A motor offset angle identification method and device and a storage medium

Abstract

Embodiments of the present application disclose a motor offset angle identification method and device and a storage medium, wherein the method comprises: applying three groups of excitation voltage vectors to a stator of a motor, the excitation voltage vectors being used to rotate a rotor of the motor, and the three groups of excitation voltage vectors having different phase angles; obtaining encoder values under the three groups of excitation voltage vectors, the three groups of excitation voltage vectors including a zero-degree voltage vector; determining the encoder value under the zero-degree voltage vector as a target offset angle; and in the case that a rotation range of the motor is at a counting switching boundary of the encoder, determining a relationship between a rotation direction of the motor and a counting direction of the encoder according to the encoder values under the three groups of excitation voltage vectors, so that the motor offset angle can be quickly and accurately identified, and the relationship between the rotation direction of the motor and the counting direction of the encoder is determined to adapt to any line sequence of a motor power line.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric motor, and particularly relates to a motor offset angle identification method and device and a storage medium. BACKGROUND

[0002] With the development of science and technology, robots, numerical control machine tools, aerospace, advanced manufacturing equipment and other fields have put forward higher and higher requirements for modern electric servo systems, and permanent magnet synchronous motor servo driving technology has gradually become the mainstream of electric servo systems due to its small size, low energy consumption and good control performance. The precision of the electric servo system is very high for the field orientation of the permanent magnet synchronous motor, and the magnetic field of the permanent magnet synchronous motor must be controlled to make the electric servo system have high precision to meet the actual needs.

[0003] At present, it is usually necessary to identify the offset angle of the permanent magnet synchronous motor by using the current injection D-axis method, which has the problems of slow rotation speed and long identification period. SUMMARY

[0004] The present application provides a motor offset angle identification method, device and storage medium.

[0005] In a first aspect, a motor offset angle identification method is provided, and the method comprises:

[0006] Three groups of excitation voltage vectors are applied to the stator of the motor, the excitation voltage vectors are used to rotate the rotor of the motor, and the phase angles of the three groups of excitation voltage vectors are different;

[0007] The encoder values under the three groups of excitation voltage vectors are obtained, and the three groups of excitation voltage vectors include a zero-degree voltage vector;

[0008] The encoder value under the zero-degree voltage vector is determined as a target offset angle;

[0009] In the case that the rotation range of the motor is at the counting switching boundary of the encoder, the relationship between the rotation direction of the motor and the counting direction of the encoder is determined according to the encoder values under the three groups of excitation voltage vectors.

[0010] In an optional embodiment, the method further comprises:

[0011] The running angle of the motor is determined based on the encoder values under the three groups of excitation voltage vectors;

[0012] The running angle of the motor is compared with a reference angle range to determine whether the rotation range of the motor is at the counting switching boundary of the encoder.

[0013] In an alternative embodiment, before determining whether the rotation range of the motor is before the counting switching boundary of the encoder, the method further comprises:

[0014] According to the running angle of the motor and the phase angle of the three sets of excitation voltage vectors, determining whether the rotation range of the motor is sufficient;

[0015] If the rotation range of the motor is insufficient, increasing the amplitude of the excitation voltage vectors until the rotation range of the motor is sufficient.

[0016] In an alternative embodiment, the determining the relationship between the rotation direction of the motor and the counting direction of the encoder according to the encoder values under the three sets of excitation voltage vectors comprises:

[0017] By comparing the size relationship between the encoder values under the three sets of excitation voltage vectors, determining the relationship between the rotation direction of the motor and the counting direction of the encoder as a same direction relationship or a reverse direction relationship.

[0018] In an alternative embodiment, after determining the relationship between the rotation direction of the motor and the counting direction of the encoder, the method further comprises:

[0019] Obtaining the real-time detection value of the encoder;

[0020] According to the real-time detection value of the encoder, the target offset angle, and the relationship between the rotation direction of the motor and the counting direction of the encoder, calculating the electrical angle of the motor.

