A resolver zero point calibration method and device

Abstract

The present application provides a resolver zero point calibration method and device, relating to the field of motor technology. The calibration method includes: executing the following control steps for the quadrature axis of the motor: when the motor is in a no-load state, outputting a first control instruction; when the output voltage of the direct axis of the motor is monitored to meet a first condition, outputting a first voltage control instruction; after the rotor position of the motor is stabilized, obtaining a first angle value corresponding to the quadrature axis based on the resolver angle value detected by the resolver sensor; executing the following control steps for the direct axis of the motor: outputting a second control instruction; when the output voltage of the quadrature axis of the motor is monitored to meet a second condition, outputting a second voltage control instruction; after the rotor position of the motor is stabilized, obtaining a second angle value corresponding to the direct axis based on the resolver angle value detected by the resolver sensor; and calibrating the resolver zero point based on the first and second angle values. Through this application, the resolver zero point calibration is achieved.

Description

Technical Field

[0001] The present application relates to the field of motor technology, and more specifically, to a resolver zero point calibration method and device. Background Art

[0002] The resolver position sensor is a key component for obtaining the motor rotor position, and the resolver zero point is a core element in the motor controller calibration. However, the resolver zero point is often inconsistent with the rotor position zero point. Any deviation in the rotor position may cause torque control inaccuracy, degraded current regulator stability, and even cause overcurrent damage to the drive. Existing technologies often rely on advanced algorithms or high braking torque conditions for precise calibration, which places strict requirements on the control algorithm and calibration environment. Summary of the Invention

[0003] In view of this, the purpose of the present application is to provide a resolver zero point calibration method and device, through which the resolver zero point can be quickly and accurately calibrated, thereby improving the calibration efficiency and calibration accuracy.

[0004] In a first aspect, the present application provides a method for zero point calibration of a resolver, the method comprising: executing the following control steps for the quadrature axis of a motor: when the motor is in a no-load state, outputting a first control instruction, the first control instruction comprising a first rotor control instruction for controlling the rotor angle value of the motor and a first current control instruction for controlling the direct axis current value of the motor; when it is monitored that the output voltage of the direct axis of the motor meets a first condition, outputting a first voltage control instruction for controlling the quadrature axis voltage value of the motor; after the rotor position of the motor is stabilized, obtaining a first angle value corresponding to the quadrature axis according to the angle value detected by the resolver sensor; executing the following control steps for the direct axis of the motor: The following control steps: when the motor is in a no-load state, output a second control instruction, the second control instruction including the first rotor control instruction and a second current control instruction for controlling the quadrature-axis current value of the motor; when it is monitored that the output voltage of the quadrature axis of the motor meets the second condition, output a second voltage control instruction for controlling the direct-axis voltage value of the motor; after the rotor position is stable, obtain a second angle value corresponding to the direct axis according to the angle value detected by the resolver sensor; calibrate the resolver zero point of the resolver sensor according to the first angle value and the second angle value so that the resolver zero point corresponds to the rotor position zero point of the motor.

[0005] In one possible implementation, the first rotor control instruction instructs to control the rotor angle value to zero, the first current control instruction instructs to control the direct-axis current value to zero, the first condition instructs the direct-axis voltage output to be a voltage value corresponding to the direct-axis current value of zero, the first voltage control instruction instructs to control the quadrature-axis voltage to be increased, and the first angle value includes a first resolver angle value, wherein the first resolver angle value is obtained by: when the motor is in a no-load state, outputting the first control instruction to fix the direct-axis voltage output to a voltage value corresponding to the direct-axis current value of zero; outputting the first voltage control instruction to increase the quadrature-axis voltage by controlling the quadrature-axis injection current; when monitoring that the quadrature-axis current increases to a first specified current value, outputting a third voltage control instruction for stopping increasing the quadrature-axis voltage, and continuously acquiring angle values ​​detected by the resolver sensor within a preset time period, so as to average all angle values ​​detected within the preset time period to obtain the first resolver angle value; and outputting a fourth voltage control instruction for controlling the quadrature-axis voltage to decrease, so as to decrease the quadrature-axis voltage to zero.

