Motor control method

Abstract

The present invention relates to a motor control method that performs control such that a phase angle of a first-part motor including a first-type three-phase winding is the same as a phase angle of a second-part motor including a second-type three-phase winding in a rotational speed region lower than a reference rotational speed, and performs control such that a phase angle of the second-part motor is the same as a phase angle of the first-type three-phase winding in a rotational speed region greater than the reference rotational speed. Control is performed such that phase angles of the first part motor and the second part motor are different.

Description

Technical Field

[0001] The present invention relates to a method for controlling a six-phase motor that can be used for vehicle drive. Background Art

[0002] Hybrid electric vehicles, electric vehicles, etc. use electric power provided by a battery mounted on the vehicle to drive an electric motor, thereby generating the driving force required for vehicle travel.

[0003] The electric motor for vehicles as described above needs to be made more efficient to meet the vehicle's power consumption per 100 kilometers and output performance.

[0004] The content described as the above background art is only used to enhance the understanding of the background of the present invention and should not be regarded as admitting that it belongs to the prior art known to those skilled in the art of this technology.

[0005] [Prior Art Documents]

[0006] Patent Document 1: WO2022 - 045400

[0007] Patent Document 2: WO2018 - 142635 Summary of the Invention

[0008] An object of the present invention is to provide a motor control method that enables more effective control of a six-phase motor in which the number of series turns per phase of three-phase windings is configured differently from the number of series turns per phase of the remaining three-phase windings, so that the power performance required for the vehicle can be provided more effectively.

[0009] The motor control method of the present invention aiming to achieve the above object controls a six-phase motor configured such that the maximum current applied to a first part of the motor is the same as the maximum current applied to a second part of the motor. The first part of the motor includes three-phase windings of a first type, and the second part of the motor includes three-phase windings of a second type in which the number of series turns per phase is less than that of the three-phase windings of the first type.

[0010] In a region where the required torque of the six-phase motor is below a predetermined reference torque, control is executed such that the output torque of the first part of the motor including the three-phase windings of the first type is the same as the output torque of the second part of the motor including the three-phase windings of the second type.

[0011] In a region where the required torque of the six-phase motor is greater than the reference torque, control is executed such that the output torque of the first part of the motor is different from the output torque of the second part of the motor.

[0012] The reference torque can be set to a torque corresponding to twice the maximum torque of the second part of the motor.

[0013] In a region where the required torque of the six-phase motor is greater than the reference torque, control is performed such that the output torque of the first part of the motor is different from the output torque of the second part of the motor according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

[0014] In a speed region below a predetermined reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are the same.

[0015] In a speed region greater than the reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are different.

[0016] The reference speed is set to the base speed of the first part of the motor.

[0017] The operating region where only the second part of the motor is driven is set in a speed region higher than the operating region where only the first part of the motor is driven.

[0018] The first part of the motor includes the first type of three-phase windings arranged at equal intervals in the circumferential direction around the rotation axis of the six-phase motor.

[0019] The second part of the motor includes the second type of three-phase windings arranged at equal intervals in the circumferential direction around the rotation axis of the six-phase motor.

[0020] The first type of three-phase windings includes an A-phase winding, a B-phase winding, and a C-phase winding.

[0021] The second type of three-phase windings includes an X-phase winding, a Y-phase winding, and a Z-phase winding.

[0022] The A-phase winding, B-phase winding, and C-phase winding are arranged in sequence in the circumferential direction of the stator.

[0023] The X-phase winding, Y-phase winding, and Z-phase winding are arranged in sequence in the direction in which the A-phase winding, B-phase winding, and C-phase winding are arranged.

[0024] The A-phase winding, B-phase winding, C-phase winding, X-phase winding, Y-phase winding, and Z-phase winding are arranged such that the A-phase, X-phase, B-phase, Y-phase, C-phase, and Z-phase are repeatedly formed in sequence in the circumferential direction of the stator.

[0025] The first type of three-phase windings and the second type of three-phase windings are formed by windings with different thicknesses.

[0026] The number of turns of the first type of three-phase windings is more than 10% more than the number of turns of the second type of three-phase windings.

