Control method of servo motor, servo driver and servo system

Abstract

The application discloses a kind of control method of servo motor, servo driver and servo system, belong to motor control technical field, in the application, first, the actual angular velocity of monitoring servo motor is obtained according to the rotational speed instruction of servo motor, and then, according to the deviation between actual angular velocity and theoretical angular velocity, obtain vibration signal to the rotational speed instruction of servo motor is adjusted, to control servo motor operation by adjusted target rotational speed instruction;Since vibration signal can represent the low-frequency vibration characteristics of servo motor, and vibration signal will not be influenced by resonance frequency offset, so, by adjusted target rotational speed instruction control servo motor operation can suppress mechanical resonance in the process of servo motor operation, compared with using notch filter to realize the resonance suppression of servo system, improve the reliability of servo motor control method in resonance suppression.

Description

Technical Field

[0001] This application relates to the field of motor control technology, specifically to a control method for a servo motor, a servo driver, and a servo system. Background Technology

[0002] In eddy current spinning servo systems, notch filters can be used to quickly detect and suppress the mechanical resonance of servo motors through frequency estimation algorithms. However, aging of the synchronous belt or changes in ambient temperature and humidity in the servo system can cause the resonant frequency to drift, causing the notch filter to fail, thus leading to the failure of the detection and suppression of mechanical resonance of the servo motor. Summary of the Invention

[0003] The main objective of this application is to provide a servo motor control method, servo driver, and servo system, which aims to at least partially solve the aforementioned technical problems.

[0004] Firstly, a method for controlling a servo motor is provided, comprising the following steps: Obtain the servo motor's speed command and actual angular velocity; Based on the speed command, the theoretical angular velocity of the servo motor is determined, and the vibration signal is obtained based on the deviation between the actual angular velocity and the theoretical angular velocity. The speed command of the servo motor is adjusted by using vibration signals to obtain the target speed command; Control the servo motor to run according to the target speed command.

[0005] Optionally, the theoretical angular velocity of the servo motor is determined based on the speed command, including: The theoretical torque is obtained based on the speed command; The theoretical angular acceleration is obtained based on the theoretical torque and the moment of inertia of the servo motor. The theoretical angular velocity is obtained based on the theoretical angular acceleration and historical deviation feedback. The historical deviation feedback is the deviation between the historical actual angular velocity and the historical theoretical angular velocity in the previous control cycle before the current control cycle.

[0006] Optionally, the theoretical torque is obtained based on the speed command, including: The theoretical torque is obtained based on the speed command, speed command feedforward, and historical vibration signal, where the historical vibration signal is the vibration signal obtained in the previous control cycle.

[0007] Optionally, the speed command of the servo motor is adjusted using vibration signals to obtain the target speed command, including: The vibration signal is filtered to obtain the target vibration signal; Vibration suppression feedback is obtained based on the target vibration signal and damping gain; The speed command is adjusted using vibration suppression feedback to obtain the target speed command.

[0008] Optionally, vibration suppression feedback is obtained based on the target vibration signal and damping gain, including: Extract the main resonant frequency of the target vibration signal; Compare the main resonant frequency with a preset frequency threshold; When the main resonant frequency is greater than the preset frequency threshold, the damping gain is adjusted to obtain the first damping gain. Vibration suppression feedback is obtained based on the target vibration signal and the first damping gain.

[0009] Optionally, vibration suppression feedback is obtained based on the target vibration signal and damping gain, including: Extract the resonance amplitude of the target vibration signal; Compare the resonant amplitude with a preset amplitude threshold; When the resonant amplitude is greater than the preset amplitude threshold, the damping gain is adjusted to obtain the second damping gain; Vibration suppression feedback is obtained based on the target vibration signal and the second damping gain.

