Six-phase permanent magnet synchronous motor control method, device, equipment and storage medium

Abstract

Embodiments of the present application provide a six-phase permanent magnet synchronous motor control method, device, equipment and storage medium. The method comprises: obtaining a current rotor speed of the six-phase permanent magnet synchronous motor, and determining a speed interval of the six-phase permanent magnet synchronous motor, wherein the speed interval comprises: a zero-low-speed zone, a transition zone and a medium-high-speed zone; determining a composite control strategy of a high-frequency square wave injection method and a sliding mode observation method according to a weighted composite algorithm and the speed interval, and controlling the six-phase permanent magnet synchronous motor by using the composite control strategy; and performing weighted processing on estimated results of the high-frequency square wave injection method and the sliding mode observation method according to the weighted composite algorithm, the speed interval and the current rotor speed, and then determining a target rotor angle and a target rotor speed. The embodiments of the present application can meet the performance requirements of the six-phase permanent magnet synchronous motor in various speed ranges, accurately obtain the rotor angle and improve the robustness.

Description

Technical Field

[0001] This application relates to, but is not limited to, the field of motor control technology, and in particular to a control method, apparatus, equipment, and storage medium for a six-phase permanent magnet synchronous motor. Background Technology

[0002] Six-phase permanent magnet synchronous motors have the advantages of high power density and low torque ripple, and are widely used in aerospace, shipbuilding, rail transportation and electric vehicles. In order to achieve high-performance applications of six-phase permanent magnet synchronous motors, vector control technology is required, which has high requirements for accurate acquisition of rotor angle. When using position sensors to detect rotor angle, installing position sensors will increase the system size, increase cost and reduce power density. Moreover, position sensors may fail, resulting in reduced system reliability.

[0003] Currently, the control method for six-phase permanent magnet synchronous motors without position sensors usually adopts the control method of injecting high-frequency cosine signals. However, this method cannot meet the performance requirements of six-phase permanent magnet synchronous motors in various speed ranges, cannot accurately obtain the rotor angle, and requires the introduction of bandpass and low-pass filters. The performance of the filters affects the acquisition of the rotor angle, and the low-pass filter will bring phase lag and amplitude attenuation problems, resulting in poor robustness. Summary of the Invention

[0004] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0005] This application provides a control method, device, equipment, and storage medium for a six-phase permanent magnet synchronous motor, which can meet the performance requirements of the six-phase permanent magnet synchronous motor in various speed ranges, accurately obtain the rotor angle, and improve robustness.

[0006] To achieve the above objectives, a first aspect of this application proposes a control method for a six-phase permanent magnet synchronous motor, comprising: acquiring the current rotor speed of the six-phase permanent magnet synchronous motor; determining a speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero-low speed region, a transition region, and a medium-high speed region; determining a composite control strategy of a high-frequency square wave injection method and a sliding mode observation method based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, wherein the high-frequency square wave injection method is used to estimate a first rotor angle and a first rotor speed, and the sliding mode observation method is used to estimate a second rotor angle and a second rotor speed. Speed; Based on the weighted composite algorithm, the speed range, and the current rotor speed, determine a first weight and a second weight, wherein the first weight corresponding to the zero low-speed zone, the transition zone, and the medium-high speed zone decreases sequentially, and the corresponding second weight increases sequentially; weight the first rotor angle and the first rotor speed according to the first weight, and weight the second rotor angle and the second rotor speed according to the second weight; determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed.

[0007] In some embodiments, the zero-low speed zone refers to the current rotor speed being less than a preset first speed threshold; the transition zone refers to the current rotor speed being greater than or equal to the first speed threshold and less than a preset second speed threshold; the medium-high speed zone refers to the current rotor speed being greater than or equal to the second speed threshold, and the first speed threshold being less than the second speed threshold; in the zero-low speed zone, the first weight is one; in the medium-high speed zone, the first weight is zero; in the transition zone, the formula for calculating the first weight is:

[0008] ,

[0009] in, For the first weight, The current rotor speed, The first speed threshold, The second speed threshold is used; the formula for calculating the target rotor angle is:

[0010] ,

[0011] in, The target rotor angle, The first rotor angle, The second rotor angle, For the first weight, The second weight is used; the formula for calculating the target rotor speed is:

[0012] ,

[0013] in, The target rotor speed, The rotational speed of the first rotor. The second rotor speed is For the first weight, This is the second weight.

[0014] In some embodiments, determining a composite control strategy of high-frequency square wave injection method and sliding mode observation method based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, includes: when the six-phase permanent magnet synchronous motor is in the zero-low speed region, using the high-frequency square wave injection method to control the six-phase permanent magnet synchronous motor; when the six-phase permanent magnet synchronous motor is in the medium-high speed region, using the sliding mode observation method to control the six-phase permanent magnet synchronous motor; when the six-phase permanent magnet synchronous motor is in the transition region, performing weighted composite processing on the high-frequency square wave injection method and the sliding mode observation method according to the preset weighted composite algorithm, and using the weighted composite processing result to control the six-phase permanent magnet synchronous motor.

[0015] In some embodiments, the control steps of the high-frequency square wave injection method include: injecting a high-frequency square wave signal into the direct axis of the first set of windings of the six-phase permanent magnet synchronous motor in the estimated synchronous rotating coordinate system to determine the high-frequency estimated current; determining the target high-frequency current response equation based on the high-frequency estimated current and the high-frequency square wave signal; discretizing the target high-frequency current response equation to determine the current change; determining the first rotor angle error function based on the current change; adjusting the error value output by the first rotor angle error function to zero based on a preset phase-locked loop to obtain the first rotor electrical angular velocity; obtaining the first rotor speed based on the first rotor electrical angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor; and integrating the first rotor electrical angular velocity to obtain the first rotor angle.

[0016] In some embodiments, the expression for the high-frequency square wave signal is:

[0017] ,

[0018] in, The direct-axis high-frequency voltage of the first set of windings. The cross-axis high-frequency voltage of the first set of windings. This refers to the direct-axis high-frequency voltage of the second set of windings of the six-phase permanent magnet synchronous motor. This refers to the quadrature-axis high-frequency voltage of the second set of windings. This refers to the amplitude of the high-frequency square wave signal; the formula for calculating the high-frequency estimated current is:

[0019] ,

[0020] in, Estimate the direct-axis high-frequency current for the first set of windings. For the quadrature-axis high-frequency current estimation of the first set of windings, For the direct-axis high-frequency current estimation of the second set of windings, For the quadrature-axis high-frequency current estimation of the second set of windings, The angle difference between the actual synchronous rotating coordinate system and the estimated synchronous rotating coordinate system of the six-phase permanent magnet synchronous motor;

[0021] ,

[0022] in, It is a direct-axis inductor. It is a quadrature axis inductor. This is the direct-axis mutual inductance between the first set of windings and the second set of windings. The cross-axis mutual inductance between the first set of windings and the second set of windings. for An invertible matrix;

[0023] ;

[0024] The target high-frequency current response equation is:

[0025] ,

[0026] in, , ;

[0027] The formula for calculating the change in current is:

[0028] ,

[0029] in, for Time and The change in current between time points. The time step of the discretization process is... for Moment The first rotor angle error function is:

[0030] ,

[0031] in, For a sign function, when ,but ,when ,but ;when When the value approaches zero, the following equation holds:

[0032] .

