TW201330456A - Variable frequency speed regulation motor device - Google Patents

Abstract

The present invention provides a small-sized and long-service variable frequency speed regulation motor device. The variable frequency speed regulation motor device comprises: a motor having a stator configured for arranging many groups of three-phase stator windings wound in a plurality of grooves in a peripheral direction of the motor and a rotor with a permanent magnet at a periphery; and a plurality of three-phase convertors for driving the three-phase stator windings, wherein the each phase winding of the three-phase stator windings consists of a plurality of filaments of wound wires, the stator windings of the each group received in the plurality of grooves are directly connected to the corresponding three-phase convertor, overlapping parts are arranged between windings of the stator windings, insulators with high insulating strength are arranged on the overlapping parts between the stator windings received between the grooves, insulators with an insulating strength lower than the insulating strength of the above insulators are arranged on the overlapping parts between the stator windings received between the adjacent grooves.

Description

Variable frequency motor device

The present invention relates to a variable frequency motor device, and more particularly to a small and long life variable frequency motor device.

In addition to the low price, small size and light weight, and low torque chopping, the variable frequency motor device is also required to have shock resistance and long life even in an environment with high vibration.

In the case of an electric motor that can achieve some of these requirements, the following disclosure techniques are available.

In the first disclosure, a two-phase three-phase stator winding is disclosed in one motor in the patent document 1 (JP-A-2000-175420), and the two sets of three-phase stator windings are respectively two sets of inverters. A variable frequency motor device that is driven by the device.

In the second disclosure, a permanent magnet motor structure having high torque and capable of reducing torque chopping is disclosed in Patent Document 2 (Japanese Patent Publication No. 2765764). Here, a structure of a fractional-slot motor in which the number of slots per phase per phase of the motor is 8 poles in the case of a permanent magnet rotor and 36 slots in the case of a fixed sub-slot is disclosed (the integer cannot be divided by an integer) . In particular, a motor different from the integer slot generally used is disclosed, and the windings constituting the one pole are configured to be different for each pole.

In the third disclosure, a productive lifting or lifting winding in a slot is disclosed in Patent Document 3 (JP-A-2009-195006). An example of the structure of a motor such as the occupation ratio. Here, a configuration in which a flat-angle winding is used, in particular, a connection between the same poles is continuously wound, and the connection work between the coils is omitted.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2000-175420

[Patent Document 2] Japanese Patent No. 2765764

[Patent Document 3] Japanese Patent Laid-Open Publication No. 2009-195006

According to the above Patent Document 1, it is possible to use a multi-phase stator winding that does not drive a motor by a large inverter, and to use a plurality of smaller inverters that are divided, thereby making it more versatile. High frequency converter and low cost.

In the configuration of the fractional-slot motor of Patent Document 2, it is revealed that the plurality of stator windings connected as the in-phase have different phases with respect to the permanent magnets, thereby selecting the average of the number of slots per phase per integer. Compared with the magnet motor, the torque ripple can be relatively reduced.

In the configuration of the above-mentioned Patent Document 3, it is revealed that the use of the rectangular line causes the winding occupancy ratio in the groove to be increased, and the connection between the coils of the same polarity is continuously connected, thereby eliminating the connection work, thereby improving productivity and reducing the coil end portion. The space occupied.

However, in view of miniaturization and long life of the coil end portion, any of the above-described disclosed examples has not been considered, and in particular, it is possible to achieve an insulation structure of a motor that is downsized and has a long life.

An object of the present invention is to provide a variable frequency motor device including a stator having a small-sized and long-life motor in which a fixed sub-winding of a fractional-slot electric motor is configured to effectively perform insulation of a coil end portion.

The present invention relates to a variable frequency motor device comprising a variable frequency motor device having a motor and a plurality of three-phase inverters, the motor comprising: three-phase stator windings wound in a plurality of slots arranged in a circumferential direction of the motor a stator of a complex array and a rotor having a permanent magnet on the outer circumference, the plurality of three-phase inverters for driving the plurality of three-phase stator windings, wherein: Each of the phase windings constituting the three-phase stator winding is composed of a bare wire of a plurality of circular wires, and the stator windings of the respective groups housed in the plurality of slots are directly connected to the corresponding three-phase inverter, and the plurality of stator windings are connected The straddle portion between the windings is provided with an insulator having a high dielectric strength in a straddle portion contacting the stator windings of the other phases, and the straddle portion between the windings is provided with an insulation strength lower than that of the insulator. Insulation.

Further, the present invention relates to a variable frequency motor device comprising a variable frequency motor device having a motor and a plurality of three-phase inverters, the motor having a three-phase stator winding wound in a plurality of slots toward a circumference of the motor Aligning the stators of the complex array and having permanent magnets on the outer circumference a rotator, the plurality of three-phase inverters for driving the plurality of three-phase stator windings, wherein each phase winding constituting the three-phase stator winding is composed of a bare wire of a plurality of circular wires, and is to be The stator windings of each group housed in the plurality of slots are directly connected to the corresponding three-phase inverter, and the straddle portion between the windings of the plurality of stator windings is straddle between the stator windings accommodated between the plurality of slots An insulator having a high dielectric strength is provided, and an insulator having a lower dielectric strength than the insulator is provided in a straddle portion between stator windings housed between adjacent grooves.

