JP2010088271A - Permanent magnet type synchronous motor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable employing optional combinations while reducing a circular current in the relation between the number n of magnetic poles and the number m of slots giving an expectation on a high-torque motor. <P>SOLUTION: The permanent magnet type synchronous motor has a structure where a current circuit through which phase current of same phase (U-phase) flows includes a parallel circuit in which four serial circuits each formed of two stator coils 5-1A and 5-14A, 5-2A and 5-13A, 5-1B and 5-14B, and 5-2B and 5-13B, and one stator coil circuit formed of one stator coil 5-0 are connected in parallel. In the synchronous motor, of the nine stator coils, the stator coils in which an inter-stator coil voltage generated by the phase difference between a magnetic angle and an electric angle is in a positive-negative relation are arranged in each of the serial circuits so that the induction voltages of the four serial circuits may be almost the same, and slots each in which the two stator coils are arranged for one slot is provided. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a permanent magnet type synchronous motor, and more particularly to a permanent magnet type synchronous motor that reduces circulating current and increases the degree of freedom in selecting the number of magnetic poles and the number of slots.

  For the purpose of improving torque while preventing an increase in torque ripple in a permanent magnet synchronous motor, conventionally, for example, in Patent Document 1, the number of magnetic poles made of permanent magnets is n (n = 2N, where N is an integer). It is proposed that the motor satisfy the condition of 2m / 3 <n <4m / 3, where m is the number of slots formed of winding coils (m = 3M, where M is an integer). .

  According to such an electric motor, the winding coefficient formed by the product of the short-pitch coefficient and the distribution coefficient can be increased as compared with, for example, a normal motor in which the number of magnetic poles n: the number of slots m is 2: 3. Can be obtained.

Further, in order to operate such an electric motor with a small number of current phases, in Patent Document 1, a plurality of coils in a plurality of slots having the same phase are selectively connected in series and in parallel to each other. It has been proposed to prevent circulating currents in parallel circuits.
Japanese Patent Laid-Open No. 2002-272074

  However, in the above prior art connection method, slots are selectively connected in series and parallel to prevent circulating current. However, in order to prevent circulating current, as a precondition, a common multiple between the number of magnetic poles n and the number of slots m is used. Had to have. In other words, when trying to select the relationship between the number of magnetic poles n and the number of slots m to increase the torque or reduce the torque ripple, the deterioration of the operating efficiency of the motor due to the circulating current cannot be avoided.

  Therefore, an object of the present invention is to provide a permanent magnet type synchronous motor that reduces the deterioration in efficiency due to circulating current and increases the degree of freedom in selecting the number of magnetic poles n and the number of slots m.

  The permanent magnet synchronous motor of the present invention that achieves the above object is a parallel circuit in which a plurality of stator coil circuits including a plurality of series circuits formed of a plurality of stator coils are connected in parallel to a current circuit through which phase currents of the same phase flow. Among the plurality of stator coils, the stator coils having a positive / negative relationship between the stator coil voltages generated by the phase difference between the magnetic angle and the electrical angle are arranged in each series circuit, and the plurality of series circuits The induced voltages are made substantially the same, and a plurality of slots in which the stator coils are arranged in one slot are provided.

  According to such a permanent magnet type synchronous motor of the present invention, a plurality of series circuits are provided by arranging the stator coils having a positive / negative relationship between the stator coil voltages generated by the phase difference between the magnetic angle and the electrical angle in each series circuit. When there is an odd number of coils in the same phase without increasing the induced voltage, since the induced voltage of the stator is made substantially the same, and a plurality of stator coils are arranged for one slot. Thus, the circulating current can be reduced, so that the degree of freedom in selecting the number of magnetic poles n and the number of slots m can be increased even in the case of a high torque type electric motor.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view showing a radial gap type motor having 15 slots and 14 magnetic poles constituting the first and second embodiments of the permanent magnet synchronous motor of the present invention. FIG. It is explanatory drawing which shows the characteristic table of the motor of an example.