[0033] In some embodiments, the control steps of the sliding mode observation method include: determining the winding voltage equations of the first set of windings of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system based on the motor voltage equations and flux linkage equations of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system; determining the generalized voltage equations based on the winding voltage equations, and performing Park transform and inverse transform processing on the symmetricized generalized voltage equations to obtain the current state equations of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system; constructing the sliding mode current observer equations based on the sliding mode observation method and the current state equations; and applying the sliding mode current observer equations to the current state equations. Subtracting the current state equation from the detector equation yields the current error state equation; a sliding mode surface is constructed based on the current error state equation, and an error switching function is determined based on the sliding mode surface; a second rotor angle error function is determined using the error switching function and a preset low-pass filter; based on a preset phase-locked loop, the error value output by the second rotor angle error function is adjusted to zero to obtain the second rotor electrical angular velocity; the second rotor speed is obtained based on the second rotor electrical angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor; the second rotor angle is obtained by integrating and angle compensation processing the second rotor electrical angular velocity.

[0034] In some embodiments, the motor voltage equation is:

[0035] ,

[0036] in, This is the direct-axis voltage of the first set of windings. The quadrature axis voltage of the first set of windings. This refers to the direct-axis voltage of the second set of windings of the six-phase permanent magnet synchronous motor. This refers to the quadrature-axis voltage of the second set of windings. This refers to the direct-axis current of the first set of windings. The quadrature axis current of the first set of windings, This refers to the direct-axis current of the second set of windings. This refers to the quadrature-axis current of the second set of windings. For the direct-axis magnetic flux of the first set of windings, The cross-axis flux linkage of the first set of windings, For the direct-axis flux linkage of the second set of windings, For the cross-axis flux linkage of the second set of windings, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, Let be the resistance of each phase of the winding of the six-phase permanent magnet synchronous motor. The rotor speed of the six-phase permanent magnet synchronous motor;

[0037] The flux linkage equation is:

[0038] ,

[0039] in, It is a direct-axis inductor. It is a quadrature axis inductor. This is the direct-axis mutual inductance between the first set of windings and the second set of windings. The cross-axis mutual inductance between the first set of windings and the second set of windings. The permanent magnet flux linkage of the six-phase permanent magnet synchronous motor is: The winding voltage equation is:

[0040] ,

[0041] in, The differential operator is used; the generalized voltage equation is:

[0042] ,

[0043] in, This refers to the generalized direct-axis voltage of the first set of windings. The generalized quadrature-axis voltage of the first winding is given by: The generalized voltage equation after symmetry processing is:

[0044] ,

[0045] in, For the extended back electromotive force. The current state equation is:

[0046] ,

[0047] in, The equation for the sliding mode current observer is:

[0048] ,

[0049] in, The first set of windings of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system Shaft sliding mode observation current, The first set of windings of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system Shaft sliding mode observation current, for Differentiating with respect to time, for Differentiating with respect to time, For sliding mode gain, It is a saturated continuous function; the current error state equation is:

[0050] ;

[0051] The formula for the sliding surface is: , among which, when for , for , for ;when for , for , for The error switching function is:

[0052] ,

[0053] in, For the two-phase stationary coordinate system Shaft error switching function signal, For the two-phase stationary coordinate system Shaft error switching function signal; the second rotor angle error function is:

[0054] ,

[0055] in, , The cutoff frequency of the low-pass filter is [value]. The parameters are those after the Laplace transform. The rotor angle of the six-phase permanent magnet synchronous motor is [value missing]. The second rotor angle; when At that time, the following equation holds true: .

[0056] To achieve the above objectives, a second aspect of this application provides a control device for a six-phase permanent magnet synchronous motor, comprising: an acquisition unit for acquiring the current rotor speed of the six-phase permanent magnet synchronous motor; a range determination unit for determining a speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero-low speed range, a transition range, and a medium-high speed range; and a control unit for determining a composite control strategy of high-frequency square wave injection method and sliding mode observation method based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, wherein the high-frequency square wave injection method is used to estimate a first rotor angle and a first rotor speed, and the sliding mode observation method is used to estimate a second rotor angle and a second rotor speed. The system includes: a speed and weight determination unit, configured to determine a first weight and a second weight based on the weighted composite algorithm, the speed range, and the current rotor speed, wherein the first weight corresponding to the zero low-speed zone, the transition zone, and the medium-high speed zone decreases sequentially, and the corresponding second weight increases sequentially; a weighting unit, configured to weight the first rotor angle and the first rotor speed according to the first weight, and to weight the second rotor angle and the second rotor speed according to the second weight; and a calculation unit, configured to determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and to determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed.

[0057] To achieve the above objectives, a third aspect of this application provides an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the six-phase permanent magnet synchronous motor control method described in the first aspect.

[0058] To achieve the above objectives, a fourth aspect of the present application provides a storage medium, which is a computer-readable storage medium storing a computer program that, when executed by a processor, implements the six-phase permanent magnet synchronous motor control method described in the first aspect.

[0059] The six-phase permanent magnet synchronous motor control method, apparatus, device, and storage medium proposed in this application include, in embodiments of this application: acquiring the current rotor speed of the six-phase permanent magnet synchronous motor; determining the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero-low speed region, a transition region, and a medium-high speed region; determining a composite control strategy of high-frequency square wave injection method and sliding mode observation method based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, wherein the high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle and the second rotor speed. Speed; Based on the weighted composite algorithm, the speed range, and the current rotor speed, determine a first weight and a second weight, wherein the first weight corresponding to the zero low-speed zone, the transition zone, and the medium-high speed zone decreases sequentially, and the corresponding second weight increases sequentially; weight the first rotor angle and the first rotor speed according to the first weight, and weight the second rotor angle and the second rotor speed according to the second weight; determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed. According to the scheme provided in the embodiments of this application, the speed range of a six-phase permanent magnet synchronous motor is determined, and then a composite control strategy is obtained by using a weighted composite algorithm combined with the high-frequency square wave injection method and the sliding mode observation method. The composite control strategy is then used to control the six-phase permanent magnet synchronous motor. By determining the first weight and the second weight, and by weighting and combining the estimation results of the high-frequency square wave injection method and the sliding mode observation method, the target rotor angle and the target rotor speed are determined. This can meet the performance requirements of the six-phase permanent magnet synchronous motor in various speed ranges, and the rotor estimated angle error is small, thus accurately obtaining the rotor angle. Moreover, the high-frequency square wave injection method does not require the setting of a filter, which can improve robustness.

