WO2011029228A1

WO2011029228A1 - Square-wave three-phase brushless permanent magnet direct current motor provided with large-teeth-and-small-teeth structure and assembling method thereof

Info

Publication number: WO2011029228A1
Application number: PCT/CN2009/073869
Authority: WO
Inventors: 漆亚梅; 李铁才; 汤平华; 杨贵杰
Original assignee: 深圳航天科技创新研究院
Priority date: 2009-09-11
Filing date: 2009-09-11
Publication date: 2011-03-17
Also published as: CN102124632B; CN102124632A

Abstract

A square-wave three-phase brushless permanent magnet direct current motor provided with a large-teeth-and-small-teeth structure and the assembling method thereof. The number of the magnetic poles on a rotor core is 2P. The number of the slots in a stator core is Z. Z teeth on the stator core are composed of Z/2 large teeth (6) and Z/2 small teeth. An insertion slot (11) is provided on each yoke between two adjacent large teeth (6). Each small tooth is formed by inserting an end part of each small tooth core (8) into one of the insertion slots (11). Each large tooth (6) occupies an electrical circumferential angle falling within a range of 150°～234°. Each small tooth together with the notches on its two sides occupies an electrical circumferential angle falling within a range of 90°～6°. The sum of the electrical angles of one large tooth (6) and one small tooth is 240°. Three-phase windings are wound on Z/2 large teeth (6) separately, and Z/6 concentrated windings are arranged at each phase. During assembling, firstly, the windings are wound on the large teeth (6) separately, and then the small teeth are embedded. It is convenient to wind the windings in the motor. The motor can be used as a servo motor or a torque motor.

Description

Square wave three-phase brushless permanent magnet DC motor with large and small tooth structure and assembly method thereof

The present invention relates to a large-diameter permanent magnet motor, and more particularly to a square-wave three-phase brushless permanent magnet DC motor having a large-tooth structure and an assembly method thereof. This type of motor can be used as a servo motor or a torque motor. Background technique

The permanent magnet motor can be divided into two major categories: sine wave and square wave according to the driving current and back electromotive waveform. Generally, a sine wave permanent magnet motor is called a permanent magnet homogen motor (PMSM), or a sine wave AC servo motor. Another type of square wave permanent magnet motor is called a square wave brushless DC motor (BLDCM).

Permanent magnet motors are reversible and can be used both as electric motors and as generators. The square wave permanent magnet generator has a larger output than the sine wave permanent magnet generator by π /2 , which is 1.57 times.

During the 1980s, square wave permanent magnet motors have been widely used. The external characteristics of square wave permanent magnet motors are basically the same as those of brushed DC motors. The control is relatively simple, but its biggest disadvantage is the existence of large principle commutation torque fluctuations. In this regard, the researchers proposed a variety of compensation measures, but the actual application results are not satisfactory.

Since the torque fluctuation of sinusoidal permanent magnet motor is much smaller than that of square wave permanent magnet motor, in the precision servo drive application in the 1990s, square wave permanent magnet motor was gradually replaced by sine wave permanent magnet motor, which has become a modern industrial application. Mainstream. However, sinusoidal permanent magnet motors lead to a significant increase in the complexity of the control system and a significant increase in cost. More importantly, the force performance of the motor is drastically reduced.

On the other hand, the traditional square wave brushless DC motor and its control technology have been recognized as mature, and due to the aforementioned defects, it has been limited to applications where the requirements are not high, and there have been few studies at home and abroad.

The ideal motor should have the characteristics of small volume, large torque, small torque fluctuation, high efficiency and low cost. However, in the real world, it is often only possible to balance this concept. When designing high-performance servo motors, the priority is motion control performance, power, size, efficiency, and price. The servo motor must overcome the cogging effect and have small positioning torque, torque fluctuation or speed fluctuation, which can drive continuously and stably under low speed and large torque. There are many reasons for the torque fluctuations that occur. It is generally believed that the main causes are: the positioning torque generated by the cogging, the non-sinusoidal distribution of the air gap magnetic field and the non-sinusoidal current of the three-phase current. The cogging effect directly generates the positioning torque fluctuations related to the number of teeth and slots; the non-sinusoidal distribution of the air gap magnetic field generates the harmonic potential of the back EMF (MMF) harmonics and current harmonics; therefore, the torque fluctuation of the servo motor is caused by: Each positioning torque and harmonic torque are composed. The main harmonic order is related to the number of teeth, the number of slots, the number of poles and their multiplication, the multiplier, and the number of beats.