  The motor shown in FIG. 1 is housed in a housing (not shown) and is rotatably supported by the housing, and the permanent magnet rotor 1 is housed in the housing and fixed to the housing. The rotor 1 has a stator 2 that surrounds from the outside, and the rotor 1 has 14 permanent magnets 3 at substantially equal intervals in the circumferential direction. The stator 2 is surrounded by an annular portion 4a and the annular portion 4a. An iron core 4 having 15 teeth 4b projecting radially inward at substantially equal intervals in the direction, a concentrated winding type stator coil 5 wound around each tooth 4b, and between adjacent teeth 3b Thus, the motor has 15 slots and 14 magnetic poles. A predetermined air gap 7 is formed in the radial direction between the rotor 1 and the tip of the tooth 4b of the stator 2.

  When this combination of the number of magnetic poles and the number of slots (slot combination) is adopted, a winding coefficient of 95.14 is obtained, resulting in a high torque motor, and 18-slot, 16-pole virtual 6-phase drive described in the prior art In comparison, a torque improvement of 1% or more can be expected. The motor in the present embodiment is a sub-distribution coefficient type concentrated winding motor because the distribution coefficient Kd is 95.67% which is less than 100% (= 1).

上記トルク式に基づき、電流の要件（供給電力の問題：Ｅ、Ｉ、k_R、ΦcosΦ）や構造上の制限（ｍ、ｗ、ｐ）を除くと、変更可能な値はk_w：巻線係数となる（但し、巻線係数もｐに依存する）。
このとき、巻線係数は下記の式で表される。

つまり、k_p：短節係数とk_d: 分布係数とは、トルクに直接関係する係数となる。分布係数は後述のように１が最大であり、分布係数が１未満の集中巻モータは、劣分布係数型集中巻モータとなる。 By the way, the torque T of the AC synchronous machine is obtained by the following torque equation.

Based on the above torque equation, excluding current requirements (supply problems: E, I, k _R, Φ cos Φ) and structural limitations (m, w, p), the changeable values are k _w : winding Coefficient (however, the winding coefficient also depends on p).
At this time, the winding coefficient is expressed by the following equation.

That is, k _p : short-pitch coefficient and k _d : distribution coefficient are coefficients directly related to torque. As will be described later, the distribution coefficient has a maximum value of 1 and a concentrated winding motor having a distribution coefficient of less than 1 is an inferior distribution coefficient type concentrated winding motor.

Here, the short-pitch coefficient k _p represents the difference between the coil pitch and the tooth pitch, with 1 being the maximum. However, a motor with a short bar coefficient of 1 cannot be started because all the magnets and the stator face each other. Therefore, the short-pitch coefficient is generally less than 1. Also, the distribution coefficient k _d, represents the degree of winding concentration of the coil, 1 is maximized. Most general motors use this method. Since the distribution coefficient depends on the number of driving phases, the distribution coefficient can always be 1 as long as the number of phases can be made freely, but there are limitations due to the total number of switches and difficulty in control.

To sum up the above viewpoints, when designing a motor with three-phase drive with good current efficiency, a distribution coefficient of 1 and a short node coefficient, the magnetic pole (number of magnets): slot (number of windings) should be 2: 3. This relationship can be easily met. Therefore, most motors in the form of 6 magnets with 3 magnets (3-phase 2-parallel drive) and 9 magnets with 6 magnets (3-phase 3-parallel drive) Designed.
If the winding coefficient is considered to be the product of the short-pitch coefficient and the distribution coefficient, and the above-mentioned general 2: 3 is observed, the limit of the winding coefficient is 0.866 (short-pitch coefficient: 0.866, distribution) Factor: 1). On the other hand, it is difficult to maintain the distribution coefficient at 1 if an attempt is made to increase the short coefficient as much as possible. Therefore, it is conceivable to make a motor capable of producing a high torque by increasing the short-pitch coefficient and making the distribution coefficient close to 1 without complicating the inverter.