[0027] In addition, the motor control method of the present invention for achieving the above object controls a six-phase motor configured such that the maximum current applied to the first part of the motor is the same as the maximum current applied to the second part of the motor. The first part of the motor includes a first type of three-phase winding, and the second part of the motor includes a second type of three-phase winding with a smaller number of turns in series per phase than the first type of three-phase winding.

[0028] In a speed region below a predetermined reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are the same.

[0029] In a speed region greater than the reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are different.

[0030] The reference speed is set to the base speed of the first part of the motor.

[0031] The operating region for driving only the second part of the motor is set in a speed region higher than the operating region for driving only the first part of the motor.

[0032] In a region where the required torque of the six-phase motor is below the torque corresponding to twice the maximum torque of the second part of the motor, control is performed such that the output torques of the first part of the motor and the second part of the motor are the same.

[0033] In a region greater than twice the maximum torque of the second part of the motor, control is performed such that the output torques of the first part of the motor and the second part of the motor are different according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

[0034] In addition, the motor control method of the present invention for achieving the above object controls a six-phase motor configured such that the maximum current applied to the first part of the motor is the same as the maximum current applied to the second part of the motor. The first part of the motor includes a first type of three-phase winding, and the second part of the motor includes a second type of three-phase winding with a smaller number of turns in series per phase than the first type of three-phase winding.

[0035] According to a predetermined reference speed and reference torque, the six-phase operation region of operating the six-phase motor in six phases is divided into four operating regions.

[0036] In the six-phase first operating region among the four operating regions, control is performed such that both the phase angle and torque of the first part of the motor and the second part of the motor are the same. The six-phase first operating region is a region where the speed is below the reference speed and the torque is below the reference torque.

[0037] In the six-phase second operating region among the four operating regions, control is executed such that the phase angles of the first part of the motor and the second part of the motor are different but the torques are the same. The six-phase second operating region is a region where the rotational speed is greater than the reference rotational speed and the torque is below the reference torque.

[0038] In the six-phase third operating region among the four operating regions, control is executed such that the phase angles of the first part of the motor and the second part of the motor are the same but the torques are different. The six-phase third operating region is a region where the rotational speed is below the reference rotational speed and the torque is greater than the reference torque.

[0039] In the six-phase fourth operating region among the four operating regions, control is executed such that both the phase angles and torques of the first part of the motor and the second part of the motor remain different. The six-phase fourth operating region is a region where the rotational speed is greater than the reference rotational speed and the torque is greater than the reference torque.

[0040] The reference rotational speed for dividing the four operating regions is set to the base rotational speed of the first part of the motor, and the reference torque is set to twice the maximum torque of the second part of the motor.

[0041] The three-phase second operating region for driving only the second part of the motor is set in a rotational speed region higher than the three-phase first operating region for driving only the first part of the motor.

[0042] The three-phase first operating region and the three-phase second operating region are set to overlap within the six-phase first operating region and the six-phase second operating region.

[0043] When control is executed such that the torques of the first part of the motor and the second part of the motor are different from each other, the output torque of the first part of the motor is made different from the output torque of the second part of the motor according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

[0044] The present invention can more effectively provide the power performance required for a vehicle by more effectively controlling a six-phase motor configured such that the number of series turns per phase of three-phase windings is different from the number of series turns per phase of the remaining three-phase windings. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 A diagram for describing the structure of a six-phase motor with different winding types to which the present invention can be applied.

[0046] Figure 2 Conceptually showing Figure 1 A diagram of the six-phase windings arranged in the stator.

[0047] Figure 3 Exemplarily showing a drive circuit for driving Figure 1 The six-phase motor.

[0048] Figure 4 A graph showing the maximum power lines of the first part of the heterogeneous-wound six-phase motor to which the present invention can be applied, the maximum power line of the second part of the motor, and the maximum total power line representing the sum thereof.

[0049] Figure 5 For Figure 4 a graph showing the operating region of the six-phase motor of the present invention.