[0060] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures particularly pointed out in the description, claims and drawings. Attached Figure Description

[0061] The accompanying drawings are used to provide a further understanding of the technical solutions of this application and constitute a part of the specification. They are used together with the embodiments of this application to explain the technical solutions of this application and do not constitute a limitation on the technical solutions of this application.

[0062] Figure 1 This is a flowchart of a six-phase permanent magnet synchronous motor control method applied to a terminal according to an embodiment of this application;

[0063] Figure 2 This is a flowchart of a method for determining a composite control strategy provided in another embodiment of this application;

[0064] Figure 3 This is a flowchart of a control method for a high-frequency square wave injection method provided in another embodiment of this application;

[0065] Figure 4 This is a flowchart of a control method for a sliding mode observation method provided in another embodiment of this application;

[0066] Figure 5 This is a schematic diagram of the actual rotational speed and estimated rotational speed curves provided in another embodiment of this application;

[0067] Figure 6 This is a waveform diagram of the first set of winding ABC phase currents provided in another embodiment of this application;

[0068] Figure 7 This is a waveform diagram of the A and U phase currents corresponding to the first and second sets of windings provided in another embodiment of this application;

[0069] Figure 8 This is a schematic diagram of the actual rotor position and the estimated rotor position provided in another embodiment of this application;

[0070] Figure 9 This is a schematic diagram illustrating the error between the actual rotor position and the estimated rotor position, provided in another embodiment of this application;

[0071] Figure 10 This is a schematic diagram of an injected high-frequency square wave signal provided in another embodiment of this application;

[0072] Figure 11 This is a schematic diagram of a strategy for synchronously rotating coordinate systems provided in another embodiment of this application;

[0073] Figure 12 This is a schematic diagram of a high-frequency square wave injection method provided in another embodiment of this application;

[0074] Figure 13 This is a schematic diagram of the sliding mode observation method provided in another embodiment of this application;

[0075] Figure 14 This is a schematic diagram of the structure of a six-phase permanent magnet synchronous motor control device provided in another embodiment of this application;

[0076] Figure 15 This is a schematic diagram of the hardware structure of an electronic device provided in another embodiment of this application. Detailed Implementation

[0077] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0078] In the description of this application, "several" means one or more, "multiple" means two or more, "greater than", "less than", "exceeding" etc. are understood to exclude the number itself, and "above", "below", "within" etc. are understood to include the number itself.

[0079] It should be noted that although functional modules are divided in the device schematic diagram and a logical order is shown in the flowchart, in some cases, the steps shown or described may be performed in a different order than the module division in the device or the order in the flowchart. The terms "first," "second," etc., in the specification, claims, or the aforementioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0080] Currently, the control method for six-phase permanent magnet synchronous motors without position sensors usually adopts the control method of injecting high-frequency cosine signals. However, this method cannot meet the performance requirements of six-phase permanent magnet synchronous motors in various speed ranges, cannot accurately obtain the rotor angle, and requires the introduction of bandpass and low-pass filters. The performance of the filters affects the acquisition of the rotor angle, and the low-pass filter will bring phase lag and amplitude attenuation problems, resulting in poor robustness.

[0081] To address the issues of inaccurate rotor angle acquisition and poor robustness, this application provides a control method, apparatus, device, and storage medium for a six-phase permanent magnet synchronous motor. The method includes: acquiring the current rotor speed of the six-phase permanent magnet synchronous motor; determining the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero-low speed region, a transition region, and a medium-high speed region; determining a composite control strategy of high-frequency square wave injection and sliding mode observation based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, wherein the high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode... The observation method is used to estimate the second rotor angle and the second rotor speed. Based on the weighted composite algorithm, the speed range, and the current rotor speed, a first weight and a second weight are determined. The first weight decreases sequentially for the zero-low speed region, the transition region, and the medium-high speed region, while the corresponding second weights increase sequentially. The first rotor angle and the first rotor speed are weighted according to the first weight, and the second rotor angle and the second rotor speed are weighted according to the second weight. The target rotor angle is determined based on the weighted first rotor angle and the weighted second rotor angle, and the target rotor speed is determined based on the weighted first rotor speed and the weighted second rotor speed. According to the solution provided in the embodiments of the present invention, by determining the speed range of a six-phase permanent magnet synchronous motor, and then using a weighted composite algorithm, combining the high-frequency square wave injection method and the sliding mode observation method to obtain a composite control strategy, the six-phase permanent magnet synchronous motor is controlled using the composite control strategy. By determining the first weight and the second weight, and performing weighted processing and combination processing on the estimation results of the high-frequency square wave injection method and the sliding mode observation method, the target rotor angle and the target rotor speed are determined. This can meet the performance requirements of the six-phase permanent magnet synchronous motor in various speed ranges, with a small rotor angle estimation error, thereby accurately obtaining the rotor angle. Moreover, the high-frequency square wave injection method does not require the setting of a filter, which can improve robustness.

[0082] The six-phase permanent magnet synchronous motor control method, device, equipment, and storage medium provided in this application are specifically described through the following embodiments. First, the six-phase permanent magnet synchronous motor control method in this application embodiment is described.

[0083] The six-phase permanent magnet synchronous motor control method provided in this application relates to the field of motor control technology. This method can be applied to a terminal, a server, or software running on either a terminal or a server. In some embodiments, the terminal can be a smartphone, tablet, laptop, desktop computer, etc.; the server can be configured as an independent physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server providing basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN, and big data and artificial intelligence platforms; the software can be an application implementing the six-phase permanent magnet synchronous motor control method, but is not limited to the above forms.

[0084] This application can be used in a wide variety of general-purpose or special-purpose computer system environments or configurations. Examples include: personal computers, server computers, handheld or portable devices, tablet devices, multiprocessor systems, microprocessor-based systems, set-top boxes, programmable consumer electronics, network PCs, minicomputers, mainframe computers, and distributed computing environments including any of the above systems or devices. This application can be described in the general context of computer-executable instructions executed by a computer, such as program modules. Generally, program modules include routines, programs, objects, components, data structures, etc., that perform specific tasks or implement specific abstract data types. This application can also be practiced in distributed computing environments where tasks are performed by remote processing devices connected via a communication network. In distributed computing environments, program modules can reside in local and remote computer storage media, including storage devices.

[0085] The embodiments of this application will be further described below with reference to the accompanying drawings.

[0086] like Figure 1 As shown, Figure 1 This is a flowchart illustrating a control method for a six-phase permanent magnet synchronous motor according to an embodiment of this application. The control method includes, but is not limited to, the following steps:

[0087] Step S110: Obtain the current rotor speed of the six-phase permanent magnet synchronous motor;

[0088] Step S120: Determine the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed. The speed range includes: zero low speed range, transition range and medium high speed range.