  The permanent magnet type synchronous motor of the present invention is based on the above-described concept. For example, the motors of the first and second embodiments of the present invention shown in FIG. Since the drive is performed with the number 15, the number of magnetic poles 14, and the number of drive phases 3 (virtual 6 phases including reverse winding), the winding coefficient is 0.951 (short-path coefficient: 99.45%) as shown in the characteristic table of FIG. , Distribution coefficient: 95.67%). That is, even if the distribution coefficient is less than 1 (100%), a motor capable of producing a high torque can be produced by increasing the short-pitch coefficient.

Here, even if it is possible to design a motor capable of producing a high torque even if the distribution coefficient is less than 1 (100%), the distribution coefficient is less than 1 (100%). Have the problem of worsening the operating efficiency.
In the characteristic table shown in FIG. 2, the slot number is a mark for slot 6, the slot angle is a relative angle when the position of a specific slot 6 is 0 degree, and the magnetic angle is 14 poles. The electrical timing given to the stator coil 5 indicates the energization timing to the stator coil 5 that can be achieved by three-phase driving. In general three-phase driving, power can be supplied only at the timing of 0 degree, 120 degrees, and 240 degrees. In the first and second embodiments, as shown in the characteristic table, the stator coil 5 has a reverse winding coil. Therefore, energization equivalent to energization at 60 degrees, 180 degrees, and 300 degrees is possible. That is, since the opposite of 0 degrees is 180 degrees, if a normal winding coil at a position of 0 degrees and a reverse winding coil at a position of 180 degrees are connected in parallel, energization of 0 degrees and 180 can be performed simultaneously with a single phase current. . Similarly, energization of 120 degrees of inversion 300 degrees and 240 degrees of inversion 420 degrees = 60 degrees can be performed.

  However, it can be seen from the above characteristic table that a phase shift occurs when energization satisfying the above magnetic angle is performed with a three-phase drive inverter (virtual six phases). For example, when an ideal energization is performed with one of the U-phase reverse wound coils, a slight phase shift occurs in the remaining four coils arranged in the same phase. In order to drive without phase shift, an inverter (15-phase or 30-phase inverter) that can control the electrical angle in 12 degree increments is required, which is not realistic, and phase shift must be allowed. Absent.

  However, in the conventional parallel stator coil connection method, as shown in FIGS. 9 and 10, as a result of a slight phase shift, a difference occurs in the induced voltage between the stator coils and a circulating current is generated. For example, take out U-phase stator coils 5-13, 5-14, 5-0, 5-1, 5-2 (corresponding to slot numbers 13, 14, 0, 1 and 2 in the characteristic table shown in FIG. 2). When connected in parallel as shown in FIG. 9A, the current vector can be expressed as shown in FIG. 9B in consideration of the above phase difference. In addition, the code | symbol attached | subjected to the vector shows a corresponding stator coil. The direction of the line perpendicular to the perpendicular is the voltage. Assuming that energization is stopped and only the rotor is rotated, when the induced voltage of the vector 5-0 is generated when the central stator coil 5-0 faces the magnet, another parallel stator coil 5-13 , 5-14, 5-1, 5-2 cannot be directly opposed to the magnet due to the slot-magnetic pole relationship, and there are those that are delayed and those that advance.

  FIG. 10A representatively shows the three vectors in the center of FIG. 9B, and the stator coil 5-14 corresponding to these vectors 5-14, 5-0, and 5-1 is shown. , 5-0, 5-1 are connected in parallel as shown in FIG. Due to the difference in timing between the vectors 5-14, 5-0 and 5-1, there is a difference in the induced voltages of the stator coils 5-14 and 5-1, and as a result, current flows in the direction with the potential difference. As a result, the circulating current Ic is generated and the operating efficiency of the motor is deteriorated.

  FIG. 3A is a circuit diagram representatively showing the U phase of the three phases of the coil connection method in the motor of the first embodiment of the present invention for preventing the circulating current as described above. (B) is explanatory drawing which shows the state of the electric current vector of each stator coil in the coil connection method of the 1st Example. In addition, the code | symbol attached | subjected to the vector shows a corresponding stator coil. That is, here, as in the modification of this embodiment shown in FIG. 4B, one stator coil 5 is wound around the teeth of slot number 0 of the U phase and slot numbers 13, 14, 1, and 2 are wound. Two stator coils 5 are wound around each tooth, and stator coils 5-13A, 5-13B, 5-14A, 5-14B, 5-0, 5-1A, 5-1B, 5-2A, 5-2B are wound. Is provided.

