Torque ripple suppression method and device

Abstract

The present application relates to the field of communication, in particular to a torque pulsation suppression method and device, wherein for non-complementary motors, compensation current is directly injected to reduce vibration; for complementary motors, the first total power consumed when each complementary motor is compensated by current alone is estimated, and the second total power consumed when the complementary motors are cooperatively compensated by current considering the vibration consumption reduction of the complementary motors is estimated, the first total power and the second total power are compared, and the compensation current is injected to the complementary motors in a way that the corresponding total power is smaller to cooperatively adjust the vibration of the complementary motors; in the present application, the complementary motors in a multi-motor device can be identified, and the total power consumed when the complementary motors are cooperatively compensated and when the complementary motors are compensated by current alone is compared, so that the compensation current is injected to the complementary motors in a way that the total power consumed is smaller, avoiding the problem of excessive energy consumption caused by the injection of compensation current, and saving energy.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of communication, in particular to a torque pulsation suppression method and device. BACKGROUND

[0002] When the motor is running, due to the existence of the stator teeth and the rotor magnetic steel, the relative position between the stator teeth and the rotor magnetic steel changes constantly when the rotor rotates. When the center of the magnetic steel and the tooth is aligned, the magnetic resistance is small; while when they are misaligned, the magnetic resistance is large. The change of the magnetic resistance will cause the change of the magnetic flux, thereby causing the fluctuation of the motor current, thereby generating torque pulsation, causing the motor to vibrate;

[0003] The prior art usually compensates for the fluctuation of the current by injecting a compensation current into the motor, thereby suppressing the torque pulsation to reduce the vibration amplitude of the motor; for multi-motor equipment (such as numerical control machine tools, multi-axis machining equipment, etc.), in order to reduce the overall vibration of the equipment, the prior art injects a compensation current into each motor respectively, so that the vibration of each motor is reduced, thereby reducing the overall vibration of the equipment. This method controls the vibration of each motor as an independent motor, without considering the mutual consumption effect between different motor vibrations, which is prone to cause the problem of excessive total power injection, which is not conducive to energy saving. SUMMARY

[0004] Therefore, it is necessary to provide a torque pulsation suppression method and device in view of the above problems.

[0005] The embodiment of the present application is implemented in the following manner: a torque pulsation suppression method is provided, which comprises:

[0006] S1: monitoring the motor vibration and the corresponding current fluctuation of each motor in the multi-motor equipment;

[0007] S2: determining the vibration direction of each motor in space according to the position of each motor, determining the complementary motor group according to the vibration direction, and determining the motor not in the complementary motor group as an independent motor;

[0008] S3: for each independent motor, injecting a compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so that the motor vibration is reduced to below a preset amplitude;

[0009] S4: for each pair of complementary motors in each complementary motor group, determining the total power injected under the condition that a compensation current is injected into each complementary motor separately, and determining the total power as a first total power, wherein the injection of the compensation current into each complementary motor separately reduces the vibration of the complementary motor to below a preset amplitude;

[0010] S5: determining that the total amount of injected electric quantity in the case of injecting compensation current to the two complementary motors cooperatively is a second total amount of electric quantity, wherein, after injecting compensation current to the two complementary motors cooperatively, the motor vibration generated by each two complementary motors cancels out each other, and the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0011] S6: judging whether the first total amount of electric quantity is greater than the second total amount of electric quantity, if not, injecting compensation current to each complementary motor individually, and if yes, injecting compensation current to the two complementary motors cooperatively.

[0012] In one embodiment, the present application provides a torque ripple suppression device, the device comprising:

[0013] a monitoring module for monitoring the motor vibration of each motor in the multi-motor device and the corresponding current fluctuation;

[0014] a first processing module for determining the vibration direction of each motor in space according to the position of each motor, determining the complementary motor group according to the vibration direction, and determining the motor not in the complementary motor group as an independent motor;

[0015] a second processing module for, for each independent motor, injecting compensation current to the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so as to reduce the motor vibration to below a preset amplitude;

[0016] a third processing module for, for each two complementary motors in each complementary motor group, determining the total amount of injected electric quantity in the case of injecting compensation current to each complementary motor individually, and determining the total amount of injected electric quantity as a first total amount of electric quantity, wherein, injecting compensation current to each complementary motor individually reduces the vibration of the complementary motor to below a preset amplitude;

[0017] a fourth processing module for determining that the total amount of injected electric quantity in the case of injecting compensation current to the two complementary motors cooperatively is a second total amount of electric quantity, wherein, after injecting compensation current to the two complementary motors cooperatively, the motor vibration generated by each two complementary motors cancels out each other, and the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0018] a fifth processing module for judging whether the first total amount of electric quantity is greater than the second total amount of electric quantity, if not, injecting compensation current to each complementary motor individually, and if yes, injecting compensation current to the two complementary motors cooperatively.

