A method and system for suppressing common mode voltage of a six-phase motor

Abstract

The present invention provides a method and system for suppressing the common-mode voltage of a six-phase motor. The suppression system comprises: a six-phase motor, an inverter and a suppression module. The six-phase motor has a set speed. The six-phase motor has two three-phase subsystems, namely a first subsystem and a second subsystem. The six-phase motor is connected to the inverter. The inverter has a first bridge arm switch and a second bridge arm switch. The first bridge arm switch controls the first subsystem, and the second bridge arm switch controls the second subsystem. The suppression method comprises: controlling the six-phase motor to run at a set speed; obtaining a reference current of the six-phase motor; deriving a reference voltage according to the reference current; obtaining the action time of a reference vector; controlling the suppression module to output a switch instruction according to the reference voltage and the action time; the switch instruction is used to control the on and off of the first bridge arm switch and the second bridge arm switch, thereby suppressing the common-mode voltage of the six-phase motor, thereby avoiding the situation where the service life of the six-phase motor is reduced due to the interference of the common-mode voltage.

Description

Technical Field

[0001] The present invention relates to the technical field of six-phase motor common-mode electromagnetic interference suppression, and in particular to a six-phase motor common-mode voltage suppression method and suppression system. Background Art

[0002] With the continuous development of technology, six-phase motors, as a new type of drive device, have gradually attracted the interest of researchers and engineers. Compared with traditional single-phase permanent magnet synchronous motors, six-phase motors have a series of unique advantages, especially in low-voltage and high-power transmission. And with the rapid development of electric vehicles, industrial machinery, aerospace and other fields, the demand for low-voltage and high-power transmission is growing. In addition, traditional three-phase motors often have difficulty in achieving high power output under low voltage conditions, while six-phase motors can effectively solve this problem, providing higher power density and more stable performance.

[0003] However, due to the increase in the number of winding phases of the six-phase motor, the inverter needs more bridge arms, which makes the common-mode voltage path more, and then the electromagnetic interference noise is more serious. Common-mode voltage will not only increase the power consumption and loss of the motor system, but also may cause vibration, noise and other problems during the operation of the motor, thereby reducing the service life and performance of the motor. Especially in application scenarios with high requirements for motor operation stability and control accuracy, the common-mode voltage problem is more prominent. Common-mode voltage refers to the voltage that acts on the three-phase circuit of the motor at the same time. It may cause unbalanced current in the motor winding, thereby affecting the operation stability and performance of the motor. For a six-phase motor, it has two sets of three-phase windings, and each set of three-phase windings has a common-mode voltage path. After combining with each other, there will be more serious common-mode electromagnetic interference. Therefore, this application is aimed at a six-phase motor with two sets of three-phase windings with a 0° electrical angle difference. A method and a suppression device for the common-mode voltage of a six-phase motor are proposed to solve the above problems. Summary of the invention

[0004] Therefore, the present invention provides a method for suppressing the common-mode voltage of a six-phase motor, thereby reducing the interference of the common-mode voltage on the six-phase motor.

[0005] In order to solve the above problems, the present invention provides a method for suppressing the common mode voltage of a six-phase motor. The suppression method controls a suppression system. The suppression system includes: a six-phase motor, an inverter and a suppression module. The six-phase motor has a set speed. The six-phase motor has two three-phase subsystems, namely a first subsystem and a second subsystem. The six-phase motor is connected to the inverter. The inverter has a first bridge arm switch and a second bridge arm switch. The first bridge arm switch controls the first subsystem, and the second bridge arm switch controls the second subsystem. The suppression method includes: controlling the six-phase motor to run at a set speed; obtaining a reference current of the six-phase motor. , the reference current is the current when the six-phase motor runs at a set speed; the reference voltage is obtained according to the reference current; the action time of the reference vector is obtained by synthesizing the basic vector inherent in the six-phase motor; the control suppression module outputs a switch instruction according to the reference voltage and the action time; wherein the switch instruction is used to control the on and off of the first bridge arm switch and the second bridge arm switch, thereby suppressing the common mode voltage of the six-phase motor; the first subsystem includes: A1 phase, B1 phase and C1 phase, the second subsystem includes: A2 phase, B2 phase and C2 phase, and obtaining the action time of the basic vector specifically includes:

[0006] T S1 =T A1 +T B1 +T C1 ;

[0007] T A1 = ;