[0021] In an alternative embodiment, the method further comprises:

[0022] According to the relationship between the rotation direction of the motor and the counting direction of the encoder, determining the current loop output expression of the motor;

[0023] According to the current loop output expression of the motor, calculating the current loop output result when the motor is running.

[0024] In an alternative embodiment, the method further comprises:

[0025] According to the resistance parameter of the motor and the bus voltage of the driver, determining an initial voltage instruction;

[0026] The applying three sets of excitation voltage vectors to the stator of the motor comprises:

[0027] Based on the initial voltage instruction, applying the three sets of excitation voltage vectors to the stator of the motor.

[0028] In one optional implementation, determining the initial voltage command based on the motor's resistance parameters and the driver bus voltage includes:

[0029] The motor current is calculated based on the motor's resistance parameters and the driver bus voltage.

[0030] Based on the preset correspondence between starting torque and current, the starting torque corresponding to the current of the motor is determined, and the voltage of the initial voltage command is determined to be the voltage corresponding to the starting torque.

[0031] Secondly, a motor offset angle identification device is provided, comprising:

[0032] The processing module is used to apply three sets of excitation voltage vectors to the stator of the motor, the excitation voltage vectors being used to rotate the rotor of the motor, and the three sets of excitation voltage vectors having different phase angles;

[0033] The acquisition module is used to acquire encoder values ​​under the three sets of excitation voltage vectors, including the zero-degree voltage vector.

[0034] The determination module is used to determine the encoder value under the zero-degree voltage vector as the target offset angle;

[0035] The determining module is further configured to, when the rotation range of the motor is within the counting switching boundary of the encoder, determine the relationship between the rotation direction of the motor and the counting direction of the encoder based on the encoder values ​​under the three sets of excitation voltage vectors.

[0036] Thirdly, a computer storage medium is provided, which stores one or more instructions adapted for loading by a processor and executing the steps of the first aspect and any possible implementation thereof.

[0037] This application provides a method for identifying motor offset angle. It involves applying three sets of excitation voltage vectors to the stator of a motor, each set causing the rotor to rotate. These three sets of excitation voltage vectors have different phase angles. The method obtains encoder values ​​under these three sets of excitation voltage vectors, including a zero-degree voltage vector. The encoder value under the zero-degree voltage vector is determined as the target offset angle. When the motor's rotation range falls within the encoder's counting switching boundary, the relationship between the motor's rotation direction and the encoder's counting direction is determined based on the encoder values ​​under the three sets of excitation voltage vectors. This method allows for rapid and accurate identification of the motor offset angle. Furthermore, by determining the relationship between the motor's rotation direction and the encoder's counting direction, it can adapt to offset angle identification for any sequence of motor power lines. Attached Figure Description

[0038] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the background art, the drawings needed to be used in the embodiments of the present application or the background art will be described below.

[0039] Figure 1 A flowchart of a motor offset angle identification method provided by the embodiments of the present application;

[0040] Figure 2 A flowchart of a motor operation calculation method provided by the embodiments of the present application;

[0041] Figure 3 A structural diagram of a motor offset angle identification device provided by the embodiments of the present application. DETAILED DESCRIPTION

[0042] In order for those skilled in the art to better understand the technical solutions of the present application, the technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0043] The terms "first", "second", and the like in the specification of the present application and the above-mentioned drawings are used to distinguish different objects, not to describe a specific order. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units is not limited to the listed steps or units, but can optionally include steps or units not listed, or can optionally include other steps or units inherent to the process, method, product or device.