[0019] The application provides a torque ripple suppression method, which comprises the following steps: monitoring the motor vibration and the corresponding current fluctuation of each motor in a multi-motor device; determining the vibration direction of each motor in space according to the position of each motor, determining the complementary motor group according to the vibration direction, and determining the motor not in the complementary motor group as an independent motor; for each independent motor, injecting a compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so as to reduce the motor vibration to below a preset amplitude; for each complementary motor in each complementary motor group, determining the total power injected under the condition that a compensation current is injected into each complementary motor separately, and determining the total power as a first total power; determining the total power injected under the condition that a compensation current is injected into the two complementary motors cooperatively as a second total power; judging whether the first total power is greater than the second total power, if not, injecting a compensation current into each complementary motor separately, and if yes, injecting a compensation current into the two complementary motors cooperatively; in the application, the complementary motor in the multi-motor device can be identified, and the total power consumption under the two modes of cooperative current compensation and separate current compensation of the complementary motor is compared and contrasted, so that the compensation current injection of the complementary motor is performed in a smaller power consumption mode, the problem of excessive power consumption of the injected compensation current is avoided, and energy is saved. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 A flow chart of the torque ripple suppression method provided in an embodiment;

[0021] Figure 2 An application environment diagram of the torque ripple suppression method provided in an embodiment;

[0022] Figure 3 A subsequent curve diagram of the current curve of the torque ripple suppression method provided in an embodiment;

[0023] Figure 4 A module flow chart of the torque ripple suppression method provided in an embodiment;

[0024] Figure 5 An internal structure block diagram of the computer device in an embodiment. DETAILED DESCRIPTION

[0025] In order to make the objectives, technical solutions and advantages of the application clearer, the application is further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the application, and are not used to limit the application.

[0026] It is to be understood that the terms "first", "second", and the like used herein can be used to describe various elements, but are not limited to these terms in this context. These terms are only used to distinguish one element from another. For example, a first xx script can be termed a second xx script, and, similarly, a second xx script can be termed a first xx script, without departing from the scope of the present application.

[0027] As shown in FIG. 1, in one embodiment, a torque ripple suppression method is proposed, which comprises: Figure 1

[0028] S1: monitoring the motor vibration and the corresponding current fluctuation of each motor in the multi-motor device;

[0029] S2: determining the vibration direction of each motor in the space according to the position of each motor, determining the complementary motor group according to the vibration direction, and determining the motor not in the complementary motor group as an independent motor;

[0030] S3: for each independent motor, injecting a compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so as to reduce the motor vibration to below a preset amplitude;

[0031] S4: for each pair of complementary motors in each complementary motor group, determining the total amount of electricity injected in the case of injecting a compensation current into each complementary motor separately, and determining the total amount of electricity as a first total amount of electricity, wherein injecting a compensation current into each complementary motor separately reduces the vibration of the complementary motor to below a preset amplitude;

[0032] S5: determining the total amount of electricity injected in the case of injecting a compensation current into the two complementary motors cooperatively, wherein after injecting a compensation current into the two complementary motors cooperatively, the motor vibrations generated by each of the two complementary motors cancel each other out, so that the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0033] S6: determining whether the first total amount of electricity is greater than the second total amount of electricity, if not, injecting a compensation current into each complementary motor separately, and if yes, injecting a compensation current into the two complementary motors cooperatively.

[0034] In this embodiment, as shown in FIG. 2, the torque ripple suppression method comprises: Figure 2 ​As shown, the method is executed in a computer device, which can be a standalone physical server or terminal, a server cluster composed of multiple physical servers, a cloud server providing basic cloud computing services such as cloud server, cloud database, cloud storage and CDN, etc. Each motor of the multi-motor device is controlled by the computer device, and a motor drive circuit is arranged in the motor. Various sensors (such as current sensors, vibration sensors, etc.) are equipped in the circuit for monitoring the running state of the motor. These sensors can communicate with the computer device and then transmit the monitoring data to the computer device. A power module (such as an IGBT module) controlled by the computer device is arranged in the drive circuit. The computer device can calculate the current to be compensated by monitoring the data, and then adjust the power module to inject the compensation current into the motor winding, so as to suppress the torque ripple of the motor and stabilize the operation of the motor.