[0010] Optionally, the servo motor is used to drive the traverse mechanism, and the speed command and actual angular velocity of the servo motor are obtained, including: Based on the stroke and speed planning of the traverse mechanism, a motion curve is generated. This motion curve includes a constant speed segment, a deceleration segment, and an acceleration segment. The constant speed segment includes a first and second constant speed segment starting from the center point of the stroke planning, and a third and fourth constant speed segment ending at the center point. The deceleration segment includes a first and second deceleration segment ending at the boundary point of the stroke planning. The acceleration segment includes a first and second acceleration segment starting at the boundary point. Based on the motion curve, a position command is obtained. Based on the position command, a speed command is obtained. The position command is obtained based on the motion curve; Based on the position command, obtain the speed command.

[0011] Optionally, the servo motor's speed command and actual angular velocity are obtained, including: The encoder signal of the servo motor is acquired, wherein the encoder signal is obtained by the incremental encoder at the shaft end of the servo motor. The actual angular velocity is calculated based on the rise time of two consecutive pulses of the encoder signal and the number of pulses per revolution of the incremental encoder.

[0012] Secondly, a servo driver is also provided, including a memory and a processor, wherein a computer program is stored in the memory, and the computer program, when executed by the processor, implements any of the methods described above.

[0013] Thirdly, a servo system is also provided, including a servo driver, a servo motor and a traverse mechanism connected in sequence as described above; The servo driver is used to control the servo motor to drive the traverse mechanism to work according to the preset stroke and speed plan.

[0014] Through the above technical solution, this application includes at least the following beneficial technical effects: This application first monitors the actual angular velocity of the servo motor and obtains its theoretical angular velocity based on the servo motor's speed command. Then, based on the deviation between the actual and theoretical angular velocities, a vibration signal is obtained to adjust the servo motor's speed command, thereby controlling the servo motor's operation through the adjusted target speed command. Since the vibration signal can characterize the low-frequency vibration characteristics of the servo motor and is not affected by the resonant frequency shift, controlling the servo motor's operation through the adjusted target speed command can suppress mechanical resonance during servo motor operation. Compared to using a notch filter to achieve resonance suppression in the servo system, this improves the reliability of the servo motor control method in terms of resonance suppression. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the structure of the servo system provided in an exemplary embodiment of this application; Figure 2 This is a flowchart illustrating a servo motor control method provided in an exemplary embodiment of this application; Figure 3 This is a state control block diagram of a servo motor provided in an exemplary embodiment of this application; Figure 4 This is a diagram showing the operating curve of the traverse mechanism provided in an exemplary embodiment of this application; Figure 5 This is another schematic flowchart of the servo motor control method provided in an exemplary embodiment of this application; Figure 6 This is a schematic diagram of the structure of a servo driver provided in an exemplary embodiment of this application.

[0017] The realization of the objectives, functional features and advantages of the embodiments of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0018] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0019] In the description of this application, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0020] Additionally, in this application, the term "exemplary" is used to mean "used as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to implement and use this application. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that this application can be implemented without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of this application with unnecessary detail. Therefore, this application is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.

[0021] First, the background technology involved in the embodiments of this application will be described in detail.

[0022] Specifically, in vortex spinning traverse servo systems, due to the extremely high winding speed, the traverse guide must undergo high-frequency reciprocating motion to spread the yarn across the entire width of the package in a very short time, preventing accumulation at any point. Therefore, the smoothness of the traverse motion of the traverse guide is crucial. Any minute vibration or impact will be amplified at high speeds, leading to sudden changes in yarn tension and even yarn breakage. To meet the rapid displacement requirements of the traverse guide, servo drives often increase the speed loop gain. However, high gain easily induces speed vibration and mechanical resonance (low-frequency vibration in the 100-1000Hz range), especially when the servo system has a dual-inertia structure, synchronous belt drive, and elastic connection. In addition, mechanical structures such as guide rails and gears, the uniformity of the fiber sliver itself during the drafting process in the preceding stage, random changes in yarn tension at high speeds, and nonlinear factors such as friction introduce random noise, further increasing the instability of the servo system under high-speed operation.

[0023] In related technologies, notch filters, input shaping, and disturbance observers (DOBs) are used to suppress vibration in servo systems. However, the resonant frequency drift of the servo system can cause notch filters to fail; input shaping increases response delay and is ineffective against unknown disturbances; traditional DOBs tend to use a nominal inverse model, which, due to its differentiator, increases the system's sensitivity to noise from vibration signals. Therefore, notch filters, input shaping, and disturbance observers all suffer from reliability issues.

