Full-bridge carrier phase-shifted multi-three-phase permanent magnet synchronous motor high-frequency vibration suppression system and motor system

Abstract

The application discloses a multi-three-phase permanent magnet synchronous motor high-frequency vibration suppression system based on full-bridge carrier phase shift and a motor system, and belongs to the technical field of motor driving. The system comprises 3N full-bridge inverters connected with 3N phase windings one by one, wherein N is an even number; and a controller connected with each full-bridge inverter, which is used for performing the following steps: screening out motor modal inherent frequencies farthest from the frequency of the largest amplitude and corresponding modal orders s; solving carrier phase differences between each set of three-phase windings in order to minimize spatial order harmonic components of high-frequency electromagnetic force, and the main high-frequency electromagnetic force space order is consistent with s; solving carrier phase differences between windings in each set of three-phase windings in order to minimize the main high-frequency magnetic field; solving the carrier phase of each phase winding, and performing carrier phase shift modulation to obtain switching driving signals of each full-bridge inverter. The application can fully consider the carrier phase shift freedom of all phases, and further improve the high-frequency vibration suppression effect.

Description

Technical Field

[0001] This invention belongs to the field of motor drive technology, and more specifically, relates to a high-frequency vibration suppression system and motor system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shift. Background Technology

[0002] Three-phase permanent magnet synchronous motors (PMSMs) possess advantages such as high power density, low torque ripple, and strong fault tolerance, making them widely used in new energy vehicles, aerospace, and other applications. Variable frequency drive systems, as the core of DC-AC power conversion equipment, are often used for the drive control of PMSMs. To achieve flexible motor speed regulation, pulse width modulation (PWM) technology based on the volt-second equivalent principle is typically used to control power switching devices, outputting a high-frequency voltage pulse sequence to equivalently generate the required AC voltage. However, while PWM technology reduces harmonic losses and improves system dynamic response performance, it also introduces switching frequency current ripple into the motor stator windings. These high-frequency current ripples generate high-frequency electromagnetic forces in the motor air gap, which act on the stator tooth surface, causing the motor to generate high-frequency radial electromagnetic vibration.

[0003] High-frequency vibration in electric motors can cause several problems: First, it can loosen motor connections, accelerate bearing wear, and shorten motor lifespan. Second, it can cause noise pollution, affecting user experience. Finally, motor vibration noise can reduce the overall performance of the motor system, especially in scenarios like submarines and surface ships, where the vibration spectrum makes them more susceptible to sonar detection and attack.

[0004] Therefore, vibration reduction and noise reduction technologies for motors are being studied by an increasing number of scholars. Currently, the main active suppression methods for high-frequency motor vibration include: 1) Using variable switching frequency modulation technology, the switching frequency is randomly varied within a set frequency band, distributing high-frequency harmonic current energy within the band and suppressing vibrations at the corresponding frequencies. However, this method expands the frequency spectrum, increases the risk of motor resonance, and also affects the motor control bandwidth. 2) Applying carrier phase-shifting technology to multi-phase three-phase permanent magnet synchronous motors with co-slot structures, etc., to cancel out high-frequency magnetic fields at specific frequencies, thereby reducing the amplitude of electromagnetic excitation forces of specific orders. However, this method usually drastically worsens the amplitude of high-frequency harmonic currents, reducing power quality. In addition, some methods have proposed suppressing high-frequency PWM vibration in multi-phase three-phase permanent magnet synchronous motors by changing the phase of the current harmonics generated by PWM modulation in each set of three-phase windings. However, this method only considers the carrier phase difference between each set of three-phase windings, and its vibration reduction effect is limited. Summary of the Invention

[0005] To address the shortcomings and improvement needs of existing technologies, this invention provides a high-frequency vibration suppression system and motor system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting. The purpose is to fully consider the carrier phase shifting degrees of freedom of all phases in the multi-phase three-phase permanent magnet synchronous motor and further improve the high-frequency vibration suppression effect.

