A method and device for zero-position dynamic calibration of a brushless motor with expanded current intensity oscillation

Abstract

The present application provides a method and device for dynamically calibrating the zero position of a brushless motor with an expanded current intensity oscillation. According to the calibration parameters of the motor to be calibrated, an angle convergence reference curve and a current intensity oscillation expansion reference curve are constructed; the current intensity oscillation expansion reference curve is used to characterize the change pattern in which the d-axis current intensity of the motor rotor expands in a bidirectional reciprocating oscillation manner over time; the motor to be calibrated is driven to operate according to the angle convergence reference curve and the current intensity oscillation expansion reference curve, and an actual angle curve and an actual current intensity curve are obtained; the actual angle curve is compared with the angle convergence reference curve, and the actual current intensity curve is compared with the current intensity oscillation expansion reference curve to determine the zero position calibration effect of the motor to be calibrated; when the zero position calibration effect meets the preset requirements, it is determined that the motor to be calibrated has completed zero position calibration. In this way, efficient and reliable dynamic calibration of the motor zero position can be achieved, avoiding accidents caused by incorrect calibration and ensuring the safe and reliable start-up and operation of the motor.

Description

Technical Field

[0001] The present application relates to the technical field of motors, and in particular, to a method and device for dynamically calibrating the zero position of a brushless motor with current intensity oscillation amplification. Background Art

[0002] For an incremental encoder feedback brushless motor, after the system is completely powered off, motor zero position calibration must be performed again when starting up to ensure that the motor control system can accurately control the position and movement of the motor. Existing zero position calibration methods often only set a fixed angular zero position, and through a sufficiently large current, the rotor permanent magnet can overcome static friction torque, dynamic friction torque, and reaction torque, etc., and try to align to this angular zero position.

[0003] However, in engineering practice, during the calibration process of the motor, it may be in a weak equilibrium state. The zero position pulling force generated by the calibration current is in a state close to parallel with the permanent magnet, and the generated zeroing torque is very small, even insufficient to overcome the static friction torque, reaction torque, etc. generated by the motor, reducer, load, etc., resulting in calibration failure. The motor shaft is also often subject to various unexpected interference torques, making it impossible for the rotor permanent magnet of the motor to align to the angular zero position, and the accuracy of zero position calibration is low, affecting the stability of motor operation. In addition, the existing calibration methods lack monitoring of the zero position calibration effect, so that the motor control system controls the motor to start production operation when the calibration error is large, which is likely to cause accidents. Summary of the Invention

[0004] In view of this, the purpose of the present application is to provide a method and device for dynamically calibrating the zero position of a brushless motor with current intensity oscillation amplification, so as to solve the problems of low accuracy and reliability existing in the zero position calibration method in the prior art, realize efficient and reliable dynamic calibration of the motor zero position, avoid accidents caused by incorrect calibration, and ensure the safe and reliable start-up and operation of the motor.

[0005] The embodiment of the present application provides a method for dynamically calibrating the zero position of a brushless motor with current intensity oscillation amplification, and the dynamic calibration method includes:

[0006] Determine the calibration parameters of the motor to be calibrated;

[0007] According to the calibration parameters, construct an angular convergence reference curve and a current intensity oscillation amplification reference curve for the motor to be calibrated; wherein, the angular convergence reference curve is used to characterize the movement mode of the motor rotor converging from the initial angular position to the angular zero position over time; the current intensity oscillation amplification reference curve is used to characterize the change mode of the d-axis current intensity of the motor rotor expanding in a bidirectional reciprocating oscillation manner over time;

[0008] Drive the motor to be calibrated according to the angle convergence reference curve and the current intensity oscillation expansion reference curve, and obtain the actual angle curve and the actual current intensity curve of the motor to be calibrated; wherein, the actual angle curve refers to the curve formed by the actual angle positions corresponding to different operating times of the motor rotor; the actual current intensity curve refers to the curve formed by the d-axis current intensity corresponding to different operating times of the motor rotor;

[0009] Compare the actual angle curve with the angle convergence reference curve, and compare the actual current intensity curve with the current intensity oscillation expansion reference curve to determine the zero position calibration effect of the motor to be calibrated;

[0010] When the zero position calibration effect meets the preset requirements, it is determined that the zero position calibration of the motor to be calibrated is completed.

[0011] Further, obtaining the actual angle curve and the actual current intensity curve of the motor to be calibrated includes:

[0012] Determine the stop angle according to the angle zero position and the preset error angle value;

[0013] Record the actual angle position and the actual d-axis current intensity corresponding to each operating time until the actual angle position corresponding to any operating time reaches the stop angle;

[0014] Based on the actual angle positions corresponding to each recorded operating time, obtain the actual angle curve; and based on the actual d-axis current intensities corresponding to each recorded operating time, obtain the actual current intensity curve.