  In the first embodiment, as shown in FIG. 3A, the stator coil 5-1A and the stator coil 5-14A, in which the voltage between the stator coils is positive and negative, are connected in series to form a series as a stator coil circuit. Similarly, the stator coil 5-2A and the stator coil 5-13A, the stator coil 5-1B and the stator coil 5-14B, and the stator coil 5-2B and the stator coil 5-14B are connected in series, respectively. The four series circuits and the stator coil circuit having only the stator coil 5-0 are connected in parallel to each other to form a U-phase current circuit. The V phase and the W phase in the characteristic table of FIG. 2 are configured similarly to the U phase.

  According to the configuration of the first embodiment, as shown in FIG. 3 (b), the induced voltages of the current vectors 5-1B and 5-14B having the same angle and positive and negative phases with respect to the central current vector 5-0. Are the sum of the induced voltages of the current vectors 5-14A and 5-1A, the sum of the induced voltages of the current vectors 5-2B and 5-13B, and the sum of the induced voltages of the current vectors 5-13A and 5-2A. Since the induced voltage in the series circuit is added in parallel to the induced voltage of the current vector 5-0 of the central stator coil circuit, the circulating current is reduced by minimizing the difference in the induced voltage of each stator coil circuit. Since the motor can generate a high torque, the operating efficiency can be reduced slightly by the induced voltage. In addition, each series circuit does not generate an induced voltage higher than that of the central stator coil 5-0, which is advantageous in terms of the withstand voltage of the inverter switch circuit. Furthermore, since there is only one stator coil 5-0 at the center, the configuration of the stator 2 can be simplified.

FIG. 4A is a circuit diagram representatively showing the U phase of the three phases of a modification of the first embodiment, and FIG. 4B is an arrangement and connection state of the stator coil of the modification. In this modification, stator coils wound around the same tooth are connected in parallel. According to such wiring, for example, as in the embodiment of FIG. 3A, wiring connecting the stator coil 5-1A and the stator coil 5-14A, and between the stator coil 5-1B and the stator coil 5-14B. However, according to the embodiment of FIG. 4B, they can be used as a common wiring.
Even in such a wiring, the effect of minimizing the difference in induced voltage is the same as that of the first embodiment, and in this way, the wiring between the teeth can be reduced, and the actual wiring is easy. Can be.

  FIG. 5A is a circuit diagram representatively showing the U phase of the three phases of the coil connection method in the motor according to the second embodiment of the present invention for preventing the circulating current as described above. (B) is explanatory drawing which shows the state of the electric current vector of each stator coil in the coil connection method of the 2nd Example. In addition, the code | symbol attached | subjected to the vector shows a corresponding stator coil. That is, here, as in the modification of this embodiment shown in FIG. 6B, four stator coils 5 of teeth 4b of U-phase slot number 0 are wound and slot numbers 13, 14, 1, 2 are wound. The stator coils 5 of each tooth 4b are wound two by two, and the stator coils 5-13A, 5-13B, 5-14A, 5-14B, 5-0A, 5-0B, 5-0C, 5-0D, 5 -1A, 5-1B, 5-2A, and 5-2B are provided.

  In the second embodiment, as shown in FIG. 5 (a), the stator coil 5-1A and the stator coil 5-14A in which the voltage between the stator coils has a positive / negative relationship are connected in series and the stator coil 5-0A is connected thereto. Are connected in series to form a series circuit as a stator coil circuit. Similarly, the stator coil 5-1B, the stator coil 5-14B, the stator coil 5-0B, the stator coil 5-2A, the stator coil 5-13A, and the stator coil 5 −0C, stator coil 5-2B and stator coil 5-13B and stator coil 5-0D are connected in series to form a series circuit as a stator coil circuit, and the phase and amplitude of the induced voltage of these four series circuits are The U-phase current circuit is configured by connecting these series circuits in parallel with each other. To have.