[0006] To achieve the above objectives, according to one aspect of the present invention, a high-frequency vibration suppression system for a multi-phase permanent magnet synchronous motor based on full-bridge carrier phase shift is provided. The multi-phase permanent magnet synchronous motor includes N sets of three-phase windings arranged sequentially along the stator circumference, where N is an even number and the windings are concentrated windings. The system includes: a controller and 3N full-bridge inverters. 3N full-bridge inverters are connected one-to-one with 3N phase windings; The controller is connected to each full-bridge inverter and is used to perform the following steps: S1: Select the frequency with the largest vibration amplitude from even-numbered multiples of the switching frequency. And select the distance frequency from the natural frequencies corresponding to each mode of the motor. farthest natural frequency and the corresponding modal order s; S2: With the goal of minimizing the spatial order harmonic components of high-frequency electromagnetic force and ensuring that the spatial order of the main high-frequency electromagnetic force is consistent with s, solve for the carrier phase difference between each set of three-phase windings in N sets of three-phase windings; the main spatial order of high-frequency electromagnetic force is the spatial order of electromagnetic force formed by the harmonics with the largest amplitude in the high-frequency magnetic field. S3: While keeping the carrier phase difference between each set of three-phase windings constant, with the goal of minimizing the main oscillating high-frequency magnetic field, solve for the carrier phase difference of the windings within each set of three-phase windings; the main oscillating high-frequency magnetic field harmonic components are the harmonic components in the high-frequency magnetic field with amplitudes greater than a preset threshold that can generate s-order electromagnetic forces. S4: Solve the carrier phase of each phase winding based on the carrier phase difference between each set of three-phase windings and the carrier phase difference within each set of three-phase windings, and perform carrier phase shift modulation based on the carrier phase of each phase winding to obtain the switching drive signal of each full-bridge inverter.

[0007] Furthermore, in step S2, the carrier phase difference between each set of three-phase windings in the N sets of three-phase windings is symmetrical.

[0008] Furthermore, if N=4, then the carrier phase differences between each set of three-phase windings are 0 and θ, respectively. c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, and θ, respectively. c θ c ; If N=6, then the carrier phase differences between each set of three-phase windings are 0 and θ, respectively.c , 0, θ c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, 0, and θ, respectively. c θ c θ c ; If N=8, then the carrier phase differences between each set of three-phase windings are 0 and θ, respectively. c , 0, θ c , 0, θ c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, 0, 0, θ respectively. c θ c θ c θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, and θ, respectively. c θ c , 0, 0, θ c θ c ; Where, θ c The carrier phase difference is non-zero.

[0009] Further, step S3 includes: Fix the carrier phase of one phase, and iterate through the carrier phases of the other two phases; For each carrier phase combination traversed, while keeping the carrier phase difference between each set of three-phase windings constant, the corresponding high-frequency magnetic field is calculated, and the main oscillating high-frequency magnetic field is extracted. The carrier phase combination with the smallest amplitude of the high-frequency magnetic field that mainly causes vibration is taken as the optimal carrier phase combination within the set, and the corresponding carrier phase difference is determined as the carrier phase difference between the windings within each set of three-phase windings.

[0010] Furthermore, the motor modes and their corresponding natural frequencies are obtained through impact testing or finite element simulation.

[0011] Furthermore, the formula for calculating high-frequency electromagnetic force is: ; in, For even numbers greater than or equal to 2, It is an odd number; Indicates the angle of space machinery. Indicates time; This represents the radial permeability constant of the air gap. Indicates the permeability of free space; express Step rotor magnetic field, This represents the number of rotor pole pairs; The fundamental angular frequency, Indicates the initial phase of the fundamental magnetic field; Indicates that the frequency in the winding is The high-frequency magnetomotive force generated by the harmonic current. This is the carrier angular frequency.

[0012] Furthermore, high-frequency magnetomotive force The expression is: ; in, Indicates the winding sequence number. Indicates the first The frequency in the phase winding is Harmonic currents, Indicates the first The winding function of the phase winding.

[0013] Furthermore, harmonic currents and winding function The expressions are as follows: ; ; in, The amplitude of the harmonic current. For the first Phase carrier phase, For the first Phase of fundamental wave, The initial phase angle; This indicates the order of the Fourier decomposition of the winding function. For the corresponding amplitude coefficient, The initial phase angle, This represents the spatial phase difference between two adjacent phase windings.