Further, in the variable frequency motor device described above, the length of the traverse portion of the stator winding between the same poles is shortened, and the length of the straddle portion of the stator windings of the other poles is lengthened.

Further, in the variable frequency motor device described above, the extraction of the neutral point is characterized by the center portion of the groove.

Further, in the variable frequency motor device described above, the number of groups of the multi-phase stator windings is at least four or more.

According to the present invention, it is possible to omit the insulation of the straddle portion between the plurality of stator windings, thereby providing a motor having a small coil end portion and a long life.

Further, in addition to the above effects, the length of the straddle portion between the same poles can be shortened, and the coil end portion can be miniaturized. Further, in addition to the above effects, the winding work becomes easier.

Embodiments of the present invention will be described below by way of illustration. A cross-sectional view of a motor of an inverter motor unit according to an embodiment of the present invention is shown in Fig. 2, and a partially enlarged sectional view thereof is shown in Fig. 1. Fig. 3 is a cross-sectional view showing the axial direction of the motor of the variable frequency motor device of the present invention.

In the figure, the motor 1 is composed of a stator 2 and a rotor 3. The stator 2 is composed of a stator core 4, a plurality of slots 4A (S1, S2, ...) provided on the inner circumference of the stator core 4, and stator windings 5 (5A1...) housed in the slots 4A. . Further, the stator 2 is formed to be fixed to the end plate 13 by the fixing sub-pin 11 and the end bracket 12.

On the other hand, the rotor 3 is composed of a permanent magnet 6, a rotor core 7, a shaft 8, a rotor plate 9 that suppresses the axial direction of the permanent magnet 6, and a magnet holding member 10 that supports a radial force applied to the permanent magnet 6. Composition. The rotor 3 is supported by the end plate 13 so as to be rotatable through the bearing 15. Further, the stator 14A of the position detector for detecting the position of the rotor 3 is fixed to the end plate 13, and the rotor 14B of the position detector is fixed to the shaft of the shaft 8, thereby constituting the position detector 14. Here, an example of a resolver is used as the position detector 14 for display.

In the case of a position detector, not only a resolver but also an encoder. Further, the position detector is not disposed inside the motor, but may be disposed at a position outside the detectable end plate or at a rotational position of the rotor.

The stator core 4 is formed by laminating an electromagnetic steel sheet having a thickness of, for example, 0.5 mm, and has a peripheral shape as shown in the drawing, and includes a hole for fixing the pin 11 and a groove 4A for accommodating the stator winding 5, and a permanent magnet constituting the rotor 3. 6 magnetic The stator teeth 4B of the circuit and the stator core base 4C of the outer peripheral portion are formed. Further, the cooling fins may be integrally molded in the outer peripheral portion as needed. The stator core 4 is a laminated member, but the outer peripheral portion thereof may be welded as needed to increase the mechanical strength. Further, it can be additionally formed integrally by the fixing sub-pin 11.

The rotor 3 is composed of a permanent magnet 6 and a rotor core 7 as a magnetic circuit. Generally, the permanent magnet 6 is made of neodymium magnet for miniaturization. The rotor core 7 is produced by molding a metal (magnetic material) or the like. Here, in order to reduce the weight and cooling, as shown in the drawing, the cylindrical portions having the inner circumferential cylindrical portion 7A and the outer circumferential cylindrical portion 7B are formed, and the rotor ribs 7C are connected therebetween. Therefore, the rotor rib 7C is formed to have a vent hole 7D. Thereby, heat generated by the eddy current generated in the permanent magnet 6 or the rotor core 7 can be effectively removed.

Here, the case where the number of slots N of the stator core 4 is 108 and the number of poles P of the rotor 3 is 24 poles is shown. Further, the stator winding 5 of the motor 1 is a three-phase winding, and the number of slots per phase per phase Nspp=N/P/M (where M is the number of phases) is 3/2, which is a fractional groove, not an integer. Here, the number of slots 108 of the stator 2 and the number of poles 24 of the rotor are a structure in which the number of slots 9 and the number of poles of the rotor 2 are repeated 12 times. The groove combination of the number of slots 9 and the number of poles 2 of the rotor as the basic unit of the configuration is the same as that of the second embodiment.

As described above, the advantage of the fractional groove is superior to the so-called integer groove in which the number of slots divided by the number of poles and the number of phases is Nspp is an integer.

(1) due to the poles of the stator windings belonging to one phase with respect to the rotor The phases are different, and therefore have a value that does not lower the winding coefficient of the relative fundamental wave, and can effectively reduce the influence of the influence of the high harmonic. In the case of the electric motor, a motor with less torque ripple can be provided. In addition, it is not necessary to adopt a structure such as a skew to reduce torque ripple, and the number of man-hours can be reduced. In addition, the torque can be increased as compared to an integer slot and a skewed motor.

