Six-phase motor

Abstract

The present invention relates to a six-phase motor comprising: a rotor having a plurality of magnets; a stator provided so as to form an air gap together with the rotor; the first-type three-phase coil is arranged on the stator and consists of a plurality of first-type coils; the second-type three-phase coil is composed of a plurality of second-type coils, and the number of turns wound by each second-type coil is smaller than the number of turns of each of the plurality of first-type coils; a first inverter configured to drive the first type of three-phase coil; and a second inverter configured to drive a second type of three-phase coil while its maximum output is greater than the maximum output of the first inverter.

Description

Technical Field

[0001] The present invention relates to a structure of a motor for driving a vehicle. Background Art

[0002] A hybrid vehicle, an electric vehicle, or the like generates a driving force required to drive the vehicle by operating a motor using electric power supplied from a battery equipped in the vehicle.

[0003] The electric motors used in the above-mentioned vehicles should have high efficiency to reduce the amount of electricity required and improve the output performance of the vehicle.

[0004] The above subject matter disclosed in this section is only for enhancing the understanding of the general background of the present invention. The above content should not be regarded as admitting or suggesting in any form that the subject matter forms the related technology known to ordinary technicians in the field. Summary of the invention

[0005] Therefore, the present invention is made in view of the above problems. An object of the present invention is to provide a six-phase motor that can reduce iron loss and weak magnetic control loss according to the operating point compared with a conventional motor. This improves the efficiency of the motor and increases the maximum output of the motor to achieve enhanced output performance of the vehicle. Enhanced power economy is also achieved, that is, the power consumption of the vehicle is reduced.

[0006] Those skilled in the art to which the present invention pertains should understand that the technical problems to be solved by the present invention are not limited to the above-mentioned technical problems, and other technical problems can be more clearly understood from the following description.

[0007] According to the present invention, the above and other purposes can be achieved by providing a six-phase motor. The six-phase motor includes: a rotor having a plurality of magnets; and a stator configured to form an air gap together with the rotor. The six-phase motor also includes: a first type three-phase coil, which is arranged on the stator and consists of a plurality of first type coils; and a second type three-phase coil, which consists of a plurality of second type coils, and the number of turns of each second type coil is less than the number of turns of each first type coil. The six-phase motor also includes: a first inverter configured to drive the first type three-phase coil; and a second inverter configured to drive the second type three-phase coil, while its maximum output is greater than the maximum output of the first inverter.

[0008] The number of turns of the first type coil is twice the number of turns of the second type coil.

[0009] The maximum output of the second inverter is greater than the maximum output of the first inverter by more than 10%.

[0010] The first type coil and the second type coil are respectively inserted into corresponding slots of the stator.

[0011] The first type of three-phase coil is composed of an A-phase coil, a B-phase coil and a C-phase coil. The second type of three-phase coil is composed of an X-phase coil, a Y-phase coil and a Z-phase coil. The A-phase coil, the B-phase coil and the C-phase coil are arranged in sequence along the circumferential direction of the stator. The X-phase coil, the Y-phase coil and the Z-phase coil are arranged in sequence along the arrangement direction of the A-phase coil, the B-phase coil and the C-phase coil.

[0012] The A-phase coil, B-phase coil, C-phase coil, X-phase coil, Y-phase coil and Z-phase coil are arranged so that A-phase, X-phase, B-phase, Y-phase, C-phase and Z-phase are repeatedly formed in sequence along the circumferential direction of the stator.

[0013] The X-phase coil is inserted into the slot into which the A-phase coil has been inserted and into the slot into which the B-phase coil has been inserted. The Y-phase coil is inserted into another slot into which the B-phase coil has been inserted and into the slot into which the C-phase coil has been inserted. The Z-phase coil is inserted into another slot into which the C-phase coil has been inserted and into another slot into which the A-phase coil has been inserted.

[0014] The A-phase coil is inserted into the i-th slot and the i+1-th slot adjacent to each other of the stator. The B-phase coil is inserted into the i+2-th slot and the i+3-th slot of the stator. The C-phase coil is inserted into the i+4-th slot and the i+5-th slot of the stator. The X-phase coil is inserted into the i+1-th slot and the i+2-th slot of the stator. The Y-phase coil is inserted into the i+3-th slot and the i+4-th slot of the stator. The Z-phase coil is inserted into the i+5-th slot and the i-th slot of the stator.