[0044] In this document, the term "embodiment" means that the specific features, structures or characteristics described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor is it independent or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0045] First, the basic principles involved in the motor offset angle identification method in the embodiments of the present application are introduced as follows:

[0046] The motor rotor is located at any position in the DQ coordinate system. An excitation voltage vector of a certain magnitude and direction is applied to the motor stator in the DQ coordinate system, causing the stator to generate a constant magnetic field that interacts with the rotor's magnetic field. This forces the motor rotor to rotate until the two magnetic flux linkages are aligned, i.e., the rotor coincides with the applied voltage vector. If the applied voltage vector angle is zero, i.e., the applied voltage vector is aligned with the D-axis in the DQ coordinate system, the motor rotor will rotate to a stop along the D-axis. At this point, the value from the photoelectric encoder can be read; this value is the offset angle θoffect.

[0047] The embodiments of this application are described below with reference to the accompanying drawings.

[0048] Please see Figure 1 , Figure 1 This is a flowchart illustrating a motor offset angle identification method provided in an embodiment of this application. Figure 1 As shown, the method includes:

[0049] 101. Three sets of excitation voltage vectors are applied to the stator of the motor. The excitation voltage vectors are used to make the rotor of the motor rotate. The phase angles of the three sets of excitation voltage vectors are different.

[0050] Specifically, based on the aforementioned basic principles, the identification process in this application embodiment can apply three sets of excitation voltage vectors to the stator of the motor, causing the rotor of the motor to rotate. The phase angle of the voltage vectors can be selected and set as needed. For example, the phase angles of the three sets of excitation voltage vectors are -30°, 0°, and 30°, respectively. This application embodiment does not impose any restrictions on this. Among them, a zero-degree voltage vector, that is, a voltage vector with a phase angle of 0°, needs to be set to measure the target offset angle.

[0051] In an optional implementation, the method further includes:

[0052] Based on the resistance parameters of the motor and the driver bus voltage, determine the initial voltage command;

[0053] The above applies three sets of excitation voltage vectors to the stator of the motor, including:

[0054] Based on the initial voltage command mentioned above, the three sets of excitation voltage vectors are applied to the stator of the motor.

[0055] Specifically, an appropriate initial voltage command can be selected as needed to provide the excitation voltage vector. Optionally, the aforementioned initial voltage command can be set with a ramp, that is, the voltage is adjusted gradually to prevent motor surging.

[0056] Further optionally, determining the initial voltage command based on the motor's resistance parameters and the driver bus voltage includes:

[0057] Calculate the current of the motor based on the resistance parameters of the motor and the bus voltage of the driver.

[0058] Based on the preset correspondence between starting torque and current, the starting torque corresponding to the current of the motor is determined, and the voltage of the initial voltage command is determined to be the voltage corresponding to the starting torque.

[0059] Specifically, an appropriate initial voltage command can be selected based on the resistance parameters of the controlled object's motor and the driver bus voltage. In this embodiment, a preset correspondence between starting torque and current can be set as needed. After calculating the motor current based on the motor's resistance parameters and the driver bus voltage, the starting torque corresponding to the current of the current motor can be determined based on the preset correspondence between starting torque and current, and thus the corresponding voltage can be determined.

[0060] In this application, torque is directly proportional to current. Given the bus voltage and motor phase resistance, the duty cycle can be adjusted to control the injected motor voltage. The injected motor current can be calculated using I=U / R; the set motor torque can be calculated using Toqre=Kt*I. Setting an appropriate starting torque can prevent motor slippage and improve test accuracy. In this embodiment, the identification process can continuously adjust the injected voltage to adapt to test requirements under different loads.

[0061] 102. Obtain the encoder values ​​under the above three sets of excitation voltage vectors, including the zero-degree voltage vector.

[0062] Specifically, after injecting the excitation voltage vector, the encoder can remain stationary for a preset time, such as 0.25 seconds, until the motor stabilizes and stops moving. The current encoder value is then recorded. Assume the identification process involves three sets of voltage vectors with phase angles of -30°, 0°, and 30°, respectively. At this point, the maximum rotation range of the motor is 60 electrical degrees.

[0063] 103. Determine the encoder value under the zero-degree voltage vector as the target offset angle.