[0050] Description of Reference Numerals

[0051] 1: Permanent magnet

[0052] 3: Rotor

[0053] 5: Air gap

[0054] 7: Stator

[0055] 13: Inverter

[0056] M1: First part of the motor

[0057] M2: Second part of the motor

[0058] BR: Reference speed

[0059] 6P-1: First six-phase operating region

[0060] 6P-2: Second six-phase operating region

[0061] 6P-3: Third six-phase operating region

[0062] 6P-4: Fourth six-phase operating region

[0063] 3P-2: Second three-phase operating region

[0064] 3P-1: First three-phase operating region. Detailed Description of the Invention

[0065] Hereinafter, embodiments disclosed in the present specification will be described in detail with reference to the accompanying drawings. It should be noted that when assigning reference numerals to the components in the respective drawings, for the same components, even if they are shown in different drawings, the same reference numerals are used as much as possible, and the repeated description thereof is omitted.

[0066] In the following description, the component suffixes "module" and "section" are given or mixed only for the convenience of writing, and they do not have specific meanings or functions for mutual distinction.

[0067] When describing the embodiments disclosed in this specification, if it is considered that the specific description of related well-known technologies may confuse the core content of the embodiments disclosed in this specification, the detailed description of such well-known technologies will be omitted. In addition, the drawings are only used to more intuitively understand the embodiments disclosed in this specification, and their content does not limit the technical ideas involved in this specification. It should be understood that the present invention covers all variant embodiments, equivalent embodiments, and alternative embodiments included within the spirit and scope of the present invention.

[0068] In the specification, ordinal terms such as "first", "second", etc. may be used to describe different components, but these components are not restricted by the above terms. These terms are only used to distinguish one component from another.

[0069] When describing that a certain component is "connected" or "connected in series" to another component, it should be understood that such connection or connection in series can be direct or can be achieved indirectly through other components. On the contrary, when describing that a certain component is "directly connected" or "directly connected in series" to another component, it means that there are no other components in between.

[0070] Unless the context clearly indicates otherwise, singular forms of expressions should be understood to include plural forms as well.

[0071] In this specification, the terms "comprising" or "having" should be understood to mean that there exist the features, values, steps, actions, components, parts, or combinations thereof described in the specification, but do not exclude the possibility of further including one or more other features, values, steps, actions, components, parts, or combinations thereof.

[0072] Refer to Figures 1 to 3 , and describe the structure of a six-phase motor with dissimilar windings applicable to the motor control method of the present invention.

[0073] Refer to Figure 1 , a rotor 3 including a permanent magnet 1 is disposed at the center of the six-phase motor, and a stator 7 is provided in such a way as to form an air gap 5 with the rotor 3 and surround the periphery of the rotor 3. A first type of three-phase winding 9 and a second type of three-phase winding 11 are disposed on the stator 7.

[0074] For reference, Figure 1 shows a partial sector section of the six-phase motor. Actually, the configuration centered on the rotor 3 (the configuration shown in the figure) forms a complete circle, thereby forming a six-phase motor.

[0075] Among them, the second type of three-phase winding 11 has a smaller number of turns in series per phase than the first type of three-phase winding 9.

[0076] That is, for example, when the first type of three-phase winding 9 is composed of a phase winding AP, a B phase winding BP, and a C phase winding CP, and the second type of three-phase winding 11 is composed of an X phase winding XP, a Y phase winding YP, and a Z phase winding ZP, the A phase winding AP, the B phase winding BP, and the C phase winding CP of the first type of three-phase winding 9 are respectively wound 8 turns, and the X phase winding XP, the Y phase winding YP, and the Z phase winding ZP of the second type of three-phase winding 11 are respectively wound 4 turns.

[0077] Preferably, the number of turns of the first type of three-phase winding 9 is at least 10% more than that of the second type of three-phase winding 11, so that the number of series turns per phase also forms more than 10%.

[0078] The A phase winding AP, the B phase winding BP, and the C phase winding CP are arranged in sequence along the circumferential direction of the stator 7, and the X phase winding XP, the Y phase winding YP, and the Z phase winding ZP are arranged in sequence along the direction in which the A phase winding AP, the B phase winding BP, and the C phase winding CP are arranged.