(2) If the effects of high harmonics are formed the same, the number of slots can be relatively reduced. Since the area of one slot is increased, the occupancy rate can be increased. Further, the reduction in the number of slots reduces the contact area between the stator 5 and the stator core 4, so that the leakage current from the stator winding 5 to the stator core 4 during the operation of the inverter can be reduced, and the life of the insulating material used can be lengthened. Further, since the number of coils of the stator winding can be reduced, the number of manufacturing steps can be reduced, and an inexpensive motor can be formed.

In particular, when used as a drive device such as an electric servo press, the motor is used for a long period of time, and the selection of the fractional groove is extremely important in terms of operation of the inverter and the like.

In the present embodiment, the number of slots of the stator 2 is selected to be 108, and the number of poles of the rotor 3 is 24 poles. The number of slots 108 of the stator 2 and the number of poles 24 of the rotor are 12-fold overlapping structures of the number of slots 9 and the number of poles 2 of the rotor. The 12-fold number is a very important choice. For example, there are 12 sets of stator windings 5 of the electric motor 1 of the same configuration and belonging to the same phase, so that the number of stator windings connectable to one inverter can be drastically changed by changing the number of inverters used.

That is, it can be performed: a stator winding composed of the same bare wire and number of turns For one inverter, the stator windings are connected in series to 12 groups (that is, the whole inverter is used); or for one inverter, the stator windings are connected in series to 6 groups (that is, the whole Use 2 inverters; or 1 inverter, connect the stator windings in series to 3 groups (that is, use 4 inverters in total); or connect the stator windings in series for 1 inverter The selection of 4 groups (that is, the use of 3 inverters in total); or for one inverter, the stator windings are connected in series for 2 groups (that is, the total use of 6 inverters); or for 1 unit For the inverter, connect the stator windings to one group (that is, select 12 inverters for all). In the above, by using 12 inverters, it can be rotated to 12 times the speed compared with the case of using one inverter. Thereby, characteristics of the motor having the same structure can be selected depending on the application, and it can be used as a variable frequency motor device having various types of torque-velocity characteristics.

1, 2, 4, and 5 show that if one stator is connected in series to two inverters (one coil of a U-phase stator winding is 9 slots/three phases, 3), That is, an example in which all six inverters are used.

Since six inverters are used, the average stator winding system is a stator winding that occupies a total range of about 60 degrees. Therefore, in the internal transformation motor, the average stator winding of one inverter is used during winding operation. The amount of the machine is small, and the working space inside the fixed stator can be obtained, and the winding operation becomes easier, so that the productivity can be improved.

In the case of the two inverters shown in the conventional example, since the stator winding connected to one inverter occupies a range of 180 degrees, the winding operation is performed. The amount of stator windings will increase. Thereby, the working space inside the stator is relatively small, and the winding becomes difficult to perform. Thereby, the motor's occupation rate is lowered, and the motor efficiency is lowered. The configuration of four or more inverters is effective in terms of workability and motor characteristics with respect to conventional examples.

The winding configuration method of this embodiment will be described below. In FIGS. 1 and 2, the grooves 4A accommodating the stator windings 5 are sequentially numbered. In Fig. 4, a stator core 4 of the electric motor (shown in Figs. 1 and 2) of the present embodiment, a development view in the circumferential direction of the stator winding 5, and a connection diagram thereof are shown.

Here, the range of three-phase star-shaped junction lines that can constitute two groups is shown. The number of coils of the stator winding 5 is the same as the number of slots, which is 108. In the coil 5A of one stator winding, the conductor 5B of the stator winding which is the outer peripheral portion of the groove is referred to as B, and the conductor 5B of the stator winding which is the inner peripheral portion of the groove is referred to as A. Here, the conductor 5B of one stator winding is formed by an enamel wire (for example, AIW of Φ1) which reaches dozens of plural circular wires. Further, the coil 5A of the stator winding is formed as a conductor 5B having stator windings disposed on the inner and outer circumferences of the plurality of slots, that is, the number of windings having a plurality of turns.

In Fig. 5, the configuration of the stator winding 5 belonging to the W1 phase of the motor of the present embodiment is shown. Since the 108 stator windings 5 are driven by six three-phase inverters, the number of coils of the average one-phase stator winding 5 is six.

The winding configuration of the so-called average per-pole and the number of slots per fraction of the two-pole and nine-slots is described in, for example, "Electrical Mechanical Design Theory" for performing rock roots, and in the 2-pole and 9-slot configuration, The electrical phase difference of the stator winding 5 accommodated in the adjacent groove is set to be 180 × 2 poles / 9 slots and is 40 degrees. because Thus, among the 18 sets of stator windings 5 having the conductors disposed on the outer peripheral side of the slots S1 to S18, the electrical angles closest to the phase are respectively 60 degrees (the reverse phase is also included in the phase band of the three-phase motor). Among the stator windings 5, for example, the coils 5A of the stator windings disposed on the outer peripheral portion of the groove 4A of the W phase ((S1, S2, S6), (S10, S11, S15)) are grouped.