[0015] Further, comparing the actual angle curve with the angle convergence reference curve, and comparing the actual current intensity curve with the current intensity oscillation expansion reference curve to determine the zero position calibration effect of the motor to be calibrated includes:

[0016] Compare the actual angle curve with the angle convergence reference curve, and intercept a preset time period forward from the operating time when the stop angle is reached to obtain an angle difference curve;

[0017] Through the integral operation of the angle difference curve, obtain the average angle error of the motor to be calibrated within the preset time period; wherein, the average angle error is used to measure the zero position calibration effect of the motor to be calibrated;

[0018] Compare the actual current intensity curve with the current intensity oscillation expansion reference curve, and intercept a preset time period forward from the operating time when the stop angle is reached to obtain a current intensity difference curve;

[0019] By integrating the current intensity difference curve, the average current intensity error of the motor to be calibrated within the preset duration is obtained; wherein, the average current intensity error is used to measure the zero position calibration effect of the motor to be calibrated.

[0020] Further, the dynamic calibration method further includes determining that the zero position calibration effect meets the preset requirements by the following method:

[0021] When the average angle error is less than the preset angle error threshold and the average current intensity error is less than the preset current intensity error threshold, it is determined that the zero position calibration effect meets the preset requirements.

[0022] Further, the calibration parameters include the current bidirectional oscillation frequency and the current amplification factor; determining the calibration parameters of the motor to be calibrated includes:

[0023] Obtain the rated speed, rated current and overload capacity of the motor to be calibrated;

[0024] According to the rated speed of the motor to be calibrated, determine the motor frequency corresponding to the motor to be calibrated;

[0025] Reduce the motor frequency by a predetermined multiple to determine the current bidirectional oscillation frequency;

[0026] According to the rated current and overload capacity of the motor to be calibrated, determine the current amplification factor; wherein, the current amplification factor is used to control the amplification speed of the d-axis current intensity of the motor rotor.

[0027] Further, according to the calibration parameters, constructing the current intensity oscillation amplification reference curve of the motor to be calibrated includes:

[0028] Determine the current bidirectional oscillation function according to the current bidirectional oscillation frequency;

[0029] Construct the current intensity oscillation amplification reference curve according to the product of the current amplification factor and the current bidirectional oscillation function.

[0030] Further, the formula of the current intensity oscillation amplification reference curve is expressed as:

[0031] R ref =k×t×sin(2πft)

[0032] wherein, R ref represents the current intensity oscillation convergence reference curve; k represents the current amplification factor; f represents the current bidirectional oscillation frequency.

[0033] Further, the dynamic calibration method further includes:

[0034] When the zero-position calibration effect does not meet the preset requirements, determine whether the number of zero-position calibration times of the motor to be calibrated reaches the preset number threshold;

[0035] If not, re-perform zero-position calibration on the motor to be calibrated;

[0036] If it has reached, generate an alarm signal and send it to relevant personnel.

[0037] The embodiment of the present application also provides a zero-position dynamic calibration device for a brushless motor with current intensity oscillation amplification. The dynamic calibration device includes:

[0038] A determination module, configured to determine the calibration parameters of the motor to be calibrated;

[0039] A construction module, configured to construct an angle convergence reference curve and a current intensity oscillation amplification reference curve of the motor to be calibrated according to the calibration parameters; wherein, the angle convergence reference curve is used to characterize the motion mode of the motor rotor converging from the initial angle position to the zero angle over time; the current intensity oscillation amplification reference curve is used to characterize the change mode of the d-axis current intensity of the motor rotor expanding in a bidirectional reciprocating oscillation manner over time;

[0040] An acquisition module, configured to drive the motor to be calibrated to operate according to the angle convergence reference curve and the current intensity oscillation amplification reference curve, and acquire the actual angle curve and the actual current intensity curve of the motor to be calibrated; wherein, the actual angle curve refers to the curve formed by the actual angle positions corresponding to the motor rotor at different operating times; the actual current intensity curve refers to the curve formed by the d-axis current intensities corresponding to the motor rotor at different operating times;

[0041] A comparison module, configured to compare the actual angle curve and the angle convergence reference curve, and compare the actual current intensity curve and the current intensity oscillation amplification reference curve, to determine the zero-position calibration effect of the motor to be calibrated;

[0042] A judgment module, configured to determine that the zero-position calibration of the motor to be calibrated is completed when the zero-position calibration effect meets the preset requirements.

[0043] The embodiment of the present application also provides an electronic device, including: a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device runs, the processor communicates with the memory through the bus. When the machine-readable instructions are executed by the processor, the steps of the above zero-position dynamic calibration method for a brushless motor with current intensity oscillation amplification are executed.

[0044] An embodiment of the present application further provides a computer-readable storage medium, on which a computer program is stored. When the computer program is run by a processor, it executes the steps of the above-mentioned method for dynamically calibrating the zero position of a brushless motor by expanding current intensity oscillation.

[0045] A method and device for dynamically calibrating the zero position of a brushless motor by expanding current intensity oscillation provided by an embodiment of the present application. On the one hand, by comprehensively using an angle convergence reference curve and a current intensity oscillation expansion reference curve for dynamic calibration, the angular position dynamically approaches the angular zero position; at the same time, the d-axis current intensity continuously expands in a bidirectional reciprocating oscillation manner, increasing the torque, thereby breaking the static and quasi-static balance generated by a large initial static friction torque and a non-linear dynamic friction torque, enabling the motor to generate significant calibration actions, overcoming various interference torques, and improving the calibration accuracy; on the other hand, by comparing the actual angle curve and the angle oscillation convergence reference curve, the zero position calibration effect of the motor can be quantitatively determined, improving the reliability of calibration; and when it is determined that the zero position calibration effect meets the preset requirements, the zero position calibration is completed, which helps to ensure the safe operation of the motor.