[0015] Each of the A-phase coil, the B-phase coil, the C-phase coil, the X-phase coil, the Y-phase coil, and the Z-phase coil is continuously inserted into adjacent slots whose number corresponds to a multiple of two.

[0016] The A-phase coil, the B-phase coil and the C-phase coil are inserted into the slot portions corresponding to the radial outer portion of the stator. The X-phase coil, the Y-phase coil and the Z-phase coil are inserted into the slot portions corresponding to the radial inner portion of the stator.

[0017] The first type coil and the second type coil are respectively composed of windings having different thicknesses.

[0018] The first type coil and the second type coil are configured to be alternately inserted into a plurality of slots provided in a circumferential direction of the stator.

[0019] The first type of coil is composed of an A-phase coil, a B-phase coil and a C-phase coil. The second type of coil is composed of an X-phase coil, a Y-phase coil and a Z-phase coil. The A-phase coil, the X-phase coil, the B-phase coil, the Y-phase coil, the C-phase coil and the Z-phase coil are sequentially arranged in a plurality of slots arranged along the circumferential direction of the stator. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] The above and other objects, features and other advantages of the present invention will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings, in which:

[0021] Figure 1 is a circuit diagram of a six-phase motor according to the present invention;

[0022] Figure 2 is a view of one embodiment of a six-phase electric machine according to the present invention, showing sectors of the rotor and stator;

[0023] Figure 3 Is set in Figure 2 Schematic diagram of the six-phase coils at the stator;

[0024] Figure 4 is a view of another embodiment of a six-phase motor according to the present invention;

[0025] Figure 5 is a graph showing the output of the motor according to the present invention and for explaining an example in which a first portion of the motor composed of a first type three-phase coil and a second portion of the motor composed of a second type three-phase coil are controlled to have the same maximum torque; and

[0026] Figure 6 is shown with different number of turns for Figure 5 A graph comparing outputs of six-phase motors for comparison and for explaining an example in which maximum currents respectively applied to a first motor portion consisting of a first type three-phase coil and a second motor portion consisting of a second type three-phase coil are controlled to be equal. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention are described in detail with reference to the accompanying drawings. Throughout the accompanying drawings, the same or similar elements are denoted by the same reference numerals, and redundant descriptions thereof are omitted.

[0028] The suffixes “module” and “unit” of the elements herein are for convenience of description and thus may be used interchangeably without having any distinguishable meanings or functions.

[0029] In the following description of the embodiments of the present invention, the detailed description of the known functions and structures incorporated herein that may have blurred the subject matter of the embodiments of the present invention is omitted. In addition, the embodiments of the present invention should be more clearly understood from the accompanying drawings and should not be limited by the accompanying drawings. It should be understood that all changes, equivalents and substitutes that do not depart from the spirit and technical scope of the present invention are included in the present invention.

[0030] It should be understood that although the terms “first”, “second”, etc. may be used herein to describe various elements, these elements should not be limited by these terms. These terms are only used to distinguish one element from another.

[0031] When an element is described as being "connected" or "linked" to another element, it should be understood that the element can be directly connected or linked to another element, or another element can exist between the two. Conversely, when an element is described as being "directly connected" or "directly coupled" to another element, it should be understood that there are no other elements between them.

[0032] Unless otherwise clearly used, singular expressions include plural meanings. When a component, device, element, etc. of the present invention is described as having a purpose or performing an operation, function, etc., the component, device or element should be considered herein as "configured to" meet the purpose or perform the operation or function.

[0033] In this specification, the terms "include", "comprises", etc. and their variations are intended to express the presence of a characteristic, number, step, operation, element, component or a combination thereof. These terms do not exclude another characteristic, number, step, operation, element, component or any combination thereof, or any addition thereof.