[0006] In one possible embodiment, the first angle value also includes a second resolver angle value, wherein the second resolver angle value is obtained in the following manner: when the motor is in a no-load state, outputting the first control instruction; outputting the first voltage control instruction to increase the quadrature-axis voltage by controlling the quadrature-axis injection current; when monitoring that the quadrature-axis current increases to a second specified current value, outputting the third voltage control instruction, and continuously obtaining the angle value detected by the resolver sensor within the preset time length, so as to average all the angle values ​​detected within the preset time length to obtain the second resolver angle value; and outputting the fourth voltage control instruction to drop the quadrature-axis voltage to zero.

[0007] In one possible implementation, the second current control instruction instructs controlling the quadrature-axis current value to be zero, the second condition instructs the quadrature-axis voltage output to be a voltage value corresponding to the quadrature-axis current value of zero, the second voltage control instruction instructs controlling the direct-axis voltage to be increased, and the second angle value includes a third resolver angle value, wherein the third resolver angle value is obtained in the following manner: when the motor is in a no-load state, outputting the second control instruction to fix the quadrature-axis voltage output to a voltage value corresponding to the quadrature-axis current value of zero; outputting the second voltage control instruction to increase the direct-axis voltage by controlling the direct-axis current to be injected; when monitoring that the direct-axis current increases to a third specified current value, outputting a fifth voltage control instruction for stopping increasing the direct-axis voltage, and continuously obtaining the angle value detected by the resolver sensor within a preset time length, so as to average all the angle values ​​detected within the preset time length to obtain the third resolver angle value; and outputting a sixth voltage control instruction for controlling the direct-axis voltage to decrease, so as to decrease the direct-axis voltage to zero.

[0008] In one possible embodiment, the second angle value also includes a fourth resolver angle value, wherein the fourth resolver angle value is obtained in the following manner: when the motor is in a no-load state, outputting the second control instruction to fix the quadrature-axis voltage output to a voltage value corresponding to the quadrature-axis current value of zero; outputting the second voltage control instruction to increase the direct-axis voltage by controlling the direct-axis current; when monitoring that the direct-axis current increases to a fourth specified current value, outputting the fifth voltage control instruction, and continuously obtaining the angle value detected by the resolver sensor within the preset time length, so as to average all the angle values ​​detected within the preset time length to obtain the fourth resolver angle value; and outputting the sixth voltage control instruction to drop the direct-axis voltage to zero.

[0009] In one possible implementation, the resolver zero point of the resolver sensor is calibrated in the following manner: based on all resolver angle values, an influence of the quadrature-axis current on a changing trend of the resolver angle value is determined, so as to obtain a resolver zero point initial value based on the changing trend; the resolver zero point initial value is input into a closed-loop regulator of the motor to obtain a resolver zero point fine-tuning value, and the resolver zero point fine-tuning value and the resolver zero point initial value are stored, so as to calibrate the resolver zero point based on the resolver zero point initial value and the resolver zero point fine-tuning value.

[0010] In one possible implementation, the resolver zero point initial value is obtained according to the influence of the change trend in the following manner: if the quadrature-axis current increases the resolver angle value, 180 degrees is subtracted from the sum of all resolver angle values, and the result is divided by the number of resolver angle values ​​to obtain the resolver zero point initial value; if the quadrature-axis current decreases the resolver angle value, 180 degrees is added to the sum of all resolver angle values, and the result is divided by the number of resolver angle values ​​to obtain the resolver zero point initial value.

[0011] In one possible implementation, the influence of the quadrature-axis current on the changing trend of the resolver angle value is determined in the following manner: when the first resolver angle value is greater than the third resolver angle value and the second resolver angle value is greater than the fourth resolver angle value, determining that the quadrature-axis current causes the resolver angle value to increase; and when the first resolver angle value is less than the third resolver angle value and the second resolver angle value is less than the fourth resolver angle value, determining that the quadrature-axis current causes the resolver angle value to decrease.

[0012] In one possible embodiment, the resolver zero point fine-tuning value is obtained in the following manner: outputting a third current control instruction for controlling the quadrature-axis current value and the direct-axis current value, and causing the motor to perform current closed-loop regulation, the third current control instruction instructing to control the quadrature-axis current value and the direct-axis current value to be zero; sending a speed instruction to the dynamometer so that the dynamometer drags the motor to run at a constant speed; outputting an instruction for adjusting the direct-axis voltage smoothing filter coefficient to smooth the direct-axis voltage; using the resolver zero point initial value as the initial value of the closed-loop regulator so that the smoothed direct-axis voltage follows the desired direct-axis voltage through the closed-loop regulator, and outputting the resolver zero point fine-tuning value after the closed-loop regulator is stable.