[0035] In this embodiment, for each motor, the current sensor monitors the current in the motor in real time during the operation of the motor, and transmits the monitored current to the computer device. The vibration sensor monitors the vibration of the motor in real time, and transmits the monitored vibration data to the computer device. Then the computer device can generate a current curve representing the current fluctuation (the horizontal coordinate is time, and the vertical coordinate is current), and a vibration curve representing the vibration of the motor (the horizontal coordinate of the vibration curve is time, and the vertical coordinate is vibration displacement).

[0036] In this embodiment, the vibration directions of the determined complementary motor groups are on the same straight line, so when the vibration directions of the two complementary motors are opposite or away from each other, the vibration of the two motors can cancel each other out. The preset amplitude can be one value in the range of 0.2mm to 0.5mm, and the user can determine it according to the vibration tolerance of the device, which is not limited here.

[0037] In this application, for non-complementary motors, compensation current is directly injected to reduce vibration; for complementary motors, the first total power consumed by each complementary motor when performing current compensation alone can be estimated, and the second total power consumed when performing collaborative current compensation considering the vibration consumption of the complementary motor can be estimated. By comparing the sizes of the first total power and the second total power, the compensation current is injected to the complementary motor in a way that the corresponding total power is smaller, so as to collaboratively adjust the vibration of the complementary motor. In this application, the complementary motors in the multi-motor device can be identified, and the total power consumption of the complementary motors when performing collaborative current compensation and individual current compensation is compared, so as to inject compensation current to the complementary motor in a way that the power consumption is smaller, avoiding excessive power consumption and saving energy.

[0038] As a preferred embodiment, the vibration direction in the space of each motor is determined according to the position of each motor, and the complementary motor group is determined according to the vibration direction, which comprises:

[0039] S21: acquiring the monitoring video of the motor by the visual device;

[0040] S22: for each motor, identifying the spatial pose of the motor in the monitoring video;

[0041] S23: determining the spatial vibration direction of the motor according to the spatial pose of the motor;

[0042] S24: selecting two motors, connecting the corresponding spatial poses of the two motors to obtain a corresponding connection line;

[0043] S25: identifying whether the spatial vibration directions of the two motors are both on the connection line, if yes, the two motors form a complementary motor group, and the two motors are complementary motors in the complementary motor group, if not, the two motors are not complementary motors;

[0044] S26: for non-complementary motors, repeating steps S24 to S25 until all complementary motor groups are determined.

[0045] In this embodiment, since the vibration of the motor is mainly caused by the structural characteristics of the motor itself (such as the number, interval and size of the stator teeth), the motor stably reciprocates along the same line (such as along the axis of the motor), this line can be determined by pre-observation (manual observation or visual instrument observation), and a vector corresponding to the line can be generated by randomly selecting a direction from the two ends of the line. A three-dimensional coordinate system of the motor can be established with the center of the motor as the origin, and then the vector coordinates of the vector in the coordinate system are determined and stored in the computer device. In this embodiment, after the spatial pose of the motor is determined, a corresponding three-dimensional coordinate system is generated on the motor (the coordinate system changes accordingly as the pose of the motor changes), and a vector corresponding to the vector coordinates is marked at the center of the motor. The direction of the vector in space can be determined as the spatial vibration direction. In this embodiment, when the spatial vibration directions of the two motors are both on the connection line of the two motors, it means that when the two motors vibrate towards each other or away from each other, the vibration generated by the two motors can be reduced.

[0046] As a preferred embodiment, the compensation current is injected into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, which comprises:

[0047] S31: obtaining the historical current curve and the historical vibration curve of the independent motor, wherein the horizontal coordinate of the historical current curve is time, and the vertical coordinate is current, the horizontal coordinate of the historical vibration curve is time, and the vertical coordinate is vibration displacement;

[0048] S32: Align the time of the historical current curve with the time of the historical vibration curve;

[0049] S33: Identify all periodic critical points on the historical vibration curve to determine a plurality of sections constituting the historical vibration curve, and select a section with an amplitude less than a set amplitude on the historical vibration curve as a target vibration section;

[0050] S34: Determine the current sub-section corresponding to the target vibration section on the historical current curve;

[0051] S35: Retrieve the current current curve of the monitored independent motor, inject a compensation current into the independent motor, and change the fluctuation of the current curve of the independent motor to the fluctuation of the current sub-section.

[0052] As Figure 3 shown, injecting a compensation current into the independent motor changes the fluctuation of the current curve of the independent motor to the fluctuation of the current sub-section, including:

[0053] S351: Identify the fluctuation period of the current curve of the independent motor;

[0054] S352: Determine the subsequent predicted curve of the current curve according to the fluctuation period;

[0055] S353: Generate a subsequent target curve connected by a plurality of current sub-sections after the current curve;

[0056] S354: Determine the current and time corresponding to each curve point on the subsequent predicted curve, and determine the target current of the corresponding point on the subsequent target curve;

[0057] S355: Calculate the instantaneous compensation current at the time by the following formula:

[0058]

[0059] wherein, is the instantaneous compensation current, is the target current, is the current at the time;

[0060] When reaching any time, inject the instantaneous compensation current corresponding to the time into the independent motor.