[0064] By injecting a 0° voltage vector using the method described above, the corresponding encoder value is recorded as the target offset angle. For example, the recorded value is shown above. That is, the offset angle θ offect In this embodiment of the application, to ensure the accuracy of the results, multiple measurements can be configured to calculate the average value.

[0065] 104. When the rotation range of the motor is within the counting switching boundary of the encoder, the relationship between the rotation direction of the motor and the counting direction of the encoder is determined based on the encoder values ​​under the three sets of excitation voltage vectors.

[0066] The power line sequence of a motor affects its rotation direction. In this embodiment, under any power line sequence, the relationship between the motor's rotation direction and the encoder's counting direction is determined. Then, during normal motor operation, the electrical angle is acquired in real time and corrected at the current loop output terminal, thus achieving any power line sequence.

[0067] Specifically, it can be determined whether the motor's rotation range is within the encoder's counting switching boundary, and the relationship between the motor's rotation direction and the encoder's counting direction can be determined by analyzing the encoder values ​​under the three sets of excitation voltage vectors.

[0068] In an optional implementation, the method further includes:

[0069] The operating angle of the motor is determined based on the encoder values ​​under three sets of excitation voltage vectors.

[0070] By comparing the operating angle of the motor with the reference angle range, it is determined whether the rotation range of the motor is within the counting switching boundary of the encoder.

[0071] The understanding of the encoder's counting switching boundary can be as follows: if the motor's rotation range is exactly at the encoder's operating boundary, i.e., the switching point between the maximum value and zero, the calculated operating angle Δθ = △θ = encoder single-turn value - △θ.

[0072] Specifically, let the encoder values ​​recorded under the three sets of excitation voltage vectors be as follows: , , The actual operating angle of the motor is Δθ = The above reference angle range can be set as needed. If the motor's operating angle is within the reference angle range, it can be determined that the motor's rotation range is within the encoder's counting switching boundary.

[0073] For example, if the motor's operating angle Δθ is greater than 5 / 6*60=50° and less than 7 / 6*60=70°, the reference angle range is 50°~70°. Then, the motor's rotation range is considered to be within the counting switching boundary (within the boundary range), and the encoder counting and motor rotation direction (rotation direction) judgment can be entered to match any motor power line wiring method.

[0074] In an optional implementation, before determining whether the rotation range of the motor is within the encoder's counting switching boundary, the method further includes:

[0075] Based on the operating angle of the motor and the phase angle of the three sets of excitation voltage vectors, determine whether the rotation range of the motor is sufficient.

[0076] If the rotation range of the motor is insufficient, increase the amplitude of the excitation voltage vector until the rotation range of the motor is sufficient.

[0077] Specifically, given three sets of excitation voltage vectors, the motor rotates, and we can determine whether the motor's rotation range is sufficient. The desired outcome is that the motor's operating angle (actual) reaches its maximum rotation range, corresponding to the phase angle of the excitation voltage vectors. For example, if the phase angles of the three voltage vectors are -30°, 0°, and 30°, the maximum rotation range of the motor is 30° - (-30°) = 60°; and the actual operating angle of the motor, Δθ = ... The actual operating angle is not necessarily equal to the maximum rotation range of the motor. Due to various factors, the actual operating angle may be less than the maximum rotation range.

[0078] Therefore, to avoid the motor's actual rotation range being too small, the maximum rotation range of the motor can be determined first based on the phase angles of the three sets of excitation voltage vectors, and then the difference between the motor's operating angle and its maximum rotation range can be judged. For example, it can be determined whether the difference between the motor's operating angle and its maximum rotation range is within a preset difference; if so, the motor's rotation range is sufficient; otherwise, it indicates that the motor's rotation range is insufficient.

[0079] Based on the operating angle of the motor and the phase angle of the three sets of excitation voltage vectors mentioned above.

[0080] If the motor's rotation range is insufficient but does not exceed the maximum voltage vector amplitude, the voltage vector amplitude can be automatically increased until the motor reaches a sufficient rotation range or the process exits after a certain time. This method is particularly suitable for applications involving robotic arms under load, enabling more stable motor rotation and recognition processes.