[0013] In a second aspect, the present application provides a resolver zero point calibration device, the device comprising: a first control module, for executing the following control steps for the quadrature axis of the motor: when the motor is in a no-load state, outputting a first control instruction, the first control instruction comprising a first rotor control instruction for controlling the rotor angle value of the motor and a first current control instruction for controlling the direct-axis current value of the motor; when it is monitored that the output voltage of the direct-axis of the motor meets a first condition, outputting a first voltage control instruction for controlling the quadrature axis voltage value of the motor; after the rotor position of the motor is stabilized, the resolver angle value detected by the resolver sensor is used to obtain a first angle value corresponding to the quadrature axis; a second control module, for The direct axis of the motor performs the following control steps: when the motor is in a no-load state, outputting a second control instruction, the second control instruction including the first rotor control instruction and a second current control instruction for controlling the quadrature-axis current value of the motor; when it is monitored that the output voltage of the quadrature-axis of the motor meets the second condition, outputting a second voltage control instruction for controlling the direct-axis voltage value of the motor; after the rotor position is stable, obtaining a second angle value corresponding to the direct axis according to the resolver angle value detected by the resolver sensor; a determination module is used to calibrate the resolver zero point of the resolver sensor according to the first angle value and the second angle value, so that the resolver zero point corresponds to the rotor position zero point of the motor.

[0014] The present application provides a resolver zero point calibration method and device, wherein the method includes: executing the following control steps for the quadrature axis of a motor: when the motor is in a no-load state, outputting a first control instruction; when monitoring that the output voltage of the direct axis of the motor meets a first condition, outputting a first voltage control instruction; after the rotor position of the motor is stabilized, obtaining a first angle value corresponding to the quadrature axis according to the resolver angle value detected by the resolver sensor; executing the following control steps for the direct axis of the motor: outputting a second control instruction; when monitoring that the output voltage of the quadrature axis of the motor meets a second condition, outputting a second voltage control instruction; after the rotor position of the motor is stabilized, obtaining a first angle value corresponding to the direct axis according to the resolver angle value detected by the resolver sensor; and calibrating the resolver zero point according to the first angle value and the second angle value.

[0015] The beneficial effects of the resolver zero point calibration solution of this application are as follows:

[0016] By executing control strategies on the quadrature axis and direct axis of the motor respectively, the zero point of the resolver is quickly located, and calibration is performed based on the two angle values ​​obtained from the quadrature axis and direct axis, thereby improving calibration efficiency and accuracy.

[0017] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, preferred embodiments are given below and described in detail with reference to the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following is a brief introduction to the drawings required for use in the embodiments. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 A flowchart of a resolver zero point calibration method provided in an embodiment of the present application;

[0020] Figure 2 A flow chart for calibrating the zero point of a resolver provided in an embodiment of the present application;

[0021] Figure 3 A flowchart for obtaining a resolver zero point fine-tuning value provided in an embodiment of the present application;

[0022] Figure 4 This is a schematic structural diagram of a resolver zero point calibration device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. The components of the embodiments of the present application generally described and shown in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the application for which protection is claimed, but merely represents the selected embodiments of the present application. Based on the embodiments of the present application, each other embodiment obtained by those skilled in the art without making creative work falls within the scope of protection of the present application.

[0024] First, the application scenarios to which this application is applicable are introduced. This application can be applied to motor technology.

[0025] Vector control, as a core strategy for AC motor control, relies heavily on accurate sensing of the motor's rotor position for its accuracy. Real-time, precise feedback of the rotor position is a prerequisite for efficient and stable torque control. Any deviation in position information will directly impact the performance of the control system, including but not limited to the accuracy of the torque output, the dynamic response and stability of the current regulator, and, in extreme cases, the activation of the driver's overcurrent protection mechanism, leading to equipment damage or system shutdown. As a key sensor for obtaining motor rotor position information, the resolver operates based on electromagnetic induction and can continuously and reliably provide absolute rotor angle information. However, accurately setting the resolver's zero point is a challenge, as the resolver's mechanical zero point often does not coincide with the motor's actual mechanical zero point. Furthermore, under certain conditions, the resolver signal's direction of change may be opposite to the actual direction of rotor rotation, further complicating the interpretation of position information. Accurate calibration of the resolver zero point is a critical step in motor controller parameter setting. Correct zero-point calibration ensures that the control system accurately understands the relationship between the resolver signal and the actual rotor position, and is the basis for achieving high-performance vector control. Currently, methods for calibrating the resolver zero point mainly rely on advanced algorithms or specific test conditions, such as applying a large braking torque to observe the system response. These methods place high demands on the computing power and accuracy of the control algorithm, as well as the stability of the calibration environment.