[0061] Determine the total amount of electricity injected into each complementary motor under the condition of injecting a compensation current into each complementary motor, and determine the total amount of electricity as the first total amount of electricity, including:

[0062] S41: taking each complementary motor as an independent motor, performing steps S31-S34, and then performing steps S351-S355 to obtain the instantaneous compensation current at each subsequent moment;

[0063] S42: calculating the injected power corresponding to the instantaneous compensation current at each moment according to the following formula:

[0064]

[0065] wherein, is the injected power, is the interval duration between each two adjacent moments;

[0066] S43: accumulating the injected power corresponding to each moment to obtain the total power of the complementary motor;

[0067] S44: adding the total powers corresponding to the two complementary motors to obtain the first total power.

[0068] In this embodiment, the current and the vibration displacement are collected simultaneously, so the vibration curve is generated at the same time as the current curve. The current curve is the curve formed by the current collected from the last start to the current moment. The vibration curve is the curve formed by the vibration displacement collected from the last start to the current moment. The historical current curve is the current curve collected before the last start. The current curve generated in each motor start operation process in the past can be placed in the same coordinate system (the interval period between each operation is disconnected). Similarly, the historical vibration curve is the vibration curve collected before the last start. The vibration curve generated in each motor start operation process can also be placed in the same coordinate system, so as to correspond to the current curve.

[0069] In this embodiment, the vibration curve presents periodicity (even if the torque is suppressed, it presents a periodicity before suppression and another periodicity after suppression). The periodic critical point is the dividing point between two adjacent periods. If the period changes after torque suppression, the point where the change begins is also determined as a periodic critical point.

[0070] In the embodiment, the subsequent prediction curve, i.e. the curve generated from the end point of the current current curve and extending according to the period of the curve before the end point, if the current current curve develops according to the subsequent prediction curve, the vibration of the motor will still maintain the current vibration amplitude; the subsequent target curve, i.e. the current curve form to which the current current curve needs to be adjusted, each current sub-section is a current period corresponding to a vibration period, the subsequent target curve is connected by a plurality of (such as 20, which can be determined according to the remaining running time of the motor) current sub-sections, so if the current current curve develops according to the subsequent target curve, the motor can periodically vibrate at the vibration amplitude corresponding to the current sub-section, thereby achieving the effect of reducing vibration; in addition, a plurality of sections with an amplitude less than a set amplitude can be identified on the historical vibration curve, and the section with the smallest amplitude is selected as the target vibration section.

[0071] In the embodiment, the interval time between two adjacent time points can be 1 second or other time length, which is not limited here; each point on the generated subsequent target curve corresponds to a future time point, and at each future time point, the instantaneous compensation current corresponding to the time point is injected into the independent motor, and the injection time is the interval time between adjacent time points.

[0072] In the embodiment, if the first total electric quantity is greater than the second total electric quantity, for each complementary motor, the instantaneous compensation current corresponding to each future time point (determined according to step S41) is injected into the motor.

[0073] As a preferred embodiment, determining the total electric quantity injected in the case of injecting compensation current into the two complementary motors simultaneously includes:

[0074] S51: obtaining the historical current curve and the historical vibration curve of the two complementary motors;

[0075] S52: comparing the two obtained historical vibration curves to determine the complementary vibration section in the two historical vibration curves;

[0076] S53: for each complementary motor, identifying the fluctuation period of the current current curve of the complementary motor;

[0077] S54: determining the subsequent current fluctuation curve according to the fluctuation period;

[0078] S55: determining the current sub-section corresponding to the complementary vibration section of the complementary motor on the historical current curve of the complementary motor;

[0079] S56: generating a subsequent target curve connected by a plurality of current sub-sections after the current current curve;

[0080] S57: determine the current corresponding to each curve point on the subsequent current fluctuation curve and the time, determine the target current corresponding to the point on the subsequent target curve at the time, thereby determine the instantaneous compensation current at the time, and calculate the injected power corresponding to the instantaneous compensation current;

[0081] S58: accumulate the injected power corresponding to each time to obtain the total power of the complementary motor;

[0082] S59: add the total power corresponding to the two complementary motors to obtain the second total power.