[0024] Therefore, this application provides a servo motor control method, servo driver, and servo system. First, the actual angular velocity of the servo motor is monitored, and the theoretical angular velocity of the servo motor is obtained based on the servo motor's speed command. Then, based on the deviation between the actual and theoretical angular velocities, a vibration signal is obtained to adjust the servo motor's speed command, thereby controlling the servo motor's operation through the adjusted target speed command. Since the vibration signal can characterize the low-frequency vibration characteristics of the servo motor, and the vibration signal is not affected by resonant frequency shifts, controlling the servo motor's operation through the adjusted target speed command can suppress mechanical resonance during servo motor operation. Compared to using a notch filter to achieve resonance suppression in the servo system, this improves the reliability of the servo motor control method in terms of resonance suppression. Furthermore, compared to using input shaping for resonance suppression, it does not introduce response delay. The vibration signal includes all vibrations of the servo system, enabling the perception of unknown disturbances. In addition, the damping gain in the disturbance observer provided in this application can be adjusted according to the magnitude of the vibration signal's influence, avoiding increasing the system's noise sensitivity to the vibration signal.

[0025] The servo system provided in the embodiments of this application will be described in detail below.

[0026] Firstly, this embodiment provides a servo system, such as... Figure 1 As shown, the servo system may include a servo driver, a servo motor, and a traverse mechanism connected in sequence. The servo driver controls the servo motor to drive the traverse mechanism to operate according to a preset stroke and speed plan.

[0027] In this embodiment, the servo system can be an eddy current spinning traverse servo system, and the traverse mechanism can be a traverse yarn guide. The traverse yarn guide and the servo motor are connected via a flexible transmission component such as a synchronous belt. The servo driver can receive parameters sent from the user terminal and generate position commands; then, based on the position commands, it generates real-time speed commands to control the servo motor to operate. Through synchronous belt transmission, it precisely controls the yarn guide to perform high-speed reciprocating traverse yarn guiding actions. The user terminal can include a host computer or an HMI (Human Machine Interface). The specific structure of the servo driver is described in the following implementation method.

[0028] Based on this, secondly, this embodiment provides a servo motor control method, such as... Figure 2 As shown, it includes the following steps: S201: Obtain the servo motor's speed command and actual angular velocity. In this embodiment, the servo motor control method can be executed by a servo driver. The servo motor control loop in the servo driver can include a position loop, a speed loop, and a current loop. Through the position loop, the position command can be converted into a real-time speed command. Furthermore, the servo driver can extract the actual angular velocity from the running feedback signal during the servo motor's operation following the speed command. The running feedback signal can include the servo motor's actual speed signal and actual position signal, etc. The position command can be determined based on the running curve of the transverse yarn guide.

[0029] S202: Based on the speed command, determine the theoretical angular velocity of the servo motor, and obtain the vibration signal based on the deviation between the actual angular velocity and the theoretical angular velocity. In this embodiment, the actual angular velocity may include the ideal angular velocity component determined by the speed command and the vibration component caused by mechanical resonance. Therefore, the theoretical angular velocity can be determined based on the motor's speed command; then, the vibration component is extracted as the vibration signal based on the deviation between the actual angular velocity and the theoretical angular velocity. The vibration signal and the theoretical angular velocity can be estimated using different observers based on different state estimates in the servo motor's control loop.

[0030] S203: The vibration signal is used to adjust the speed command of the servo motor to obtain the target speed command. In this embodiment, the vibration signal and the speed command can be superimposed in the control circuit of the servo motor to obtain the target speed command.

[0031] S204: Control the servo motor to run according to the target speed command. In this embodiment, the servo driver can input the target speed command into the control loop of the servo motor, obtain the angular velocity control command through the speed loop and the current loop in sequence, and send the angular velocity control command to the servo motor to control the servo motor to run according to the angular velocity control command.

[0032] Next, other possible implementation methods for controlling the servo motor will be described.