[0008] T B1 = ;

[0009] T C1 = ;

[0010] T S2 =T A2 +T B2 +T C2 ;

[0011] T A2 = ;

[0012] T B2 = ;

[0013] T C2 = ;

[0014] Among them, T S1 is the first action time of the reference vector of the first subsystem, T S2 is the second action time of the reference vector of the second subsystem, T A1is the action time of phase A1, T B1 is the action time of phase B1, T C1 is the action time of phase C1, T A2 is the action time of phase A2, T B2 is the action time of phase B2, T C2 is the action time of C2 phase, V ref is the reference voltage vector, U dc is the bus voltage, θ is the electrical angle of the six-phase motor, and the basic vectors selected by the two groups of three-phase subsystems are complementary to each other.

[0015] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the action time of the reference vector is related to the on-off time of the first bridge arm switch and the second bridge arm switch. Therefore, when controlling the switching state of the first bridge arm switch and the second bridge arm switch, it is necessary not only to control the switching state but also to clarify the duration of the switching state, so as to achieve a better effect of suppressing the common-mode voltage. The suppression module can output a switching instruction according to the reference voltage and the action time, thereby controlling the on-off and duration of the first bridge arm switch and the second bridge arm switch, thereby suppressing the six-phase motor from generating a common-mode voltage, and avoiding the situation where the service life of the six-phase motor is reduced due to the interference of the common-mode voltage. At the same time, a specific calculation method for the action time of the reference vector is given, so that the calculation method of the action time is more accurate.

[0016] Furthermore, the suppression system also includes a conversion device, and the suppression method also includes: controlling the conversion device to perform coordinate transformation on the reference current according to the corresponding relationship between the two-phase stationary coordinate system and the two-phase rotating coordinate system to obtain a transformed current.

[0017] Compared with the prior art, the technical effect achieved by adopting this technical solution is: the reference current is converted into a transformed current in a two-phase rotating coordinate system, so that the suppression module can obtain a reference voltage based on the reference current, thereby obtaining a control instruction to control the first bridge arm switch and the second bridge arm switch, thereby suppressing the six-phase motor from generating common-mode voltage.

[0018] Furthermore, the suppression system also includes a proportional-integral regulator, and the suppression method also includes: controlling the proportional-integral regulator to obtain a reference voltage according to the converted current.

[0019] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: a hardware device is set up to obtain a reference voltage based on the converted current, so that the suppression system can output switching instructions based on the reference voltage, thereby suppressing the six-phase motor from generating common-mode voltage, thereby avoiding interference of the six-phase motor due to the common-mode voltage.

[0020] Furthermore, the present invention also provides a suppression system, which executes the suppression method, and the suppression system includes: a six-phase motor; a suppression module, which outputs a switching instruction according to a reference voltage; and an inverter, which is connected to the six-phase motor.

[0021] Compared with the prior art, the technical effect achieved by adopting this technical solution is as follows: the suppression system of the present invention realizes the suppression method of any technical solution of the present invention, therefore, it has all the beneficial effects of the suppression method of any technical solution of the present invention, which will not be repeated here.

[0022] After adopting the technical solution of the present invention, the following technical effects can be achieved:

[0023] (1) The action time of the reference vector is related to the on-off time of the first bridge arm switch and the second bridge arm switch. Therefore, when controlling the switching state of the first bridge arm switch and the second bridge arm switch, it is necessary not only to control the switching state but also to clarify the duration of the switching state, so as to achieve a better effect of suppressing the common-mode voltage. The suppression module can output a switching instruction according to the reference voltage and the action time, thereby controlling the on-off and duration of the first bridge arm switch and the second bridge arm switch, thereby suppressing the generation of common-mode voltage by the six-phase motor, thereby avoiding the situation where the service life of the six-phase motor is reduced due to the interference of the common-mode voltage;

[0024] (2) Converting the reference current into a transformed current in a two-phase rotating coordinate system, so that the suppression module can obtain a reference voltage based on the reference current, thereby obtaining a control instruction to control the first bridge arm switch and the second bridge arm switch, thereby suppressing the common mode voltage generated by the six-phase motor;

[0025] (3) A specific calculation method for the action time of the reference vector is given, making the calculation method of the action time more accurate. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A flowchart of a six-phase motor common mode voltage suppression method provided by the present invention;

[0027] Figure 2 This is the axis distribution diagram of the six-phase motor winding;

[0028] Figure 3 A first voltage vector diagram which is a basic vector;

[0029] Figure 4 A second voltage vector diagram being a basic vector;

[0030] Figure 5 is the inverter topology diagram;

[0031] Figure 6 Schematic diagram of the switch state of the first bridge arm;

[0032] Figure 7 is a schematic diagram of the switch state of the second bridge arm;

[0033] Figure 8 Schematic diagram of the first effect of common mode voltage suppression;

[0034] Fig. 9 Schematic diagram of the first effect of common mode voltage suppression;

[0035] Fig.10 Schematic diagram of the inhibition system.