[0079] The first type of three-phase winding 9 arranged at equal intervals along the circumferential direction with the rotation axis of the six-phase motor as the center can be regarded as forming a first part of the motor M1 together with the rotor 3, and the second type of three-phase winding 11 arranged at equal intervals along the circumferential direction with the rotation axis of the six-phase motor as the center can be regarded as forming a second part of the motor M2 together with the rotor 3.

[0080] That is, the six-phase motor of the present invention can be regarded as being composed of the first part of the motor M1 and the second part of the motor M2. In fact, only current is applied to the first type of three-phase winding 9 that constitutes the first part of the motor M1, and it can also be driven as a three-phase motor. Only current is applied to the second type of three-phase winding 11 that constitutes the second part of the motor M2, and it can also be driven as a three-phase motor.

[0081] The A phase winding AP, the B phase winding BP, the C phase winding CP, the X phase winding XP, the Y phase winding YP, and the Z phase winding ZP are as Figure 2 shown, and can be configured to repeatedly form the A phase, the X phase, the B phase, the Y phase, the C phase, and the Z phase in sequence along the circumferential direction of the stator 7.

[0082] On the other hand, the first type of three-phase winding 9 and the second type of three-phase winding 11 can be formed by winding wires with different thicknesses.

[0083] In addition, the six-phase motor composed of the first type of three-phase winding 9 and the second type of three-phase winding 11 as described above can form a drive circuit as Figure 3 shown.

[0084] In Figure 3In [the figure], on the right side, the six-phase windings constituting the six-phase motor are shown. Among them, the three on the upper side are the A-phase winding AP, B-phase winding BP, and C-phase winding CP that constitute the first partial motor M1, and the three on the lower side are the X-phase winding XP, Y-phase winding YP, and Z-phase winding ZP that constitute the second partial motor M2. On the left side is an inverter 13 having six branches for driving the six-phase motor.

[0085] By controlling the switching elements arranged on each arm of the inverter 13, the six-phase motor can be driven.

[0086] The present invention is a technique for controlling a six-phase motor. Among them, the maximum currents that can be controlled by the switching elements of the inverter are all the same, so that the maximum current applied to the first partial motor M1 is the same as the maximum current applied to the second partial motor M2. The first partial motor M1 is composed of the first-type three-phase windings 9, and the second partial motor M2 is composed of second-type three-phase windings 11 in which the number of turns in series per phase is less than that of the first-type three-phase windings 9.

[0087] Figure 4 The maximum power line M1_PL of the first partial motor M1, the maximum power line M2_PL of the second partial motor M2, the first maximum total power line SUM_1, and the second maximum total power line SUM_2 of the six-phase motor with different windings applicable to the present invention are shown together.

[0088] Among them, as described later, the first maximum total power line SUM_1 is the maximum total power line when control is executed so that the phase angles of the first partial motor M1 and the second partial motor M2 are the same, and the second maximum total power line SUM_2 is the maximum total power line when control is executed so that the phase angles of the first partial motor M1 and the second partial motor M2 are different from each other.

[0089] As a reference, M3_PL refers to the maximum power line of a conventional ordinary six-phase motor, and the six-phase windings of this ordinary six-phase motor are all wound with the average number of turns of the first-type three-phase windings 9 and the second-type three-phase windings 11.

[0090] Figure 5 For Figure 4 a diagram showing the operating region of the six-phase motor of the present invention on the chart.

[0091] Refer to Figure 4 and Figure 5, in the region where the required torque of the six-phase motor of the present invention is below the predetermined reference torque BT, control is executed such that the output torque of the first partial motor M1 composed of the first type of three-phase winding 9 is the same as the output torque of the second partial motor M2 composed of the second type of three-phase winding 11; in the region where the required torque of the six-phase motor is greater than the reference torque BT, control is executed such that the output torque of the first partial motor M1 is different from the output torque of the second partial motor M2.

[0092] Among them, the reference torque BT can be set to the torque corresponding to twice the maximum torque of the second partial motor M2.

[0093] That is, the present invention executes control such that the output torque of the first partial motor M1 is the same as the output torque of the second partial motor M2 in the operating region corresponding to the torque below twice the maximum torque of the second partial motor M2; in the operating region greater than twice the maximum torque of the second partial motor M2, control is executed such that the output torque of the first partial motor M1 is different from the output torque of the second partial motor M2, where the second partial motor M2 is composed of a second type of three-phase winding 11 with the number of turns in series per phase less than that of the first type of three-phase winding 9.