[0026] Based on this, an embodiment of the present application provides a resolver zero point calibration method and device, which aims to accurately calibrate the motor resolver zero point, and can be simplified to the motor free sliding working condition calibration without dragging the motor.

[0027] See also Figure 1 , Figure 1 This is a flow chart of a resolver zero point calibration method provided in an embodiment of the present application. Figure 1 As shown in , the resolver zero point calibration method provided in the embodiment of the present application includes:

[0028] S101. Execute the following control steps for the quadrature axis of the motor: when the motor is in a no-load state, output a first control instruction; when it is monitored that the output voltage of the direct axis of the motor meets a first condition, output a first voltage control instruction for controlling the quadrature axis voltage value of the motor; after the rotor position of the motor is stabilized, obtain a first angle value corresponding to the quadrature axis based on the angle value detected by the resolver sensor.

[0029] Here, the first control instruction includes a first rotor control instruction for controlling the rotor angle value of the motor and a first current control instruction for controlling the direct-axis current value of the motor. The first rotor control instruction indicates that the rotor angle value is controlled to zero, the first current control instruction indicates that the direct-axis current value is controlled to zero, the first condition indicates that the direct-axis voltage output is a voltage value corresponding to the direct-axis current value of zero, and the first voltage control instruction indicates that the quadrature-axis voltage is controlled to be increased.

[0030] As an example, before calibration, the motor needs to be mechanically disconnected from the dynamometer so that the motor has no external load and can rotate freely. The rotor position angle value used for coordinate transformation in the motor control is switched to a manual value. At the same time, the DQ current regulator is output in voltage accumulation mode, and the voltage is not increased or decreased according to the current feedback value.

[0031] In a preferred example of the present application, the first angle value includes a first resolver angle value and a second resolver angle value, and the first resolver angle value can be obtained in the following manner: when the motor is in a no-load state, a first control instruction is output to fix the direct-axis voltage output to a voltage value corresponding to a direct-axis current value of zero; a first voltage control instruction is output to increase the quadrature-axis voltage by controlling the quadrature-axis injection current; when it is monitored that the quadrature-axis current increases to a first specified current value, a third voltage control instruction is output for stopping the increase of the quadrature-axis voltage, and the angle value detected by the resolver sensor within a preset time length is continuously obtained to average all the angle values ​​detected within the preset time length to obtain the first resolver angle value; a fourth voltage control instruction is output for controlling the quadrature-axis voltage to decrease so that the quadrature-axis voltage drops to zero.

[0032] The process of obtaining the second resolver angle value is the same as described above. When monitoring the quadrature-axis current, the quadrature-axis voltage adjustment is stopped only after it reaches a second specified current value. The second specified current value here can be the same as the first specified current value, in order to enhance the reliability of the first angle value through repeated measurements.

[0033] Here, the first specified current value and the second specified current value may be a fixed multiple of the rated current of the motor, and the preset time length may be set to 2s.

[0034] S102. Execute the following control steps for the direct axis of the motor: when the motor is in a no-load state, output a second control instruction to fix the quadrature-axis voltage output to a voltage value corresponding to a quadrature-axis current value of zero; output a second voltage control instruction to increase the direct-axis voltage by controlling the direct-axis current injection; when monitoring that the direct-axis current increases to a third specified current value, output a fifth voltage control instruction for stopping the increase of the direct-axis voltage, and continuously obtain the angle value detected by the resolver sensor within a preset time length, so as to average all the angle values ​​detected within the preset time length to obtain a third resolver angle value; output a sixth voltage control instruction for controlling the direct-axis voltage to decrease, so as to decrease the direct-axis voltage to zero.