The large pole motor involved in the invention is also called a concentrated winding motor, which has the characteristics of small winding end, small copper consumption, simple structure and low production cost, and has developed rapidly in the past ten years. Generally, the motor that defines the number of slots per phase per phase q = S / (2Pm) is less than or equal to 1/2 is a large pole motor or a concentrated winding motor, where S is the number of slots, m is the number of phases, and P is the pole pair . Figure 1 shows an 8-pole, 9-slot, large-pole, three-phase permanent magnet brushless motor. There are 4 N poles and 4 S poles arranged at intervals of 8 poles; there are 9 slots correspondingly, and each slot contains half of the adjacent two windings. For example, the uppermost N pole is facing one tooth, the left side is the A+ winding, and the right side is the A-winding. Wherein, the electrical distance of the slot is:

4 x 360

a - - = 160

9

. , 3 x 20 ,

Sm (丁)

^K dl = · = 0.960

20

The 3 sin pitch factor is:

K,

Pi = sin(—x 90) = 0.985

9

K : ^K dl ^K pl 0.946 Main positioning torque times:

=Polar slot /C=8 X 9/1=72 In the above formula, C is the minimum common divisor of the number of poles and slots. The ratio of the number of times Kc to the number of poles is 8/72 = 1/9, that is, the number of positioning moments is 9 times that of the fundamental wave. It is generally considered that the magnitude of each positioning torque is The value of the number of times is inversely proportional, or the magnitude of each positioning torque is considered to be no more than 1/9 of the fundamental torque of each phase. Therefore, the design principle of the cogging is that the number of times the minimum positioning torque is required is as large as possible with respect to the number of fundamental torques. The cogging fit also affects the material utilization of the motor, ie the winding factor, which requires a winding factor close to one.

Winding Coefficient and Number of Positioning Torques of Several "Big Pole Motors"

In the invention patent application of the publication No. CN101030721A, a cogging solution scheme in which the pole and groove values have no common number is disclosed (for example, 21 slots 26 poles, 33 slots 38 poles or 40 poles). In addition, the applicant's patent application No. CN1856921A discloses a permanent magnet motor having a ratio of a groove to a magnetic pole greater than 0.75 and less than 1.0 (for example, 36 slots 46 poles, 30 slots 38 poles). Such permanent magnet motors aim to obtain a sinusoidal air gap magnetic field and a small positioning torque. Unfortunately, the method of using only the cogging is limited, and the cogging effect is still relatively large. Achieve a (5~1)% level of rated torque.

The above "big pole motor" has been applied in different occasions. However, the effect of reducing the positioning torque simply by the cogging is still unable to meet the requirements of the servo motor. Therefore, a large number of methods for reducing the positioning torque by homogenizing the air gap reluctance are generated, including: 1) ironless permanent magnet motor; 2) non-cogging permanent magnet motor; 3) stator chute or permanent magnet 4) reduce the stator slot; 5) permanent magnet surface chamfering, sinusoidal, uneven air gap, permanent magnet short distance, etc. cause the air gap magnetic field sinusoidal; 6) the stator slots are not equidistantly distributed 7) The stator uses fractional slots per phase per phase; 8) increases the number of slots per pole; 9) adds air gap; 10) reduces magnetic load.

The above methods have their advantages and disadvantages, such as: adding air gap, reducing magnetic load, using ironless permanent magnet motor and non-cogging permanent magnet motor, resulting in a decrease in electromagnetic load and power density of the motor, and causing the air gap magnetic field to be sinusoidal Adopting a stator chute or a permanent magnet rotor or a stator using a fractional tank method per phase per phase, which increases the production cost, reduces the material utilization rate, and causes the air gap magnetic field to be sinusoidal. Reducing the stator slots increases the leakage flux and causes the losses to increase. Permanent magnet surface chamfering, sinusoidal, uneven air gap, permanent magnet Short-range and the like cause the air gap magnetic field to be sinusoidal. The purpose of the unequal distribution of the slots of the stator is also to make the air gap magnetic field sinusoidal. The above method is a traditional effective method for sine wave servo motors. However, the traditional methods are not applicable to square wave servo motors.