Further, for example, the conductor 5B (S1B) of the stator winding of the outer peripheral portion of the slot S1 should form the inner peripheral portion of the slot of the coil 5A of the stator winding, that is, the conductor 5B of the stator winding, and the slot spacing is selected at an electrical angle. The conductor 5B of the stator winding 5 closest to the slot S5 of 180 degrees (the electrical angle is 160 degrees) or the slot S6 (the electrical angle is 200 degrees). The electrical phase difference is 180 degrees with respect to the reverse phase, and both sides have an interval of 20 degrees, which is the same. However, as shown in the drawing, the inner peripheral portion of the groove S5 of the coil end portion of the stator winding 5, that is, the conductor 5B of the stator winding (S5A) (generally referred to as a short pitch winding) can be shortened.

Therefore, the conductor 5B (S2B) of the stator winding, which is the outer peripheral portion of S2 in this order, should form the inner peripheral portion of the groove of the coil 5A of the stator winding, that is, the conductor 5B of the stator winding, as shown in the figure. The inner peripheral portion of the groove S6, that is, the conductor 5B of the stator winding (S6A) is selected, and the outer peripheral portion of the S3, that is, the conductor 5B (S3B) of the stator winding, in order to form the inner peripheral portion of the groove of the one turn, that is, the stator winding In the conductor 5B, the inner peripheral portion of the groove S7, that is, the conductor 5A of the stator winding is selected as shown in the drawing (S7A).

Therefore, the W-phase stator winding 5 belonging to one inverter is as shown in Figs. 1, 2, 4, and 5, and the conductor 5B of the stator winding of the outer circumference of the slot S1 is connected to the conductor of the stator winding of the inner circumference of the slot S5. 5B (the line of the stator winding The ring 5A1), the conductor 5B of the stator winding of the outer circumference of the groove S2 is connected to the conductor 5B of the stator winding of the inner circumference of the groove S6 (the coil 5A2 of the stator winding), and the conductor 5B of the stator winding of the inner circumference of the groove S10 The conductor 5B (the coil 5A3 of the stator winding) of the stator winding connected to the outer circumference of the groove S6.

Further, the conductor 5B of the stator winding of the outer circumference of the groove S10 is connected to the conductor 5B of the stator winding of the inner circumference of the groove S14 (the coil 5A4 of the stator winding), and the conductor 5B of the stator winding of the outer circumference of the groove S11 is connected to the groove S15. The conductor 5B of the stator winding of the inner circumference (the coil 5A5 of the stator winding) is connected to the conductor 5B of the stator winding of the outer circumference of the slot S15 (the coil 5A6 of the stator winding) by the conductor 5B of the stator winding of the inner circumference of the slot S19.

Here, the conductor 5B of the stator winding on the outer circumference of the groove S1 is a lead wire W1 to the outside, and the conductor 5B of the stator winding on the outer circumference of the groove S15 is a connection point WN1 which is a neutral point, and is connected to other V and U phases. The neutral points are connected. Neutral points and the extraction of the outside can also be reversed. The characteristics of the winding configuration of the fractional groove are as shown in Fig. 4. The case where the number of coils constituting the pole is 2 and the case where it is 1, is not identical.

The configuration of the six stator windings 5 belonging to one phase of the motor is shown in FIG. The structure is shown in Fig. 5 (a), and the cross section is shown in Fig. 5 (b). Fig. 6 is a perspective view showing the winding of Fig. 5(a) viewed obliquely. Each of the coils 5 (5A1 to 5A6) is wound by the same winding method. In the figure, the example shows that each winding is 3 turns, but it can also be 4 turns, and the appropriate number of turns is determined according to the motor specifications.

The stator windings constituting one phase are: coils 5A (5A1, 5A2, 5A3, 5A4, 5A5, 5A6) of 6 stator windings 5 and a straddle portion 5C (5C1) 5C2, 5C3, 5C4, 5C5), a neutral point lead line WN1, and an outer lead line W1 are formed by a plurality of round bare lines. In other words, the configuration is such that a connection portion is not provided in the middle.

In the case where 5C2, 5C3, and 5C5 among the traverse portions 5C of the coil 5A of the stator winding 5 are wound, tens of units of bare conductors of the conductor 5B constituting the stator winding are mounted as shown, for example, a tubular shape. The insulating material 5D is used for insulation treatment with high dielectric strength. Here, in the conductor 5B of the stator winding, an enameled wire of 0.55 mm is formed in 55 pieces, and a varnished glass tube is used as the insulating material 5D. Thereby, it is not necessary to perform the insulation treatment of the straddle portion of the coil end portion which is in contact with the stator winding 5 of the other phase having a large potential difference in the additional work. The wire ends of the wound coils are entangled in a complicated manner, and thus workability is poor, and it is easy to bulge due to the insertion of the insulator. The insulation treatment at the time of winding is excellent in workability, and the insulator can be inserted neatly, and the coil end portion can also be formed into a compact structure.