[0036] Description of reference numerals:

[0037] 100: suppression system; 110: six-phase motor; 120: speed regulator; 130: conversion device; 140: suppression module; 150: inverter; 160: proportional integral regulator. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The embodiment of the present invention provides a common mode voltage suppression method for a six-phase motor, as shown in the attached Figure 1 As shown, a method for suppressing common mode voltage of a six-phase motor includes:

[0040] S100, control the six-phase motor to run at a set speed;

[0041] S200, obtaining a reference current of the six-phase motor, where the reference current is the current when the six-phase motor runs at a set speed;

[0042] S300, obtaining a reference voltage according to a reference current;

[0043] S400, obtaining the action time of a reference vector, where the reference vector is synthesized by synthesizing the basic vectors inherent in the six-phase motor;

[0044] S500, the control inhibition module outputs a switch instruction according to the reference voltage and the action time.

[0045] For example, the suppression method provided in this application is for a six-phase motor with two sets of three-phase windings with a 0° electrical angle difference. The axes of the two sets of windings are as shown in the attached figure. Figure 2As shown; when the current running speed of the six-phase motor is inconsistent with the set speed, the current running speed of the six-phase motor is adjusted by the speed regulator so that the six-phase motor runs at the set speed, wherein the parameter setting of the motor is closely related to the motor characteristics, and the purpose of adjusting the current running current of the six-phase motor is achieved by adjusting the current running speed of the six-phase motor. When the current running speed is equal to the set speed, the current running current of the six-phase motor is equal to the reference current. The six-phase motor has two three-phase subsystems, namely the first subsystem and the second subsystem. The first subsystem has a first bridge arm switch, and the second subsystem has a second bridge arm switch. The on-off state of the first bridge arm switch and the second bridge arm switch suppresses the six-phase motor from generating common-mode voltage.

[0046] The suppression system further includes a speed regulator. When the running speed of the six-phase motor is inconsistent with the set speed, the speed regulator adjusts the running speed of the six-phase motor so that the running speed is equal to the set speed.

[0047] First, select the basic vector, use the volt-second balance principle to determine the length of the parallelogram side, and then make the basic vector synthesize the reference voltage vector through the parallelogram law. The volt-second balance principle is a fixed principle of vector synthesis in the field of motor control, that is, for an inductor in a stable state, the volt-second number of the switch on time (current rising section) must be equal to the volt-second number of the switch off time (current falling section), although the two have opposite signs. This also means that when the inductor voltage is plotted against time, the area of ​​the on-time curve must be equal to the area of ​​the off-time curve; as shown in the attached figure. Figure 3 and attached Figure 4 As shown, the basic vectors differ from each other by 120° electrical angle, and the basic vectors selected by the two subsystems are complementary to each other.

[0048] Among them, complementary sets mean that, assuming that the first subsystem selects the additional Figure 3 The basic vectors in the reference vector synthesis, then the second subsystem needs to select the additional Figure 4 The basic vectors in the reference vector synthesis, attached Figure 3 and attached Figure 4 The basic vectors in are complementary to each other.

[0049] For example, the first subsystem includes: A1 phase, B1 phase and C1 phase, the second subsystem includes: A2 phase, B2 phase and C2 phase, and obtaining the action time of the basic vector specifically includes:

[0050] T S1 =T A1 +T B1 +T C1 ;

[0051] T A1 = ;

[0052] T B1 = ;

[0053] T C1 = ;

[0054] T S2 =T A2 +T B2 +T C2 ;

[0055] T A2 = ;

[0056] T B2 = ;

[0057] T C2 = ;

[0058] Among them, T S1 is the first action time of the reference vector of the first subsystem, T S2 is the second action time of the reference vector of the second subsystem, T A1 is the action time of phase A1, T B1 is the action time of phase B1, T C1 is the action time of phase C1, T A2 is the action time of phase A2, T B2 is the action time of phase B2, T C2 is the action time of C2 phase, V ref is the reference voltage vector, U dc is the bus voltage, and θ is the electrical angle of the six-phase motor.