[0046] To make the above objects, features, and advantages of the present application more obvious and understandable, the following specifically gives preferred embodiments and, in conjunction with the accompanying drawings, makes the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] To more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings required for use in the embodiments. It should be understood that the following drawings only show some embodiments of the present application and should not be regarded as limiting the scope. For those of ordinary skill in the art, other related drawings can be obtained based on these drawings without creative efforts.

[0048] Figure 1 Shows a flowchart of a method for dynamically calibrating the zero position of a brushless motor by expanding current intensity oscillation provided by an embodiment of the present application;

[0049] Figure 2 Shows a schematic diagram of a calibration process provided by an embodiment of the present application;

[0050] Figure 3 Shows a schematic structural diagram of a device for dynamically calibrating the zero position of a brushless motor by expanding current intensity oscillation provided by an embodiment of the present application;

[0051] Figure 4 Shows a schematic structural diagram of an electronic device provided by an embodiment of the present application. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0052] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are only a part rather than all of the embodiments of this application. The components of the embodiments of this application usually described and illustrated in the accompanying drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. Based on the embodiments of this application, every other embodiment obtained by those skilled in the art without creative efforts falls within the scope of protection of this application.

[0053] Through research, it is found that the existing zero-position calibration method is very simple. Usually, only a fixed angular zero position is set, and then the d-axis of the dq coordinate system of the motor FOC algorithm is aligned to the specified angular zero position q0. By applying a sufficiently large current, the rotor permanent magnet NS poles can overcome static friction torque, dynamic friction torque, and reaction torque, etc., and try to align to this angular zero position.

[0054] However, in engineering practice, during the calibration process of the motor, it may be in a weakly balanced state. The zero-position pulling force generated by the calibration current is in a state close to parallel with the permanent magnet, and the generated zeroing torque is very small, or even insufficient to overcome the static friction torque, reaction torque, etc. generated by the motor, reducer, load, etc., resulting in calibration failure. The motor shaft is also often subject to various unexpected interference torques, making it impossible for the rotor permanent magnet of the motor to align to the angular zero position, and the accuracy of zero-position calibration is relatively low, affecting the stability of motor operation. In addition, the existing calibration method lacks monitoring of the zero-position calibration effect, so that the motor control system controls the motor to start production operation when the calibration error is large, which is likely to cause accidents.

[0055] Based on this, the embodiments of this application provide a method for dynamically calibrating the zero position of a brushless motor with current intensity oscillation amplification to solve the problems of low accuracy and reliability existing in the zero-position calibration method in the prior art.

[0056] Please refer to Figure 1 , Figure 1 , which is a flowchart of a method for dynamically calibrating the zero position of a brushless motor with current intensity oscillation amplification provided by the embodiments of this application. This dynamic calibration method can be automatically executed by the motor driver. As shown in Figure 1 , the dynamic calibration method provided by the embodiments of this application includes:

[0057] S101. Determine the calibration parameters of the motor to be calibrated.

[0058] Among them, the calibration parameters may include current calibration parameters and angle calibration parameters; among them, the current calibration parameters include the current bidirectional oscillation frequency and the current amplification coefficient; the current amplification coefficient is used to control the amplification speed of the d-axis current intensity of the motor rotor.

[0059] The angle calibration parameters may include a deviation angle value and an angle attenuation coefficient. The deviation angle value refers to the angle value by which the initial angle position of the motor rotor (more specifically, the permanent magnet on the rotor) deviates from the angle zero position; the angle attenuation coefficient is used to control the angle convergence speed of the motor rotor, that is, the speed at which the permanent magnet approaches the angle zero position.

[0060] In specific implementation, the parameter values of each calibration parameter can be set according to the actual application scenario of the motor and in combination with the calibration requirements to achieve flexible calibration of the motor.

[0061] In a possible implementation manner, step S101 may include:

[0062] S1011. Obtain the rated speed, rated current, and overload capacity of the motor to be calibrated.

[0063] Among them, the overload capacity of the motor refers to the ability of the motor to still operate stably in a short time when it exceeds its rated load, usually expressed in multiples. Exemplarily, the overload capacity of a general motor can reach 3 times its rated load, and the duration can usually be 1 minute.

[0064] S1012. Determine the motor frequency corresponding to the motor to be calibrated according to the rated speed of the motor to be calibrated.

[0065] S1013. Reduce the motor frequency by a predetermined multiple to determine the current bidirectional oscillation frequency.

[0066] Regarding steps S1012 and S1013, the bidirectional oscillation frequency f when the motor current expands is related to the rated speed of the motor; specifically, the rated speed of the motor to be calibrated has a corresponding frequency. For example, if the rated speed of the motor to be calibrated is 3000 RPM, that is, 50 Hz, f can reduce the motor frequency by a predetermined multiple and be taken as not greater than one-tenth of the frequency generated by the rated speed of the motor, that is, f is not greater than 5 Hz; exemplarily, it can be taken as 2 Hz.