As described above, the traverse portion 5C between the windings of the plurality of stator windings is housed between the stator windings between the plurality of slots (between S2 and S6 of the coil of the outer peripheral portion in FIGS. 1 and 2, and S6 and S10) The straddle portion between the S10 and S14 is provided with an insulating material 5D having high electrical insulation strength. The stator windings of the other phases are accommodated in the plurality of slots, and the traverse portion is in contact with the stator windings of the other phases.

Further, the straddle portion between the stator windings accommodated between the adjacent grooves (between the grooves S1 and S2 and between S10 and S11) is formed to eliminate the insulation. That is, the bare conductor of the conductor is covered with an insulator such as enamel, and therefore, by using the insulation, the insulator having an electrical insulation strength lower than that of the insulating material 5D is used. The constituents.

As described above, in the present embodiment, the straddle portion between the stator windings accommodated between the adjacent slots (between the slots S1 and S2 and between the slots S10 and S11) is formed to eliminate the new insulation. Thereby, the entire coil end portion can be formed to be simplified, and the entire motor can be miniaturized. Further, since the straddle portion between the stator windings housed between the plurality of slots is provided with the insulating material 5D having high electrical insulation strength, it can be formed to withstand high voltage and long life as compared with a motor without an insulating material. electric motor. In particular, it is suitable for a motor inverter device for an electric servo press device having a large vibration. According to the above configuration, it is possible to provide a small-sized and long-life variable frequency motor device and an electric servo press device on which the device is mounted.

Further, as shown in FIG. 4, the length ratio of the traverse portion 5C (5C1, 5C4) connecting the coils 5A (5A1, 5A2, and 5A4, 5A5) of the stator windings belonging to the same pole will be different. The length of the traverse portion 5C (5C2, 5C3, 5C5) connected between the coils 5A of the stator windings (between 5A2, 5A3, 5A3, 5A4, 5A5, 5A6) is shorter, and the total length of the stator winding 5 can be shortened. Further, it is possible to form an electric motor with high efficiency, and it is possible to eliminate the redundant portion of the traverse portion 5C that connects the coils 5A, so that the coil end space can be reduced, and the motor can be miniaturized.

In the conventional method having the flat-angle winding shown in the above-mentioned Disclosure Example 2 (Patent Document 2), although the winding occupancy ratio in the groove can be improved, the number of rotations is high due to the eddy current in the winding, in the high-frequency field. In the meantime, the resistance is increased, and the copper loss is increased. In addition, since the shape of the coil is formed in a tortoise shape due to the difficulty in deformation of the coil end portion of the rectangular wire, the end of the coil The space becomes large and it is difficult to miniaturize.

In the configuration of the present embodiment, as shown in the figure, a circular bare wire is formed and formed into a substantially rectangular shape, whereby the end portion is easily deformed, and a new insulating portion and an undeveloped portion which are formed across the line are provided. Thereby, the coil end portion can be formed to be simplified, and the motor can be miniaturized. In addition, the eddy current can be reduced and the efficiency in the high speed field can be improved. Further, by effectively arranging the insulation at the end of the coil, it is possible to provide a motor that withstands high voltage and has a long life.

Further, the position W1 of the lead wire which is the W phase in the winding is formed by the outer peripheral portion of the groove, and the position WN1 at the midpoint is also drawn from the outer peripheral portion. However, before the neutral point of the coil 5A6 of the stator winding is taken out in the groove, the coil end portion of the coil end portion on the reverse connection line side is moved to the inner peripheral side, and the coil 5A of the stator winding is housed in the groove. Thereby, it is not taken out from the outer peripheral portion of the stator winding by the outer peripheral portion. Thereby, the lead wire of the neutral point in the winding work and after the work can be stably fixed, and the connection work of the neutral point can be easily performed.

In the above configuration, the stator windings connected to one inverter are housed in the range of about 1/6 of the entire circumference. Therefore, after the coils of the W1, V1, and U1 phases that are continuously wound are accommodated in the stator slots, The following can set the winding space that is sequentially stored by W2, V2, U2 phase to W6, V6, U6. This is effective when the motor to be used is a large-sized motor having an outer circumferential diameter of several hundred mm to 1000 mm and a torque of several kNm. There is a large space on the inner side of the stator, and since the space occupied by one set of star windings is relatively small, the winding work can be easily performed.

The above is explained for the W phase, but the V phase is based on the electricity. Starting from S4 with an angle of 120 degrees, the coils of the six stator windings are sequentially accommodated in a slot that is 120 degrees out of phase with the W phase, so that the U phase can be obtained from the W phase. The grooves S7 having a phase difference of 240 degrees are sequentially stored in the grooves and completed.