[0059] For example, the suppression system further includes a conversion device, and the suppression method further includes: controlling the conversion device to perform coordinate transformation on the reference current according to the correspondence between the two-phase stationary coordinate system and the two-phase rotating coordinate system to obtain a transformed current.

[0060] For example, converting the reference current into a transformed current in a two-phase rotating coordinate system makes it easier for the suppression module to derive a reference voltage based on the reference current, thereby deriving a control instruction to control the first bridge arm switch and the second bridge arm switch, thereby suppressing the six-phase motor from generating common-mode voltage.

[0061] Among them, in the process of transforming the reference current into a transformed current, the rotation transformation coefficient in the transformation array is 2 / 3. The transformation ensures the stability and accuracy of the system, allowing the motor to operate in the best state, thereby ensuring that the variable amplitude in the rotating coordinate system is consistent with the voltage and current variables in the stationary coordinate system.

[0062] For example, the suppression system further includes a proportional-integral regulator, and the suppression method further includes: controlling the proportional-integral regulator to obtain a reference voltage according to the transformed current.

[0063] It is additionally explained that after the reference voltage is obtained, the conversion device converts the reference voltage in the two-phase rotating coordinate system into a conversion voltage in the two-phase stationary coordinate system, and the suppression module obtains a switching instruction based on the conversion voltage and the action time.

[0064] For a six-phase motor whose axis of the first subsystem coincides with the axis of the second subsystem, such as Figure 2 As shown, the electrical angles of the two subsystems in space completely overlap, so the control of the two subsystems can be exactly the same. In order to suppress the common mode voltage of the first subsystem, the common mode voltage of the second subsystem and the average common mode voltage of the six-phase motor:

[0065] U NO1 = ;

[0066] U NO2 = ;

[0067] U NNO-AVG = ;

[0068] Among them, U NO1 is the common mode voltage of the first subsystem, U NO2 is the common mode voltage of the second subsystem, U NO-AVG is the average common mode voltage of the six-phase motor, U A1O , U B1O , U C1O is the voltage between the neutral point of the first subsystem and the neutral point of the capacitor, U A2O , U B2O , U C2O is the voltage between the neutral point of the second subsystem and the neutral point of the capacitor.

[0069] Supplementary explanation: The six-phase motor is connected to an inverter, which converts the input DC power into AC power, thereby driving the six-phase motor to operate. Figure 5 As shown, U A1O is the voltage between point O and point A1, U B1O is the voltage between point O and point B1, U C1O is the voltage between point O and point C1, U A2O is the voltage between point O and point A2, U B2O is the voltage between point O and point B2, U C2O is the voltage between point O and point C2.

[0070] The voltage input to the inverter is a DC voltage U dc After the DC voltage is input, it is stabilized by the capacitor bank and converted into AC output. The inverter has two three-phase bridge arm switches, namely: the first bridge arm switch and the second bridge arm switch. The first bridge arm switch controls the first subsystem of the six-phase motor, and the second bridge arm switch controls the second subsystem. Among them, the first bridge arm switch and the second bridge arm switch have three upper bridge arms and lower bridge arms respectively. An upper bridge arm and a lower bridge arm form a group, forming six groups, which control one phase of the six-phase motor.

[0071] The capacitor bank is composed of two capacitors connected in series, and the midpoint between the two capacitors is the neutral point of the capacitor bank.

[0072] The on-off state of the first bridge arm switch of the first subsystem is controlled as shown in the attached figure. Figure 6 As shown in the figure, 1 indicates connection and 0 indicates disconnection. Figure 5 As shown, Q 11 , Q 12 and Q 13 Together they form the first bridge arm switch, Q 21 , Q 22 and Q 23 Together they form the second bridge arm switch, one phase of which has an upper bridge arm and a lower bridge arm, such as Q 11a Q 11 The upper arm, Q 11b Q 11 The lower bridge arm of the connected state is that the upper bridge arm is connected and the lower bridge arm is disconnected, and the disconnected state is that the lower bridge arm is connected and the upper bridge arm is disconnected.