[0033] In some specific implementations, step S202 may include: obtaining the theoretical torque according to the speed command; obtaining the theoretical angular acceleration according to the theoretical torque and the moment of inertia of the servo motor; and obtaining the theoretical angular velocity according to the theoretical angular acceleration and historical deviation feedback. The historical deviation feedback refers to the deviation between the historical actual angular velocity and the historical theoretical angular velocity in the previous control cycle prior to the current control cycle.

[0034] In this embodiment, the actual angular velocity and theoretical torque can be used as observations in the control loop of the servo motor and input into a Luneburger observer. Based on the second-order nominal model of the servo motor and the input theoretical torque, the Luneburger observer dynamically estimates the theoretical angular velocity of the servo system in an ideal state without resonance disturbance in real time. Then, the actual angular velocity is compared with the estimated theoretical angular velocity to obtain the vibration signal. The vibration signal accurately captures the real-time vibration state of the servo system, and the resonance amplitude of the vibration signal directly reflects the intensity of the resonance. The dominant frequency component of the vibration signal is the main resonant frequency of the servo system. It should be noted that the state-space equation of the servo system can be expressed as:

[0035] ; in,

[0036]

[0037] x = ω; ω is the estimated angular velocity state value in the control loop, y is the angular velocity control command output by the control loop, A is the system matrix, B is the input matrix, and T is the system matrix. e Where is the theoretical torque, and J is the moment of inertia.

[0038] Therefore, as Figure 3 As shown, the Romberg observer can be represented as:

[0039] ; in, For the angular velocity state estimate of the Luneburger observer, L=[K s ] represents the gain matrix of the Luneburg observer.

[0040] In the specific implementation, the theoretical torque T e The actual angular velocity ω is input into the Luneburg observer, which then calculates the theoretical torque T. e The theoretical angular acceleration is estimated by considering the rotational inertia J of the servo motor; then, the theoretical angular acceleration and historical deviation are fed back. After superposition, the theoretical angular acceleration is obtained; and by integrating the theoretical angular acceleration, the theoretical angular velocity can be obtained. Finally, based on the actual angular velocity and the theoretical angular velocity... The deviation between them is used to obtain the vibration signal.

[0041] In some specific implementations, the theoretical torque can be obtained by: obtaining the theoretical torque based on a speed command, speed command feedforward, and historical vibration signals. The historical vibration signals are the vibration signals obtained in the previous control cycle. For example... Figure 3 As shown, the control loop can also incorporate speed command feedforward. Increase the speed ring's speed command V P Tracking performance.

[0042] In some implementations, step S203 may include: filtering the vibration signal to obtain a target vibration signal; obtaining vibration suppression feedback based on the target vibration signal and damping gain; and adjusting the rotational speed command using the vibration suppression feedback to obtain a target rotational speed command.

[0043] In this embodiment, the vibration signal e(k), where k is the number of samples, extracted by the Luneburger observer, can be further filtered and shaped by a disturbance observer to obtain the target vibration signal. Vibration suppression feedback is then obtained through appropriate damping gain and fed back to the velocity loop. For example... Figure 3 As shown, the disturbance observer may include a first-order low-pass filter unit and a damping gain unit, or it may include a first-order low-pass filter unit, a high-pass filter unit, and a damping gain unit. The transfer function of the first-order low-pass filter unit can be: ; T lpf Let be the time constant of the first-order low-pass filter unit, and s be the complex frequency of the servo system. The transfer function of the first-order low-pass filter unit is discretized using the backward difference method, yielding the difference equation:

[0044] ; K lpf X is the low-pass filter coefficient. lpf This is the vibration signal after low-pass filtering.

[0045] In addition, the transfer function of the high-pass filter unit can be: ; T hpf Let be the time constant of the high-pass filter unit. Similarly, by discretizing the transfer function of the high-pass filter unit using the backward difference method, we can obtain the difference equation:

[0046] ; K hpf X is the high-pass filter coefficient. hpf The vibration signal is after high-pass filtering, T s is the time constant of the filter in the velocity loop.