[0094] If the control is such that the torques of the first partial motor M1 and the second partial motor M2 are the same, compared with the case where the control is different, the Noise Vibration Harshness (NVH) performance is excellent. Therefore, the region where the torques of the first partial motor M1 and the second partial motor M2 are controlled to be the same as much as possible is expanded to the region divided according to the reference torque BT.

[0095] Among them, the so-called execution of control such that the output torques of the first partial motor M1 and the second partial motor M2 are the same means that the output torque of the first partial motor M1 and the output torque of the second partial motor M2 have a 1:1 relationship.

[0096] In addition, in the region where the required torque of the six-phase motor is greater than the reference torque BT, when control is executed such that the output torque of the first partial motor M1 is different from the output torque of the second partial motor M2, control can be performed according to the ratio between the torque constant of the first partial motor M1 and the torque constant of the second partial motor M2.

[0097] For example, when the torque constant of the first partial motor M1 is 2 and the torque constant of the second partial motor M2 is 1, the first partial motor M1 and the second partial motor M2 are controlled such that the motor torque ratio is 2:1.

[0098] For reference, the torque constant is proportional to the number of turns connected in series per phase of the motor.

[0099] On the other hand, in Figure 5 , the six-phase operation region below the reference torque BT is divided into a six-phase first operation region 6P-1 and a six-phase second operation region 6P-2. In these regions, as described above, control is performed so that the torque of the first part of the motor M1 and the torque of the second part of the motor M2 are the same, in order to improve the Noise, Vibration, and Harshness (NVH) performance as much as possible.

[0100] In addition, in Figure 5 , the six-phase operation region greater than the reference torque BT is divided into a six-phase third operation region 6P-3 and a six-phase fourth operation region 6P-4. In these regions, as described above, control is performed so that the torque of the first part of the motor M1 is different from the torque of the second part of the motor M2, in order to satisfy the required torque of the six-phase motor as much as possible.

[0101] For reference, Figure 5 the parts identified with the same hatching in

[0102] On the other hand, in the speed region below the predetermined reference speed, control is performed so that the phase angles of the first part of the motor M1 and the second part of the motor M2 are the same, and in the speed region greater than the reference speed, control is performed so that the phase angles of the first part of the motor M1 and the second part of the motor M2 are different.

[0103] Among them, the reference speed BR can be set to the base speed of the first part of the motor M1.

[0104] That is, with reference to the base speed of the first part of the motor M1 composed of the first type of three-phase winding 9 with a relatively high number of turns, in the speed region below it, control is performed so that the phase angles of the first part of the motor M1 and the second part of the motor M2 are the same, and in the speed region greater than the base speed, control is performed so that the phase angles of the first part of the motor M1 and the second part of the motor M2 are different from each other, so that in the speed region greater than the base speed, the maximum output of the six-phase motor can be increased.

[0105] Refer to Figure 4, the maximum total power line SUM_1 when the execution control makes the phase angles of the first part motor M1 and the second part motor M2 the same is compared with the maximum total power line SUM_2 when the execution control makes the phase angles of the first part motor M1 and the second part motor M2 different. It can be seen that compared with the maximum total power line SUM_1 when the execution control makes the phase angles the same, the maximum total power line SUM_2 when the execution control makes the phase angles different can generate a relatively higher maximum output in the speed region greater than the reference speed BR.

[0106] Therefore, according to the present invention, as described above, in the speed region greater than the reference speed BR, the heterogeneous winding six-phase motor composed of the first part motor M1 and the second part motor M2 is controlled so that the phase angles of the first part motor M1 and the second part motor M2 are different from each other, so that it is easier to provide high output performance in the high-speed operation region required by the vehicle.

[0107] Among them, the so-called execution control makes the phase angles of the first part motor M1 and the second part motor M2 the same or different, which can be understood as the phase of the current flowing through the A-phase winding of the first part motor M1 and the phase of the current flowing through the X-phase winding of the second part motor M2 are the same or different from each other.