In the utility model patent ZL 200720070700. 3, a low-fluctuation permanent magnet brushless motor having an unequal width structure is disclosed, wherein the tooth width of the stator teeth is larger or smaller than the tooth width of the adjacent teeth or the groove width of the stator slot is larger than Or less than the groove width of the adjacent groove; or the magnetic pole width of the rotor core is greater or smaller than the width of the adjacent magnetic pole or the spacing between the magnetic poles of the rotor core is greater or smaller than the spacing between adjacent magnetic poles. In general, the use of different size teeth (unequal width teeth) stator core design may affect the number and magnitude of positioning torque. Improper design will result in greater positioning torque. The utility model patent also adds a rotor core magnetic pole unequal width method at the expense of generating a motor back EMF asymmetry. The utility model patent also adds a method of eccentricity of the inner surface of the stator core, which is also costly to produce a motor back electromotive force. The motor back EMF asymmetry is a fatal flaw for servo motors. The target of this utility model patent is a low-power variable speed drive motor with low performance. Summary of the invention

The invention solves the problems existing in the existing square wave permanent magnet motor and the sine wave permanent magnet motor, and proposes a new principle, a new structure, a high performance and a low cost large square wave permanent magnet motor.

The technical solution of the present invention is to provide a square wave three-phase brushless permanent magnet DC motor having a large-tooth structure, wherein a rotor core of the motor is provided with a plurality of pairs of permanent magnets, and a stator of the stator is provided with a three-phase winding, wherein The number of slots Z on the stator core and the number of poles 2P on the rotor core have the corresponding relationship shown in the following table, corresponding to Z stator slots, corresponding to Z teeth, including Z/2 large teeth, Z/2 small teeth:

The three-phase winding comprises Z/2 concentrated windings, respectively wound around Z/2 large teeth, each phase has Z/6 concentrated windings, and the arrangement order of the concentrated windings and teeth is: A phase on the large teeth Concentrated winding, a small tooth, a large tooth, a B phase concentrated winding, a small tooth, a large tooth, a C phase concentrated winding, a small tooth, and the like; wherein, the stator core includes a large tooth core and Z/2 a separate small-toothed iron core, a yoke portion between each adjacent two large teeth is provided with a plunging groove, and a total of Z/2 intrusion grooves, each of which is inserted into the small tooth core through its tail One of the large tooth cores is inserted into the groove to form Z/2 small teeth. In a preferred embodiment of the present invention, the slot width between the adjacent large and small teeth on the stator core is 0.1 to 3.0 mm; each large tooth occupies a circumferential electrical angle of 150 to 234, each The small teeth plus the slots on both sides occupy a circumferential electrical angle of 90°~6°, and the sum of the electrical angles of one large tooth and one small tooth is equal to 240°. In order to further reduce the positioning torque, a more preferable solution is that each of the large teeth occupies a circumferential electrical angle of 195° to 205°, and each of the small teeth plus the slots on both sides thereof occupy a circumferential electrical angle of 45° to 35°.

In another preferred embodiment of the present invention, a slot width of a slot between adjacent large teeth and small teeth on the stator core is 0.1 to 3.0 mm _; when Z/2 is an even number, the large teeth are in Z /4 are the first large teeth with a circumferential electrical angle of 224 ° ± 2 °, and the other Z/4 are the second largest teeth with a circumferential electrical angle of 192 ° ± 2 °; each small tooth plus its two sides groove The mouth occupies a circumferential electrical angle of 32° ± 2°; the order of arrangement between the teeth is: a first large tooth, a small tooth, a second large tooth, a small tooth, and so on; and a group of first large teeth The sum of the small electric teeth, the second large teeth and the small teeth occupying the circumferential electrical angle is 480 °.

In the present invention, the large tooth core may be an integral integral large tooth core; or may be composed of Z/2 single large tooth cores of the same structure, between two adjacent large teeth cores The two large teeth of the stator slot center line are spliced to each other.