[0034] refer to Figure 1-5 , showing a six-phase motor according to one embodiment of the present invention. The six-phase motor according to each embodiment of the present invention is constructed by including a rotor 3 having a plurality of magnets 1. The motor also includes a stator 7, which is arranged to form an air gap 5 together with the rotor 3. The motor also includes a first type three-phase coil arranged at the stator 7 and composed of a plurality of first type coils 9, and a second type three-phase coil composed of a plurality of second type coils 11, each of the second type coils 11 being wound with a number of turns less than the number of turns of each first type coil 9. The motor also includes: a first inverter 13, configured to drive the first type three-phase coil; and a second inverter 15, configured to drive the second type three-phase coil, while its maximum output is greater than the maximum output of the first inverter 13.

[0035] For example, the number of turns of the first type coil 9 may be twice the number of turns of the second type coil 11 .

[0036] In other words, when the number of turns of the first type coil 9 is 8, the number of turns of the second type coil 11 is 4.

[0037] In this example, the maximum output of the second inverter 15 is greater than the maximum output of the first inverter 13 by more than 10%.

[0038] It can be considered that the first type three-phase coil and the rotor 3 together constitute a first part of the motor, while the second type three-phase coil and the rotor 3 together constitute a second part of the motor.

[0039] In other words, when current is applied only to the first type three-phase coil, the six-phase motor of the present invention can be used as a first part of the motor. In addition, when current is applied only to the second type three-phase coil, the six-phase motor of the present invention can be used as a second part of the motor. On the other hand, when current is applied to the first type three-phase coil and the second type three-phase coil, the six-phase motor of the present invention can be used as a six-phase motor.

[0040] Accordingly, the first inverter 13 drives the first motor, and the second inverter 15 drives the second motor. When the second inverter 15 drives the second motor, the second motor can be controlled to have a maximum output greater than 10% of the maximum output of the first inverter 13.

[0041] When the above-mentioned six-phase motor of the present invention having different numbers of turns is driven to operate as a six-phase motor, there is an advantage in that the maximum torque output from the motor can be maximized when the second part motor having a smaller number of turns is driven by an inverter output higher than the inverter output of the first part motor having a larger number of turns.

[0042] In other words, in a six-phase motor with the same construction of first type three-phase coils and second type three-phase coils, when the first inverter 13 and the second inverter 15 are configured to produce the same maximum output, the maximum torque that can be output from the motor is no higher than the maximum torque of the motor of the present invention.

[0043] When comparing the above relationships through detailed examples, the comparison results can be expressed by the following table:

[0044] Table 1

[0045]

[0046] The conventional six-phase motor is represented in Table 1 as being divided into a first motor section and a second motor section. In order to compare the conventional motor with the present invention, it is not necessary to roughly divide the conventional six-phase motor into the first motor section and the second motor section. This is because the three-phase coil constituting the first motor section and the three-phase motor constituting the second motor section both have six turns (i.e., have the same number of turns). Similarly, the first inverter and the second inverter have the same specifications and therefore produce the same maximum output.

[0047] The six-phase motor with different numbers of turns on the far right of Table 1 is configured according to the present invention. In this motor, the output of its first inverter is less than the output of the second inverter, and the maximum torque of the first part of the motor and the maximum torque of the second part of the motor are both 250Nm (i.e., equal). The six-phase motor with different numbers of turns in the middle of Table 1, and the output of its first inverter and the output of its second inverter are equal, is also shown in Table 1 for comparison with the six-phase motor of the present invention. This six-phase motor is called "comparative six-phase motor with different numbers of turns".

[0048] at the same time, Figure 5 It is shown that a first portion of the motor composed of a first type three-phase coil and a second portion of the motor composed of a second type three-phase coil are controlled to have the same motor output of maximum torque of 250 Nm. Figure 5 is a graph showing motor output.

[0049] exist Figure 5 In the figure, the output of a conventional six-phase motor is represented by "OLD6", the output of the first part of the motor is represented by "M1", the output of the second part of the motor is represented by "M2", and the output in which the maximum torques of the first part of the motor and the second part of the motor are controlled to be equal (i.e., 250Nm) is represented by "MAX".

[0050] also, Figure 6 Shown with different number of turns, for Figure 5 Compare the output of the six-phase motor. Figure 6 is a graph showing an example in which the maximum currents (maximum phase currents) respectively applied to the first and second partial motors are controlled to be equal (ie, to be 500 Arm).