[0014] According to another aspect of the present invention, a multi-phase permanent magnet synchronous motor system is provided, comprising: a multi-phase permanent magnet synchronous motor and a high-frequency vibration suppression system for a multi-phase permanent magnet synchronous motor based on full-bridge carrier phase shifting provided by the present invention; Among them, the multi-phase three-phase permanent magnet synchronous motor includes N sets of three-phase windings arranged sequentially along the stator circumference, where N is an even number and the windings are concentrated windings.

[0015] In summary, the above-described technical solutions conceived in this invention can achieve the following beneficial effects: (1) After determining the frequency and order s that is farthest from the frequency with the largest vibration in the natural frequencies corresponding to each mode of the motor, the present invention aims to minimize the spatial order harmonic components of the high-frequency electromagnetic force and ensure that the spatial order of the main high-frequency electromagnetic force is consistent with s. The carrier phase difference between each set of three-phase windings in N sets of three-phase windings is solved. On this basis, the carrier phase difference in each set of three-phase windings is solved with the goal of minimizing the main vibration-causing high-frequency magnetic field. In this way, the carrier phase shift freedom of all phases of the motor can be fully explored, and the suppression effect of high-frequency electromagnetic vibration of the motor can be effectively improved.

[0016] (2) This invention proposes high-frequency electromagnetic force under different phase shift angles. The calculation method can quickly calculate electromagnetic force, providing an efficient and reliable basis for fully exploring the carrier phase shift degrees of freedom of all phases of the motor. Attached Figure Description

[0017] Figure 1 This is a connection diagram of a multi-phase three-phase permanent magnet synchronous motor and a full-bridge inverter provided in an embodiment of the present invention.

[0018] Figure 2 A flowchart of a high-frequency vibration suppression method provided in an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the transfer function curve obtained from modal testing in an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the high-frequency magnetic field under the two vibration reduction and phase shifting methods provided by the present invention.

[0021] Figure 5 This is a schematic diagram of carrier phase shifting provided by the present invention.

[0022] Figure 6 This is a comparison diagram of the high-frequency vibration suppression effects of two vibration reduction and phase shifting methods provided in the embodiments of the present invention. Detailed Implementation

[0023] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention. Furthermore, the technical features involved in the various embodiments of this invention described below can be combined with each other as long as they do not conflict with each other.

[0024] In this invention, the terms "first," "second," etc. (if present) in the invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0025] To further improve the suppression effect of high-frequency vibration in multi-phase three-phase permanent magnet synchronous motors, this invention provides a high-frequency vibration suppression system and motor system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shift. The overall concept is to consider the carrier phase difference between each set of three-phase windings, and further consider the carrier phase difference between each phase winding within each set of three-phase windings, thereby fully exploring the carrier phase shift freedom of all phases of the motor, and finally achieving the best suppression effect of high-frequency electromagnetic vibration of the motor.

[0026] The multi-phase permanent magnet synchronous motor to which this invention applies comprises N sets of three-phase windings arranged sequentially along the stator circumference, where N is an even number. Furthermore, the windings are concentrated windings to ensure a low coupling coefficient between each phase winding. Without loss of generality, the following embodiments use a permanent magnet synchronous motor with 4 sets of three-phase windings (a total of 4*3=12 phase windings) as an example for illustration. The structural parameters and operating conditions of this motor are shown in Table 1.

[0027] Table 1. Motor structural parameters and operating conditions

[0028] The following is an example.

[0029] Example 1: A high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting. For example... Figure 1 As shown, the multi-phase three-phase permanent magnet synchronous motor includes four sets of three-phase windings arranged sequentially along the stator circumference. The windings are concentrated windings, so the mutual inductance between the windings is very small and can be regarded as decoupled. That is, the high-frequency harmonic current of the twelve-phase winding is considered to be only related to the full-bridge modulation of its own phase.

[0030] To fully exploit the carrier phase shift freedom of all phases of the motor, in this embodiment, each phase winding is independently controlled by a corresponding full-bridge inverter. Accordingly, in this embodiment, a total of 12 full-bridge inverters are set up and connected one-to-one with the 12 phase windings, as follows: Figure 1 As shown, the two ends of each phase winding are connected to the midpoints of the two bridge arms of the corresponding full-bridge inverter. It is easy to understand that when the number of three-phase windings in a multi-phase permanent magnet synchronous motor changes, the number of full-bridge inverters needs to be adjusted accordingly.

[0031] This embodiment also includes a controller connected to each full-bridge inverter to execute a high-frequency vibration suppression method and ultimately generate a switching drive signal that can suppress high-frequency vibration.