  According to the configuration of the second embodiment, as shown in FIG. 5B, the induced voltages of the current vectors 5-14A and 5-1A having the same angle and positive and negative phases with respect to the central current vector 5-0A. And the induced voltage of the current vector 5-0A in the center, the induced voltage of the current vectors 5-1B and 5-14B having the same angle at the same angle as the central current vector 5-0B, and the current in the center The sum of the induced voltage of the vector 5-0B and the induced voltage of the current vectors 5-13A and 5-2A having the same angle and different phase with respect to the central current vector 5-0C and the central current vector 5-0C. The induced voltage of the current vectors 5-2B and 5-13B, which are different in phase from the sum of the induced voltage and the central current vector 5-0D at the same angle in the positive and negative directions, and the central current vector 5-0 Since the sum of the induced voltage and the induced voltage is added in parallel as an induced voltage in each series circuit, the difference in induced voltage in each series circuit can be suppressed to almost zero, and the circulating current can be eliminated almost or not at all. With a high-torque motor, there can be little or no reduction in operating efficiency due to induced voltage. Further, since each series circuit generates substantially the same induced voltage, it is advantageous in terms of the withstand voltage of the inverter switch circuit.

  FIG. 6A is a circuit diagram representatively showing the U phase of the three phases of a modification of the second embodiment, and FIG. 6B is an arrangement and connection state of the stator coil of the modification. In this modification, stator coils wound around the same tooth are connected in parallel. Even with such a wiring, the effect of minimizing the difference in the induced voltage is the same as that of the second embodiment, and in this way, the actual wiring can be facilitated.

  FIG. 7 shows a stator coil connection of the first embodiment shown in FIGS. 3 and 4 and its modification shown in FIGS. 3 and 4, and the second embodiment and its modification shown in FIGS. FIG. 10 is an explanatory diagram showing the phase and amplitude of the induced voltage in the stator coil connection and the inductance in comparison with those in the normal parallel stator coil connection shown in FIG. 9, and thus in comparison with the normal parallel type. Then, according to the first embodiment and its modification, it is possible to provide a motor with a simple configuration in which the central stator coil is not a split type, the amplitude of the induced voltage is slightly different but the phase and inductance are uniform, Further, according to the second embodiment and its modification, the configuration is complicated because the central stator coil is a split type, but the amplitude and phase of the induced voltage are uniform and the inductance is slightly different. It is possible.

  FIG. 8 shows a third embodiment of the permanent magnet type synchronous motor according to the present invention. The basic configuration is the same as in FIG. 1, and the number of slots is 27, the number of magnetic poles is 22, and the number of drive phases is 9 (virtual 18 phases). It is explanatory drawing which shows the characteristic table | surface of the motor driven with a drive inverter, and in order to drive this motor, although the inverter which can normally control electricity supply every 16 degrees is used, since it is not a divisible value in the first place, the circulating current However, using the method of the present invention, for example, among the stator coils 5 wound in a concentrated winding form on the three adjacent teeth 4b of each of the nine phases, the voltage between the stator coils has a positive / negative relationship. Two stator coils 5 of the two teeth 4b on both sides are respectively provided in two, and the two stator coils 5 are connected in series between the two teeth 4b on both sides to form two series circuits. By configuring these two series circuits in parallel with each other and with a stator coil circuit consisting of one stator coil 5 in the central tooth 4b, the circulating current is reduced without increasing the induced voltage as in the previous embodiment. can do.

  5 and 6, the central stator coil 5-0 is divided into four parts and distributed to four series circuits. Instead, the central stator coil 5 is used instead. As shown by phantom lines in FIG. 5, −0 is divided into five, among which four stator coils 5-0A to D are distributed to four series circuits, and the remaining one is the stator coil 5 A stator coil circuit is configured only by −0E, the phases and amplitudes of the induced voltages of those stator coil circuits are aligned, and the stator coil circuits are arranged in parallel as in the first embodiment and its modification shown in FIGS. A one-phase parallel circuit may be configured by connecting to the circuit.