Figure 7 shows the construction of a variable frequency motor device in accordance with an embodiment of the present invention. As shown in FIG. 4, the coil 5A of the stator winding of the stator winding 5 corresponding to the four poles of the rotor 3 and the fixed sub-groove of the stator 2 corresponding thereto is set to one set, and each phase is six. In the group, there is no connection portion therebetween, and one of them is connected to the terminals of W, V, and U of the inverter 17, and one of them is connected to the neutral point. That is, the coil group E-1 of the stator winding constitutes a neutral point with U1 as the starting point and ending with UN1, and a neutral point with VN as the starting point and VN1 as the starting point, starting from W1. One winding shaft composed of three coils of a neutral point with WN1 as the end point. Coils E-2, E-3, E-4, E-5, and E-6 are also the same.

Therefore, the inverter 17 is formed in six stages in this embodiment. The rotor 3 has 24 poles on the entire circumference, and the rotor 14B of the position detector is disposed coaxially at the axial end thereof, and the position information θ from the position is transmitted through the holder of the position detector (not shown) to be fixed. Sub side. The inverter 17 has six inverter elements of the same structure.

The inverter 17 is a three-phase configuration as shown in the drawing, and is formed, for example, by an IGBT or the like as the switching element 18. The power supply of the inverter 17 is converted into a direct current by the alternating current power source 19 through the rectifier 20, and a capacitor 21 having a large capacity is connected to the direct current end. In applications such as electric servo presses, the motor 1 is mostly formed at a certain angle. Repeated movement of the range of degrees. At this time, the energy of acceleration and deceleration of the motor 1 is charged and discharged by the capacitor 21, whereby the power supply capacity and the rectifier capacity can be suppressed to be small.

The control system of each of the inverters 17 is substantially the same as the control used for the general AC servo or the like, but in this case, the same current (torque) command Is is supplied to the six inverters 17 in the same manner. 6 times the torque occurs. The rotation angle information θ from the position detector 14B is transmitted through the sine and cosine wave generation circuit 22, and the output is output to the two-phase to three-phase conversion circuit 23, thereby outputting currents corresponding to the respective layers for the U, V, and W phase outputs. Isu, Isv, Isw. The current control systems 24 (ACRU, ACRV, ACRW) of the respective phases are configured by the current commands Isu, Isv, Isw, and the feedback signals Ifu, Ifv, and Ifw from the current detector CT. The current detector CT is shown in three examples, but it may be two.

In addition to the above, the control system of the frequency converter has a method performed by the control system of the d/q axis. This method is not directly related to the present invention, and the detailed description is omitted.

In the above configuration, compared with one large inverter, by using six small-sized inverters 17 having versatility, it is possible to form a cheaper, more productive, and expandable one. system. In addition, there is an advantage that it can be easily performed when the fault occurs or the device is maintained. Here, the six coils forming the one-phase stator winding 5 are configured as one line in the present embodiment without including the connection portion as described above. Therefore, the coils are used as a drive device such as a multi-vibration or electric servo press. When it has the advantages of improved reliability and long life. In addition, because it is a fractional slot, it has the special Sign.

The above is shown by the permanent magnet rotator of the surface magnet, but it may be a permanent magnet rotating machine composed of a so-called embedded rotor embedded in the rotor core. At this time, the magnet system can be held more firmly in the rotor.

Next, a variable frequency motor device according to another embodiment of the present invention will be described. A sectional view of a motor of a variable frequency motor device according to another embodiment of the present invention is shown in FIG. A development view of the circumferential direction of the stator core and the stator winding of the electric motor according to another embodiment of the present invention and a connection diagram thereof are shown in FIG. The configuration of the stator windings belonging to one phase of the electric motor according to other embodiments of the present invention is shown in FIG.

Here, the number of slots N of the stator core is 60, the number of poles P of the rotor 3 is set to 16 poles, and the number of phases M of the stator windings 5 of the motor 1 is set to a general three-phase. That is, the number of slots per phase per phase is NSPP=N/P/M, which is 5/4, and the number of slots 15 and the number of slots of the number of poles of the rotor 4 are four times.

The winding configuration method of the other embodiment will be described below. In FIG. 8, the groove 4A in which the stator winding 5 is accommodated is sequentially numbered. In Fig. 9, a developed view of the stator core 4 and the stator winding 5 in the circumferential direction of the electric motor (shown in Fig. 8) of the other embodiment and a connection diagram thereof are shown. The configuration of the stator winding 5 belonging to the V1 phase of the motor is shown in FIG. Since the stator winding 5 of 60 is driven by four three-phase inverters, the number of coils of the average one-phase stator winding 5 is five.