[0083] Compare the two obtained historical vibration curves to determine the complementary vibration section in the two historical vibration curves, comprising:

[0084] S521: identify all periodic critical points in each historical vibration curve to determine a plurality of sections constituting the historical vibration curve;

[0085] S522: determine a section of one of the historical vibration curves as a first section, and determine a section of the other historical vibration curve as a second section;

[0086] S523: select a first section as a base section;

[0087] S524: identify the period length corresponding to the base section, and then select a second section with the same period length as the base section as a comparison section;

[0088] S525: align each comparison section with the base section to determine a combined curve section of the comparison section and the base section, and calculate the fluctuation score of the combined curve section;

[0089] S526: repeat steps S523 to S525 until all fluctuation scores corresponding to each first section are obtained;

[0090] S527: determine the first section and the second section corresponding to the smallest fluctuation score as the complementary vibration section.

[0091] Align each comparison section with the base section to determine a combined curve section of the comparison section and the base section, and calculate the fluctuation score of the combined curve section, comprising:

[0092] Place the comparison section in the coordinate system of the base section, and align the comparison section with the base section at the beginning and end;

[0093] Identify all curve points on the base section as base curve points, and identify all curve points on the comparison section as comparison curve points;

[0094] Determine whether the positive direction of vibration of the complementary motor corresponding to the comparison section is the same as the positive direction of vibration of the complementary motor corresponding to the base section;

[0095] If the same, the vertical coordinate value of the corresponding combined curve point is obtained by adding the vertical coordinate value of each base curve point to the vertical coordinate value of the corresponding comparison curve point; if not the same, the vertical coordinate value of the corresponding combined curve point is obtained by subtracting the vertical coordinate value of the corresponding comparison curve point from the vertical coordinate value of each base curve point, wherein the horizontal coordinate value of the combined curve point is consistent with the horizontal coordinate values of the base curve point and the comparison curve point;

[0096] The smooth curve is used to connect each combined curve point, so as to obtain the combined curve segment;

[0097] It is identified whether the vibration amplitude of the combined curve segment is less than the preset amplitude, if not, the combined curve segment is excluded;

[0098] If yes, the fluctuation score of the combined curve segment is calculated through the following formula:

[0099]

[0100] Wherein, is the fluctuation score, is the vertical coordinate value of the i-th combined curve point on the combined curve segment, and n is the number of combined curve points on the combined curve segment.

[0101] In the embodiment, the method steps of determining the target current, the instantaneous compensation current and the injected electric quantity are consistent with the method steps corresponding to the independent motor, which will not be repeated here;

[0102] In the embodiment, the combined curve segment is the curve segment corresponding to the combined vibration of the two motors, if the vibration amplitude of the combined curve segment is smaller than that of any one motor, the vibrations of the two motors are mutually reduced; if the two vibration segments are complementary vibration segments, the vibration of the motor corresponding to the two vibration segments is mutually reduced to the greatest extent, that is, the amplitude of the combined curve segment is the smallest;

[0103] In the embodiment, the positive direction of the vibration of each motor can be determined according to the installation direction of the vibration sensor (the installation direction is determined by manual and stored in the computer device in advance), since the complementary motors reciprocate vibration on the same straight line, the positive directions of the vibrations of the two complementary motors are either the same or opposite; in the embodiment, in the case that the positive directions of the vibrations are the same, the vertical coordinate value of the corresponding combined curve point is obtained by adding the vertical coordinate value of each base curve point to the vertical coordinate value of the corresponding comparison curve point, and in the case that the positive directions of the vibrations are not the same, the vertical coordinate value of the corresponding combined curve point is obtained by subtracting the vertical coordinate value of the corresponding comparison curve point from the vertical coordinate value of each base curve point, which can ensure the accuracy of the vertical coordinate value of the combined curve point;

[0104] In the embodiment, the comparison section is placed in the coordinate system of the base section, and the comparison section is aligned with the base section, i.e. the horizontal coordinate of the starting point of the comparison section is the same as the horizontal coordinate of the starting point of the base section, and the terminal points of the two sections are naturally aligned; in addition, after the comparison section is moved to the coordinate system of the base section, the vertical coordinates of the points on the comparison section are aligned with the corresponding scales of the vertical coordinate of the coordinate system.

[0105] In the embodiment, if the first total electric quantity is not greater than the second total electric quantity, for each complementary motor, the corresponding instantaneous compensation current at each future time (the instantaneous compensation current determined according to steps S51-S57) is injected into the motor at the time.