In the present invention, the permanent magnets N and S of the rotor core are arranged in phase, and the permanent magnet is a radially magnetized tile-shaped magnetic steel or a parallel magnetized tile-shaped magnetic steel. The magnetic steel is an equal radius tile-shaped magnetic steel or a chamfered tile-shaped magnetic steel; the physical air gap between the stator and the rotor is 0.2 to 3 mm; the pole pitch of the permanent magnet on the rotor core is (1 to 0.8) Χ πΟ/4, where D is the outer diameter of the rotor; and further includes a rotor position sensor made of a Hall position sensor, the magnetic sensitive direction of the Hall position sensor is consistent with the normal direction of the rotor, and is mounted on the stator bracket Above, and maintain an air gap of 1~3mm between the rotor and the permanent magnet outer circle.

In the present invention, Z/6 concentrated windings belonging to the same phase may be sequentially connected in series in a circumferential sequence and then drawn out to form a group of A-A ', B-B', C-C three-phase windings. For the motor with the result of Z/6 being greater than or equal to 4, the Z/6 concentrated windings belonging to the same phase can be connected in parallel to Z/12 parallel units, and then connected in series to form a Group A-A', B-B', C-C' three-phase windings. Z/6 concentrated windings belonging to the same phase can also be separately led out to form Z/6 group A-A', B-B', C-C three-phase windings.

The present invention also provides an assembly method for the foregoing motor, wherein when the large tooth core is one In the case of a bulky large-toothed iron core, after the large-toothed iron core is made, the large teeth are first insulated, and then the winding machine is used to wind the concentrated winding on Z/2 large teeth, and then Z/ Two of the small tooth cores are respectively embedded in the Z/2 intrusion grooves of the large tooth core, that is, the stator cores having Z/6 concentrated windings per phase.

The present invention also provides another assembly method for the foregoing motor, wherein when the large tooth core is composed of Z/2 single large tooth cores, the individual large tooth cores are separately insulated first. After processing, the winding machine is used to wind the concentrated windings on the individual large tooth cores, and then the Z/2 single large tooth cores and the three small tooth cores are pressed into the A phase single large tooth iron. Core-small-toothed core-B-phase single-toothed iron core-small-toothed iron core→(the order of single-toothed large-toothed iron core and small-toothed iron core, assembled in sequence to form a stator with Z/2 concentrated windings Iron core.

It can be seen from the above scheme that the small teeth in the present invention are embedded structures, and the small teeth are not installed first, leaving a space for the winding of the concentrated windings to be very convenient, and the automatic winding of the machine can ensure a tank full rate of more than 85%. As a motor, its output is 33% larger than that of a conventional sine wave permanent magnet servo motor, and the winding end is more than three times smaller than a conventional sine wave permanent magnet servo motor, so the copper consumption is greatly reduced. When the motor is driven by three-phase square wave current, it can produce a stable torque, and its torque fluctuation index is equivalent to that of a sine wave permanent magnet servo motor. DRAWINGS

The present invention will be further described with reference to the accompanying drawings and embodiments in which:

1 is a schematic view showing the structure of a stator and a rotor of an 8-pole 9-slot motor in the prior art; FIG. 2A is a schematic view showing the structure of the stator and the rotor of the motor in a preferred embodiment of the present invention; FIG. 2B is another embodiment of the present invention. Schematic diagram of the stator and rotor deployment structure of the first and second large teeth motors;

3 is a schematic view showing the structure of a motor assembly in a preferred embodiment of the present invention;

4A is a schematic view showing the angular distribution of the stator teeth and the grooves in the embodiment shown in FIG. 2A;

4B is a schematic view showing the angular distribution of the stator teeth and the grooves in the embodiment shown in FIG. 2B;

Figure 5A is a schematic view showing the structure of the integrated integral large tooth core;

Figure 5B is a schematic structural view of a small tooth core;

5C is a schematic view showing a fitting structure of a unitary integral large tooth core and a plurality of small tooth cores; FIG. 6 is a schematic structural view of a block type stator core according to another embodiment; FIG. 7 is a schematic diagram showing six concentrated windings connected in parallel in two steps in sequence according to an embodiment of the present invention. detailed description