[0067] S1014. Determine the current amplification coefficient according to the rated current and overload capacity of the motor to be calibrated.

[0068] Here, the parameter value of the current amplification coefficient k is related to the rated current of the motor and the overload capacity. Exemplarily, the rated current of the motor is 5 A, and it can generally be overloaded 3 times, that is, 15 A; the total zero position calibration process is 5 seconds, and during this period, the reference curve R for the oscillation expansion of the current intensityref The reference value of the current intensity on it can reach 3 times the rated current of the motor, then k = 15A / 5s = 3A / s.

[0069] S102. Construct an angle convergence reference curve and a current intensity oscillation expansion reference curve for the motor to be calibrated according to the calibration parameters.

[0070] Among them, the angle convergence reference curve is used to characterize the motion mode of the motor rotor converging from the initial angle position to the zero angle position over time; the current intensity oscillation expansion reference curve is used to characterize the change mode of the d-axis current intensity of the motor rotor expanding in a bidirectional reciprocating oscillation manner over time.

[0071] In a possible implementation manner, step S102 may include:

[0072] Determine a current bidirectional oscillation function according to the current bidirectional oscillation frequency; construct the current intensity oscillation expansion reference curve according to the product of the current expansion coefficient and the current bidirectional oscillation function.

[0073] In an example, the formula of the current intensity oscillation expansion reference curve can be expressed as:

[0074] R ref = k × t × sin(2πft)

[0075] Among them, R ref represents the current intensity oscillation convergence reference curve, and each point on the curve represents the d-axis current intensity of the rotor in the motor stator coordinate system at the running moment; k represents the current expansion coefficient; f represents the current bidirectional oscillation frequency.

[0076] Next, please refer to Figure 2 , Figure 2 which is a schematic diagram of the calibration process when the angle position converges unidirectionally provided by an embodiment of the present application. As Figure 2 the angle convergence reference curve Q ref shown, the angle position converges to the zero angle; as the current intensity oscillation expansion reference curve R ref shown, the current intensity increases and decreases continuously in a bidirectional reciprocating oscillation manner, but the oscillation amplitude gradually expands.

[0077] It should be noted that the alignment torque of the brushless motor is proportional to the d-axis current intensity, that is, the alignment torque can be adjusted by adjusting the d-axis current.

[0078] It can be seen that as time goes by, the oscillation of the current intensity expands, causing the alignment torque intensity to also oscillate and expand. In an oscillating manner, it can better break the static and quasi-static balance caused by a large initial static friction torque and non-linear dynamic friction torque, and overcome various resistances to perform significant calibration actions. On the other hand, the expansion of the current intensity oscillation makes the effective current value during the zero-position dynamic calibration process significantly smaller than that during linear growth. By reducing the effective current value, power consumption can be reduced and electrical energy can be saved. More importantly, through research, it is found that the motor, especially the motor driver therein, is very sensitive to the magnitude of the current. By reducing the effective current value during the dynamic calibration process, the motor load can be reduced, the calibration safety can be better ensured, and potential safety hazards caused by excessive current can be reduced.

[0079] In addition, for the motion mode characterized by the angle convergence reference curve, the angular position of the motor rotor can converge unidirectionally or converge in a bidirectional reciprocating oscillation; as Figure 2 shown in a schematic diagram of unidirectional convergence of the angular position. Further, the angular position can also converge in a reciprocal form or an exponential form, etc.

[0080] Exemplarily, when the angular position of the motor to be calibrated converges unidirectionally in an exponential form, the formula of the angle convergence reference curve can be expressed as:

[0081] Q ref = q0 + a × e -bt

[0082] where, Q ref represents the angle convergence reference curve; q0 represents the angular zero position, with the unit of °; Q ref and q0 are both the rotor d-axis angles in the motor stator coordinate system; a represents the deviation angle value; b represents the angle attenuation coefficient; t represents the running time, with the unit of s.

[0083] S103. Drive the motor to be calibrated according to the angle convergence reference curve and the current intensity oscillation expansion reference curve, and obtain the actual angle curve and the actual current intensity curve of the motor to be calibrated.

[0084] Among them, the actual angle curve refers to the curve formed by the actual angular positions corresponding to different running times of the motor rotor; the actual current intensity curve refers to the curve formed by the d-axis current intensities corresponding to different running times of the motor rotor.

[0085] In specific implementation, it can be controlled in combination with the FOC algorithm of the motor driver. FOC (Field-Oriented Control) is a control algorithm for AC motors (such as brushless DC motors BLDC and permanent magnet synchronous motors PMSM, etc.). Its core idea is to decompose the three-phase current and voltage of the motor into two independent DC components: the magnetic field component (d-axis) and the torque component (q-axis), so as to achieve independent control of the motor magnetic field and torque.

[0086] In one example, the actual angle curve and the actual current intensity curve of the motor to be calibrated can be obtained through the following steps:

[0087] Determine the stop angle according to the angle zero position and the preset error angle value; record the actual angle position and the actual d-axis current intensity corresponding to each running moment until the actual angle position corresponding to any running moment reaches the stop angle; obtain the actual angle curve based on the actual angle positions corresponding to each recorded running moment; and obtain the actual current intensity curve based on the actual d-axis current intensities corresponding to each recorded running moment.

