic.

In this patent, it is the core of a rotating electric machine, characterized in that for the numerical obtained by dividing the magnetic circuit width T _A of the magnetic circuit of the divided core by slitting the back yoke thickness T at P ² 2θa1 / 90. (P is the number of rotor poles)

That, by the magnetic circuit width T _A according to the above formula, 0 ° and 30 ° of one another to reduce the value of the cogging torque, which occurs a second harmonic position, all of the rotor rotational position In this case, it is possible to make the cogging torque disappear by matching the values of the cogging torque.

That, by the magnetic circuit width T _A according to the official this patent as in FIG. 5, by making a deliberate leakage flux to the magnetic flux passing through the magnetic circuit T _A, all numbers cogging torque is controlled At the rotor rotation position, the cogging torque values coincide and the cogging torque disappears completely. The numbers in the figure show the magnetic flux corresponding to each magnetic circuit divided by the slits, and the magnetic sine wave. The area value of orientation is expressed as the strength of magnetic flux.

  Table 1 below FIG. 5 is a numerical value obtained by calculating the cogging torque from the area value corresponding to each magnetic circuit and the length ratio of the magnetic circuit. Since the leakage flux does not generate the cogging torque, the total value of the cogging torque is calculated. Will be deducted.

That is, if θa1 as 28.1 ° when the number of stator poles 3 and the number of rotor poles as in Figure 5 is 2, when designing the stator core than the official, T _A is approximately the T 1/2. 5

  It can be seen that the maximum value of the magnetic circuit L magnetic flux passing through the back yoke T is a numerical value 539.8 (area value) in the state of 0 ° in FIG.

Thus the maximum value of the magnetic flux passing through the _{T A} is the numerical value 216 of 1 / 2.5.

That is, 0 value of the magnetic flux corresponding to T _A is at the position of ° is the leakage flux 78.8 on one side because it is 294.8 (area value).

  Therefore, the effective cogging torque value is 1760.9, which is obtained by subtracting the leakage flux from the total cogging torque value 1918.5 in the table 1 below.

  Similarly, calculating 15 ° and 30 ° gives the results shown in Table 2 in Fig. 6 and Table 3 in Fig. 7. (Figures 6 and 7 show the rotor fixed and the stator iron core rotated.)

However, leakage flux 6 will lower leakage magnetic flux to the upper leakage flux 78.4 is constrained flanked on the effective magnetic flux in a narrow magnetic path of the lower portion of T _A to 49.1, i.e. 29 .3 works as cogging torque.

  As detailed above, the effective cogging torque value is 1761 in consideration of the calculation error at all rotational positions, and the cogging torque disappears completely and smooth rotation is realized.

  The above description is an example of the embodiment, and is a permanent magnet rotor having a stator magnetic pole number that is a multiple of 3 and a magnetic pole number that is a multiple of 2, and the ratio of the stator magnetic pole number to the rotor magnetic pole number is 3 to 2. Any number of poles may be used as long as it is an iron core, and the core material may be any material such as a laminate of electromagnetic steel sheets or a dust core.

  As described above, in a rotating electrical machine that requires high efficiency, the cogging torque is completely achieved even in a rotating electrical machine having a minimum number of magnetic poles of 3 stator rotors and 2 rotor poles. This is the only technology that can be extinguished, and it is an iron core of a rotating electrical machine that can achieve ideal characteristics that can realize stable rotational torque and improve characteristics.

It is a top view of the Example of the 3 pole stator iron core of this invention. It is a top view of the Example of the outer rotor of the 6 pole stator iron core of this invention. It is explanatory drawing of the attractive force by a magnetic force line when the rotation angle of patent document 1 is 0 degree. It is explanatory drawing of the attractive force by a magnetic force line when the rotation angle of patent document 1 shall be 30 degrees. It is the figure which showed 0 degree of rotation angles of the 3 pole stator iron core of this invention. It is the figure which showed the rotation angle of 15 degrees of the 3 pole stator iron core of this invention. It is the figure which showed the rotation angle of the 3 pole stator iron core of this invention 30 degrees.

1 Iron core 2 Teeth 3 Back yoke 4 Slit 5 Slot 6 Magnet rotor L Magnetic field line (dashed line)
M Magnetic field lines (broken line)
S Magnetic field line (solid line)

Claims (1)

A permanent magnet rotor having a stator magnetic pole number that is a multiple of 3 and a magnetic pole number that is a multiple of 2 with no gap between the magnetic poles of the rotor having a sinusoidal orientation, and the ratio of the stator magnetic pole number to the rotor magnetic pole number is 3 to 2 The tooth of the rotating electrical machine core is divided into three by two symmetrical slits about the distance from the tooth surface facing the magnet surface to the back yoke, and the circumference of the iron core is 360 °. Is divided by the number of magnetic poles of the iron core as the unit angle θ of the magnetic pole, and a dividing line that is a quarter of θ is A, and a dividing line that is a half is B, and the end of the slot opening of the teeth The angle of the dividing line A is θa1, the angle between the end of the slit opening and the dividing line A is θa2, and the angle of the slit opening end of the central magnetic path of the teeth and the dividing line B is θb, and θa1 / θa2 and 2θa2 The condition that the values of / θb are equal; In the iron core of a rotating electrical machine characterized by satisfying that the sum of the values of θb / θa2 and θa1 / θa2 or the sum of the values of 2θb / θa2 and 2θa2 / θb is nearly 4 core of a rotating electrical machine magnetic circuit width T _a of the magnetic circuit of the divided iron core is characterized by comprising a back yoke thickness T to a number divided by P ² 2θa1 / 90.

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