3 shows a general assembly structure of a motor in a preferred embodiment of the present invention. The main components of the motor include a rotating shaft 30, a rotor 1, a stator 2, etc., and a physical air gap 5 between the rotor 1 and the stator 2 is 0.2 to 3 mm. . The Hall position sensor is used as the rotor position sensor, and the magnetic sensitive direction of the Hall position sensor is consistent with the normal direction of the rotor, and is mounted on the stator bracket 20 and maintained with the outer circumference of the rotor magnet (ie, the permanent magnet). ~3mm air gap. In the present invention, the number of slots Z on the stator core and the number of poles 2P on the rotor core have a correspondence relationship as shown in the following table, wherein when the number of slots is 18, the number of magnetic poles is 12; when the number of slots is 24 , the number of magnetic poles is 16; when the number of slots is 30, the number of magnetic poles is 20; when the number of slots is 36, the number of magnetic poles is 24; corresponding to Z stator slots, there are corresponding Z teeth, including Z/2 large teeth, Z/2 small teeth:

In the following description, taking Z=36 as an example, the number of magnetic poles is 2P=24. Since the number of slots of the motor is large, if the ring structure corresponding to the object is not clearly displayed for the matching structure between the teeth, the groove, the magnetic pole, etc., the expansion shown in Fig. 2 is drawn here. The structure is equivalent to the inner ring of the stator 2 and the outer ring of the rotor 1 of the ring structure. Among them, 12 pairs of 24 permanent magnets, that is, 24 magnetic poles, are arranged on the rotor core, and they are arranged in the N and S phases shown in Fig. 2 to generate an air gap magnetic field. In a specific implementation, the permanent magnet may be a radially magnetized tile-shaped magnetic steel or a parallel magnetized corrugated magnetic steel. The pole pitch of the permanent magnet on the rotor core is (1~0.8) Χ πΟ/4, where D is the outer diameter of the rotor.

At the same time, the number of slots of the stator core Ζ=36 corresponds to 36 slots and 36 teeth; as shown in FIG. 5C, the width of the slot of the stator slot 4 (ie, between the adjacent large teeth and the lower end of the small teeth) The gap is 0. l~3mm _; 36 teeth include 18 large teeth and 18 small teeth, and are arranged in the order of large teeth, small teeth, one large tooth and one small tooth in the circumference. In this embodiment, the three-phase winding includes (Z/2=36/2) = 18 concentrated windings, respectively, using a winding machine The sub-winding winding winding machine is directly wound on the large teeth after the insulation treatment. The order of the concentrated windings and the teeth is as follows: the large-toothed A-phase concentrated winding, one small tooth, one large tooth, the B-phase concentrated winding, one small tooth, one large tooth The C-phase concentrated winding has a small tooth on the tooth, and so on; it can be seen that the motor has 18 concentrated windings, and each of the three phases A, B, and C has six concentrated windings.

As can be seen from Fig. 4A, each large tooth occupies a circumferential electrical angle of 150° to 234°, and each small tooth plus its two sides of the slot occupies a circumferential electrical angle of 90° to 6°, and one large tooth and one small tooth The sum of the electrical angles is equal to 240°. In order to further reduce the positioning torque, each large tooth preferably occupies a circumferential electrical angle of 195° to 205°, and each of the small teeth plus the notches on both sides preferably occupy a circumferential electrical angle of 45° to 35°.

As can be seen from FIG. 4B, in another embodiment, when Z/2 is an even number, Z/4 of the large teeth are the first large teeth occupying a circumferential electrical angle of 224° ± 2 °, and the other Z/4 are The second largest tooth occupying a circumferential electrical angle of 192 ° ± 2 °; each small tooth plus its two sides of the slot occupy a circumferential electrical angle of 32 ° ± 2 ° _; the order between the teeth is: the first large tooth is small a second large tooth, a small tooth, a first large tooth, a small tooth, a second large tooth, a small tooth, and the like; and an adjacent group of the first large tooth, the small tooth, the second large tooth, and the small tooth The sum of the circumferential electrical angles is 480 °.