[0088] Continue to refer to Figure 2 , under the drive of the d-axis current mode, the motor starts to run and gradually approaches the zero position q0 according to the angle convergence reference curve Q ref while gradually expanding the torque intensity in a bidirectional reciprocating oscillation manner according to the current intensity oscillation expansion reference curve R ref ; when Q ref reaches the q1 position and the deviation d = abs(q1 - q0) at this time reaches the allowed preset error angle value, the motor stops, and the motor driver automatically records the actual angle curve Q act and the actual current intensity curve R act . Among them, the magnitude of the deviation d can be set according to the required calibration accuracy, such as ±0.1°.

[0089] S104. Compare the actual angle curve with the angle convergence reference curve, and compare the actual current intensity curve with the current intensity oscillation expansion reference curve to determine the zero position calibration effect of the motor to be calibrated.

[0090] In this step, by comparing the actual angle curve with the angle convergence reference curve, the deviation degree between the actual curve and the reference curve in terms of angle during the dynamic zero position calibration process can be determined; at the same time, by comparing the actual current intensity curve with the current intensity oscillation expansion reference curve, the deviation degree between the actual curve and the reference curve in terms of current intensity during the dynamic zero position calibration process can be determined; and then the more comprehensive zero position calibration effect can be determined by synthesizing the deviation degree in terms of angle and the deviation degree in terms of current intensity.

[0091] In a possible implementation, step S104 may include:

[0092] S1041. Compare the actual angle curve and the angle convergence reference curve, and intercept a preset time duration forward from the running moment when reaching the stop angle to obtain an angle difference curve.

[0093] S1042. Through integral operation on the angle difference curve, obtain the average angle error of the motor to be calibrated within the preset time duration; wherein, the average angle error is used to measure the zero position calibration effect of the motor to be calibrated.

[0094] S1043. Compare the actual current intensity curve and the current intensity oscillation expansion reference curve, and intercept a preset time duration forward from the running moment when reaching the stop angle to obtain a current intensity difference curve.

[0095] S1044. Through integral operation on the current intensity difference curve, obtain the average current intensity error of the motor to be calibrated within the preset time duration; wherein, the average current intensity error is used to measure the zero position calibration effect of the motor to be calibrated.

[0096] Here, the preset time duration is the integral time span T0; more specifically, in the embodiments of the present application, by comparing the actual angle curve and the angle oscillation convergence reference curve, an evaluation function J1 for the zero position calibration effect in terms of angle and an evaluation function J2 for the zero position calibration effect in terms of current intensity are defined, and the formula can be expressed as:

[0097]

[0098] The magnitude of the average angle error (i.e., the value of the evaluation function J1) reflects the severity of the deviation of the actual movement curve of the angle from the angle reference curve during the process of the permanent magnet approaching the zero position q0; the magnitude of the average current intensity error (i.e., the value of the evaluation function J2) reflects the severity of the deviation of the actual change curve of the current intensity from the current intensity reference curve during the process of the permanent magnet approaching the zero position q0. Obviously, when the values of J1 and J2 are very small, it indicates that the actual approaching curve of the permanent magnet basically coincides with the angle reference curve, that is, the approaching convergence effect is very good. At this time, the motor calibration is successful, and both the calibration dynamic process and the calibration result are very good. When the value of J1 or J2 is not small enough, that is, greater than the preset error threshold, the calibration error is too large, the motor calibration fails, and it is necessary to re-calibrate or check the problems in the motor system.

[0099] Thus, compared with the method of only calculating the difference between the finally actually calibrated zero position and the preset angle zero position, or only calculating the difference between the finally actual current intensity and the preset current intensity, the evaluation function J designed in the embodiments of the present application AJ1 and J2 can better reflect the overall severity of the deviation of the actual motion curve from the angle reference curve during the overall process of zero-position dynamic calibration, so as to more accurately and comprehensively measure the zero-position calibration effect.

[0100] S105. When the zero-position calibration effect meets the preset requirements, it is determined that the motor to be calibrated has completed zero-position calibration.

[0101] Here, when the average angle error is less than the preset error threshold and the average current intensity error is less than the preset current intensity error threshold, it is determined that the zero-position calibration effect meets the preset requirements, and the motor is allowed to perform subsequent operations.

[0102] When the zero-position calibration effect does not meet the preset requirements (that is, J1 or J2 is greater than or equal to the preset error threshold), it indicates that the zero-position calibration fails this time. Then, it is judged whether the number of zero-position calibration times of the motor to be calibrated reaches the preset number threshold. If not, the zero-position calibration of the motor to be calibrated is automatically restarted. If it has reached, an alarm signal is generated and sent to relevant personnel to remind relevant personnel to perform manual intervention. The number threshold can be set according to actual needs, such as 3 times.