[0081] In an optional implementation, step 104 includes:

[0082] By comparing the magnitudes of the encoder values ​​under the three sets of excitation voltage vectors, it is determined whether the rotation direction of the motor and the counting direction of the encoder are in the same direction or opposite.

[0083] Specifically, the relationship between the motor's rotation direction and the encoder's counting direction can be determined as follows:

[0084] like < and < The encoder counting direction is in the same direction as the motor rotation direction;

[0085] like < and < The encoder counting direction is in the same direction as the motor rotation direction;

[0086] like < and < The encoder counting direction is in the same direction as the motor rotation direction;

[0087] like < and < The encoder counting direction is opposite to the motor rotation direction;

[0088] like < and < The encoder counting direction is opposite to the motor rotation direction;

[0089] like < and < The encoder counting direction is opposite to the motor rotation direction.

[0090] See also Figure 2 The diagram shows a flowchart of a motor operation calculation method. Figure 2 As shown, after step 104 above, the method further includes:

[0091] 201. Obtain the real-time detection value of the encoder;

[0092] 202. Based on the relationship between the real-time detection value of the encoder, the target offset angle, the rotation direction of the motor and the counting direction of the encoder, calculate the electrical angle of the motor.

[0093] In an optional implementation, the method further includes:

[0094] 203. Based on the relationship between the rotation direction of the motor and the counting direction of the encoder, determine the current loop output expression of the motor.

[0095] 204. Calculate the current loop output result of the motor during operation based on the current loop output expression of the motor described above.

[0096] The motor offset angle identification method in this application embodiment, after determining the target offset angle θoffect and the relationship between the motor's rotation direction and the encoder's counting direction, can calculate the electrical angle and current loop output results in the actual application of the motor.

[0097] Specifically, if the rotation direction of the motor is opposite to the counting direction of the encoder, the electrical angle during normal motor operation is: encoder single-turn value - (encoder real-time detection value - θoffect).

[0098] The current loop output result is Vdq = PI(-ErrIdq);

[0099] If the rotation direction of the motor is the same as the counting direction of the encoder, the electrical angle during normal motor operation is: encoder real-time detection value - θ offect ;

[0100] The current loop output result is Vdq = PI(ErrIdq).

[0101] The motor offset angle identification method in this embodiment applies three sets of excitation voltage vectors to the stator of the motor, which are used to rotate the rotor of the motor. The phase angles of the three sets of excitation voltage vectors are different. The encoder values ​​under the three sets of excitation voltage vectors are obtained, including a zero-degree voltage vector. The encoder value under the zero-degree voltage vector is determined as the target offset angle. When the rotation range of the motor is within the encoder's counting switching boundary, the relationship between the motor's rotation direction and the encoder's counting direction is determined based on the encoder values ​​under the three sets of excitation voltage vectors. This method can quickly and accurately identify the motor offset angle. Furthermore, by determining the relationship between the motor's rotation direction and the encoder's counting direction, it can adapt to offset angle identification for any sequence of motor power lines. Using the method in this embodiment, the single encoder offset angle identification cycle is less than 1 second, improving the identification speed.

[0102] In conventional methods, a given torque and current approach is used, making motor operation susceptible to the influence of the closed-loop regulator. However, the embodiments in this application aim to handle offset angle initialization in the simplest and most efficient way. Given that the parameters of the controlled object are known, an open-loop feedforward approach is adopted. In a macroscopic sense, feedforward control refers to accurately predicting potential future problems by observing conditions, collecting and organizing information, understanding patterns, and predicting trends. It involves taking proactive measures to eliminate potential deviations in their early stages, thus preventing problems from arising at different stages of future development.

[0103] The open-loop feedforward method in this embodiment does not require feedback, unlike the closed-loop feedback system which requires feedback and regulator (such as PID current loop) adjustment. There is no phase lag caused by feedback and regulator, and the processing is fast and stable.