[0035] Here, the second control instruction includes a first rotor control instruction and a second current control instruction for controlling the quadrature-axis current value of the motor, the second current control instruction indicates that the quadrature-axis current value is controlled to be zero, the second condition indicates that the quadrature-axis voltage output is a voltage value corresponding to the quadrature-axis current value of zero, and the second voltage control instruction indicates that the direct-axis voltage is controlled to be increased.

[0036] In a preferred example of the present application, the second angle value includes a third resolution angle value and a fourth resolution angle value.

[0037] Among them, the third resolver angle value is obtained in the following manner: when the motor is in a no-load state, a second control instruction is output to fix the quadrature-axis voltage output to a voltage value corresponding to a quadrature-axis current value of zero; a second voltage control instruction is output to adjust the direct-axis current; the direct-axis current is monitored, and when the direct-axis current rises to a third specified current value, the direct-axis voltage is stopped from being increased, and the resolver angle value detected by the resolver sensor within a preset time length is continuously obtained, so as to average all angle values ​​detected within the preset time length to obtain the third resolver angle value; and a fourth voltage control instruction for changing the direct-axis voltage is output to drop the direct-axis voltage to zero.

[0038] The process of obtaining the fourth resolver angle value is the same as described above. The third specified current value here may be the same as the fourth specified current value, in order to enhance the reliability of the second angle value through repeated measurements.

[0039] For example, if any of all the rotation angle values ​​cross 0° or 360°, the rotation angle values ​​that cross 0° or 360° are recalculated.

[0040] S103: Calibrate the resolver zero point of the resolver sensor according to the first angle value and the second angle value, so that the resolver zero point corresponds to the rotor position zero point of the motor.

[0041] Below through Figure 2 This article introduces the specific process of calibrating the resolver zero point.

[0042] See also Figure 2 , Figure 2 This is a flow chart for calibrating the zero point of a resolver provided in an embodiment of the present application.

[0043] S201. Determine, based on all resolver angle values, the influence of the quadrature-axis current on the variation trend of the resolver angle value, so as to obtain a resolver zero point initial value based on the variation trend influence.

[0044] Here, the resolver zero point initial value can be calculated based on the influence of the quadrature-axis current on the change trend of the resolver angle value.

[0045] If the quadrature-axis current increases the resolver angle value, then the sum of all resolver angle values ​​is subtracted by 180 degrees and divided by the number of resolver angle values ​​to obtain the resolver zero point initial value.

[0046] At this time, the motor rotor position θ can be calculated by formula (1):

[0047] θ=θ sensor -θ0(1)

[0048] where θ sensor is the resolver angle value obtained by the resolver decoding chip, and θ0 is the resolver zero point initial value.

[0049] In a preferred example of the present application, when the first resolver angle value is greater than the third resolver angle value, and the second resolver angle value is greater than the fourth resolver angle value, the quadrature-axis current is determined to increase the resolver angle value.

[0050] If the quadrature-axis current reduces the resolver angle value, then the sum of all resolver angle values ​​is added with 180 degrees and divided by the number of resolver angle values ​​to obtain the resolver zero point initial value.

[0051] At this time, the motor rotor position θ can be calculated by formula (2):

[0052] θ=θ0-θ sensor (2)

[0053] In a preferred example of the present application, when the first resolver angle value is smaller than the third resolver angle value, and the second resolver angle value is smaller than the fourth resolver angle value, the quadrature-axis current is determined to reduce the resolver angle value.

[0054] S202: Input the resolver zero point initial value into the closed-loop regulator of the motor to obtain the resolver zero point fine-tuning value, and store the resolver zero point fine-tuning value and the resolver zero point initial value to calibrate the resolver zero point according to the resolver zero point initial value and the resolver zero point fine-tuning value.

[0055] Below through Figure 3 This article introduces the specific process of obtaining the resolver zero point fine-tuning value.

[0056] See also Figure 3 , Figure 3 This is a flow chart for obtaining a resolver zero point fine-tuning value provided in an embodiment of the present application.

[0057] As an example, before performing resolver zero point calibration, the motor and dynamometer need to be firmly and rigidly connected so that the dynamometer can effectively drive the motor to run at a constant speed. Next, in the motor controller settings, the calculation method for the rotor position angle value θ is input, that is, formula (1) and formula (2) are input into the motor controller. At this time, the DQ current regulator will adopt a standard closed-loop regulation method, abandoning the cumulative output mode and instead adopting the manual setting mode command to ensure the accuracy and controllability of the regulation process.