[0089] Step S130: Based on the preset weighted composite algorithm and speed range, determine the composite control strategy of high-frequency square wave injection method and sliding mode observation method, and use the composite control strategy to control the six-phase permanent magnet synchronous motor. The high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle and the second rotor speed.

[0090] Step S140: Determine the first weight and the second weight according to the weighted composite algorithm, the speed range and the current rotor speed. The first weights corresponding to the zero low speed zone, the transition zone and the medium high speed zone decrease in sequence, and the corresponding second weights increase in sequence.

[0091] Step S150: The first rotor angle and the first rotor speed are weighted according to the first weight, and the second rotor angle and the second rotor speed are weighted according to the second weight.

[0092] Step S160: Determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed.

[0093] Understandably, the speed range is determined based on the current rotor speed, divided into a zero-low speed zone, a transition zone, and a medium-high speed zone. The zero-low speed zone includes both a zero-speed range and a low-speed range, representing the state of the six-phase permanent magnet synchronous motor at a low speed. The medium-high speed zone includes both a medium-speed range and a high-speed range, representing the state of the six-phase permanent magnet synchronous motor at a high speed. The transition zone refers to the state of the six-phase permanent magnet synchronous motor during the transition from the zero-low speed zone to the medium-high speed zone. Based on this, by determining the speed range of the six-phase permanent magnet synchronous motor, a composite control strategy is obtained using a weighted composite algorithm, combining the high-frequency square wave injection method and the sliding mode observation method. This composite control strategy is then used to control the six-phase permanent magnet synchronous motor. By determining the first and second weights and weighting and combining the estimation results from the high-frequency square wave injection method and the sliding mode observation method, the target rotor angle and target rotor speed are determined. This approach meets the performance requirements of the six-phase permanent magnet synchronous motor in each speed range, with a small error in the estimated rotor angle, thus accurately obtaining the rotor angle. Furthermore, the high-frequency square wave injection method does not require a filter, improving robustness.

[0094] It should be noted that the rotor angle can characterize the rotor position, and the rotor position can be determined by the rotor angle.

[0095] In another embodiment, the zero low speed zone refers to the current rotor speed being less than a preset first speed threshold, the transition zone refers to the current rotor speed being greater than or equal to the first speed threshold and less than a preset second speed threshold, and the medium high speed zone refers to the current rotor speed being greater than or equal to the second speed threshold and the first speed threshold being less than the second speed threshold.

[0096] In the zero-speed zone, the first weight is one; in the medium-speed zone, the first weight is zero; in the transition zone, the formula for calculating the first weight is:

[0097] ,in, As the first weight, The current rotor speed, The first speed threshold, The second speed threshold;

[0098] The formula for calculating the target rotor angle is:

[0099] ,in, For the target rotor angle, For the first rotor angle, For the second rotor angle, As the first weight, As the second weight;

[0100] The formula for calculating the target rotor speed is:

[0101] ,in, For the target rotor speed, The first rotor speed, The second rotor speed, As the first weight, It is the second weight.

[0102] Understandably, when At that time, the six-phase permanent magnet synchronous motor is in the zero low-speed region. At that time, the six-phase permanent magnet synchronous motor is in the transition region. The six-phase permanent magnet synchronous motor is located in the medium-to-high speed range; therefore, the formula for calculating the first weight is:

[0103] The second weight is: .

[0104] Additionally, refer to Figure 2 In one embodiment, Figure 1 Step S130 in the illustrated embodiment includes, but is not limited to, the following steps:

[0105] Step S210: When the six-phase permanent magnet synchronous motor is in the zero low speed region, the six-phase permanent magnet synchronous motor is controlled by the high-frequency square wave injection method.

[0106] Step S220: When the six-phase permanent magnet synchronous motor is in the medium-high speed range, the sliding mode observation method is used to control the six-phase permanent magnet synchronous motor.

[0107] Step S230: When the six-phase permanent magnet synchronous motor is in the transition zone, according to the preset weighted composite algorithm, the high-frequency square wave injection method and the sliding mode observation method are weighted compositely processed, and the weighted composite processing result is used to control the six-phase permanent magnet synchronous motor.

[0108] Understandably, using the high-frequency square wave injection method to control the motor in the zero-low speed region can accurately obtain the rotor angle. In the medium-high speed region, the prediction accuracy of the high-frequency square wave injection method decreases. Therefore, using the sliding mode observation method to control the motor can accurately obtain the rotor angle. In the transition region, a weighted composite algorithm is used to perform weighted composite processing of the high-frequency square wave injection method and the sliding mode observation method to achieve a smooth transition in the control process and ensure the accuracy of rotor angle acquisition.

[0109] Additionally, refer to Figure 3 In one embodiment, Figure 1 The control steps of the high-frequency square wave injection method in step S130 of the illustrated embodiment include, but are not limited to, the following steps:

[0110] Step S310: Inject a high-frequency square wave signal into the direct axis of the first set of windings of the six-phase permanent magnet synchronous motor in the estimated synchronous rotating coordinate system to determine the high-frequency estimated current.

[0111] Step S320: Determine the target high-frequency current response equation based on the high-frequency estimated current and the high-frequency square wave signal;

[0112] Step S330: Discretize the target high-frequency current response equation to determine the current change.

[0113] Step S340: Determine the first rotor angle error function based on the change in current;

[0114] Step S350: Based on the preset phase-locked loop, adjust the error value output by the first rotor angle error function to zero to obtain the first rotor electric angular velocity;

[0115] Step S360: Obtain the first rotor speed based on the first rotor electric angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor;

[0116] Step S370: Integrate the first rotor electric angular velocity to obtain the first rotor angle.

[0117] It is understandable that by using the high-frequency square wave injection method to control the six-phase permanent magnet synchronous motor in the zero-low speed region, the rotor angle can be accurately obtained. In the transition region, the high-frequency square wave injection method and the sliding mode observation method are weighted and combined, and the result of the weighted combination is used to control the six-phase permanent magnet synchronous motor, which can accurately obtain the rotor angle.