In the four-pole and 15-slot configuration, the electrical phase difference from the stator winding 5 accommodated in the adjacent groove is 180 × 4 poles / 15 slots, which is 48 degrees. Therefore, in the group 15 having the conductors disposed on the outer peripheral side of the groove S1 to the groove S15 Among the sub-windings 5, the stator windings 5 which enter the closest electrical angle of 60 degrees (including the reverse phase in the phase band of the three-phase motor) are respectively arranged, for example, with respect to the V phase (S1, S2). The coils 5A and 5 of the stator windings on the outer peripheral portion of the groove 4A of S5, S9, and S13 are grouped.

Further, for example, in the case where the conductor 5B of the stator winding of the outer peripheral portion of the slot S1, that is, the inner peripheral portion of the slot of the one turn, that is, the conductor 5A of the stator winding, the slot S5 whose slot angle is the closest to the electrical angle of 180 degrees is selected ( The conductor 5B of the stator winding 5 having an electrical angle of 48 × 4 = 192 degrees). Therefore, the inner peripheral portion of the stator winding, that is, the inner peripheral portion of the slot of the stator winding, which is the outer peripheral portion of S2, in order to form the outer circumference of the slot S2, that is, the conductor 5B of the stator winding, is selected as shown in the figure. The conductors 5B of the stator windings are selected in sequence.

Therefore, the stator winding 5 of the V phase belonging to one inverter is as shown in Figs. 8, 9, and 10. The conductor 5B of the stator winding of the outer circumference of the slot S1 is connected to the conductor 5B of the stator winding of the inner circumference of the slot S5, Further, the conductor 5B of the stator winding of the outer circumference of the groove S2 is connected to the conductor 5B of the stator winding of the inner circumference of the groove S6, and the conductor 5B of the stator winding of the inner circumference of the groove S9 is connected to the stator winding of the outer circumference of the groove S5. Conductor 5B.

Further, the conductor 5B of the stator winding of the outer circumference of the groove S9 is connected to the conductor 5B of the stator winding of the inner circumference of the groove S13, and the conductor 5B of the stator winding of the inner circumference of the groove S17 is connected to the stator winding of the outer circumference of the groove S13. Conductor 5B. Here, the stator winding 5 on the outer circumference of the groove S1 is the outer lead wire V1, and the stator winding 5 on the outer circumference of the groove S13 is a neutral point VN1 for connection with other V and U phases. The neutral points are connected. Neutral points and the extraction of the outside can also be reversed. In addition, if it will be wound When the group is formed into four or more groups, the capacity can be easily realized.

In other embodiments of the present invention, the coils 5A of the five stator windings shown in Fig. 10 are wound by the same winding method. Further, the stator windings constituting one phase are the coils 5A (5A1, 5A2, 5A3, 5A4, and 5A5) of the five stator windings 5, and the traverse portions 5C (5C1, 5C2, 5C3, and 5C4), and the neutral point. The lead line VN1 and the outer lead line V1 are formed by a plurality of conductor bare wires. In other words, the configuration is such that a connection portion is not provided in the middle.

Further, in the 5C2, 5C3, and 5C4 among the traverse portions 5C of the coil 5A of the stator winding 5, the bare conductor wires constituting the conductor 5B of the stator winding, for example, the tubular insulating material 5D, are mounted as shown, thereby eliminating the need for In the subsequent additional work, the insulation of the coil end portion which is in contact with the stator winding 5 having the other phase of the potential difference is effectively matched. Further, as shown in FIG. 10, the length of the traverse portion 5C1 connecting the coils 5A belonging to the same-pole stator windings is longer than the traverse portion 5C2 connecting the coils 5A of the stator windings belonging to the different poles. The lengths of 5C3 and 5C4 are shorter, the total length of the stator winding 5 can be shortened, the motor can be formed as an efficient motor, and the redundant portion of the traverse portion 5C connecting the coils 5A can be eliminated, thereby reducing the coil end portion. Space, the motor can be miniaturized.

In the configuration of the other embodiment of the present invention, as shown in the figure, a circular bare wire is formed and formed into a substantially rectangular shape, whereby the end portion is easily deformed, and the portion where the insulation across the line is provided is not performed. In part, the end of the coil can be simplified and the motor can be miniaturized. In addition, the eddy current can be reduced and the efficiency in the high speed field can be improved. In addition, by effectively at the end The part is equipped with insulation to provide a high-voltage, long-life motor inverter device and an electric servo press device equipped with the device.