[0047] Therefore, the vibration signal e(k) extracted from the Romberg observer, after being filtered by a low-pass filter unit or a combination of a low-pass filter unit and a high-pass filter unit to remove high-frequency noise, is multiplied by a damping gain K. d The final vibration suppression feedback V can then be obtained. vff (k). In specific implementation, when the filter unit of the disturbance observer is a first-order low-pass filter unit, the vibration suppression feedback V vff (k) is as follows: ; When the disturbance observer's filtering unit includes a first-order low-pass filter unit and a high-pass filter unit, the vibration suppression feedback V vff (k) is as follows: .

[0048] Therefore, as Figure 3 As shown, the target speed command V cmd (k)=V p (k)+V ff (k)+V vff (k).

[0049] It should be noted that the parameters (K) in the Romberg observer and the perturbation observer... s T lpf T hpf K lpf K hpf K dThe initial value of the servo motor can be sent from the user terminal to the servo driver. Furthermore, during the control of the servo motor, each physical quantity in the control loop needs to be standardized and calibrated according to its actual unit in the program (e.g., rotational speed: 0.0001 rpm, time: ns), and converted into an integer in Q24 format or other formats for calculation.

[0050] In one specific implementation, obtaining vibration suppression feedback may include: extracting the main resonant frequency of the target vibration signal; comparing the main resonant frequency with a preset frequency threshold; adjusting the damping gain when the main resonant frequency is greater than the preset frequency threshold to obtain a first damping gain; and obtaining vibration suppression feedback based on the target vibration signal and the first damping gain. In this embodiment, the servo driver can also adaptively adjust the damping gain based on the target vibration signal to limit the amplitude and rate of the vibration suppression feedback, preventing high-frequency measurement noise from being amplified and ensuring system robustness. Specifically, the servo driver can use a radix-2 FFT algorithm to extract the main resonant frequency of the target vibration signal. When the main resonant frequency is greater than the preset frequency threshold, the damping gain is reduced or damping gain compensation is paused to obtain the first damping gain. The preset frequency threshold can be a safety threshold set according to the actual safety requirements of the servo system. The adjustment value of the damping gain can be determined based on the frequency deviation between the main resonant frequency and the preset frequency threshold. When the frequency deviation is large, the adjustment value is increased; when the frequency deviation is small, the adjustment value is decreased.

[0051] It should be noted that the servo driver can also perform spectral analysis on the target vibration signal, extracting the top resonant frequencies with the highest amplitudes; based on the deviation of each resonant frequency from its corresponding preset threshold, different damping gain weights are assigned to generate a multimode weight matrix; the damping gain is then adjusted in stages using the multimode weight matrix to obtain the first damping gain. The damping gain weight corresponding to the primary resonant frequency is higher than that of the secondary resonant frequency.

[0052] Furthermore, the servo drive can also predict deviation feedback based on historical deviation feedback from multiple historical control cycles; the damping gain can then be adjusted according to this predicted deviation feedback. For example, when the absolute value of the predicted deviation feedback is greater than a preset deviation threshold, the damping gain can be increased by 15%-30% in advance to achieve resonance pre-suppression. The preset deviation threshold and the adjusted values ​​of the damping gain can be obtained experimentally.

[0053] In another specific embodiment, obtaining vibration suppression feedback may include: extracting the resonant amplitude of the target vibration signal; comparing the resonant amplitude with a preset amplitude threshold; adjusting the damping gain when the resonant amplitude is greater than the preset amplitude threshold to obtain a second damping gain; and obtaining vibration suppression feedback based on the target vibration signal and the second damping gain. In this embodiment, the servo driver can use a radix-2 FFT algorithm to extract the resonant amplitude of the target vibration signal. When the resonant amplitude is greater than the preset amplitude threshold, the damping gain is reduced or damping gain compensation is paused to obtain the second damping gain. The preset amplitude threshold can be a safety threshold set according to the actual safety requirements of the servo system. The adjustment value of the damping gain can be determined based on the amplitude deviation between the resonant amplitude and the preset amplitude threshold. When the frequency deviation is large, the adjustment value is increased; when the frequency deviation is small, the adjustment value is decreased.