[0058] S301 , outputting a third current control instruction for controlling the quadrature-axis current value and the direct-axis current value, and causing the motor to perform current closed-loop regulation.

[0059] Here, the third current control instruction instructs to control the quadrature-axis current value and the direct-axis current value to be zero;

[0060] S302: Send a speed command to the dynamometer to make the dynamometer drive the motor to run at a constant speed.

[0061] S303 : Output an instruction for adjusting the direct-axis voltage smoothing filter coefficient to smooth the direct-axis voltage.

[0062] S304: Using the resolver zero point initial value as the initial value of the closed-loop regulator, so that the smoothed direct-axis voltage follows the direct-axis desired voltage through the closed-loop regulator, and outputting the resolver zero point fine-tuning value after the closed-loop regulator is stable.

[0063] Here, the direct-axis desired voltage is a reference signal for magnetic field alignment and is 0. After the output of the closed-loop regulator is stable, the resolver zero point initial value and the resolver zero point fine-tuning value are stored and recorded in the calibration data.

[0064] Based on the same inventive concept, the embodiment of the present application also provides a resolver zero point calibration device corresponding to the resolver zero point calibration method. Since the principle of solving the problem by the device in the embodiment of the present application is similar to the above-mentioned resolver zero point calibration method in the embodiment of the present application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be repeated.

[0065] See also Figure 4 , Figure 4 This is a schematic diagram of the structure of the resolver zero point calibration device provided in the embodiment of the present application. Figure 4 As shown in , the resolver zero point calibration device 400 includes:

[0066] The first control module 401 is configured to execute the following control steps for the quadrature axis of the motor: when the motor is in a no-load state, output a first control instruction, the first control instruction including a first rotor control instruction for controlling a rotor angle value of the motor and a first current control instruction for controlling a direct axis current value of the motor; when it is monitored that an output voltage of the direct axis of the motor satisfies a first condition, output a first voltage control instruction for controlling a quadrature axis voltage value of the motor; after the rotor position of the motor is stabilized, obtain a first angle value corresponding to the quadrature axis according to a resolver angle value detected by a resolver sensor;

[0067] The second control module 402 is used to perform the following control steps for the direct axis of the motor: when the motor is in a no-load state, output a second control instruction, the second control instruction including the first rotor control instruction and a second current control instruction for controlling the quadrature axis current value of the motor; when it is monitored that the output voltage of the quadrature axis of the motor meets the second condition, output a second voltage control instruction for controlling the direct axis voltage value; after the rotor position of the motor is stabilized, the first angle corresponding to the direct axis is obtained according to the resolver angle value detected by the resolver sensor.

[0068] The determination module 403 is configured to determine a resolver zero point of the resolver sensor according to the first angle value and the second angle value, so that the resolver zero point corresponds to a rotor position zero point of the motor.

[0069] Those skilled in the art will clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0070] In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. The device embodiments described above are merely schematic. For example, the division of the units is merely a logical function division. There may be other division methods in actual implementation. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interface, indirect coupling or communication connection of devices or units, which may be electrical, mechanical or other forms.

[0071] The units described as separate components may or may not be physically separate, and 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 these units may be selected to achieve the purpose of this embodiment according to actual needs.

[0072] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit.

[0073] If the functions are implemented in the form of software functional units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium that is executable by a processor. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or the part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for enabling a computer device (which can be a personal computer, server, or network device, etc.) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes various media that can store program code, such as a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk.