[0106] As shown in FIG. 1, Figure 4 In one embodiment, a torque ripple suppression device is provided, which comprises:

[0107] a monitoring module configured to monitor the motor vibration and the corresponding current fluctuation of each motor in the multi-motor device;

[0108] a first processing module configured to determine the vibration direction of each motor in the space according to the position of the motor, determine the complementary motor group according to the vibration direction, and determine the motor not in the complementary motor group as an independent motor;

[0109] a second processing module configured to, for each independent motor, inject a compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so that the motor vibration is reduced to below a preset amplitude;

[0110] a third processing module configured to, for each pair of complementary motors in the complementary motor group, determine the total electric quantity injected in the case of injecting a compensation current into each complementary motor alone, and determine the total electric quantity as a first total electric quantity, wherein the vibration of each complementary motor is reduced to below a preset amplitude by injecting a compensation current into the complementary motor alone;

[0111] a fourth processing module configured to determine the total electric quantity injected in the case of injecting a compensation current into the two complementary motors cooperatively as a second total electric quantity, wherein the motor vibration generated by each of the two complementary motors is reduced by the other motor after the compensation current is injected into the two complementary motors cooperatively, so that the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0112] a fifth processing module configured to determine whether the first total electric quantity is greater than the second total electric quantity, and if not, inject a compensation current into each complementary motor alone, and if so, inject a compensation current into the two complementary motors cooperatively.

[0113] Figure 5 FIG. 1 shows the internal structure of a computer device in one embodiment. As shown in FIG. 1, Figure 5As shown, the computer device includes a processor, a memory, a network interface, an input device and a display screen connected via a system bus. The memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the computer device stores an operating system and may also store a computer program. When the computer program is executed by the processor, the processor may implement the torque pulsation suppression method provided in the embodiment of the present invention. The internal memory may also store a computer program. When the computer program is executed by the processor, the processor may implement the torque pulsation suppression method provided in the embodiment of the present invention. The display screen of the computer device may be a liquid crystal display or an electronic ink display screen. The input device of the computer device may be a touch layer covering the display screen, or a button, trackball or touchpad provided on the computer device housing, or an external keyboard, touchpad or mouse.

[0114] Those skilled in the art will understand that Figure 5 The structure shown in the figure is merely a block diagram of a portion of the structure related to the solution of the present invention and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0115] In one embodiment, the torque pulsation suppression device provided by the embodiment of the present invention can be implemented in the form of a computer program. The computer program can be used in Figure 5 The computer device shown in FIG. 1 is run on the computer device shown in FIG. The memory of the computer device can store various program modules constituting the torque pulsation suppression device, such as: Figure 4 The monitoring module, the first processing module, the second processing module, the third processing module, the fourth processing module and the fifth processing module shown in the figure are computer programs composed of various program modules, which enable the processor to execute the steps of the torque pulsation suppression method of various embodiments of the present invention described in this specification.

[0116] For example, Figure 5 The computer device shown can be Figure 4 The monitoring module in the torque pulsation suppression device shown executes step S1; the computer device can execute step S2 through the first processing module; the computer device can execute step S3 through the second processing module; the computer device can execute step S4 through the third processing module; the computer device can execute step S5 through the fourth processing module; and the computer device can execute step S6 through the fifth processing module.

[0117] In one embodiment, a computer device is provided, comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein when the processor executes the computer program, the following steps are performed:

[0118] S1: monitoring motor vibration and corresponding current fluctuation of each motor in the multi-motor device;

[0119] S2: determining vibration direction of each motor in the space according to the position of each motor, determining complementary motor groups according to the vibration direction, and determining motors not in the complementary motor groups as independent motors;

[0120] S3: for each independent motor, injecting compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so that the motor vibration is reduced to below a preset amplitude;

[0121] S4: for each pair of complementary motors in each complementary motor group, determining the total amount of electricity injected in the case of injecting compensation current into each complementary motor separately, and determining the total amount of electricity as a first total amount of electricity, wherein injecting compensation current into each complementary motor separately reduces the vibration of the complementary motor to below a preset amplitude;

[0122] S5: determining the total amount of electricity injected in the case of injecting compensation current into the two complementary motors cooperatively, wherein after injecting compensation current into the two complementary motors cooperatively, the motor vibrations generated by each of the two complementary motors cancel each other out, so that the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0123] S6: determining whether the first total amount of electricity is greater than the second total amount of electricity, if not, injecting compensation current into each complementary motor separately, and if yes, injecting compensation current into the two complementary motors cooperatively.