[0073] According to the action time of the basic vector, the length of the unit time is determined, and then the on-off duration of the first bridge arm switch is determined.

[0074] As attached Figure 6 As shown, the Q of the first bridge arm switch 11 Control the first phase of the first subsystem, Q 11 First it is connected and lasts for one unit time, then it switches to a disconnected state and lasts for three unit times, then it is connected again and lasts for one unit time.

[0075] Q 12 The second phase of the first subsystem is controlled to be closed first, maintained for one unit time, switched to the connected state, maintained for one unit time, switched to the disconnected state, and maintained for one unit time, then switched to the connected state, maintained for one unit time, and finally switched to the disconnected state, and maintained for one unit time.

[0076] Q 13 Control the third phase of the first subsystem, Q 13First disconnect, the disconnected state lasts for two unit times, then switch to the connected state, the connected state lasts for one unit time, and then switch to the disconnected state, the disconnected state lasts for two unit times.

[0077] Control the on / off state of the second bridge arm switch of the second subsystem Figure 7 As shown, the Q of the second bridge arm switch 21 Controls the first phase of the second subsystem, Q 21 Connected, the connected state lasts for one unit time, Q 21 Switch from connected to disconnected state for one unit time, then switch from disconnected state to connected state for one unit time, then switch from connected state to disconnected state for one unit time, and finally, switch from disconnected state to open state for one unit time.

[0078] Q 22 Control the second phase of the second subsystem, Q 22 Connected, the connected state lasts for two unit times, then switches to the disconnected state, the disconnected state lasts for one unit time, and finally, switches from the disconnected state to the connected state, and the connected state lasts for two unit times.

[0079] Q 23 Controls the third phase of the second subsystem, Q 23 Disconnected for one unit time, switched from disconnected state to connected state for three unit time, and finally switched back to disconnected state for one unit time.

[0080] Attached Figure 6 and attached Figure 7 The on-off states and durations of the first bridge arm switch and the second bridge arm switch when suppressing the six-phase motor from generating common-mode voltage are also given, thereby suppressing the six-phase motor from generating common-mode voltage.

[0081] As attached Figure 8 As shown, in order to verify whether the method for suppressing the common-mode voltage of the six-phase motor provided in the present application is effective, the common-mode voltage of the suppressed six-phase motor is monitored, and the common-mode voltage of the first subsystem, the common-mode voltage of the second subsystem, and the average common-mode voltage are as shown in FIG. Figure 8 As shown, they are constant constants - U dc / 6, U dc / 6 and 0, the voltage directions of the first subsystem and the second subsystem are opposite, the two cancel each other out, and the average common-mode voltage is suppressed.

[0082] As attached Fig. 9As shown in the figure, the dotted line is the curve of the common mode voltage change of the first subsystem. The amplitude and frequency of the common mode voltage of the first subsystem are obviously suppressed. The common mode voltage amplitude is -Udc / 6 and remains unchanged in one cycle. The solid line in the figure is the change curve of the common mode voltage without suppression. Fig. 9 It can be concluded that without suppressing the common-mode voltage, the amplitude of the common-mode voltage generated by the six-phase motor is constantly changing, and the frequency of the change is relatively high.

[0083] It can be concluded that the suppression method provided by the present invention can effectively suppress the common-mode voltage of the six-phase motor. The voltage directions of the first subsystem and the second subsystem are opposite, and the two cancel each other out, and the average common-mode voltage is 0.

[0084] The present invention also provides a suppression system 100, the suppression system 100 performs a suppression method, as shown in the attached Fig.10 As shown, the suppression system 100 includes: a six-phase motor 110 , a suppression module 140 and an inverter 150 . The suppression module 140 outputs a switch instruction according to a reference voltage and an action time voltage. The inverter 150 is connected to the six-phase motor 110 .