As shown in FIG. 5A, FIG. 5B, and FIG. 5C, the stator core includes an integral integral large tooth core 9 and 18 small tooth cores 8; and 18 large teeth 6 are provided on the large tooth core. The yoke portion between the adjacent two large teeth is respectively provided with a plunging groove 11 having a total of 18 plunging grooves; each of the small tooth cores 8 is inserted into one of the large tooth cores 9 through the tail thereof. Into slot 1 1.

In a specific implementation, the large tooth core 9 is composed of a plurality of large-tooth silicon steel sheets, and the yoke portion and the tooth portion of each of the large-tooth silicon steel sheets are provided with positioning blind holes 12 through which the multi-layer large-tooth silicon steel sheets are riveted. Into the overall structure. Similarly, each of the small tooth cores 8 is composed of a plurality of small-tooth silicon steel sheets; each of the small-tooth silicon steel sheets 10 is also provided with a positioning blind hole 12 through which the multi-layer small-tooth silicon steel sheets are riveted into a unitary structure. . In this embodiment, the large-toothed iron core 9 and the respective small-toothed iron cores 8 have the same number of layers of silicon steel sheets.

As can be seen from Fig. 5A, the intrusion groove 11 is a dovetail structure having a large inner portion and a small mouth portion; accordingly, the tail portion of each of the small tooth cores 8 in Fig. 5B is also a dovetail structure, which can be exactly the same as Engage in slot 11 to engage.

In the specific assembly, for the integrated integral large tooth core, after the large tooth core is made, the large teeth are insulated, and then the winding machine is used to wind the concentrated winding on 18 large teeth, and then Will have 18 small teeth The iron cores are respectively embedded in the 18 intrusion grooves of the large tooth core, that is, the stator cores having six concentrated windings per phase. In order to make the winding more convenient, in the embodiment shown in FIG. 6, the integral large tooth core 9 having 18 large teeth is centered on the stator groove between two adjacent large teeth (ie, each intrusion groove) The center line is divided into 18 parts for the reference and becomes 18 single large tooth cores. During assembly, the 18 individual large tooth cores are insulated, and then the winding machine is used to wind the concentrated windings on the 18 single large tooth cores, and then the 18 concentrated windings are wound. Large tooth core with 18 small tooth cores, according to phase A, large tooth core, small tooth core, B phase, large tooth core, small tooth core, C phase, single tooth core The sequence of the small tooth cores is assembled in sequence to form a stator core having 18 concentrated windings.

Among them, 18 single large tooth cores have the same structure, which is easy to process and produce. Then, 18 single large tooth cores can be buckled into a complete large tooth core by setting bosses and recessed holes. For example, the snap structure shown in FIG. 6 of the patent No. CN101371425A is used. After the above winding and assembly are completed, the six concentrated windings belonging to the same phase can be connected in series in a circumferential sequence and then lead out to form a group of A-A', B-B', C-C' three-phase windings.

As shown in Fig. 7, six concentrated windings belonging to the same phase can be connected in parallel to two parallel units, and then connected in series to lead out, forming a group of A-A', B-B', C-C'. Three-phase winding. For the case where the number of slots is Z=18, since only 18/6=3 windings per phase, this parallel and string combination connection cannot be realized. It should be noted that when the first and second large teeth are included, two first large tooth concentrated windings are connected in parallel, or two second large tooth concentrated windings are connected in parallel, thereby ensuring two parallel connections. The concentrated potentials of the concentrated windings are the same.

In addition, six concentrated windings belonging to the same phase can be separately led out to form six sets of A-A', B-B', and C-C' three-phase windings. In the present invention, the sum of the electrical angles of a large tooth and a small tooth is equal to 240°, and the magnetic pole covering technique in the range of the electrical angle of 150° to 234° is used to make the air gap magnetic field have a flat top area of 120° or more; The non-uniform cogging and the magnetic balance small teeth are adopted, and the small tooth electric angle of 90°~6° minimizes the positioning torque. Correct In this square wave three-phase brushless permanent magnet DC motor, the magnetic pole covers up to 120. Above, the winding pitch coefficient k _pl = l. Therefore, the winding coefficient k _wl = k _dl X k _pl = l of the square wave three-phase brushless permanent magnet DC motor. More importantly, after the magnetic pole is covered, the armature reaction of the motor is globally magnetized, thereby greatly optimizing the armature reaction of the motor.