[0051] and Figure 5 Similar, in Figure 6 In the figure, the output of a conventional six-phase motor is represented by "OLD6", the output of the first part of the motor is represented by "M1", the output of the second part of the motor is represented by "M2", and the maximum phase currents applied to the first part of the motor and the second part of the motor, respectively, are controlled to be equal (i.e., 500Arm), represented by "SUM".

[0052] In other words, according to Table 1 and Figure 5 and 6 As shown in the comparison result, it can be seen that when the maximum output of the first motor and the maximum output of the second motor are controlled to be equal according to the present invention, the output MAX forms a higher torque in the high-speed range. This is compared with the output SUM in which the maximum currents of the first motor and the second motor respectively applied to the comparison six-phase motor having different numbers of turns are controlled to be equal.

[0053] Therefore, according to the present invention, a higher maximum motor output can be obtained in a high rotation speed (RPM) range, and thus enhanced driving power performance of the vehicle can be achieved.

[0054] exist Figure 2 In the illustrated first embodiment, the three-phase coils are configured to be inserted into the slots S of the stator 7. In addition, the first type coils 9 and the second type coils 11 are both inserted into the corresponding slots S, respectively.

[0055] In this example, the first type of three-phase coil is composed of an A-phase coil AP, a B-phase coil BP, and a C-phase coil CP. The second type of three-phase coil is composed of an X-phase coil XP, a Y-phase coil YP, and a Z-phase coil ZP. The A-phase coil AP, the B-phase coil BP, and the C-phase coil CP are arranged in sequence along the circumferential direction of the stator 7. The X-phase coil SP, the Y-phase coil YP, and the Z-phase coil ZP are arranged in sequence in the arrangement direction of the A-phase coil AP, the B-phase coil BP, and the C-phase coil CP.

[0056] The X-phase coil XP is inserted into the slot into which the A-phase coil AP has been inserted, and is inserted into the slot into which the B-phase coil BP has been inserted. The Y-phase coil YP is inserted into another slot into which the B-phase coil BP has been inserted, and is inserted into the slot into which the C-phase coil CP has been inserted. The Z-phase coil ZP is inserted into another slot into which the C-phase coil CP has been inserted, and is inserted into another slot into which the A-phase coil AP has been inserted.

[0057] For example, in the present embodiment, the A-phase coil AP is inserted into the i-th slot S_i and the i+1-th slot S_i+1 adjacent to each other of the stator 7. The B-phase coil BP is inserted into the i+2-th slot S_i+2 and the i+3-th slot S_i+3 of the stator 7. The C-phase coil CP is inserted into the i+4-th slot S_i+4 and the i+5-th slot S_i+5 of the stator 7. The X-phase coil XP is inserted into the i+1-th slot S_i+1 and the i+2-th slot S_i+2 of the stator 7. The Y-phase coil YP is inserted into the i+3-th slot S_i+3 and the i+4-th slot S_i+4 of the stator 7. The Z-phase coil ZP is inserted into the i+5-th slot S_i+5 and the i-th slot S_i of the stator 7.

[0058] Accordingly, the A-phase coil AP, the B-phase coil BP, the C-phase coil CP, the X-phase coil XP, the Y-phase coil YP and the Z-phase coil ZP are arranged so that the A-phase, X-phase, B-phase, Y-phase, C-phase and Z-phase are formed sequentially and repeatedly in the circumferential direction of the stator 7.

[0059] exist Figure 2In the illustrated embodiment, each of the A-phase coil AP, the B-phase coil BP, the C-phase coil CP, the X-phase coil XP, the Y-phase coil YP, and the Z-phase coil ZP has a structure that is continuously inserted into two adjacent slots. Each of the A-phase coil AP, the B-phase coil BP, the C-phase coil CP, the X-phase coil XP, the Y-phase coil YP, and the Z-phase coil ZP may have a structure that is continuously inserted into adjacent slots according to the size and structure of the motor to be constructed, and the number of adjacent slots corresponds to a multiple of 2, such as 4, 6, etc.

[0060] In other words, for example, the coils may be arranged in such a manner that when the A-phase coil AP is continuously inserted into the first to fourth slots, the B-phase coil BP is continuously inserted into the fifth to eighth slots, and the X-phase coil XP is continuously inserted into the third to sixth slots.