[0108] Of course, currents with a 120° phase difference from each other are supplied to the A-phase winding AP, B-phase winding BP, and C-phase winding CP of the first part motor M1; similarly, currents with a 120° phase difference from each other are also supplied between the X-phase winding XP, Y-phase winding YP, and Z-phase winding ZP of the second part motor M2.

[0109] In Figure 5 , based on the reference speed BR, on the left, the six-phase first operation region 6P-1 and the six-phase third operation region 6P-3 where the execution control makes the phase angles of the first part motor M1 and the second part motor M2 the same are shown, and on the right, the six-phase second operation region 6P-2 and the six-phase fourth operation region 6P-4 where the execution control makes the phase angles of the first part motor M1 and the second part motor M2 different are shown.

[0110] On the other hand, as Figure 5 shown, the three-phase second operation region 3P-2 that only drives the second part motor M2 is set in a speed region higher than the three-phase first operation region 3P-1 that only drives the first part motor M1.

[0111] This ultimately enables when using the six-phase motor of the present invention as a three-phase motor, only driving the first part motor M1 in a relatively low speed region to realize the three-phase motor, and only driving the second part motor M2 in a relatively high speed region to realize the three-phase motor.

[0112] As described above, if only the first part of the motor M1 is driven to implement a three-phase motor in the first three-phase operating region 3P-1, which is a relatively low rotational speed region, since the number of turns of the first type of three-phase winding 9 that makes up the first part of the motor M1 is relatively more than the number of turns of the second type of three-phase winding 11 that makes up the second part of the motor M2, therefore, at the same operating point, the required current is reduced, thereby achieving the effect of reducing copper loss.

[0113] In addition, as described above, if only the second part of the motor M2 is driven to implement a three-phase motor in the second three-phase operating region 3P-2, which is a relatively high rotational speed region, then at the same operating point, the back electromotive force is reduced, thereby achieving the effect of reducing field weakening control loss.

[0114] The present invention can also be described as follows.

[0115] That is, the motor control method of the present invention controls a six-phase motor, the six-phase motor is configured such that the maximum current applied to the first part of the motor M1 is the same as the maximum current applied to the second part of the motor M2, the first part of the motor M1 is composed of a first type of three-phase winding, and the second part of the motor M2 is composed of a second type of three-phase winding in which the number of turns in series per phase is less than that of the first type of three-phase winding, wherein the motor control method is as follows:

[0116] In a rotational speed region below a predetermined reference rotational speed BR, control is performed such that the phase angles of the first part of the motor M and the second part of the motor M2 are the same; in a rotational speed region greater than the reference rotational speed BR, control is performed such that the phase angles of the first part of the motor M1 and the second part of the motor M2 are different.

[0117] Wherein, the reference rotational speed BR is set to the base rotational speed of the first part of the motor M1.

[0118] The operating region where only the second part of the motor M2 is driven is set in a rotational speed region higher than the operating region where only the first part of the motor M1 is driven.

[0119] In addition, in a region where the required torque of the six-phase motor is below the torque corresponding to twice the maximum torque of the second part of the motor M2, control is performed such that the output torques of the first part of the motor M1 and the second part of the motor M2 are the same; in a region greater than twice the maximum torque of the second part of the motor M2, control is performed such that the output torques of the first part of the motor M1 and the second part of the motor M2 are different according to the ratio between the torque constant of the first part of the motor M1 and the torque constant of the second part of the motor M2.

[0120] In addition, the present invention can also be described as follows.

[0121] That is, the motor control method of the present invention controls a six-phase motor, which is configured such that the maximum current applied to the first part of the motor M1 is the same as the maximum current applied to the second part of the motor M2. The first part of the motor M1 is composed of a first type of three-phase winding 9, and the second part of the motor M2 is composed of a second type of three-phase winding 11 with the number of turns in series per phase less than that of the first type of three-phase winding. Among them, the motor control method is as follows:

[0122] According to a predetermined reference speed and reference torque, the six-phase operation region for operating the six-phase motor in six-phase is divided into four operation regions;