[0054] In some specific embodiments, the method for obtaining the speed command in step S201 may include: generating a motion curve based on the stroke planning and speed planning of the traverse mechanism. The motion curve includes a constant speed segment, a deceleration segment, and an acceleration segment. The constant speed segment includes a first and a second constant speed segment starting from the center point of the stroke planning, and a third and a fourth constant speed segment ending at the center point. The deceleration segment includes a first and a second deceleration segment ending at the boundary point of the stroke planning. The acceleration segment includes a first and a second acceleration segment starting from the boundary point. A position command is obtained based on the motion curve. A speed command is obtained based on the position command.

[0055] In this embodiment, the stroke planning and speed planning of the traverse mechanism are sent from the user terminal to the servo driver. The stroke planning may include stroke width, anti-overlap width, braking ratio, and commutation ratio, while the speed planning may include operating speed range and anti-overlap speed. Figure 4As shown, the servo driver can generate eight motion curves based on stroke planning and speed planning. The center point of the stroke planning is the midpoint of the stroke width in the width direction, and the boundary points of the stroke planning can include the first boundary point and the second boundary point of the stroke width in the width direction. The first uniform speed segment 1 and the second uniform speed segment 5 of the motion curve start from the center point, and the third uniform speed segment 4 and the fourth uniform speed segment 8 end at the center point. Within the first uniform speed segment 1, the second uniform speed segment 5, the third uniform speed segment 4, and the fourth uniform speed segment 8, the traverse mechanism runs at a constant speed. The first deceleration segment 2 ends at the first boundary point, and the second deceleration segment 6 ends at the second boundary point. In the first deceleration segment 2 and the second deceleration segment 6, the traverse mechanism gradually approaches the boundary point of the stroke width, thereby decelerating. The running speed of the traverse mechanism gradually decreases to zero, and it reverses direction after reaching the boundary point of the stroke width. The first acceleration segment 3 starts from the first boundary point, and the second acceleration segment 7 starts from the second boundary point. Within the first acceleration segment 3 and the second acceleration segment 7, after the traverse mechanism reverses direction, the running speed of the traverse mechanism gradually accelerates from zero to a constant speed. It is understandable that after obtaining the motion curve of the traverse mechanism, the position command within each control cycle can be obtained by sampling the motion curve according to the control cycle of the servo motor. Then, the position command is input into the position loop, and the speed command within each control cycle can be output.

[0056] In some specific embodiments, the method for obtaining the actual angular velocity in step S201 may include: acquiring the encoder signal of the servo motor. The encoder signal is obtained by an incremental encoder at the shaft end of the servo motor. The actual angular velocity is calculated based on the rise time of two consecutive pulses of the encoder signal and the number of pulses per revolution of the incremental encoder. In this embodiment, the encoder signal output by the incremental encoder may include A-phase, B-phase, and Z-phase signals. The servo driver may use the M / T tachometer method, capturing the rise time of two consecutive pulses of the A-phase or B-phase signal through a high-speed timing unit, and calculating the instantaneous angular velocity by combining this with the number of pulses per revolution (PPR) of the incremental encoder to obtain the actual angular velocity.

[0057] In a specific example, such as Figure 5As shown, the overall control process of the servo system can include: the user sets the parameters of the control loop on the host computer or HMI and sends them to the servo driver; the servo driver receives the parameters from the host computer or HMI, generates an eight-segment motion curve of the transverse yarn guide based on the parameters, and determines the position and speed commands; then, it controls the servo motor to start running, drives the transverse yarn guide to start working, and acquires the encoder signal of the servo motor (which may include position feedback or current feedback), calculates the actual angular velocity, and inputs it into the Luneburg observer; then, it estimates the theoretical angular velocity through the Luneburg observer, combines it with the actual angular velocity to obtain vibration suppression feedback, and feeds it back to the speed loop of the control loop to adjust the speed command. In addition, the servo driver can also calculate the main resonant frequency and resonant amplitude of the vibration signal, perform vibration anomaly detection, trigger a fault handling program when a vibration anomaly is detected, and save the fault record for fault analysis. The servo driver can also feed back the main resonant frequency and resonant amplitude to the host computer, allowing the host computer to monitor the driver alarm in real time and perform real-time operation status monitoring.