[0124] In one embodiment, a computer readable storage medium is provided, and the computer readable storage medium stores a computer program. When the computer program is executed by a processor, the processor executes the following steps:

[0125] S1: monitoring motor vibration and corresponding current fluctuation of each motor in the multi-motor device;

[0126] S2: determining vibration direction of each motor in the space according to the position of each motor, determining complementary motor groups according to the vibration direction, and determining motors not in the complementary motor groups as independent motors;

[0127] S3: for each independent motor, injecting compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so that the motor vibration is reduced to below a preset amplitude;

[0128] S4: determining, for each of the two complementary motors in each complementary motor group, a total amount of injected electricity in the case of separately injecting compensation current into each complementary motor, and determining the total amount of injected electricity as a first total amount of injected electricity, wherein the vibration of each complementary motor is reduced to below a preset amplitude by separately injecting compensation current into each complementary motor;

[0129] S5: determining that the total amount of injected electricity in the case of jointly injecting compensation current into the two complementary motors is a second total amount of injected electricity, wherein the motor vibration generated by each of the two complementary motors is mutually reduced after compensation current is jointly injected into the two complementary motors, so that the combined vibration of the two complementary motors is reduced to below a preset amplitude;

[0130] S6: determining whether the first total amount of injected electricity is greater than the second total amount of injected electricity, and if not, separately injecting compensation current into each complementary motor, and if so, jointly injecting compensation current into the two complementary motors.

[0131] It should be understood that although each step in the flowchart of each embodiment of the present application is displayed in sequence according to the direction of the arrow, these steps are not necessarily executed in sequence according to the direction of the arrow. Unless otherwise specified herein, the execution of these steps is not strictly limited in sequence, and these steps can be executed in other sequences. Moreover, at least a part of the steps in each embodiment can include multiple sub-steps or multiple stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of these sub-steps or stages is not necessarily sequential, but can be executed in rotation or alternation with at least a part of other steps or sub-steps or stages of other steps.

[0132] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program. The program can be stored in a non-volatile computer readable storage medium, and when the program is executed, the processes of the above-mentioned embodiment methods can be included. Any reference to memory, storage, database or other medium used in each embodiment of the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), Synchlink DRAM (SLDRAM), Rambus direct RAM (RDRAM), direct RAM bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0133] Any combination of the technical features of the above-mentioned embodiments can be combined. In order to make the description simple, all possible combinations of each technical feature in the above-mentioned embodiments are not described, however, as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0134] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application.

Claims

1. A method for suppressing torque pulsation, characterized in that: The method comprises: S1: Monitor the motor vibration and corresponding current fluctuation of each motor in a multi-motor device; S2: determining the vibration direction of each motor in space based on the position of each motor, determining a complementary motor group based on the vibration direction, and determining the motor that is not in the complementary motor group as an independent motor; S3: For each independent motor, injecting a compensation current into the independent motor according to the current fluctuation corresponding to the motor vibration of the independent motor, so as to reduce the motor vibration to below a preset amplitude; S4: for the two complementary motors in each complementary motor group, determining a total amount of electricity injected when a compensation current is injected into each complementary motor individually, and determining the total amount of electricity as a first total amount of electricity, wherein the compensation current is injected into each complementary motor individually so that a vibration of the complementary motor is reduced to below a preset amplitude; S5: determining a total amount of electricity injected when the compensation current is cooperatively injected into the two complementary motors as a second total amount of electricity, wherein after the compensation current is cooperatively injected into the two complementary motors, motor vibrations generated by the two complementary motors cancel each other out, so that the combined vibration of the two complementary motors is reduced to below a preset amplitude; S6: Determine whether the first total electrical quantity is greater than the second total electrical quantity. If not, inject a compensation current into each complementary motor individually. If so, inject a compensation current into the two complementary motors in a coordinated manner.

2. The method according to claim 1, characterized in that The vibration direction of each motor in space is determined based on the position of each motor, and the complementary motor group is determined based on the vibration direction, including: S21: collecting monitoring video of the motor through a visual device; S22: For each motor, identify the spatial posture of the motor in the monitoring video; S23: determining the spatial vibration direction of the motor according to the spatial posture of the motor; S24: Select two motors, connect the corresponding spatial postures of the two motors, and obtain corresponding connecting lines; S25: Identify whether the spatial vibration directions of the two motors are both on the connection line. If so, the two motors form a complementary motor group, and the two motors are complementary motors in the complementary motor group. If not, the two motors are not complementary motors. S26: For non-complementary motors, repeat steps S24 to S25 until all complementary motor groups are determined.

3. The method according to claim 2, characterized in that Injecting a compensation current into the independent motor according to current fluctuations corresponding to motor vibration of the independent motor includes: S31: Obtain a historical current curve and a historical vibration curve of the independent motor, wherein the abscissa of the historical current curve is time and the ordinate is current; the abscissa of the historical vibration curve is time and the ordinate is vibration displacement; S32: Align the time of the historical current curve with the historical vibration curve; S33: identifying all periodic critical points on the historical vibration curve to determine a number of segments constituting the historical vibration curve, thereby selecting a segment on the historical vibration curve having an amplitude smaller than a set amplitude as a target vibration segment; S34: determining a current sub-segment corresponding to the target vibration segment on the historical current curve; S35: Retrieve the monitored current curve of the independent motor, inject a compensation current into the independent motor, and change the fluctuation of the current curve of the independent motor into the fluctuation of the current sub-segment.