  Although the present invention has been described based on the illustrated examples, the present invention is not limited to the above-described examples, and can be appropriately changed within the scope of the claims. Although this motor is of a radial gap type having an air gap in the radial direction, the present invention can also be applied to an axial gap type motor having an air gap in the axial direction, and has the same effect as the above example. Can play.

  Thus, according to the permanent magnet type synchronous motor of the present invention, a plurality of series circuits are provided by arranging the stator coils in which the stator coil voltage generated by the phase difference between the magnetic angle and the electrical angle has a positive / negative relationship in each series circuit. When there is an odd number of coils in the same phase without increasing the induced voltage, since the induced voltage of the stator is made substantially the same, and a plurality of stator coils are arranged for one slot. The circulating current can be reduced even in the case where the number of magnetic poles n and the number of slots m are 2m / 3 <n <4m / 3. Arbitrary combinations can be adopted.

  In the permanent magnet type synchronous motor of the present invention, only one of the plurality of stator coils having no phase difference between the magnetic angle and the electrical angle constitutes one of the plurality of stator coil circuits. In this case, the stator can have a simple configuration.

  Further, in the permanent magnet type synchronous motor of the present invention, all of the plurality of stator coil circuits are the series circuit, and among the plurality of stator coils, a stator coil having no phase difference between a magnetic angle and an electrical angle is provided. The plurality of stator coils are distributed in series and connected in series to a stator coil having a positive / negative relationship between the stator coil voltages generated by the phase difference between the magnetic angle and the electrical angle of each series circuit. The induced voltages of the circuits may be the same, and in this way, little or no circulating current can be eliminated.

  Furthermore, in the permanent magnet type synchronous motor according to the present invention, a part of the stator coils having no phase difference between the magnetic angle and the electrical angle among the plurality of stator coils, wherein one of the plurality of stator coil circuits is arranged. Between the stator coils generated by the phase difference between the magnetic angle and the electrical angle of each of the series circuits by distributing the remainder of the stator coil having no phase difference between the magnetic angle and the electrical angle to the plurality of series circuits. The induced voltages of the plurality of stator coil circuits may be the same by connecting them in series to a stator coil having a positive / negative voltage relationship, and in this case, little or no circulating current is eliminated. Can do.

  Furthermore, in the permanent magnet type synchronous motor according to the present invention, the circuits between the plurality of stator coils forming the series circuits may be connected to each other by the plurality of series circuits. Can be.

  Furthermore, in the permanent magnet type synchronous motor of the present invention, when the number of magnetic poles made of the permanent magnets of the rotor is n and the number of slots in which the stator coils are arranged is m, the range is 2 m / 3 <n <4 m / 3. In addition, the number of slots m may be an odd number, and in this way, a high torque electric motor can be obtained.

  In the permanent magnet type synchronous motor of the present invention, the number of slots m = 15 and the number of magnetic poles n = 14 or the number of slots m = 27 and the number of magnetic poles n = 22 may be set. Since the relationship of 2m / 3 <n <4m / 3 is satisfied, a high torque electric motor can be obtained.