[0123] In the six-phase first operation region 6P-1 among the four operation regions, control is executed such that both the phase angle and torque of the first part of the motor M1 and the second part of the motor M2 are kept the same. The six-phase first operation region 6P-1 is a region where the speed is below the reference speed and the torque is below the reference torque;

[0124] In the six-phase second operation region 6P-2 among the four operation regions, control is executed such that the phase angles of the first part of the motor M1 and the second part of the motor M2 are different but the torques are the same. The six-phase second operation region 6P-2 is a region where the speed is greater than the reference speed and the torque is below the reference torque;

[0125] In the six-phase third operation region 6P-3 among the four operation regions, control is executed such that the phase angles of the first part of the motor M1 and the second part of the motor M2 are the same but the torques are different. The six-phase third operation region 6P-3 is a region where the speed is below the reference speed and the torque is greater than the reference torque;

[0126] In the six-phase fourth operation region 6P-4 among the four operation regions, control is executed such that both the phase angle and torque of the first part of the motor M1 and the second part of the motor M2 are kept different. The six-phase fourth operation region 6P-4 is a region where the speed is greater than the reference speed and the torque is greater than the reference torque.

[0127] The reference speed BR for dividing the four operation regions is set to the base speed of the first part of the motor, and the reference torque BT is set to twice the maximum torque of the second part of the motor.

[0128] The three-phase second operation region 3P-2 for driving only the second part of the motor M2 is set in a speed region higher than the three-phase first operation region 3P-1 for driving only the first part of the motor M1.

[0129] The three-phase first operating region 3P-1 and the three-phase second operating region 3P-2 are set to overlap within the six-phase first operating region 6P-1 and the six-phase second operating region 6P-2.

[0130] When control is executed such that the torques of the first partial motor M1 and the second partial motor M2 are different from each other, the output torque of the first partial motor M1 and the output torque of the second partial motor M2 are made different according to the ratio between the torque constant of the first partial motor M1 and the torque constant of the second partial motor M2.

[0131] The present invention has been illustrated and described by specific embodiments. However, various improvements and variations can be made to the present invention without departing from the technical idea provided by the claims, which will be obvious to those skilled in the art.

Claims

1. A motor control method, which controls a six-phase motor configured such that the maximum current applied to a first part of the motor is the same as the maximum current applied to a second part of the motor. The first part of the motor includes a first type of three-phase winding, and the second part of the motor includes a second type of three-phase winding with a smaller number of turns in series per phase than the first type of three-phase winding. It is characterized in that, in a region where the required torque of the six-phase motor is below a predetermined reference torque, control is performed such that the output torque of the first part of the motor including the first type of three-phase winding is the same as the output torque of the second part of the motor including the second type of three-phase winding; in a region where the required torque of the six-phase motor is greater than the reference torque, control is performed such that the output torque of the first part of the motor is different from the output torque of the second part of the motor.

2. The motor control method according to claim 1, characterized in that, in a region where the required torque of the six-phase motor is greater than the reference torque, control is performed such that the output torque of the first part of the motor is different from the output torque of the second part of the motor according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

3. The motor control method according to claim 2, characterized in that, the reference torque is set to a torque corresponding to twice the maximum torque of the second part of the motor.

4. The motor control method according to claim 1, characterized in that, in a speed region below a predetermined reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are the same; in a speed region greater than the reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are different.

5. The motor control method according to claim 4, characterized in that, the reference speed is set to the base speed of the first part of the motor.

6. The motor control method according to claim 1, characterized in that, the operating region where only the second part of the motor is driven is set in a speed region higher than the operating region where only the first part of the motor is driven.

7. The motor control method according to claim 1, characterized in that, the first part of the motor includes the first type of three-phase windings arranged at equal intervals in the circumferential direction around the rotation axis of the six-phase motor; the second part of the motor includes the second type of three-phase windings arranged at equal intervals in the circumferential direction around the rotation axis of the six-phase motor.

8. The motor control method according to claim 7, characterized in that, the first type of three-phase winding includes an A-phase winding, a B-phase winding, and a C-phase winding; the second type of three-phase winding includes an X-phase winding, a Y-phase winding, and a Z-phase winding; the A-phase winding, the B-phase winding, and the C-phase winding are arranged in sequence in the circumferential direction of the stator; the X-phase winding, the Y-phase winding, and the Z-phase winding are arranged in sequence in the direction in which the A-phase winding, the B-phase winding, and the C-phase winding are arranged.