[0104] Based on the description of the foregoing method embodiments, this application also provides a motor offset angle identification device.

[0105] Please seeFigure 3 , Figure 3 This is a schematic diagram of the structure of a motor offset angle identification device provided in an embodiment of this application. Figure 3 As shown, the motor offset angle identification device 300 includes:

[0106] The processing module 310 is used to apply three sets of excitation voltage vectors to the stator of the motor. The excitation voltage vectors are used to make the rotor of the motor rotate. The three sets of excitation voltage vectors have different phase angles.

[0107] The acquisition module 320 is used to acquire encoder values ​​under the above three sets of excitation voltage vectors, including the zero-degree voltage vector.

[0108] The determination module 330 is used to determine the encoder value under the above zero-degree voltage vector as the target offset angle;

[0109] The aforementioned determining module 330 is further configured to, when the rotation range of the motor is within the counting switching boundary of the encoder, determine the relationship between the rotation direction of the motor and the counting direction of the encoder based on the encoder values ​​under the three sets of excitation voltage vectors.

[0110] In one embodiment, the aforementioned motor offset angle identification device 300 can be specifically used to perform, for example... Figure 1 or Figure 2 Any steps in the illustrated embodiments will not be repeated here.

[0111] This application also provides a computer storage medium (Memory), which is a memory device in an electronic device used to store programs and data. It is understood that the computer storage medium here can include both built-in storage media in the electronic device and extended storage media supported by the electronic device. The computer storage medium provides storage space that stores the operating system of the electronic device. Furthermore, the storage space also stores one or more instructions suitable for loading and execution by a processor. These instructions can be one or more computer programs (including program code). It should be noted that the computer storage medium here can be high-speed RAM or non-volatile memory, such as at least one disk storage device; optionally, it can also be at least one computer storage medium located remotely from the aforementioned processor.

[0112] In one embodiment, a processor may load and execute one or more instructions stored in a computer storage medium to implement the corresponding steps in the above embodiments; specifically, one or more instructions in the computer storage medium may be loaded and executed by a processor. Figure 1 orFigure 2 Any steps of the method are not described here.

[0113] Those skilled in the art will clearly understand that, for the sake of convenience and brevity, the specific working process of the above-described device and module can be referred to the corresponding process in the foregoing method embodiments, and will not be repeated here.

[0114] In the embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. For example, the division of modules is merely a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple modules or components may be combined or integrated into another system, or some features may be ignored or not executed. The coupling, direct coupling, or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, apparatuses, or modules, and may be electrical, mechanical, or other forms.

[0115] The modules described as separate components may or may not be physically separate. Similarly, the components shown as modules may or may not be physical modules; they may be located in one place or distributed across multiple network modules. Some or all of the modules can be selected to achieve the purpose of this embodiment, depending on actual needs.

[0116] In the above embodiments, implementation can be achieved, in whole or in part, through software, hardware, firmware, or any combination thereof. When implemented in software, it can be implemented, in whole or in part, as a computer program product. This computer program product includes one or more computer instructions. When these computer program instructions are loaded and executed on a computer, all or part of the flow or function according to the embodiments of this application is generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable device. The computer instructions can be stored in or transmitted through a computer-readable storage medium. The computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium accessible to a computer or a data storage device such as a server or data center that integrates one or more available media. The available media can be read-only memory (ROM), random access memory (RAM), or magnetic media, such as floppy disks, hard disks, magnetic tapes, magnetic disks, or optical media, such as digital versatile discs (DVDs), or semiconductor media, such as solid state disks (SSDs).