[0032] like Figure 2 As shown, in this embodiment, the high-frequency vibration suppression method executed by the controller includes the following steps: S1: Select the frequency with the largest vibration amplitude from even-numbered multiples of the switching frequency. And select the distance frequency from the natural frequencies corresponding to each mode of the motor. farthest natural frequency and the corresponding modal order s; S2: With the goal of minimizing the spatial order harmonic components of high-frequency electromagnetic force and ensuring that the spatial order of the main high-frequency electromagnetic force is consistent with s, solve for the carrier phase difference between each set of three-phase windings in N sets of three-phase windings; the main spatial order of high-frequency electromagnetic force is the spatial order of electromagnetic force formed by the harmonics with the largest amplitude in the high-frequency magnetic field. S3: While keeping the carrier phase difference between each set of three-phase windings constant, with the goal of minimizing the main oscillating high-frequency magnetic field, solve for the carrier phase difference within each set of three-phase windings; the main oscillating high-frequency magnetic field harmonic components are the harmonic components in the high-frequency magnetic field with amplitudes greater than a preset threshold that can generate s-order electromagnetic forces. S4: Solve the carrier phase of each phase winding based on the carrier phase difference between each set of three-phase windings and the carrier phase difference between windings within each set of three-phase windings, and perform carrier phase shift modulation based on the carrier phase of each phase winding to obtain the switching drive signal of each full-bridge inverter.

[0033] The following provides a further explanation of the specific implementation methods for each step.

[0034] In this embodiment, the motor's various modules and their corresponding natural frequencies need to be determined in advance. In practical applications, the motor modes and their natural frequencies within the target frequency band can be measured through experiments such as finite element simulation or the impact test. Optionally, in this embodiment, the impact test is used for measurement, and the resulting motor modal response curve is shown below. Figure 3 As shown in the figure. According to the measurement results, in this embodiment, the spatial order and corresponding natural frequency of each mode of the multi-phase permanent magnet synchronous motor are as follows: 0th order, 11963Hz; 2nd order, 1983Hz; 3rd order, 3936Hz; 4th order, 6014Hz.

[0035] Further testing revealed that the frequency with the maximum vibration amplitude was approximately twice the switching frequency, i.e. Accordingly, in step S1 above, the distance frequency... The farthest natural frequency is 1983 Hz, corresponding to a modal order of 2, i.e., s=2.

[0036] In step S2 above, the goal is to minimize the spatial order harmonic components of the high-frequency electromagnetic force and ensure that the spatial order of the main high-frequency electromagnetic force is consistent with s. The carrier phase difference between each set of three-phase windings in N sets of three-phase windings is solved. This carrier phase difference is the optimal inter-set carrier phase difference, which is beneficial to achieving optimal vibration reduction.

[0037] To facilitate rapid calculation of high-frequency electromagnetic forces, this embodiment proposes a novel method for calculating high-frequency electromagnetic forces, including: (a) Calculate the winding function of the single-phase winding, which is only related to the connection method of the winding (connection and arrangement order). The carrier phase of the phase winding is denoted as , for the current harmonics near the ( is an even number greater than or equal to 2) times the switching frequency, its phase changes by , and the amplitude remains basically unchanged.

[0038] In this embodiment, the single-phase winding of the motor has only one coil, occupying a 30° space angle. Therefore, the waveform of this winding function is a "Ji" - shaped square wave with an opening of 30° on the 360° circumference. For subsequent analysis of the spatial order of the electromagnetic force, the Fourier decomposition of this waveform in space can be performed here. That is, the winding function of the first-phase winding is: ; where, is the order after the Fourier decomposition of the winding function, is its amplitude coefficient, is the spatial mechanical angle, is the initial phase angle. It should be emphasized that the connection order of the windings of most motors in each phase is the same. Therefore, the winding functions of all phases are the same, except for a spatial phase difference . Therefore, the winding function of the phase winding is expressed as: .

[0039] (b) For the full-bridge topology, the harmonic current frequency is , is an even number greater than or equal to 2, is an odd number, is the fundamental angular frequency, is the carrier angular frequency. Here, taking the vibration suppression near twice the switching frequency as an example, mainly consider and . The harmonic current with a frequency of in the phase winding is: ; where, represents time; is the amplitude of the harmonic current, is the carrier phase of the phase, is the fundamental phase of the phase, is the initial phase angle.