[0118] In another embodiment, the expression for the high-frequency square wave signal is:

[0119] ,in, For the direct-axis high-frequency voltage of the first set of windings, For the quadrature axis high-frequency voltage of the first set of windings, This refers to the direct-axis high-frequency voltage of the second winding of a six-phase permanent magnet synchronous motor. For the cross-axis high-frequency voltage of the second set of windings, It refers to the amplitude of a high-frequency square wave signal;

[0120] The formula for calculating high-frequency estimated current is:

[0121] ,

[0122] in, For the first set of windings, estimate the direct-axis high-frequency current. For the quadrature-axis high-frequency current estimation of the first set of windings, For estimating the direct-axis high-frequency current of the second winding, For estimating the cross-axis high-frequency current of the second winding, The angle difference between the actual synchronous rotating coordinate system and the estimated synchronous rotating coordinate system of the six-phase permanent magnet synchronous motor;

[0123] ,

[0124] in, It is a direct-axis inductor. It is a quadrature axis inductor. For the direct-axis mutual inductance between the first set of windings and the second set of windings, For the cross-axis mutual inductance between the first set of windings and the second set of windings, for An invertible matrix;

[0125] ;

[0126] The target high-frequency current response equation is:

[0127] ,in, , ;

[0128] The formula for calculating the change in current is:

[0129] ,

[0130] in, for Time and The change in current between moments The time step for discretization. for Moment ;

[0131] The first rotor angle error function is:

[0132] ,

[0133] in, For a sign function, when ,but ,when ,but ;

[0134] when When the value approaches zero, the following equation holds: .

[0135] It is understandable that the frequency of the injected high-frequency signal is much greater than the fundamental frequency of the motor current. Ignoring the impedance voltage and back electromotive force, the current state equation of the six-phase permanent magnet synchronous motor can be obtained as shown in equation (1) below:

[0136] (1),

[0137] The high-frequency square wave is injected onto the estimated coordinate axes, which requires first defining an estimated synchronous rotating coordinate system. , This is the actual synchronous rotating coordinate system of a six-phase permanent magnet synchronous motor; , For the estimated synchronous rotating coordinate system of a six-phase permanent magnet synchronous motor, define... Let be the angle difference between the actual synchronous rotation coordinate axis and the estimated synchronous rotation coordinate axis. There is a matrix transformation relationship between the estimated synchronous rotation coordinate axis and the actual synchronous rotation coordinate axis, as shown in equation (2):

[0138] (2),

[0139] Substituting the expression for the high-frequency square wave signal into the calculation formula for the high-frequency estimated current, we obtain the high-frequency current response equation, as shown below:

[0140] (3),

[0141] (4),

[0142] (5),

[0143] (6),

[0144] Then, extract the rotor angle information from the high-frequency current response signal. The signal, equations (3) and (5) contain high-frequency components, which are difficult to extract and process. Therefore, information about the signal can be extracted from equation (4). The extraction method for the term is to discretize equation (4) to obtain the change in current, as shown below:

[0145] (7),

[0146] Equation (7) can be expressed as the formula for calculating the change in current mentioned above:

[0147] (8),

[0148] because Since it is a high-frequency term, it is multiplied by The rotor position error function can be obtained, and then the simplified first rotor angle error function can be obtained: ;when Approaching 0, It also tends to 0, estimating that the rotation coordinates will coincide with the actual rotation coordinates, thus achieving... The estimate.

[0149] It should be noted that, through the high-frequency current response equation, it can be determined that the high-frequency square wave injection method takes into account the coupling between the first set of windings and the second set of windings.

[0150] Additionally, refer to Figure 4 In one embodiment, Figure 1 The control steps of the sliding mode observation method in step S130 of the illustrated embodiment include, but are not limited to, the following steps:

[0151] Step S410: Based on the motor voltage equation and flux linkage equation of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system, determine the winding voltage equation of the first set of windings of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system.

[0152] Step S420: Determine the generalized voltage equation based on the winding voltage equation, and perform Park transformation and inverse transformation on the symmetric generalized voltage equation to obtain the current state equation of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system.

[0153] Step S430: Construct the sliding mode current observer equation based on the sliding mode observation method and the current state equation;

[0154] Step S440: Subtract the sliding mode current observer equation from the current state equation to obtain the current error state equation;

[0155] Step S450: Construct a sliding mode surface based on the current error state equation, and determine the error switching function based on the sliding mode surface;

[0156] Step S460: Determine the second rotor angle error function based on the error switching function and the preset low-pass filter;

[0157] Step S470: Based on the preset phase-locked loop, adjust the error value output by the second rotor angle error function to zero to obtain the second rotor electric angular velocity;

[0158] Step S480: Obtain the second rotor speed based on the second rotor electric angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor;

[0159] Step S490: Integrate and compensate the electric angular velocity of the second rotor to obtain the angle of the second rotor.

[0160] It is understandable that by using the sliding mode observation method to control a six-phase permanent magnet synchronous motor in the medium-to-high speed range, the rotor angle can be accurately obtained. In the transition range, the high-frequency square wave injection method and the sliding mode observation method are weighted and combined, and the result of the weighted combination is used to control the six-phase permanent magnet synchronous motor, which can accurately obtain the rotor angle.

[0161] In one embodiment, the motor voltage equation is:

[0162] ,in, This is the direct-axis voltage of the first winding. This is the quadrature axis voltage of the first winding. This refers to the direct-axis voltage of the second winding of a six-phase permanent magnet synchronous motor. This is the quadrature axis voltage of the second winding. For the direct-axis current of the first winding, For the quadrature axis current of the first winding, For the direct-axis current of the second winding, For the quadrature axis current of the second winding, For the first set of windings, the direct-axis flux linkage For the first set of windings, the cross-axis flux linkage For the direct-axis flux linkage of the second set of windings, For the cross-axis flux linkage of the second set of windings, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, The resistance of each phase of the windings of a six-phase permanent magnet synchronous motor. This refers to the rotor speed of a six-phase permanent magnet synchronous motor.

[0163] The flux linkage equation is:

[0164] ,

[0165] in, It is a direct-axis inductor. It is a quadrature axis inductor. For the direct-axis mutual inductance between the first set of windings and the second set of windings, For the cross-axis mutual inductance between the first set of windings and the second set of windings, The permanent magnet flux linkage for a six-phase permanent magnet synchronous motor;

[0166] The winding voltage equation is:

[0167]

[0168] ,in, It is a differential operator;

[0169] The generalized voltage equation is:

[0170] ,in, For the generalized direct-axis voltage of the first winding, This refers to the generalized quadrature-axis voltage of the first winding.

[0171] The generalized voltage equation after symmetry treatment is:

[0172] ,

[0173] in, To extend the back electromotive force, ;

[0174] The current state equation is:

[0175] ,

[0176] in, ;

[0177] The equation for the sliding mode current observer is:

[0178] ,in, The first set of windings of a six-phase permanent magnet synchronous motor in a two-phase stationary coordinate system Shaft sliding mode observation current, The first set of windings of a six-phase permanent magnet synchronous motor in a two-phase stationary coordinate system Shaft sliding mode observation current, for Differentiating with respect to time, for Differentiating with respect to time, For sliding mode gain, It is a saturated continuous function;

[0179] The current error state equation is:

[0180] ;

[0181] The formula for the sliding surface is:

[0182] , among which, when for , for , for ;when for , for , for ;

[0183] The error switching function is:

[0184] ,in, On a two-phase stationary coordinate system Shaft error switching function signal, On a two-phase stationary coordinate system Shaft error switching function signal;

[0185] The second rotor angle error function is:

[0186] ,in, , This is the cutoff frequency of the low-pass filter. The parameters are those after the Laplace transform. This refers to the rotor angle of a six-phase permanent magnet synchronous motor. This is the second rotor angle;

[0187] when At that time, the following equation holds true: .