9. The motor control method according to claim 8, characterized in that, The A-phase winding, B-phase winding, C-phase winding, X-phase winding, Y-phase winding, and Z-phase winding are configured to repeatedly form phases A, X, B, Y, C, and Z in sequence along the circumferential direction of the stator.

10. The motor control method according to claim 1, characterized in that the first type of three-phase winding and the second type of three-phase winding are formed by winding wires with different thicknesses.

11. The motor control method according to claim 1, characterized in that the number of turns of the first type of three-phase winding is more than 10% more than the number of turns of the second type of three-phase winding.

12. A motor control method for controlling a six-phase motor configured such that the maximum current applied to a first part of the motor is the same as the maximum current applied to a second part of the motor, the first part of the motor including a first type of three-phase winding and the second part of the motor including a second type of three-phase winding in which the number of turns connected in series per phase is less than that of the first type of three-phase winding, characterized in that in a speed region below a predetermined reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are the same; in a speed region greater than the reference speed, control is performed such that the phase angles of the first part of the motor and the second part of the motor are different.

13. The motor control method according to claim 12, characterized in that the reference speed is set to the base speed of the first part of the motor.

14. The motor control method according to claim 13, characterized in that the operating region for driving only the second part of the motor is set in a speed region higher than the operating region for driving only the first part of the motor.

15. The motor control method according to claim 14, characterized in that in a region where the required torque of the six-phase motor is below a torque corresponding to twice the maximum torque of the second part of the motor, control is performed such that the output torques of the first part of the motor and the second part of the motor are the same; in a region greater than twice the maximum torque of the second part of the motor, control is performed such that the output torques of the first part of the motor and the second part of the motor are different according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

16. A motor control method for controlling a six-phase motor configured such that the maximum current applied to a first part of the motor is the same as the maximum current applied to a second part of the motor, the first part of the motor including a first type of three-phase winding and the second part of the motor including a second type of three-phase winding in which the number of turns connected in series per phase is less than that of the first type of three-phase winding, characterized in that according to a predetermined reference speed and reference torque, the six-phase operation region for operating the six-phase motor in six phases is divided into four operation regions; in the six-phase first operation region among the four operation regions, control is performed such that the phase angles and torques of the first part of the motor and the second part of the motor are both the same, and the six-phase first operation region is a region where the speed is below the reference speed and the torque is below the reference torque; In the six-phase second operating region among the four operating regions, control is executed such that the phase angles of the first part of the motor and the second part of the motor are different but the torques are the same. The six-phase second operating region is a region where the rotational speed is greater than the reference rotational speed and the torque is below the reference torque; In the six-phase third operating region among the four operating regions, control is executed such that the phase angles of the first part of the motor and the second part of the motor are the same but the torques are different. The six-phase third operating region is a region where the rotational speed is below the reference rotational speed and the torque is greater than the reference torque; In the six-phase fourth operating region among the four operating regions, control is executed such that both the phase angles and the torques of the first part of the motor and the second part of the motor remain different. The six-phase fourth operating region is a region where the rotational speed is greater than the reference rotational speed and the torque is greater than the reference torque.

17. The motor control method according to claim 16, wherein, The reference rotational speed for dividing the four operating regions is set to the base rotational speed of the first part of the motor, and the reference torque is set to twice the maximum torque of the second part of the motor.

18. The motor control method according to claim 17, wherein, The three-phase second operating region for driving only the second part of the motor is set in a rotational speed region higher than the three-phase first operating region for driving only the first part of the motor.

19. The motor control method according to claim 18, wherein, The three-phase first operating region and the three-phase second operating region are set to overlap within the six-phase first operating region and the six-phase second operating region.

20. The motor control method according to claim 17, wherein, When control is executed such that the torques of the first part of the motor and the second part of the motor are different from each other, the output torque of the first part of the motor is made different from the output torque of the second part of the motor according to the ratio between the torque constant of the first part of the motor and the torque constant of the second part of the motor.

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