[0085] The six-phase motor has two subsystems. The electromagnetic conditions of the two subsystems are almost the same. When the two subsystems operate symmetrically, the control parameters of the two subsystems are the same. The symmetrical operation of the two subsystems means that the loads or currents of the two subsystems are the same. Fig.10 As shown, the running speed W1 of the six-phase motor is obtained, and it is determined whether the running speed W1 is equal to the set speed W. If they are not equal, the speed regulator 120 is controlled to adjust the running speed W1 so that the running speed W1 is equal to the set speed W; the reference current of the six-phase motor is obtained, wherein the six-phase motor has two subsystems, and therefore has two reference currents, which are I1 and I2, respectively, and the control conversion device 130 converts the reference currents I1 and I2 into the transformation current I in the rotating coordinate system s1 and I s2 The proportional-integral controller 160 converts the current I s1 and I s2 The reference voltages U1 and U2 are obtained, and the conversion device 130 converts the reference voltages U1 and U2 into voltage values ​​in a stationary coordinate system to obtain a conversion voltage U S1 and U S2 , the suppression module 140 transforms the voltage U S1 and U S2 The control instructions S1 and S2 are output, and the inverter 150 is connected to the six-phase motor 110, and controls the six-phase motor through the first bridge arm switch and the second bridge arm switch, so as to suppress the common mode voltage generated by the six-phase motor.

[0086] Where I1 is the reference current of the first subsystem, I2 is the reference current of the second subsystem, and I s1 is the transformed current of the first subsystem, which is the current value of the reference current I1 in the rotating coordinate system, I s2 is the conversion current of the second subsystem, is the current value of the reference current I2 in the rotating coordinate system, U1 is the reference voltage of the first subsystem, U2 is the reference voltage of the second subsystem, and U S1 is the transformation voltage of the first subsystem, which is the voltage value of the reference voltage U1 in the stationary coordinate system, U S2 is the conversion voltage of the second subsystem, which is the voltage value of the reference voltage U2 in the stationary coordinate system, S1 is the control instruction of the first bridge arm switch, and S2 is the control instruction of the second bridge arm switch.

[0087] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for suppressing common mode voltage of a six-phase motor, characterized in that: The suppression method controls a suppression system, the suppression system comprising: a six-phase motor, an inverter and a suppression module, the six-phase motor having a set speed, the six-phase motor having two groups of three-phase subsystems, namely a first subsystem and a second subsystem, the six-phase motor being connected to the inverter, the inverter having a first bridge arm switch and a second bridge arm switch, the first bridge arm switch controlling the first subsystem, the second bridge arm switch controlling the second subsystem, the suppression method comprising: Controlling the six-phase motor to run at the set speed; Obtaining a reference current of the six-phase motor, wherein the reference current is the current of the six-phase motor when running at the set speed; deriving a reference voltage according to the reference current; Obtaining an action time of a reference vector, wherein the reference vector is synthesized by synthesizing a basic vector inherent to the six-phase motor; Controlling the suppression module to output a switch instruction according to the reference voltage and the action time; Wherein, the switch instruction is used to control the on and off of the first bridge arm switch and the second bridge arm switch, thereby suppressing the common mode voltage of the six-phase motor; The first subsystem includes: phase A1, phase B1 and phase C1, the second subsystem includes phase A2, phase B2 and phase C2, and the obtaining of the action time of the reference vector specifically includes: T S1 =T A1 +T B1 +T C1 ; T A1 = ； T B1 = ； T C1 = ； T S2 =T A2 +T B2 +T C2 ; T A2 = ； T B2 = ； T C2 = ； Among them, T S1 is the action time of the reference vector of the first subsystem, T S2 is the action time of the reference vector of the second subsystem, T A1 is the action time of the A1 phase, T B1 is the action time of the B1 phase, T C1 is the action time of the C1 phase, T A2 is the action time of the A2 phase, T B2 is the action time of the B2 phase, T C2 is the action time of the C2 phase, V ref is the reference voltage vector, U dc is the bus voltage, θ is the electrical angle of the six-phase motor; The basic vectors selected by the two groups of three-phase subsystems are complementary to each other.

2. The suppression method according to claim 1, characterized in that: The suppression system further includes a conversion device, and the suppression method further includes: The conversion device is controlled to perform coordinate transformation on the reference current according to the corresponding relationship between the two-phase stationary coordinate system and the two-phase rotating coordinate system to obtain the transformed current.

3. The suppression method according to claim 2, characterized in that: The suppression system further includes a proportional-integral regulator, and the suppression method further includes: The proportional-integral regulator is controlled to obtain the reference voltage according to the conversion current.

4. A suppression system, characterized in that: The suppression system (100) performs the suppression method according to any one of claims 1 to 3, and the suppression system (100) comprises: Six-phase motor (110); A suppression module (140), wherein the suppression module (140) outputs the switch instruction according to the reference voltage and the action time; An inverter (150), the inverter (150) being connected to the six-phase motor (110).

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