[0188] It is understandable that a second set of winding coupling terms exists in the winding voltage equation. By moving the coupling terms to the left side of the equation, a generalized voltage equation is obtained. Then, to simplify the design of the sliding mode observer, an extended back EMF is introduced into the generalized voltage equation, resulting in a symmetric generalized voltage equation, thus achieving symmetry of the inductance matrix. A sliding mode current observer is then constructed. Using sliding mode observation theory, the sliding mode current observer equation is constructed, and the sliding surface and sliding gain are selected. Used to adjust the convergence speed to the sliding surface, in order to ensure the convergence speed. The selection of must satisfy the Lyapunov stability theory, therefore, The range of values ​​for is: Then, the error switching function is obtained. When the state variable enters the sliding mode, the following can be obtained:

[0189] (9),

[0190] (10)

[0191] Because of the error switching function signal and It contains back electromotive force and a large number of high-order harmonics, therefore it needs to be low-pass filtered, where the cutoff frequency of the low-pass filter is... :

[0192] (11),

[0193] Finally, the second rotor angle error function is obtained through equation (11):

[0194] when When, it can be simplified to: .

[0195] It should be noted that the above formula shows that the sliding mode observation method takes into account the coupling between the first and second windings, and by decoupling, the interference from the second winding is eliminated.

[0196] Additionally, refer to Figures 5 to 9 , Figure 5 This is a schematic diagram of the actual rotational speed and estimated rotational speed curves provided in another embodiment of this application. Figure 6 This is a waveform diagram of the ABC phase current of the first set of windings provided in another embodiment of this application. Figure 7 This is a schematic diagram of the waveforms of the A and U phase currents corresponding to the first and second sets of windings provided in another embodiment of this application. Figure 8 This is a schematic diagram of the actual rotor position and the estimated rotor position provided in another embodiment of this application. Figure 9This is a schematic diagram showing the error between the actual rotor position and the estimated rotor position provided in another embodiment of this application.

[0197] It is understandable that the six-phase permanent magnet synchronous motor full-speed domain sensorless technology proposed in this application embodiment is used to implement the six-phase permanent magnet synchronous motor control method of this application embodiment, and then the results are obtained through simulation. Figures 5 to 9 The schematic diagram is shown. According to simulation results, when the six-phase permanent magnet synchronous motor operates in the zero-speed region, switching region, and medium-high speed region, the estimated speed can quickly track the actual speed. At the 0.5s load change moment, the angle error change is minimal, and there is virtually no fluctuation in the switching region. The three-phase current waveforms of the first winding of the six-phase motor have a phase difference of 120°, and the corresponding phases A and U current waveforms of the two windings have a phase difference of 30°, which is consistent with the current characteristics of a six-phase motor. The actual rotor position and the estimated rotor position of the six-phase motor are basically coincident, with an error of only ±0.2 rad, which is relatively small. Therefore, the sensorless technology for the full-speed domain of the six-phase permanent magnet synchronous motor in this embodiment is feasible.

[0198] Additionally, refer to Figures 10 to 11 , Figure 10 This is a schematic diagram of injecting a high-frequency square wave signal according to another embodiment of this application. Figure 11 This is a schematic diagram of a strategy for a synchronous rotating coordinate system provided in another embodiment of this application.

[0199] It is understandable that the injected high-frequency signal frequency is half the switching frequency, and its relationship with the PWM carrier frequency is shown in the figure. , , This represents the value of the current at the sampling time. The amplitude of a high-frequency square wave is represented by: Figure 11 It can be seen that, , This is the actual synchronous rotating coordinate system of a six-phase permanent magnet synchronous motor; , Let this be the estimated synchronous rotating coordinate system for a six-phase permanent magnet synchronous motor; define... This represents the angle difference between the actual synchronous rotating coordinate axis and the estimated synchronous rotating coordinate axis.

[0200] Additionally, refer to Figures 12 to 13 , Figure 12 This is a schematic diagram of a high-frequency square wave injection method provided in another embodiment of this application. Figure 13 This is a schematic diagram of the sliding mode observation method provided in another embodiment of this application.

[0201] Understandably, by Figure 12 It can be seen that the control strategy implementation process of the high-frequency square wave injection method does not require a filter.

[0202] It should be noted that by employing the high-frequency square wave injection method, rotor position information can be obtained through current difference without the need for a filter. Since the high-frequency current signal of the high-frequency square wave injection method is close to the switching frequency, the noise caused by the high-frequency square wave signal is reduced, significantly improving the system bandwidth. In the switching zone, a weighted composite control method combining the high-frequency square wave injection method and the sliding mode observation method is used to reduce the estimated angle error. The design process of the high-frequency square wave injection method and the sliding mode observation method takes into account the coupling effect of the six-phase permanent magnet synchronous motor, resulting in a very small rotor estimated angle error.

[0203] Additionally, refer to Figure 14 This application also provides a six-phase permanent magnet synchronous motor control device 1400, comprising:

[0204] The acquisition unit 1410 is used to acquire the current rotor speed of the six-phase permanent magnet synchronous motor;

[0205] The speed range determination unit 1420 is used to determine the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed. The speed range includes: zero low speed range, transition range and medium high speed range.

[0206] The control unit 1430 is used to determine a composite control strategy of high-frequency square wave injection method and sliding mode observation method according to a preset weighted composite algorithm and speed range, and to use the composite control strategy to control the six-phase permanent magnet synchronous motor. The high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle and the second rotor speed.

[0207] The weight determination unit 1440 is used to determine the first weight and the second weight according to the weighted composite algorithm, the speed range and the current rotor speed. The first weight corresponding to the zero low speed zone, the transition zone and the medium high speed zone decreases in sequence, and the corresponding second weight increases in sequence.

[0208] The weighting unit 1450 is used to perform weighting processing on the first rotor angle and the first rotor speed according to the first weight, and to perform weighting processing on the second rotor angle and the second rotor speed according to the second weight.

[0209] The calculation unit 1460 is used to determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and to determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed.

[0210] It is understood that the specific implementation of the six-phase permanent magnet synchronous motor control device 1400 is basically the same as the specific implementation of the above-mentioned six-phase permanent magnet synchronous motor control method, and will not be repeated here.

[0211] Additionally, refer to Figure 15 , Figure 15 The hardware structure of an electronic device according to another embodiment is illustrated. The electronic device includes:

[0212] The processor 1501 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application.