[0061] The A-phase coil AP, the B-phase coil BP and the C-phase coil CP are inserted into the portions of the slots corresponding to the outer portion in the radial direction of the stator 7. On the other hand, the X-phase coil XP, the Y-phase coil YP and the Z-phase coil ZP are inserted into the portions of the slots corresponding to the inner portion in the radial direction of the stator 7.

[0062] Accordingly, compared with the magnetic field formed by the A-phase coil AP, the B-phase coil BP and the C-phase coil CP, the magnetic field formed by the X-phase coil XP, the Y-phase coil YP and the Z-phase coil ZP having fewer turns is set closer to the rotor 3 so that it can function more effectively.

[0063] The first type coil 9 and the second type coil 11 may be respectively formed of windings having different thicknesses.

[0064] In other words, the first type coil 9 and the second type coil 11 may be configured to have windings having different thicknesses and different numbers of turns, respectively.

[0065] At the same time, Figure 4 In the illustrated second embodiment, the first type coils 9 and the second type coils 11 are configured to be alternately inserted into a plurality of slots S provided in the circumferential direction of the stator 7 .

[0066] In other words, the first type coil 9 is composed of an A-phase coil AP, a B-phase coil BP, and a C-phase coil CP. The second type coil 11 is composed of an X-phase coil XP, a Y-phase coil YP, and a Z-phase coil ZP. The A-phase coil AP, the X-phase coil XP, the B-phase coil BP, the Y-phase coil YP, the C-phase coil CP, and the Z-phase coil ZP are sequentially arranged in a plurality of slots S arranged along the circumferential direction of the stator 7.

[0067] The above configuration constitutes a hairpin motor. For example, it can be seen that each of the A-phase coil AP, the B-phase coil BP, and the C-phase coil CP is inserted into each slot S for 8 turns. In addition, each of the X-phase coil XP, the Y-phase coil YP, and the Z-phase coil ZP is inserted into each slot S for 6 turns.

[0068] Meanwhile, the above-mentioned motor of the present invention may perform a three-phase operation in which only the first part of the motor is driven, or may also perform a three-phase operation in which only the second part of the motor is driven.

[0069] The three-phase operation of driving only the first part of the motor can be used in the RPM range where the motor runs at a relatively low speed. In this example, the required current can be reduced, thereby reducing copper losses. This can be compared with the example of driving a conventional six-phase motor at the same operating point as the motor of the present invention. Therefore, relatively excellent efficiency can be obtained.

[0070] In other words, the number of turns of the first type coil 9 constituting the first partial motor is greater than the number of turns of each phase coil constituting a conventional six-phase motor of the same size as the motor of the present invention, and thus the required current can be reduced. Thus, compared with an example of driving a conventional six-phase motor at the same operating point as the motor of the present invention, a reduction in copper loss can be achieved.

[0071] In addition, the three-phase operation of driving only the second part of the motor can be used in the RPM range where the motor runs at a relatively high speed. In this example, compared with the example of driving a conventional six-phase motor at the same operating point as the motor of the present invention, the back electromotive force can be reduced, thereby reducing the weak field control loss. Therefore, relatively excellent efficiency can be obtained.

[0072] In other words, the number of turns of the second type coil 11 constituting the second partial motor is smaller than the number of turns of each phase coil constituting a conventional six-phase motor of the same size as the motor of the present invention, and thus the back electromotive force can be reduced. Thus, the field weakening control loss is reduced compared to the case where the conventional six-phase motor is driven at the same operating point as the motor of the present invention.

[0073] For reference, "a conventional six-phase motor having the same size" may be interpreted as a motor having a number of turns per phase corresponding to the average number of turns of the first type coil 9 in the first part of the motor and the number of turns of the second type coil 11 in the second part of the motor.

[0074] As is apparent from the above description, according to the motor of the present invention, compared with the conventional motor, the iron loss and the field weakening control loss can be reduced according to the operating point, thereby achieving the improvement of the efficiency of the motor and the increase of the maximum output of the motor. Therefore, the enhanced output performance of the vehicle to which the motor is applied can be achieved, while achieving the enhancement of the power economy of the vehicle.

[0075] Although the embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, without departing from the scope and spirit of the invention as disclosed in the accompanying claims.