[0040] The product of the high-frequency current in each phase and the winding function is the high-frequency magnetomotive force generated by that phase. Superimposing the twelve phase magnetomotive forces yields the air-gap composite magnetomotive force. That is: .

[0041] (c) Analyze the carrier phase shift combinations between multiple sets of three phases to minimize the spatial order harmonic components of the high-frequency electromagnetic force and ensure that the main high-frequency force order is consistent with the selected resonant mode order 2. Since the windings are decoupled in this embodiment, the stator slotting and rotor magnetic saturation effects can be ignored, thus the high-frequency magnetic field is proportional to the high-frequency magnetomotive force. According to the air gap synthesis magnetomotive force calculation method proposed in the previous step, when the carrier phase difference between the four sets of three phases is 0-90°-0-90°, the amplitudes of the 2nd and 6th orders in the high-frequency magnetic field are relatively large. According to Maxwell's tension formula, the high-frequency electromagnetic force mainly originates from the high-frequency magnetic field and... Rank ( In this embodiment, the number of rotor pole pairs is... Rotor magnetic field Multiplication effect, that is: ; in, This represents the radial permeability constant of the air gap. Indicates the permeability of free space; This indicates the initial phase of the fundamental magnetic field.

[0042] By performing spatial Fourier decomposition on the high-frequency electromagnetic force, the spatial order components of the electromagnetic force can be obtained.

[0043] According to the product-difference relationship of trigonometric functions, when the carrier phase difference between the four sets of three-phase windings is 0-90°-0-90°, the second-order and sixth-order high-frequency magnetic fields mainly form the second-order electromagnetic force, which is consistent with the motor mode order selected in the previous step.

[0044] Based on the analysis, the kit carrier phase difference determined in step S2 of this embodiment can effectively reduce high-frequency vibration in multi-phase three-phase permanent magnet synchronous motors.

[0045] According to the existing method, after determining the carrier phase difference between the four sets of three-phase windings, the three-phase windings within the set will adopt a unified carrier phase. Specifically, when the carrier phase difference between the four sets of three-phase windings is 0-90°-0-90°, the carrier phases adopted by the four sets of three-phase windings are 0, 90°, 0, 90° respectively.

[0046] In practical applications, when the carrier phase difference of the three-phase windings between the two units has a symmetrical form, it can achieve the effect of minimizing the spatial order harmonic components of the high-frequency electromagnetic force. After determining the carrier phase difference combination with a symmetrical form, the specific carrier phase difference combination can be further determined with the goal of the main high-frequency force order being consistent with the selected resonant mode order. In this way, the optimal carrier phase difference combination between the two units can be quickly determined.

[0047] It is easy to understand that when a multi-phase permanent magnet synchronous motor contains four sets of three-phase windings, the carrier phase difference with a symmetrical form is: 0, θ c , 0, θ c , or 0, 0, θ c θ c When a multi-phase permanent magnet synchronous motor contains 6 sets of three-phase windings, the carrier phase difference with symmetrical characteristics is as follows: 0, θ c , 0, θ c , 0, θ c Or, 0, 0, 0, θ c θ c θ c When a multi-phase permanent magnet synchronous motor contains 8 sets of three-phase windings, the carrier phase difference with symmetrical characteristics is as follows: 0, θ c , 0, θ c , 0, θ c , 0, θ c Or, 0, 0, 0, θ c θ c θ c θ c Or, for 0, 0, θ c θ c , 0, 0, θ c θ c And so on.

[0048] Step S3 of this embodiment, based on step S2, further analyzes the carrier phase difference between each phase winding within each three-phase winding set. This step can further optimize the amplitude of the high-frequency magnetic field, making the amplitude of the main oscillating high-frequency magnetic field zero or as small as possible. Taking the A-phase carrier within each three-phase set as a reference, the carrier phases of phases B and C are traversed with two degrees of freedom to calculate the variation law of the air gap high-frequency magnetic field. For the motor studied in this embodiment, when the carrier phase within each three-phase set maintains a phase difference relationship of 0°-90°-0°, the high-frequency magnetic field with a spatial order of 6±12k (k=0, 1...) near the second switching frequency is completely eliminated. Therefore, the second-order equal-frequency electromagnetic harmonics will also be reduced accordingly, which means that the excitation source of high-frequency vibration is reduced, thus further reducing high-frequency vibration. At this time, the twelve-phase carrier phases are arranged alternately at 0° and 90°.