[0213] The memory 1502 can be implemented as a read-only memory (ROM), static storage device, dynamic storage device, or random access memory (RAM). The memory 1502 can store the operating system and other application programs. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 1502 and called by the processor 1501 to execute the six-phase permanent magnet synchronous motor control method of the embodiments of this application, for example, executing the above-described... Figure 1 Method steps S110 to S160, Figure 2 Method steps S210 to S230, Figure 3 Method steps S310 to S370, Figure 4 Method steps S410 to S490;

[0214] The input / output interface 1503 is used to implement information input and output;

[0215] The communication interface 1504 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, Ethernet cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.).

[0216] Bus 1505 transmits information between various components of the device (e.g., processor 1501, memory 1502, input / output interface 1503, and communication interface 1504);

[0217] The processor 1501, memory 1502, input / output interface 1503 and communication interface 1504 are connected to each other within the device via bus 1505.

[0218] This application embodiment also provides a storage medium, which is a computer-readable storage medium for computer-readable storage. The storage medium stores one or more programs, which can be executed by one or more processors to implement the above-described six-phase permanent magnet synchronous motor control method, for example, executing the above-described... Figure 1 Method steps S110 to S160, Figure 2 Method steps S210 to S230, Figure 3 Method steps S310 to S370, Figure 4 Method steps S410 to S490.

[0219] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.

[0220] The six-phase permanent magnet synchronous motor control method, apparatus, device, and storage medium provided in this application embodiment acquire the current rotor speed of the six-phase permanent magnet synchronous motor; determine the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero-low speed region, a transition region, and a medium-high speed region; determine a composite control strategy of high-frequency square wave injection method and sliding mode observation method based on a preset weighted composite algorithm and the speed range, and use the composite control strategy to control the six-phase permanent magnet synchronous motor, wherein the high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle. The first rotor angle and the second rotor speed are determined based on the weighted composite algorithm, the speed range, and the current rotor speed. The first weight and the second weight are determined sequentially for the zero-low speed zone, the transition zone, and the medium-high speed zone, respectively, while the corresponding second weights are determined sequentially. The first rotor angle and the first rotor speed are weighted according to the first weight, and the second rotor angle and the second rotor speed are weighted according to the second weight. The target rotor angle is determined based on the weighted first rotor angle and the weighted second rotor angle, and the target rotor speed is determined based on the weighted first rotor speed and the weighted second rotor speed. Based on this, by determining the speed range of the six-phase permanent magnet synchronous motor, a composite control strategy is obtained by using a weighted composite algorithm combined with the high-frequency square wave injection method and the sliding mode observation method. The composite control strategy is then used to control the six-phase permanent magnet synchronous motor. By determining the first and second weights and performing weighted and combined processing on the estimation results of the high-frequency square wave injection method and the sliding mode observation method, the target rotor angle and the target rotor speed are determined. This approach can meet the performance requirements of the six-phase permanent magnet synchronous motor in various speed ranges, with a small error in the estimated rotor angle, thus accurately obtaining the rotor angle. Moreover, the high-frequency square wave injection method does not require the setting of a filter, which can improve robustness.

[0221] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.

[0222] It will be understood by those skilled in the art that Figures 1 to 4 The technical solutions shown do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.

[0223] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0224] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.

[0225] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0226] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0227] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.

[0228] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0229] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0230] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0231] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.

Claims

1. A control method for a six-phase permanent magnet synchronous motor, characterized in that, include: Obtain the current rotor speed of the six-phase permanent magnet synchronous motor; Based on the current rotor speed, the speed range of the six-phase permanent magnet synchronous motor is determined, wherein the speed range includes: zero low speed range, transition range and medium high speed range; Based on the preset weighted composite algorithm and the speed range, a composite control strategy of high-frequency square wave injection method and sliding mode observation method is determined, and the composite control strategy is used to control the six-phase permanent magnet synchronous motor. The high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle and the second rotor speed. Based on the weighted composite algorithm, the speed range, and the current rotor speed, a first weight and a second weight are determined, wherein the first weight corresponding to the zero low-speed zone, the transition zone, and the medium-high speed zone decreases sequentially, and the corresponding second weight increases sequentially. The first rotor angle and the first rotor speed are weighted according to the first weight, and the second rotor angle and the second rotor speed are weighted according to the second weight. The target rotor angle is determined based on the weighted first rotor angle and the weighted second rotor angle, and the target rotor speed is determined based on the weighted first rotor speed and the weighted second rotor speed. Wherein, the zero low speed zone refers to the current rotor speed being less than a preset first speed threshold, the transition zone refers to the current rotor speed being greater than or equal to the first speed threshold and less than a preset second speed threshold, and the medium high speed zone refers to the current rotor speed being greater than or equal to the second speed threshold, and the first speed threshold being less than the second speed threshold; In the zero-low speed region, the first weight is one; in the medium-high speed region, the first weight is zero; in the transition region, the formula for calculating the first weight is: ， in, For the first weight, The current rotor speed, The first speed threshold, The second speed threshold; The formula for calculating the target rotor angle is: ， in, The target rotor angle, The first rotor angle, The second rotor angle, For the first weight, This is the second weight; The formula for calculating the target rotor speed is: ， in, The target rotor speed, The rotational speed of the first rotor. The second rotor speed is For the first weight, This is the second weight; The step of determining a composite control strategy of high-frequency square wave injection method and sliding mode observation method based on a preset weighted composite algorithm and the speed range, and using the composite control strategy to control the six-phase permanent magnet synchronous motor, includes: When the six-phase permanent magnet synchronous motor is in the zero low speed region, the six-phase permanent magnet synchronous motor is controlled by the high-frequency square wave injection method. When the six-phase permanent magnet synchronous motor is in the medium-high speed range, the sliding mode observation method is used to control the six-phase permanent magnet synchronous motor. When the six-phase permanent magnet synchronous motor is in the transition zone, the high-frequency square wave injection method and the sliding mode observation method are weighted and combined according to the preset weighted composite algorithm, and the six-phase permanent magnet synchronous motor is controlled by the weighted composite processing result.

2. The method according to claim 1, characterized in that, The control steps of the high-frequency square wave injection method include: A high-frequency square wave signal is injected into the direct axis of the first set of windings of the six-phase permanent magnet synchronous motor in the estimated synchronous rotating coordinate system to determine the high-frequency estimated current. Based on the high-frequency estimated current and the high-frequency square wave signal, the target high-frequency current response equation is determined; Discretize the target high-frequency current response equation to determine the current change. The first rotor angle error function is determined based on the current change. Based on a preset phase-locked loop, the error value output by the first rotor angle error function is adjusted to zero to obtain the first rotor electric angular velocity; The first rotor speed is obtained based on the first rotor electric angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor; The first rotor angle is obtained by integrating the first rotor electrical angular velocity.