[0103] A zero-position dynamic calibration method for a brushless motor with current intensity oscillation expansion provided by an embodiment of the present application. On the one hand, the angle convergence reference curve and the current intensity oscillation expansion reference curve are comprehensively used for dynamic calibration to make the angle position dynamically approach the angle zero position. At the same time, the d-axis current intensity continuously expands in a bidirectional reciprocating oscillation manner to increase the torque, thereby breaking the static and quasi-static balance generated by the large initial static friction torque and the non-linear dynamic friction torque, so that the motor can generate significant calibration actions, overcome various interference torques, and improve the calibration accuracy. On the other hand, by comparing the actual angle curve and the angle oscillation convergence reference curve, the zero-position calibration effect of the motor can be quantitatively determined, and the reliability of the calibration can be improved. And when it is determined that the zero-position calibration effect meets the preset requirements, the zero-position calibration is completed, which helps to ensure the safe operation of the motor.

[0104] Please refer to Figure 3 , Figure 3 which is a schematic structural diagram of a zero-position dynamic calibration device for a brushless motor with current intensity oscillation expansion provided by an embodiment of the present application. As shown in Figure 3 , the dynamic calibration device 300 includes:

[0105] A determination module 310, configured to determine the calibration parameters of the motor to be calibrated;

[0106] A building module 320, configured to construct an angle convergence reference curve and a current intensity oscillation amplification reference curve of the motor to be calibrated according to the calibration parameters; wherein, the angle convergence reference curve is used to characterize the motion mode of the motor rotor converging from the initial angle position to the angle zero position over time; the current intensity oscillation amplification reference curve is used to characterize the change mode of the d-axis current intensity of the motor rotor expanding in a bidirectional reciprocating oscillation manner over time;

[0107] An acquisition module 330, configured to drive the motor to be calibrated to operate according to the angle convergence reference curve and the current intensity oscillation amplification reference curve, and acquire the actual angle curve and the actual current intensity curve of the motor to be calibrated; wherein, the actual angle curve refers to the curve formed by the actual angle positions corresponding to different operating moments of the motor rotor; the actual current intensity curve refers to the curve formed by the d-axis current intensities corresponding to different operating moments of the motor rotor;

[0108] A comparison module 340, configured to compare the actual angle curve and the angle convergence reference curve, and compare the actual current intensity curve and the current intensity oscillation amplification reference curve, to determine the zero position calibration effect of the motor to be calibrated;

[0109] A judgment module 350, configured to determine that the zero position calibration of the motor to be calibrated is completed when the zero position calibration effect meets the preset requirements.

[0110] Further, when the acquisition module 330 is used to acquire the actual angle curve and the actual current intensity curve of the motor to be calibrated, the acquisition module 330 is configured to:

[0111] Determine a stop angle according to the angle zero position and a preset error angle value;

[0112] Record the actual angle position and the actual d-axis current intensity corresponding to each operating moment until the actual angle position corresponding to any operating moment reaches the stop angle;

[0113] Based on the actual angle positions corresponding to each recorded operating moment, obtain the actual angle curve; and based on the actual d-axis current intensities corresponding to each recorded operating moment, obtain the actual current intensity curve.

[0114] Further, when the comparison module 340 is used to compare the actual angle curve and the angle convergence reference curve, and compare the actual current intensity curve and the current intensity oscillation amplification reference curve, to determine the zero position calibration effect of the motor to be calibrated, the comparison module 340 is configured to:

[0115] Compare the actual angle curve with the reference angle convergence curve, and intercept a preset time duration forward from the running moment when the stop angle is reached to obtain an angle difference curve;

[0116] Through integral operation on the angle difference curve, obtain the average angle error of the motor to be calibrated within the preset time duration; wherein, the average angle error is used to measure the zero position calibration effect of the motor to be calibrated;

[0117] Compare the actual current intensity curve with the reference curve for current intensity oscillation amplification, and intercept a preset time duration forward from the running moment when the stop angle is reached to obtain a current intensity difference curve;

[0118] Through integral operation on the current intensity difference curve, obtain the average current intensity error of the motor to be calibrated within the preset time duration; wherein, the average current intensity error is used to measure the zero position calibration effect of the motor to be calibrated.

[0119] Further, the determination module 350 is further configured to determine that the zero position calibration effect meets the preset requirements in the following manner:

[0120] When the average angle error is less than a preset angle error threshold and the average current intensity error is less than a preset current intensity error threshold, determine that the zero position calibration effect meets the preset requirements.

[0121] Further, the calibration parameters include the current bidirectional oscillation frequency and the current amplification coefficient; when the determination module 310 is used to determine the calibration parameters of the motor to be calibrated, the determination module is configured to:

[0122] Obtain the rated speed, rated current, and overload capacity of the motor to be calibrated;

[0123] According to the rated speed of the motor to be calibrated, determine the motor frequency corresponding to the motor to be calibrated;

[0124] Reduce the motor frequency by a predetermined multiple to determine the current bidirectional oscillation frequency;

[0125] According to the rated current and overload capacity of the motor to be calibrated, determine the current amplification coefficient; wherein, the current amplification coefficient is used to control the amplification speed of the d-axis current intensity of the motor rotor.