[0058] Secondly, such as Figure 6 As shown, this embodiment provides a servo driver, which may include a memory and a processor. The memory stores a computer program, and when the computer program is executed by the processor, it implements the method as described in any of the above embodiments. The servo driver may include components such as a processor 601 with one or more processing cores, a memory 602 with one or more computer-readable storage media, a power supply 603, and an input unit 604. Those skilled in the art will understand that... Figure 6 The structure of the servo drive shown is not intended to limit the servo drive; it may include more or fewer components than shown, or combine certain components, or have different component arrangements. The processor 601 is the control center of the servo drive, connecting various parts of the servo drive via various interfaces and lines. It performs various functions and processes data by running or executing software programs and / or modules stored in memory 602, and by calling data stored in memory 602, thereby providing overall monitoring of the servo drive. Optionally, the processor 601 may include one or more processing cores; preferably, the processor 601 may integrate an application processor and a modem processor, wherein the application processor mainly handles the operating system, user interface, and computer programs, and the modem processor mainly handles wireless communication. It is understood that the modem processor may not be integrated into the processor 601.

[0059] The memory 602 can be used to store software programs and modules. The processor 601 executes various functional applications and data processing by running the software programs and modules stored in the memory 602. The memory 602 may mainly include a program storage area and a data storage area. The program storage area may store the operating system, computer programs required for at least one function (such as position command acquisition function, speed command acquisition function, etc.), etc.; the data storage area may store data created according to the use of the server (such as motion curves, extracted vibration signals, the main resonant frequency and resonant amplitude of the target vibration signal, etc.). In addition, the memory 602 may include high-speed random access memory, and may also include non-volatile memory, such as at least one disk storage device, flash memory device, or other volatile solid-state storage device. Accordingly, the memory 602 may also include a memory controller to provide the processor 601 with access to the memory 602.

[0060] The servo driver also includes a power supply 603 that supplies power to the various components. Preferably, the power supply 603 can be logically connected to the processor 601 through a power management system, thereby enabling functions such as charging, discharging, and power consumption management through the power management system. The power supply 603 may also include one or more DC or AC power supplies, recharging systems, power fault detection circuits, power converters or inverters, power status indicators, and other arbitrary components.

[0061] The servo drive may also include an input unit 604, which can be used to receive input digital or character information, and generate keyboard, mouse, joystick, optical or trackball signal inputs related to user settings and function control.

[0062] Although not shown, the servo driver may also include a display unit, etc., which will not be described in detail here. Specifically, in this embodiment, when the servo driver executes the servo motor control method, the processor 601 in the servo driver will load the executable files corresponding to the processes of one or more computer programs into the memory 602 according to the instructions as described above, and the processor 601 will run the computer programs stored in the memory 602 to execute the electrical equipment status detection method as described in any of the above embodiments.

[0063] Fourthly, this embodiment provides a computer-readable storage medium having a computer program stored thereon, the computer program being loaded by a processor to perform the steps in the method of any of the above embodiments.

[0064] It will be understood by those skilled in the art that any references to memory, storage, database, or other media used in the embodiments provided in this invention may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM), or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), dual data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), Synchlink, SLDRAM, RAMbus direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and RAMbus dynamic RAM (RDRAM), etc.

[0065] Since the computer program stored in the storage medium can execute the steps in the servo motor control method in any embodiment of the present invention, the beneficial effects that the servo motor control method in any embodiment of the present invention can achieve can be realized, as detailed in the preceding embodiments, and will not be repeated here.

[0066] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0067] The foregoing has provided a detailed description of the electrical equipment status detection method and device provided in the embodiments of this application. Specific examples have been used to illustrate the principles and implementation methods of this application. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of this application. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of this application. Therefore, the content of this specification should not be construed as a limitation of this application.