1‧‧‧Electric motor

2‧‧‧stator

3‧‧‧Rotor

4‧‧‧ Stator core

4A (S1, S2, ...) ‧‧‧ slots

4B‧‧‧Standard teeth

4C‧‧‧Standard iron base

5‧‧‧ stator winding

5A (5A1, 5A2, 5A3, 5A4, 5A5, 5A6) ‧‧‧ coils of stator windings

5B‧‧‧Conductors for stator windings

5C (5C1, 5C2, 5C3, 5C4, 5C5) ‧‧‧ straddle of the stator winding

5D‧‧‧Tubular insulation

6‧‧‧ permanent magnet

7‧‧‧Rotor core

7A‧‧‧Inner cylindrical part

7B‧‧‧Outer cylindrical part

7C‧‧‧Rotor fins

7D‧‧‧ventilation holes

8‧‧‧Axis

9‧‧‧ rotor plate

10‧‧‧ Magnet holding member

11‧‧‧Fixed sales

12‧‧‧End bracket

13‧‧‧End board

14‧‧‧ position detector

14A‧‧‧ Stator of position detector

14B‧‧‧Rotor of position detector

15‧‧‧ bearing

16A‧‧‧Slot insulation

16B‧‧‧Interlayer insulation

17‧‧‧Inverter

18‧‧‧Switching components

19‧‧‧AC power supply

20‧‧‧Rectifier

21‧‧‧ capacitor

22‧‧‧Sine and cosine wave generating circuits

23‧‧‧Two-phase to three-phase conversion circuit

24‧‧‧ Current Control System

CT‧‧‧ current detector

E1~E6‧‧‧Cable group of stator winding

W1‧‧‧ external lead wire

WN1‧‧‧ lead line for neutral point

Fig. 1 is an enlarged cross-sectional view showing the main part of an electric motor according to an embodiment of the present invention.

Fig. 2 is a cross-sectional view showing the motor of the variable frequency motor unit.

Fig. 3 is a cross-sectional view showing the axial direction of the motor of the variable frequency motor unit.

Fig. 4 is a development view showing the circumferential direction of the stator core and the stator winding of the motor and a connection diagram thereof.

Fig. 5 is a view showing the configuration of a stator winding belonging to one phase of the motor.

Fig. 6 is a perspective view showing the configuration of the stator winding of Fig. 5(a).

Fig. 7 is a view showing the configuration of the variable frequency motor device.

Fig. 8 is a cross-sectional view showing the motor of the variable frequency motor device of another embodiment.

Fig. 9 is a developed view showing the circumferential direction of the stator core and the stator winding of the motor and a connection diagram thereof.

Fig. 10 is a view showing the configuration of a stator winding belonging to one phase of the motor.

1‧‧‧Electric motor

2‧‧‧stator

3‧‧‧Rotor

4‧‧‧ Stator core

4A (S1, S2, ...) ‧‧‧ slots

4B‧‧‧Standard teeth

4C‧‧‧Standard iron base

5‧‧‧ stator winding

5A (5A1, 5A2, 5A3, 5A4, 5A5, 5A6) ‧‧‧ coils of stator windings

5B‧‧‧Conductors for stator windings

5C (5C1, 5C2, 5C3, 5C4, 5C5) ‧‧‧ straddle of the stator winding

5D‧‧‧Tubular insulation

6‧‧‧ permanent magnet

7‧‧‧Rotor core

7A‧‧‧Inner cylindrical part

7B‧‧‧Outer cylindrical part

7C‧‧‧Rotor fins

7D‧‧‧ventilation holes

8‧‧‧Axis

10‧‧‧ Magnet holding member

11‧‧‧Fixed sales

W1‧‧‧ external lead wire

Claims (5)

A variable frequency motor device comprising a motor and a plurality of three-phase inverters, wherein the motor is provided with a three-phase stator winding wound in a plurality of slots arranged in a circumferential direction of the motor a stator, and a rotor having a permanent magnet on the outer circumference, the plurality of three-phase inverters for driving the plurality of three-phase stator windings, wherein each phase winding constituting the three-phase stator winding is composed of a plurality of The bare wire of the shaped wire is formed, and the stator windings of each group accommodated in the plurality of slots are directly connected to the corresponding three-phase inverter, and the straddle portion between the windings of the plurality of stator windings is in contact with the stator of the other phase The traverse portion of the winding is provided with an insulator having a high dielectric strength, and the traverse portion between the windings is provided with an insulation having a lower insulation strength than the insulator. A variable frequency motor device comprising a motor and a plurality of three-phase inverters, wherein the motor is provided with a three-phase stator winding wound in a plurality of slots arranged in a circumferential direction of the motor a stator, and a rotor having a permanent magnet on the outer circumference, the plurality of three-phase inverters for driving the plurality of three-phase stator windings, wherein each phase winding constituting the three-phase stator winding is composed of a plurality of The bare wire of the shaped wire is formed, and the stator windings of each group accommodated in the plurality of slots are directly connected to the corresponding three-phase inverter, and the traverse between the windings of the plurality of stator windings An insulator having a high dielectric strength is provided in a straddle portion between stator windings housed between the plurality of slots, and a dielectric strength of the straddle portion between the stator windings accommodated between the adjacent slots is lower than the insulator Insulation. The variable frequency motor device according to claim 1 or 2, wherein the length of the traverse portion of the stator winding between the same pole is shortened, and the length of the traverse portion of the stator winding of the other pole is lengthened. The variable frequency motor device according to claim 1 or 2, wherein the extraction of the neutral point is taken out from the center of the groove. The variable frequency motor device according to claim 1 or 2, wherein the number of sets of the multi-phase stator windings is at least four or more.