Claims

1. A method for identifying motor offset angle, characterized in that, The method includes: Three sets of excitation voltage vectors are applied to the stator of the motor, and the excitation voltage vectors are used to make the rotor of the motor rotate. The three sets of excitation voltage vectors have different phase angles. Obtain encoder values ​​under the three sets of excitation voltage vectors, including the zero-degree voltage vector; The encoder value under the zero-degree voltage vector is determined as the target offset angle; When the rotation range of the motor is within the counting switching boundary of the encoder, the relationship between the rotation direction of the motor and the counting direction of the encoder is determined based on the encoder values ​​under the three sets of excitation voltage vectors, including: The encoder values ​​recorded under the three sets of excitation voltage vectors are as follows: , , By comparing the magnitudes of the encoder values ​​under the three sets of excitation voltage vectors, it is determined whether the rotation direction of the motor and the counting direction of the encoder are in the same direction or opposite directions; the specific judgment is as follows: like < and < The encoder counting direction is in the same direction as the motor rotation direction; like < and < The encoder counting direction is in the same direction as the motor rotation direction; like < and < The encoder counting direction is in the same direction as the motor rotation direction; like < and < The encoder counting direction is opposite to the motor rotation direction; like < and < The encoder counting direction is opposite to the motor rotation direction; like < and < The encoder counting direction is opposite to the motor rotation direction.

2. The motor offset angle identification method according to claim 1, characterized in that, The method further includes: The operating angle of the motor is determined based on encoder values ​​under three sets of excitation voltage vectors; By comparing the operating angle of the motor with the reference angle range, it is determined whether the rotation range of the motor is within the counting switching boundary of the encoder.

3. The motor offset angle identification method according to claim 2, characterized in that, Before determining whether the rotation range of the motor is within the encoder's counting switching boundary, the method further includes: Based on the operating angle of the motor and the phase angle of the three sets of excitation voltage vectors, determine whether the rotation range of the motor is sufficient; If the rotation range of the motor is insufficient, increase the amplitude of the excitation voltage vector until the rotation range of the motor is sufficient.

4. The motor offset angle identification method according to claim 1, characterized in that, After determining the relationship between the rotation direction of the motor and the counting direction of the encoder, the method further includes: Obtain the real-time detection value of the encoder; The electrical angle of the motor is calculated based on the real-time detection value of the encoder, the target offset angle, and the relationship between the rotation direction of the motor and the counting direction of the encoder.

5. The motor offset angle identification method according to claim 4, characterized in that, The method further includes: Based on the relationship between the rotation direction of the motor and the counting direction of the encoder, the current loop output expression of the motor is determined; The current loop output result of the motor during operation is calculated based on the current loop output expression of the motor.

6. The motor offset angle identification method according to claim 1, characterized in that, The method further includes: The initial voltage command is determined based on the resistance parameters of the motor and the driver bus voltage. The application of three sets of excitation voltage vectors to the stator of the motor includes: Based on the initial voltage command, the three sets of excitation voltage vectors are applied to the stator of the motor.

7. The motor offset angle identification method according to claim 6, characterized in that, The step of determining the initial voltage command based on the motor's resistance parameters and the driver bus voltage includes: The motor current is calculated based on the motor's resistance parameters and the driver bus voltage. Based on the preset correspondence between starting torque and current, the starting torque corresponding to the current of the motor is determined, and the voltage of the initial voltage command is determined to be the voltage corresponding to the starting torque.

8. A motor offset angle identification device, characterized in that, The apparatus for performing the method as described in any one of claims 1-7 includes: The processing module is used to apply three sets of excitation voltage vectors to the stator of the motor, the excitation voltage vectors being used to rotate the rotor of the motor, and the three sets of excitation voltage vectors having different phase angles; The acquisition module is used to acquire encoder values ​​under the three sets of excitation voltage vectors, including the zero-degree voltage vector. The determination module is used to determine the encoder value under the zero-degree voltage vector as the target offset angle; The determining module is further configured to, when the rotation range of the motor is within the counting switching boundary of the encoder, determine the relationship between the rotation direction of the motor and the counting direction of the encoder based on the encoder values ​​under the three sets of excitation voltage vectors.

9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, the processor performs the steps of the method as described in any one of claims 1-7.

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