[0049] Figure 4 The diagram shows the air gap high-frequency magnetic field components corresponding to the carrier phase determined by this embodiment and the carrier phase determined by existing methods. For simplicity, the carrier phase determined by existing methods is abbreviated as "0-90°-0-90°", and the carrier phase determined by this embodiment is abbreviated as "12DPS-90°". The air gap high-frequency magnetic field components corresponding to the two methods are as follows: Figure 4 As shown on the left and right sides, the comparison reveals that this embodiment, based on the determined inter-unit carrier phase combination, analyzes the carrier phase difference between phases within each three-phase unit, thereby determining the carrier phase of each phase, which can further reduce high-frequency vibration.

[0050] After determining the carrier phase of each phase, closed-loop speed control of the motor is implemented, and the data is sent to the modulation module. Normally, all phases share a single triangular carrier wave during modulation; however, this embodiment requires phase shifting of the twelve carrier waves, such as... Figure 5 As shown, the phase shift value is consistent with the previously calculated carrier phase, and this effect can be achieved by changing the initial count value of the triangular carrier, etc.

[0051] Further based on Figure 6 The quantification results show that, without carrier phase shifting, the maximum vibration acceleration of the multi-phase three-phase permanent magnet synchronous motor is 17.24 m / s². 2 Using existing methods, considering only the carrier phase difference between each set of three-phase windings, the maximum vibration acceleration of the multi-phase three-phase permanent magnet synchronous motor is reduced to 8.97 m / s². 2 Using the method provided in this embodiment, and fully considering the degrees of freedom of each phase, the maximum vibration acceleration of the multi-phase three-phase permanent magnet synchronous motor is further reduced to 3.99 m / s². 2 Based on this result, it can be seen that this embodiment can further improve the high-frequency vibration suppression effect.

[0052] In summary, this embodiment utilizes software modulation to actively suppress high-frequency vibrations, requiring no additional hardware. It achieves amplitude reduction of high-frequency vibrations at a fixed frequency without altering the previously set switching frequency, taking into account factors such as power quality and operating efficiency. The qualitative calculation method for high-frequency electromagnetic forces under different carrier phase shift combinations has clear physical meaning and is easily extended to low-coupling multi-phase motors with various pole-slot combinations. It has a low computational burden, saving significant computation time compared to finite element simulations with short step sizes, and can provide guidance for selecting the optimal phase shift angle. Finally, by fully considering the carrier phase shift degrees of freedom for all phases, it achieves superior vibration suppression compared to considering only the carrier phase shift between each set of three-phase windings.

[0053] Example 2: A multi-phase three-phase permanent magnet synchronous motor system includes: a multi-phase three-phase permanent magnet synchronous motor and the high-frequency vibration suppression system for the multi-phase three-phase permanent magnet synchronous motor based on full-bridge carrier phase shifting provided in Embodiment 1 above; Among them, the multi-phase three-phase permanent magnet synchronous motor includes four sets of three-phase windings arranged sequentially along the stator circumference, and the windings are concentrated windings.

[0054] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-frequency vibration suppression system for a multi-phase three-phase permanent magnet synchronous motor based on full-bridge carrier phase shifting, wherein the multi-phase three-phase permanent magnet synchronous motor comprises N sets of three-phase windings arranged sequentially along the stator circumference, where N is an even number, and the windings are concentrated windings; characterized in that, The system includes: a controller and 3N full-bridge inverters; 3N full-bridge inverters are connected one-to-one with 3N phase windings; The controller is connected to each full-bridge inverter and is used to perform the following steps: S1: Select the frequency with the largest vibration amplitude from even-numbered multiples of the switching frequency. And select the distance frequency from the natural frequencies corresponding to each mode of the motor. farthest natural frequency and the corresponding modal order s; S2: With the goal of minimizing the spatial order harmonic components of high-frequency electromagnetic force and ensuring that the spatial order of the main high-frequency electromagnetic force is consistent with s, solve for the carrier phase difference between each set of three-phase windings in N sets of three-phase windings; the main spatial order of high-frequency electromagnetic force is the spatial order of electromagnetic force formed by the harmonics with the largest amplitude in the high-frequency magnetic field. S3: While keeping the carrier phase difference between each set of three-phase windings constant, with the goal of minimizing the main oscillating high-frequency magnetic field, solve for the carrier phase difference between the windings in each set of three-phase windings; the main oscillating high-frequency magnetic field harmonic components are the harmonic components in the high-frequency magnetic field with amplitudes greater than a preset threshold that can generate s-order electromagnetic force. S4: Solve the carrier phase of each phase winding based on the carrier phase difference between each set of three-phase windings and the carrier phase difference within each set of three-phase windings, and perform carrier phase shift modulation based on the carrier phase of each phase winding to obtain the switching drive signal of each full-bridge inverter.

2. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting as described in claim 1, characterized in that, In step S2, the carrier phase difference between each set of three-phase windings in the N sets of three-phase windings is symmetrical.

3. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shift as described in claim 2, characterized in that, If N=4, then the carrier phase differences between each set of three-phase windings are 0 and θ, respectively. c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, and θ, respectively. c θ c ; If N=6, then the carrier phase difference between each set of three-phase windings is 0, θ, and so on. c , 0, θ c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, 0, and θ, respectively. c θ c θ c ; If N=8, then the carrier phase differences between each set of three-phase windings are 0 and θ, respectively. c , 0, θ c , 0, θ c , 0, θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, 0, 0, θ respectively. c θ c θ c θ c Alternatively, the carrier phase differences between each set of three-phase windings are 0, 0, and θ, respectively. c θ c , 0, 0, θ c θ c ; Where, θ c The carrier phase difference is non-zero.

4. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting as described in any one of claims 1 to 3, characterized in that, Step S3 includes: Fix the carrier phase of one phase, and iterate through the carrier phases of the other two phases; For each carrier phase combination traversed, while keeping the carrier phase difference between each set of three-phase windings constant, the corresponding high-frequency magnetic field is calculated, and the main oscillating high-frequency magnetic field is extracted. The carrier phase combination with the smallest amplitude of the high-frequency magnetic field that mainly causes vibration is taken as the optimal carrier phase combination within the set, and the corresponding carrier phase difference is determined as the carrier phase difference between the windings within each set of three-phase windings.

5. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting as described in any one of claims 1 to 3, characterized in that, The motor modes and their corresponding natural frequencies were obtained by impact testing or finite element simulation.

6. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting as described in any one of claims 1 to 3, characterized in that, The formula for calculating high-frequency electromagnetic force is: ； in, For even numbers greater than or equal to 2, It is an odd number; Indicates the angle of space machinery. Indicates time; This represents the radial permeability constant of the air gap. Indicates the permeability of free space; express Step rotor magnetic field, This represents the number of rotor pole pairs; The fundamental angular frequency, Indicates the initial phase of the fundamental magnetic field; Indicates that the frequency in the winding is The high-frequency magnetomotive force generated by the harmonic current. This is the carrier angular frequency.

7. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shifting as described in claim 6, characterized in that, High-frequency magnetomotive force The expression is: ； in, Indicates the winding sequence number. Indicates the first The frequency in the phase winding is Harmonic currents, Indicates the first The winding function of the phase winding.

8. The high-frequency vibration suppression system for multi-phase three-phase permanent magnet synchronous motors based on full-bridge carrier phase shift as described in claim 7, characterized in that, Harmonic current and winding function The expressions are as follows: ； ； in, The amplitude of the harmonic current. For the first Phase carrier phase, For the first Phase of fundamental wave, The initial phase angle; This indicates the order of the Fourier decomposition of the winding function. For the corresponding amplitude coefficient, The initial phase angle, This represents the spatial phase difference between two adjacent phase windings.

9. A multi-phase three-phase permanent magnet synchronous motor system, characterized in that, include: A multi-phase permanent magnet synchronous motor and a high-frequency vibration suppression system for a multi-phase permanent magnet synchronous motor based on full-bridge carrier phase shift as described in any one of claims 1 to 8; The multi-phase three-phase permanent magnet synchronous motor includes N sets of three-phase windings arranged sequentially along the stator circumference, where N is an even number and the windings are concentrated windings.

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