The controller of the motor of the invention can adopt the new concept of square wave brushless motor continuous current sampling and closed loop control, and its comprehensive performance exceeds the sine wave AC servo system. The square wave three-phase brushless permanent magnet DC motor can replace the existing sine wave AC servo motor and its servo unit, and become the main branch of the future servo motor and its servo unit. The invention develops an asymmetric slot large pole motor based on the large pole motor. The asymmetric winding large pole motor has a concentrated winding coefficient of 1, and the pole/slot ratio is 2/3. The number of teeth of the large pole motor is the number of slots, of which 1/2 of the teeth have concentrated windings, and 1/2 of the teeth are none. Concentrate the small teeth of the winding, so the number of slots per phase per pole is q = Z / ( 2P XM ) = 1 / 9. The asymmetric slot large pole motor has a large winding coefficient, a small number of concentrated windings, a large reduction in copper consumption, a significant improvement in the armature reaction of the motor, and a greatly simplified motor manufacturing process.

The core magnetic density of the large pole motor of the invention is lower than that of the conventional motor, and the maximum frequency of the iron core should not be higher than 400 Hz. Therefore, the maximum speed of the motor is n _max = 60 f / P = 24000 / p.

The large pole motor of the invention can be applied to industrial fields and civil fields, and mainly includes:

High-precision CNC machine tools, robots, high-precision measuring equipment;

Large and difficult to deform metal extrusion machine, vertical spinning machine, large precision die forging equipment;

High-efficiency, high-precision equipment for heavy-duty CNC machine tools (such as five-axis linkage super heavy-duty CNC boring and milling machine, five-axis linkage super heavy-duty propeller blade machining machine), wind power, metallurgy, automotive, etc.; Light alloy materials (aluminum, magnesium) Forming and processing equipment, stamping automatic line, precision casting automatic line, robot armored automation equipment, robotic spray equipment, assembly automation equipment; high-precision, high-speed, complete manufacturing equipment required for electronic and communication equipment manufacturing, including Special equipment for machine dressing (automatic placement machine, high-precision large-size automatic printing machine, high-speed component insertion equipment, high-speed drilling equipment for circuit boards), special production equipment (lithography machine, metal organic chemical parts extension, lake Product, etching system), and other generalized numerical control machinery, such as textile machinery, printing machinery, packaging machinery, medical equipment; Semiconductor equipment, plastics, rubber machinery, postal machinery, automated production lines, various specialized equipment and other fields.

Industrial robots and robots, such as splicing robots, dispensing robots, handling robots, pick-and-place robots, plug-in robots, packaging robots, chemical bioanalytical robots, medical instrument robots, motion simulation platforms, etc.;

Various control systems and equipment in the aerospace and military fields.

Claims

Rights request

1. A square wave three-phase brushless permanent magnet DC motor having a large-tooth structure, wherein a rotor core of the motor is provided with a plurality of pairs of permanent magnets, and a stator of the stator is provided with a three-phase winding, wherein

Among them, the number of slots Z on the stator core and the number of poles 2P on the rotor core have the corresponding relationship shown in the following table, corresponding to Z stator slots, corresponding to Z teeth, including Z/2 large Teeth, Z/2 small teeth, and the large teeth and small teeth are arranged at intervals:

The three-phase winding comprises Z/2 concentrated windings, respectively wound around Z/2 large teeth, each phase has Z/6 concentrated windings, and the arrangement order of the concentrated windings and teeth is: A phase on the large teeth Concentrated winding a small tooth and a large tooth on the B phase concentrated winding a small tooth a large tooth on the C phase concentrated winding a small tooth, and so on;

Wherein, the stator core comprises a large tooth core and Z/2 independent small tooth cores, and a yoke portion between each adjacent two large teeth is provided with a plunging groove, and a total of Z/2 锲Into the groove, each of the small tooth cores is inserted into one of the large tooth cores through its tail to form Z/2 small teeth.