[0074] Finally, it should be noted that the above-described embodiments are only specific implementation methods of the present application, which are used to illustrate the technical solutions of the present application, rather than to limit them. The scope of protection of the present application is not limited thereto. Although the present application has been described in detail with reference to the above-mentioned embodiments, those skilled in the art should understand that any person skilled in the art can modify or easily conceive of changes to the technical solutions described in the above-mentioned embodiments within the technical scope disclosed in the present application, or perform equivalent replacements for some of the technical features thereof. These modifications, changes, or replacements do not deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A resolver zero point calibration method, characterized in that: The method comprises: The following control steps are performed for the quadrature axis of the motor: when the motor is in a no-load state, outputting a first control instruction, the first control instruction including a first rotor control instruction for controlling a rotor angle value of the motor and a first current control instruction for controlling a direct axis current value of the motor; when it is monitored that an output voltage of the direct axis of the motor satisfies a first condition, outputting a first voltage control instruction for controlling a quadrature axis voltage value of the motor; after the rotor position of the motor is stabilized, obtaining a first angle value corresponding to the quadrature axis according to an angle value detected by a resolver sensor; The following control steps are performed for the direct axis of the motor: when the motor is in a no-load state, a second control instruction is output, the second control instruction including the first rotor control instruction and a second current control instruction for controlling the quadrature axis current value of the motor; when it is monitored that the output voltage of the quadrature axis of the motor meets a second condition, a second voltage control instruction for controlling the direct axis voltage value of the motor is output; after the rotor position is stabilized, a second angle value corresponding to the direct axis is obtained according to the angle value detected by the resolver sensor; Calibrate the resolver zero point of the resolver sensor according to the first angle value and the second angle value so that the resolver zero point corresponds to the rotor position zero point of the motor; The resolver zero point of the resolver sensor is calibrated in the following manner: Determining, based on the first angle value and the second angle value, an influence of the quadrature-axis current on a variation trend of the angle value, so as to obtain a resolver zero point initial value based on the influence of the variation trend; The resolver zero point initial value is input into a closed-loop regulator of the motor to obtain a resolver zero point fine-tuning value, and the resolver zero point fine-tuning value and the resolver zero point initial value are stored to calibrate the resolver zero point according to the resolver zero point initial value and the resolver zero point fine-tuning value.

2. The method according to claim 1, characterized in that The first rotor control instruction instructs to control the rotor angle value to zero, the first current control instruction instructs to control the direct-axis current value to zero, the first condition instructs the direct-axis voltage output to be a voltage value corresponding to the direct-axis current value being zero, the first voltage control instruction instructs to control to increase the quadrature-axis voltage, and the first angle value includes a first resolver angle value. The first rotation angle value is obtained by: When the motor is in a no-load state, outputting the first control instruction to fix the direct-axis voltage output to a voltage value corresponding to zero direct-axis current value; Outputting the first voltage control instruction to increase the quadrature-axis voltage by controlling so as to inject the quadrature-axis current; When it is monitored that the quadrature-axis current increases to a first specified current value, outputting a third voltage control instruction for stopping increasing the quadrature-axis voltage, and continuously acquiring angle values ​​detected by the resolver sensor within a preset time period, so as to average all angle values ​​detected within the preset time period to obtain the first resolver angle value; A fourth voltage control instruction for controlling the quadrature-axis voltage to decrease is output, so that the quadrature-axis voltage decreases to zero.

3. The method according to claim 2, characterized in that The first angle value also includes a second rotation angle value, The second rotation angle value is obtained by: When the motor is in a no-load state, outputting the first control instruction; Outputting the first voltage control instruction to increase the quadrature-axis voltage by controlling so as to inject the quadrature-axis current; When it is monitored that the quadrature-axis current increases to a second specified current value, the third voltage control instruction is outputted, and the angle value detected by the resolver sensor within the preset time period is continuously acquired, so as to average all the angle values ​​detected within the preset time period to obtain the second resolver angle value; The fourth voltage control instruction is output to reduce the quadrature-axis voltage to zero.

4. The method according to claim 3, characterized in that The second current control instruction instructs to control the quadrature-axis current value to be zero, the second condition instructs the quadrature-axis voltage output to be a voltage value corresponding to the quadrature-axis current value being zero, the second voltage control instruction instructs to control to increase the direct-axis voltage, and the second angle value includes a third resolver angle value. The third rotation angle value is obtained by: When the motor is in a no-load state, outputting the second control instruction to fix the quadrature-axis voltage output to a voltage value corresponding to zero quadrature-axis current value; outputting the second voltage control instruction to increase the direct-axis voltage by controlling the direct-axis voltage so as to inject the direct-axis current; When monitoring that the direct-axis current increases to a third specified current value, outputting a fifth voltage control instruction for stopping increasing the direct-axis voltage, and continuously acquiring angle values ​​detected by the resolver sensor within a preset time period, so as to average all angle values ​​detected within the preset time period to obtain the third resolver angle value; A sixth voltage control instruction for controlling the direct-axis voltage to decrease is output, so that the direct-axis voltage decreases to zero.