[0068] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

Claims

1. A control method for a servo motor, characterized in that, include: Obtain the servo motor's speed command and actual angular velocity; Based on the rotation speed command, the theoretical angular velocity of the servo motor is determined, and the vibration signal is obtained based on the deviation between the actual angular velocity and the theoretical angular velocity. The vibration signal is used to adjust the rotational speed command of the servo motor to obtain the target rotational speed command; The servo motor is controlled to operate according to the target speed command.

2. The servo motor control method according to claim 1, characterized in that, Determining the theoretical angular velocity of the servo motor based on the rotation speed command includes: The theoretical torque is obtained based on the stated rotational speed command; The theoretical angular acceleration is obtained based on the theoretical torque and the moment of inertia of the servo motor. The theoretical angular velocity is obtained based on the theoretical angular acceleration and historical deviation feedback, wherein the historical deviation feedback is the deviation between the historical actual angular velocity and the historical theoretical angular velocity in the previous control cycle before the current control cycle.

3. The servo motor control method according to claim 2, characterized in that, The step of obtaining the theoretical torque according to the speed command includes: The theoretical torque is obtained based on the speed command, speed command feedforward, and historical vibration signal, wherein the historical vibration signal is the vibration signal obtained in the previous control cycle.

4. The servo motor control method according to claim 1, characterized in that, The step of adjusting the speed command of the servo motor using the vibration signal to obtain the target speed command includes: The vibration signal is filtered to obtain the target vibration signal; Based on the target vibration signal and damping gain, vibration suppression feedback is obtained; The vibration suppression feedback is used to adjust the rotational speed command to obtain the target rotational speed command.

5. The servo motor control method according to claim 4, characterized in that, The step of obtaining vibration suppression feedback based on the target vibration signal and damping gain includes: Extract the main resonant frequency of the target vibration signal; The main resonant frequency is compared with a preset frequency threshold. When the main resonant frequency is greater than the preset frequency threshold, the damping gain is adjusted to obtain the first damping gain; The vibration suppression feedback is obtained based on the target vibration signal and the first damping gain.

6. The servo motor control method according to claim 4, characterized in that, The step of obtaining vibration suppression feedback based on the target vibration signal and damping gain includes: Extract the resonance amplitude of the target vibration signal; The resonance amplitude is compared with a preset amplitude threshold. When the resonance amplitude is greater than the preset amplitude threshold, the damping gain is adjusted to obtain a second damping gain; The vibration suppression feedback is obtained based on the target vibration signal and the second damping gain.

7. The servo motor control method according to claim 1, characterized in that, The servo motor is used to drive the traverse mechanism. The acquisition of the servo motor's rotational speed command and actual angular velocity includes: Based on the stroke planning and speed planning of the traverse mechanism, a motion curve is generated, wherein the motion curve includes a uniform speed running segment, a deceleration running segment, and an acceleration running segment. The uniform speed running segment includes a first uniform speed segment and a second uniform speed segment starting from the center point of the stroke planning, and a third uniform speed segment and a fourth uniform speed segment ending at the center point. The deceleration running segment includes a first deceleration segment and a second deceleration segment ending at the boundary point of the stroke planning. The acceleration running segment includes a first acceleration segment and a second acceleration segment starting from the boundary point. Based on the motion curve, the position command is obtained; The rotation speed command is obtained based on the position command.

8. The servo motor control method according to claim 1, characterized in that, The acquisition of the servo motor's speed command and actual angular velocity includes: The encoder signal of the servo motor is acquired, wherein the encoder signal is detected by an incremental encoder at the shaft end of the servo motor. The actual angular velocity is calculated based on the rise time of two consecutive pulses of the encoder signal and the number of pulses per revolution of the incremental encoder.

9. A servo driver, characterized in that, It includes a memory and a processor, wherein the memory stores a computer program that, when executed by the processor, implements the method as described in any one of claims 1-8.

10. A servo system, characterized in that, Includes the servo driver, servo motor, and traverse mechanism as described in claim 9, connected in sequence; The servo driver is used to control the servo motor to drive the traverse mechanism to work according to the preset stroke and speed plan.

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