Claims

1. A six-phase motor, comprising: a rotor having a plurality of magnets; a stator, arranged to form an air gap together with the rotor; A first type three-phase coil, arranged on the stator and composed of a plurality of first type coils; A second type three-phase coil, composed of a plurality of second type coils, each of which is wound with a smaller number of turns than each of the plurality of first type coils; a first inverter configured to drive the first type three-phase coil; as well as The second inverter is configured to drive the second type three-phase coil, and the maximum output thereof is greater than the maximum output of the first inverter.

2. The six-phase motor according to claim 1, wherein: The number of turns of the plurality of first type coils is twice the number of turns of the plurality of second type coils.

3. The six-phase motor according to claim 1, wherein: The maximum output of the second inverter is greater than the maximum output of the first inverter by more than 10%.

4. The six-phase motor according to claim 1, wherein: The plurality of first type coils and the plurality of second type coils are respectively inserted into corresponding slots of the stator.

5. The six-phase motor according to claim 4, wherein: The first type of three-phase coil is composed of an A-phase coil, a B-phase coil and a C-phase coil; The second type of three-phase coil is composed of an X-phase coil, a Y-phase coil and a Z-phase coil; The A-phase coil, the B-phase coil and the C-phase coil are sequentially arranged along the circumferential direction of the stator; and The X-phase coil, the Y-phase coil, and the Z-phase coil are sequentially arranged along an arrangement direction of the A-phase coil, the B-phase coil, and the C-phase coil.

6. The six-phase motor according to claim 5, wherein: The A-phase coil, the B-phase coil, the C-phase coil, the X-phase coil, the Y-phase coil, and the Z-phase coil are arranged so that the A-phase, X-phase, B-phase, Y-phase, C-phase, and Z-phase are sequentially and repeatedly formed along the circumferential direction of the stator.

7. The six-phase motor according to claim 6, wherein: The X-phase coil is inserted into the slot into which the A-phase coil has been inserted and into the slot into which the B-phase coil has been inserted; The Y-phase coil is inserted into another slot into which the B-phase coil has been inserted and into the slot into which the C-phase coil has been inserted; and The Z-phase coil is inserted into the other slot into which the C-phase coil has been inserted and into the other slot into which the A-phase coil has been inserted.

8. The six-phase motor according to claim 7, wherein: The A-phase coil is inserted into the i-th slot and the i+1-th slot adjacent to each other of the stator; The B-phase coil is inserted into the i+2th slot and the i+3th slot of the stator; The C-phase coil is inserted into the i+4th slot and the i+5th slot of the stator; The X-phase coil is inserted into the i+1th slot and the i+2th slot of the stator; The Y-phase coil is inserted into the i+3th slot and the i+4th slot of the stator; and The Z-phase coil is inserted into the (i+5)th slot and the (i)th slot of the stator.

9. The six-phase motor according to claim 7, wherein: Each of the A-phase coil, the B-phase coil, the C-phase coil, the X-phase coil, the Y-phase coil, and the Z-phase coil is continuously inserted into adjacent slots whose number corresponds to a multiple of two.

10. The six-phase motor according to claim 7, wherein: The A-phase coil, the B-phase coil, and the C-phase coil are inserted into portions of slots corresponding to the outer sides in the radial direction of the stator; and The X-phase coil, the Y-phase coil, and the Z-phase coil are inserted into portions of slots corresponding to the inside in the radial direction of the stator.

11. The six-phase motor according to claim 1, wherein: The plurality of first type coils and the plurality of second type coils are respectively constituted of windings having different thicknesses.

12. The six-phase motor according to claim 1, wherein: The plurality of first type coils and the plurality of second type coils are configured to be alternately inserted into a plurality of slots provided in a circumferential direction of the stator.

13. The six-phase electric machine according to claim 12, wherein: The plurality of first type coils are composed of an A-phase coil, a B-phase coil and a C-phase coil; The plurality of second type coils are composed of an X-phase coil, a Y-phase coil and a Z-phase coil; and The A-phase coil, the X-phase coil, the B-phase coil, the Y-phase coil, the C-phase coil, and the Z-phase coil are sequentially disposed in a plurality of slots disposed along a circumferential direction of the stator.

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