[0126] Further, when the construction module 320 is used to construct the reference angle convergence curve and the reference curve for current intensity oscillation amplification of the motor to be calibrated according to the calibration parameters, the construction module 320 is configured to:

[0127] Determine a current bidirectional oscillation function according to the current bidirectional oscillation frequency;

[0128] Construct the oscillation amplification reference curve of the current intensity according to the product of the described current amplification factor and the current bidirectional oscillation function.

[0129] Furthermore, the formula of the oscillation amplification reference curve of the current intensity is expressed as:

[0130] R ref = k × t × sin(2πft)

[0131] Wherein, R ref represents the oscillation convergence reference curve of the current intensity; k represents the current amplification factor; f represents the current bidirectional oscillation frequency.

[0132] Furthermore, the determination module 350 is further configured to:

[0133] When the zero position calibration effect does not meet the preset requirements, determine whether the number of zero position calibration times of the motor to be calibrated reaches the preset number threshold;

[0134] If not, re-perform zero position calibration on the motor to be calibrated;

[0135] If it has reached, generate an alarm signal and send it to relevant personnel.

[0136] Please refer to Figure 4 , Figure 4 , which is a schematic structural diagram of an electronic device provided by an embodiment of the present application. As Figure 4 shown in

[0137] The memory 420 stores machine-readable instructions executable by the processor 410. When the electronic device 400 runs, the processor 410 communicates with the memory 420 through the bus 430. When the machine-readable instructions are executed by the processor 410, the steps of the zero position dynamic calibration method of the brushless motor with oscillation amplification of current intensity in the method embodiment as described above can be executed. The specific implementation manner can refer to the method embodiment and will not be elaborated here. Figure 1 shown in

[0138] An embodiment of the present application further provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. When the computer program is run by a processor, the steps of the zero position dynamic calibration method of the brushless motor with oscillation amplification of current intensity in the method embodiment as described above can be executed. The specific implementation manner can refer to the method embodiment and will not be elaborated here. Figure 1 shown in

[0139] Those skilled in the art can 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 foregoing method embodiments and will not be elaborated herein.

[0140] In several embodiments provided in the present 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 illustrative. For example, the division of the units is only a logical functional division, and there may be other division methods in actual implementation. For another example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed couplings or direct couplings or communication connections to each other can be through some communication interfaces, and the indirect couplings or communication connections of the devices or units can be in electrical, mechanical, or other forms.

[0141] The units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0142] In addition, in each embodiment of the present application, the functional units can be integrated into one processing unit, or each unit can exist physically alone, or two or more units can be integrated into one unit.

[0143] If the functions are implemented in the form of software function units and sold or used as independent products, they can be stored in a non-volatile computer-readable storage medium executable by a processor. Based on such an understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or a part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions for causing a computer device (which can be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in each embodiment of the present application. The foregoing storage medium includes: various media that can store program codes such as USB flash drives, mobile hard disks, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical discs.

[0144] Finally, it should be noted that the above-described embodiments are only specific embodiments of the present application, used to illustrate the technical solutions of the present application, rather than limiting it. The protection scope of the present application is not limited thereto. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that any person skilled in the art within the technical scope disclosed by the present application can still modify the technical solutions recorded in the foregoing embodiments or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be covered within the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A zero - position dynamic calibration method for a brushless motor with amplified current intensity oscillation, characterized in that, The dynamic calibration method includes: Determine the calibration parameters of the motor to be calibrated; Construct an angular convergence reference curve and a current intensity oscillation amplification reference curve for the motor to be calibrated according to the calibration parameters; wherein, the angular convergence reference curve is used to characterize the motion mode of the motor rotor converging from the initial angular position to the angular zero position over time; the current intensity oscillation amplification reference curve is used to characterize the changing mode in which the axial current intensity of the motor rotor expands in a bidirectional reciprocating oscillation manner over time; Drive the motor to be calibrated according to the angle convergence reference curve and the current intensity oscillation expansion reference curve, and obtain the actual angle curve and the actual current intensity curve of the motor to be calibrated; wherein, the actual angle curve refers to the curve formed by the actual angle positions corresponding to the motor rotor at different operating times; the actual current intensity curve refers to the curve formed by the shaft current intensity; Compare the actual angle curve and the reference angle convergence curve, and compare the actual current intensity curve and the reference current intensity oscillation amplification curve to determine the zero-position calibration effect of the motor to be calibrated; When the zero-position calibration effect meets the preset requirements, determine that the motor to be calibrated has completed zero-position calibration; The calibration parameters include the bidirectional current oscillation frequency and the current amplification coefficient; determining the calibration parameters of the motor to be calibrated includes: Obtain the rated speed, rated current and overload capacity of the motor to be calibrated; Determine the motor frequency corresponding to the motor to be calibrated according to the rated speed of the motor to be calibrated; Reduce the motor frequency by a predetermined multiple to determine the bidirectional current oscillation frequency; Determine the current amplification factor according to the rated current and overload capacity of the motor to be calibrated; wherein, the current amplification factor is used to control the expansion rate of the shaft current intensity of the motor rotor; Construct the reference current intensity oscillation amplification curve of the motor to be calibrated according to the calibration parameters, including: Determine the bidirectional current oscillation function according to the bidirectional current oscillation frequency; Construct the reference current intensity oscillation amplification curve according to the product of the current amplification coefficient and the bidirectional current oscillation function.