It is sectional drawing which shows the radial gap type motor of the slot number 15 and the magnetic pole number 14 which comprises the 1st and 2nd Example of the permanent-magnet-type synchronous motor of this invention. It is explanatory drawing which shows the characteristic table | surface of the motor of the said Example. (A) is a circuit diagram representatively showing the U phase of the three phases of the coil connection method in the motor of the first embodiment, and (b) is a diagram of each stator coil in the coil connection method of the first embodiment. It is explanatory drawing which shows the state of an electric current vector. (A) is a circuit diagram representatively showing the U phase of the three phases of a modification of the first embodiment, and (b) is an explanatory diagram showing the arrangement and connection state of the stator coils of the modification. is there. (A) is a circuit diagram representatively showing the U phase of the three phases of the coil connection method in the motor of the second embodiment, and (b) is a diagram of each stator coil in the coil connection method of the second embodiment. It is explanatory drawing which shows the state of an electric current vector. (A) is a circuit diagram representatively showing the U phase of the three phases of a modification of the second embodiment, and (b) is an explanatory diagram showing the arrangement and connection state of the stator coils of the modification. is there. In the configuration of the motor shown in FIGS. 1 and 2, the stator coil connection of the first embodiment and its modification shown in FIGS. 3 and 4, the second embodiment and the stator coil connection of its modification shown in FIGS. FIG. 10 is an explanatory diagram showing the phase and amplitude of the induced voltage and the inductance in comparison with those in the normal parallel stator coil connection shown in FIG. 9. As a third embodiment of the permanent magnet type synchronous motor of the present invention, the basic configuration is the same as FIG. 1 and is a 9-phase drive inverter having 27 slots, 22 magnetic poles, and 9 driving phases (virtual 18 phases). It is explanatory drawing which shows the characteristic table | surface of the motor to drive. (A) is a circuit diagram which shows the connection method of the conventional parallel type stator coil, (b) is explanatory drawing which shows the state of the current vector of each stator coil in the parallel type circuit. (A) is representative of the three vectors in the center of FIG. 9 (b), and FIG. 9 (b) is an explanatory diagram showing the occurrence of circulating current in the vector state shown in FIG. 9 (a). is there.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Stator 3 Permanent magnet 4 Iron core 4a Annular part 4b Teeth 5,5-0,5-0A-E, 5-1,5-1A, 5-1B, 5-2,5-2A, 5-2B, 5-13, 5-13A, 5-13B, 5-14, 5-14A, 5-14B Stator coil or current vector corresponding thereto 6 slots 7 air gap

Claims (7)

The current circuit through which the phase current of the same phase flows is constituted by a parallel circuit in which a plurality of stator coil circuits including a plurality of series circuits formed of a plurality of stator coils are connected in parallel,
Among the plurality of stator coils, stator coils having a positive / negative relationship between the stator coil voltages generated by the phase difference between the magnetic angle and the electrical angle are arranged in each series circuit, and the induced voltage of the plurality of series circuits is To be nearly identical,
A permanent magnet type synchronous motor provided with a slot in which a plurality of the stator coils are arranged with respect to one slot.   2. The permanent magnet synchronization according to claim 1, wherein only one of the plurality of stator coils has no phase difference between a magnetic angle and an electrical angle, and constitutes one of the plurality of stator coil circuits. Electric motor. All of the plurality of stator coil circuits as the series circuit,
A stator coil produced by distributing a stator coil having no phase difference between a magnetic angle and an electrical angle among the plurality of stator coils to the plurality of series circuits, and resulting from a phase difference between the magnetic angle and the electrical angle of each series circuit. The permanent magnet synchronous motor according to claim 1, wherein the induced voltages of the plurality of stator coil circuits are made the same by being connected in series to a stator coil having a positive and negative voltage relationship.   Among the plurality of stator coils, a part of the stator coil having no phase difference between the magnetic angle and the electrical angle constitutes one of the plurality of stator coil circuits, and the magnetic angle and the electrical angle The remainder of the stator coil having no phase difference is distributed to the plurality of series circuits, and the stator coil voltage generated by the phase difference between the magnetic angle and the electrical angle of each series circuit is in series with the stator coil having a positive or negative relationship. The permanent magnet synchronous motor according to claim 1, wherein the induced voltages of the plurality of stator coil circuits become the same by being connected.   The wiring which connects the several stator coils which form the said series circuit, and the wiring which connects the several stator coils which form another series circuit are connected by the common wiring, either A permanent magnet type synchronous motor according to claim 1. The permanent magnet synchronous motor is
When the number of magnetic poles composed of permanent magnets of the rotor is n and the number of slots in which the stator coils are arranged is m,
In the range of 2 m / 3 <n <4 m / 3,
The permanent magnet synchronous motor according to any one of claims 1 to 5, wherein the number of slots m is an odd number. The slot number m = 15 and the magnetic pole number n = 14, or the slot number m = 27 and the magnetic pole number n = 22.
The permanent magnet synchronous motor according to claim 6, wherein

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