2. The large-pole square wave three-phase brushless permanent magnet DC motor according to claim 1, wherein the large tooth core is an integral integral large tooth core; or the large tooth iron The core is composed of Z/2 single large tooth cores of the same structure, and the adjacent two single large tooth cores are spliced to each other at the center line of the stator grooves of the two large teeth.

3. The square wave three-phase brushless permanent magnet DC motor of the large and small tooth structure according to claim 2, wherein a slot width of a slot between adjacent large teeth and small teeth on the stator core is 0.1~ 3.0mm; each large tooth occupies a circumferential electrical angle of 150°~234°, and each small tooth plus its two sides slots occupy a circumferential electrical angle of 90°~6°, and the electrical angle of one large tooth and one small tooth The sum is equal to 240°.

The square wave three-phase brushless permanent magnet DC motor of the large and small tooth structure according to claim 2, wherein a slot width of a slot between adjacent large teeth and small teeth on the stator core is 0.1~ 3.0mm _; when Z/2 is even, Z/4 of the large teeth are the first large teeth with a circumferential electrical angle of 224 ° ± 2 °, and the other Z/4 are the circumferential electrical angle 192 ° The second largest tooth of ± 2 °; each small tooth plus the slot on both sides accounts for 32° ± 2° of the circumferential electrical angle _; the order of the teeth is: first large tooth → small tooth second Large teeth, small teeth, and so on; and adjacent groups of first large teeth, small teeth, second large teeth, small The sum of the teeth's circumferential electrical angles is 480°.

The square-wave three-phase brushless permanent magnet DC motor according to claim 2, wherein the permanent magnets N and S of the rotor core are arranged in phase, and the permanent magnet is radial a magnetized tile-shaped magnetic steel, or a parallel-magnetized tile-shaped magnetic steel, the tile-shaped magnetic steel being an equal-radius-shaped magnetic steel or a chamfer-shaped magnetic steel;

The physical air gap between the stator and the rotor is 0.2~3 mm;

The pole pitch of the permanent magnet on the rotor core is (1~0.8) Χ πΟ/4, where D is the outer diameter of the rotor; wherein the rotor position sensor made of the Hall position sensor is further included, the Hall position The magnetic sensitive direction of the sensor is consistent with the normal direction of the rotor, and is mounted on the stator support and maintains an air gap of 1 to 3 mm between the outer circumference of the permanent magnet of the rotor.

6. A square wave three-phase brushless permanent magnet DC motor according to claim 2, wherein Z/6 concentrated windings belonging to the same phase are sequentially connected in series in a circumferential sequence and then led out to form a group A. -A', B-B', C-C' three-phase windings.

7. A square wave three-phase brushless permanent magnet DC motor having a large-tooth structure according to claim 2, wherein the motor having a double number greater than or equal to 4 for Z/6 is Z/ of the same phase. The six concentrated windings are connected in parallel to form Z/12 parallel units, and then connected in series to lead out, forming a group of A-A', B-B', C-C' three-phase windings.

8. A square wave three-phase brushless permanent magnet DC motor according to claim 2, wherein Z/6 concentrated windings belonging to the same phase are separately led out to form a Z/6 group A-A'. , B-B', C-C' three-phase winding.

A method for assembling a square wave three-phase brushless permanent magnet DC motor according to any one of claims 2-8, characterized in that, when the large tooth core is integrated In the case of a large-toothed iron core, after the large-toothed iron core is made, the large teeth are first insulated, and then the winding machine is used to wind the concentrated windings on Z/2 large teeth, and then Z/2 The small tooth cores are respectively embedded in the Z/2 intrusion grooves of the large tooth core, that is, the stator cores having Z/6 concentrated windings per phase.

10. A method of assembling a square wave three-phase brushless permanent magnet DC motor according to any one of claims 2-8, wherein when the large tooth core is Z/2 When a single large tooth core is composed, the individual large tooth cores are separately insulated, and then the winding machine is used in each monomer. The concentrated winding is wound on the large tooth core, and then the Z/2 single large tooth core and the three small tooth cores are in the A phase. The large tooth core is a small tooth core → the B phase monomer is large. The tooth core has a small-toothed iron core, a C-phase single-toothed iron core, and a small-toothed iron core in sequence, which are assembled in sequence to form a stator core having Z/2 concentrated windings.