5. The method according to claim 4, characterized in that The second angle value also includes a fourth rotation angle value, The fourth rotation angle value is obtained by: When the motor is in a no-load state, outputting the second control instruction to fix the quadrature-axis voltage output to a voltage value corresponding to zero quadrature-axis current value; outputting the second voltage control instruction to increase the direct-axis voltage by controlling the direct-axis voltage so as to inject the direct-axis current; When it is monitored that the direct-axis current increases to a fourth specified current value, the fifth voltage control instruction is outputted, and the angle value detected by the resolver sensor within the preset time period is continuously acquired, so as to average all the angle values ​​detected within the preset time period to obtain the fourth resolver angle value; The sixth voltage control instruction is output to reduce the direct-axis voltage to zero.

6. The method according to claim 5, characterized in that The resolver zero point initial value is obtained according to the influence of the change trend in the following manner: If the quadrature-axis current increases the resolver angle value, subtract 180 degrees from the sum of all resolver angle values ​​and divide the result by the number of resolver angle values ​​to obtain the resolver zero point initial value; If the quadrature-axis current reduces the resolver angle value, then the sum of all resolver angle values ​​is added with 180 degrees, and the result is divided by the number of the resolver angle values ​​to obtain the resolver zero point initial value.

7. The method according to claim 6, characterized in that The influence of the quadrature-axis current on the change trend of the resolver angle value is determined by the following method: When the first resolver angle value is greater than the third resolver angle value, and the second resolver angle value is greater than the fourth resolver angle value, determining that the quadrature-axis current increases the resolver angle value; When the first resolver angle value is smaller than the third resolver angle value, and the second resolver angle value is smaller than the fourth resolver angle value, determining the quadrature-axis current causes the resolver angle value to decrease.

8. The method according to claim 1, characterized in that The resolver zero point fine-tuning value is obtained by: outputting a third current control instruction for controlling the quadrature-axis current value and the direct-axis current value, and causing the motor to perform current closed-loop regulation, wherein the third current control instruction instructs controlling the quadrature-axis current value and the direct-axis current value to be zero; Sending a speed command to the dynamometer so that the dynamometer drives the motor to run at a constant speed; Outputting an instruction for adjusting a direct-axis voltage smoothing filter coefficient to smooth the direct-axis voltage; The resolver zero point initial value is used as the initial value of the closed-loop regulator, so that the smoothed direct-axis voltage follows the direct-axis desired voltage through the closed-loop regulator, and the resolver zero point fine-tuning value is output after the closed-loop regulator is stabilized.

9. A resolver zero point calibration device, characterized in that: The device comprises: a first control module, configured to execute the following control steps for the quadrature axis of the motor: outputting a first control instruction when the motor is in a no-load state, the first control instruction including a first rotor control instruction for controlling a rotor angle value of the motor and a first current control instruction for controlling a direct axis current value of the motor; outputting a first voltage control instruction for controlling a quadrature axis voltage value of the motor when it is monitored that an output voltage of the direct axis of the motor satisfies a first condition; and obtaining a first angle value corresponding to the quadrature axis according to a resolver angle value detected by a resolver sensor after the rotor position of the motor is stabilized; a second control module, configured to execute the following control steps for the direct axis of the motor: outputting a second control instruction when the motor is in a no-load state, the second control instruction including the first rotor control instruction and a second current control instruction for controlling the quadrature-axis current value of the motor; outputting a second voltage control instruction for controlling the direct-axis voltage value of the motor when it is monitored that the output voltage of the quadrature-axis of the motor meets a second condition; and obtaining a second angle value corresponding to the direct axis according to the resolver angle value detected by the resolver sensor after the rotor position is stabilized; A determination module is configured to calibrate a resolver zero point of the resolver sensor according to the first angle value and the second angle value, so that the resolver zero point corresponds to a rotor position zero point of the motor, wherein the resolver zero point of the resolver sensor is calibrated in the following manner: determining an influence of a quadrature-axis current on a changing trend of the angle value according to the first angle value and the second angle value, and obtaining a resolver zero point initial value according to the influence of the changing trend; inputting the resolver zero point initial value into a closed-loop regulator of the motor to obtain a resolver zero point fine-tuning value, and storing the resolver zero point fine-tuning value and the resolver zero point initial value, so as to calibrate the resolver zero point according to the resolver zero point initial value and the resolver zero point fine-tuning value.

Images