2. The dynamic calibration method according to claim 1, characterized in that Obtain the actual angle curve and the actual current intensity curve of the motor to be calibrated, including: Determine the stop angle according to the zero angle and the preset error angle value; Record the actual angular position and actual shaft current intensity corresponding to each running moment until the actual angular position corresponding to any running moment reaches the stop angle; Based on the actual angular positions corresponding to each recorded running moment, obtain the actual angular curve; and based on the actual axis current intensity corresponding to each recorded running moment, obtain the actual curve of the current intensity.

3. The dynamic calibration method according to claim 2, wherein Comparing the actual angle curve and the reference angle convergence curve, and comparing the actual current intensity curve and the reference current intensity oscillation amplification curve to determine the zero-position calibration effect of the motor to be calibrated, including: Compare the actual angle curve and the reference angle convergence curve, and intercept a preset time period forward from the running moment when the stop angle is reached to obtain an angle difference curve; Through the integral operation of the angle difference curve, obtain the average angle error of the motor to be calibrated within the preset time period; wherein, the average angle error is used to measure the zero-position calibration effect of the motor to be calibrated; Compare the actual current intensity curve and the reference current intensity oscillation amplification curve, and intercept a preset time period forward from the running moment when the stop angle is reached to obtain a current intensity difference curve; Through the integral operation of the current intensity difference curve, obtain the average current intensity error of the motor to be calibrated within the preset time period; wherein, the average current intensity error is used to measure the zero-position calibration effect of the motor to be calibrated.

4. The dynamic calibration method according to claim 3, characterized in that, The dynamic calibration method further includes determining that the zero-position calibration effect meets the preset requirements by the following method: When the average angle error is less than the preset angle error threshold and the average current intensity error is less than the preset current intensity error threshold, determine that the zero-position calibration effect meets the preset requirements.

5. The dynamic calibration method according to claim 1, characterized in that The formula representation of the reference current intensity oscillation amplification curve is: Among them, represents the reference curve for the convergence of the current intensity oscillation; represents the current amplification factor; represents the bidirectional oscillation frequency of the current.

6. The dynamic calibration method according to claim 1, characterized in that The dynamic calibration method further includes: When the zero-position calibration effect does not meet the preset requirements, determine whether the number of zero-position calibration times of the motor to be calibrated reaches the preset number threshold; If not, re-perform zero-position calibration on the motor to be calibrated; If it has reached, generate an alarm signal and send it to relevant personnel.

7. A zero - position dynamic calibration device for a brushless motor with amplified current intensity oscillation, characterized in that, The dynamic calibration device includes: A determination module for determining the calibration parameters of the motor to be calibrated; A building block for constructing an angle convergence reference curve and a current intensity oscillation amplification reference curve of the motor to be calibrated according to the calibration parameters; wherein, the angle convergence reference curve is used to characterize the motion mode of the motor rotor converging from the initial angle position to the zero angle position over time; the current intensity oscillation amplification reference curve is used to characterize the Change mode in which the shaft current intensity expands in a bidirectional reciprocating oscillation manner over time; An acquisition module, configured to drive the motor to be calibrated to operate according to the angle convergence reference curve and the current intensity oscillation expansion reference curve, and acquire the actual angle curve and the actual current intensity curve of the motor to be calibrated; wherein, the actual angle curve refers to a curve formed by the actual angle positions corresponding to the motor rotor at different operating times; the actual current intensity curve refers to the curve formed by the shaft current intensity; A comparison module, configured to compare the actual angle curve and the angle convergence reference curve, and compare the actual current intensity curve and the current intensity oscillation amplification reference curve, to determine the zero position calibration effect of the motor to be calibrated; A judgment module, configured to determine that the motor to be calibrated completes zero position calibration when the zero position calibration effect meets a preset requirement; The calibration parameters include a current bidirectional oscillation frequency and a current amplification coefficient; when the determination module is used to determine the calibration parameters of the motor to be calibrated, the determination module is configured to: Obtain the rated speed, rated current and overload capacity of the motor to be calibrated; Determine the motor frequency corresponding to the motor to be calibrated according to the rated speed of the motor to be calibrated; Reduce the motor frequency by a predetermined multiple to determine the current bidirectional oscillation frequency; Determine the current amplification factor according to the rated current and overload capacity of the motor to be calibrated; wherein, the current amplification factor is used to control the expansion speed of the shaft current intensity of the motor rotor; When the construction module is used to construct the angle convergence reference curve and the current intensity oscillation amplification reference curve of the motor to be calibrated according to the calibration parameters, the construction module is configured to: Determine a current bidirectional oscillation function according to the current bidirectional oscillation frequency; Construct the current intensity oscillation amplification reference curve according to the product of the current amplification coefficient and the current bidirectional oscillation function.

8. An electronic device, characterized in that, Including: A processor, a memory and a bus, where the memory stores machine-readable instructions executable by the processor. When the electronic device runs, the processor communicates with the memory through the bus. When the machine-readable instructions are run by the processor, the steps of the zero position dynamic calibration method for a brushless motor with current intensity oscillation amplification as described in any one of claims 1 to 6 are executed.

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