3. The method according to claim 2, characterized in that, The expression for the high-frequency square wave signal is: ， in, The direct-axis high-frequency voltage of the first set of windings. The cross-axis high-frequency voltage of the first set of windings. This refers to the direct-axis high-frequency voltage of the second set of windings of the six-phase permanent magnet synchronous motor. This refers to the quadrature-axis high-frequency voltage of the second set of windings. This refers to the amplitude of the high-frequency square wave signal; The formula for calculating the high-frequency estimated current is as follows: ， in, Estimate the direct-axis high-frequency current for the first set of windings. For the quadrature-axis high-frequency current estimation of the first set of windings, For the direct-axis high-frequency current estimation of the second set of windings, For the quadrature-axis high-frequency current estimation of the second set of windings, The angle difference between the actual synchronous rotating coordinate system and the estimated synchronous rotating coordinate system of the six-phase permanent magnet synchronous motor; ， in, It is a direct-axis inductor. It is a quadrature axis inductor. This is the direct-axis mutual inductance between the first set of windings and the second set of windings. The cross-axis mutual inductance between the first set of windings and the second set of windings. for An invertible matrix; ； The target high-frequency current response equation is: ， in, , ; The formula for calculating the change in current is: ， in, for Time and The change in current between time points. The time step of the discretization process is... for Moment ; The first rotor angle error function is: ， in, For a sign function, when ,but ,when ,but ; when When the value approaches zero, the following equation holds: 。 4. The method according to claim 1, characterized in that, The control steps of the sliding mode observation method include: Based on the motor voltage equation and flux linkage equation of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system, determine the winding voltage equation of the first set of windings of the six-phase permanent magnet synchronous motor in the synchronous rotating coordinate system. Based on the winding voltage equation, the generalized voltage equation is determined, and the symmetric generalized voltage equation is subjected to Park transformation and inverse transformation to obtain the current state equation of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system. Based on the sliding mode observation method and the current state equation, construct the sliding mode current observer equation; Subtracting the sliding mode current observer equation from the current state equation yields the current error state equation; Construct a sliding mode surface based on the current error state equation, and determine the error switching function based on the sliding mode surface; The second rotor angle error function is determined based on the error switching function and the preset low-pass filter; Based on a preset phase-locked loop, the error value output by the second rotor angle error function is adjusted to zero to obtain the second rotor electric angular velocity; The second rotor speed is obtained based on the second rotor electric angular velocity and the number of pole pairs of the six-phase permanent magnet synchronous motor; The second rotor's electrical angular velocity is integrated and angle-compensated to obtain the second rotor angle.

5. The method according to claim 4, characterized in that, The motor voltage equation is as follows: ， in, This is the direct-axis voltage of the first set of windings. The quadrature axis voltage of the first set of windings. This refers to the direct-axis voltage of the second set of windings of the six-phase permanent magnet synchronous motor. This refers to the quadrature-axis voltage of the second set of windings. This refers to the direct-axis current of the first set of windings. The quadrature axis current of the first set of windings, This refers to the direct-axis current of the second set of windings. This refers to the quadrature-axis current of the second set of windings. For the direct-axis magnetic flux of the first set of windings, The cross-axis flux linkage of the first set of windings, For the direct-axis flux linkage of the second set of windings, For the cross-axis flux linkage of the second set of windings, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, for Differentiating with respect to time, Let be the resistance of each phase of the winding of the six-phase permanent magnet synchronous motor. The rotor speed of the six-phase permanent magnet synchronous motor; The flux linkage equation is: ， in, It is a direct-axis inductor. It is a quadrature axis inductor. This is the direct-axis mutual inductance between the first set of windings and the second set of windings. The cross-axis mutual inductance between the first set of windings and the second set of windings. The permanent magnet flux linkage of the six-phase permanent magnet synchronous motor; The winding voltage equation is as follows: ， in, It is a differential operator; The generalized voltage equation is: ， in, This refers to the generalized direct-axis voltage of the first set of windings. This refers to the generalized quadrature-axis voltage of the first set of windings; The generalized voltage equation after symmetry treatment is as follows: ， in, To extend the back electromotive force, ; The current state equation is: ， in, ; The equation for the sliding mode current observer is: ， in, The first set of windings of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system Shaft sliding mode observation current, The first set of windings of the six-phase permanent magnet synchronous motor in the two-phase stationary coordinate system Shaft sliding mode observation current, for Differentiating with respect to time, for Differentiating with respect to time, For sliding mode gain, It is a saturated continuous function; The current error state equation is: ； The formula for the sliding surface is: ， Among them, when for , for , for ;when for , for , for ; The error switching function is: ， in, For the two-phase stationary coordinate system Shaft error switching function signal, For the two-phase stationary coordinate system Shaft error switching function signal; The second rotor angle error function is: ， in, , The cutoff frequency of the low-pass filter is [value]. The parameters are those after the Laplace transform. The rotor angle of the six-phase permanent magnet synchronous motor is [value missing]. The second rotor angle; when At that time, the following equation holds true: 。 6. A control device for a six-phase permanent magnet synchronous motor, characterized in that, Applied to a terminal, the device is used to implement the six-phase permanent magnet synchronous motor control method as described in any one of claims 1 to 5, the device comprising: The acquisition unit is used to acquire the current rotor speed of the six-phase permanent magnet synchronous motor; The speed range determination unit is used to determine the speed range of the six-phase permanent magnet synchronous motor based on the current rotor speed, wherein the speed range includes: a zero low-speed range, a transition range, and a medium-high speed range; The control unit is used to determine a composite control strategy of high-frequency square wave injection method and sliding mode observation method according to a preset weighted composite algorithm and the speed range, and to control the six-phase permanent magnet synchronous motor using the composite control strategy. The high-frequency square wave injection method is used to estimate the first rotor angle and the first rotor speed, and the sliding mode observation method is used to estimate the second rotor angle and the second rotor speed. The weight determination unit is used to determine a first weight and a second weight based on the weighted composite algorithm, the speed range, and the current rotor speed, wherein the first weight corresponding to the zero low-speed zone, the transition zone, and the medium-high speed zone decreases sequentially, and the corresponding second weight increases sequentially. The weighting unit is used to weight the first rotor angle and the first rotor speed according to the first weight, and to weight the second rotor angle and the second rotor speed according to the second weight. The calculation unit is used to determine the target rotor angle based on the weighted first rotor angle and the weighted second rotor angle, and to determine the target rotor speed based on the weighted first rotor speed and the weighted second rotor speed.

7. An electronic device, characterized in that, The electronic device includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the six-phase permanent magnet synchronous motor control method as described in any one of claims 1 to 5.

8. A storage medium storing a computer program, characterized in that, When the computer program is executed by the processor, it implements the steps of the six-phase permanent magnet synchronous motor control method as described in any one of claims 1 to 5.

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