4. The method according to claim 3, characterized in that Injecting a compensation current into the independent motor to change the fluctuation of the current curve of the independent motor into the fluctuation of the current sub-segment includes: S351: Identify the fluctuation period of the current curve of the independent motor; S352: Determine a subsequent prediction curve of the current curve based on the fluctuation period; S353: generating a subsequent target curve formed by connecting a plurality of current sub-segments after the current current curve; S354: Determine the current and time corresponding to each curve point on the subsequent prediction curve, and determine the target current of the point corresponding to the subsequent target curve at that time; S355: Calculate the instantaneous compensation current at this moment using the following formula: in, is the instantaneous compensation current, is the target current, is the current at that moment; When any moment arrives, the instantaneous compensation current corresponding to the moment is injected into the independent motor.

5. The method according to claim 4, characterized in that Determining a total amount of electricity injected when the compensation current is injected into each complementary motor individually, and determining the total amount of electricity as the first total amount of electricity includes: S41: Treat each complementary motor as an independent motor, execute steps S31 to S34, and then execute steps S351 to S355 to obtain the instantaneous compensation current at each subsequent moment; S42: Calculate the injected power corresponding to the instantaneous compensation current at each moment according to the following formula: in, To inject electricity, is the interval between every two adjacent moments; S43: Accumulate the injected power corresponding to each moment to obtain the total power of the complementary motor; S44: Add the total electrical quantities corresponding to the two complementary motors to obtain a first total electrical quantity.

6. The method according to claim 2, characterized in that Determining the total amount of electricity injected when the compensation current is cooperatively injected into the two complementary motors as the second total amount of electricity includes: S51: Obtain historical current curves and historical vibration curves of two complementary motors; S52: comparing the two acquired historical vibration curves to determine complementary vibration segments in the two historical vibration curves; S53: For each complementary motor, identifying a fluctuation period of a current curve of the complementary motor; S54: determining a subsequent current fluctuation curve based on the fluctuation period; S55: determining a current sub-section corresponding to the complementary vibration section of the complementary motor on a historical current curve of the complementary motor; S56: generating a subsequent target curve formed by connecting a plurality of current sub-segments after the current current curve; S57: Determine the current and time corresponding to each curve point on the subsequent current fluctuation curve, determine the target current of the point corresponding to the subsequent target curve at that time, thereby determining the instantaneous compensation current at that time, and calculate the injected power corresponding to the instantaneous compensation current; S58: Accumulate the injected power corresponding to each moment to obtain the total power of the complementary motor; S59: Add the total electrical quantities corresponding to the two complementary motors to obtain a second total electrical quantity.

7. The method according to claim 6, characterized in that Comparing the two acquired historical vibration curves to determine complementary vibration sections in the two historical vibration curves includes: S521: Identify all period critical points in each historical vibration curve to determine a number of segments constituting the historical vibration curve; S522: determining a segment of one of the historical vibration curves as a first segment, and determining a segment of the other historical vibration curve as a second segment; S523: Select a first segment as a basic segment; S524: Identify the cycle duration corresponding to the basic segment, and then use a second segment having the same cycle duration as the basic segment as a comparison segment; S525: aligning each comparison segment with the base segment, thereby determining a combined curve segment of the comparison segment and the base segment, and calculating a fluctuation score of the combined curve segment; S526: Repeat steps S523 to S525 until all fluctuation scores corresponding to each first segment are obtained; S527: Determine the first segment and the second segment corresponding to the minimum fluctuation score as complementary vibration segments.

8. The method according to claim 7, characterized in that Each alignment segment is aligned with the base segment to determine a combined curve segment of the alignment segment and the base segment. Calculating the fluctuation score of the combined curve segment includes: Place the comparison segment in the coordinate system of the base segment and align the comparison segment with the base segment end to end; Identify all curve points on the basic section as basic curve points, and identify all curve points on the comparison section as comparison curve points; Determine whether the positive vibration direction of the complementary motor corresponding to the comparison section is the same as the positive vibration direction of the complementary motor corresponding to the basic section; If they are the same, the ordinate value of each base curve point is added to the ordinate value of the corresponding comparison curve point to obtain the ordinate value of the corresponding combined curve point; if they are different, the ordinate value of each base curve point is subtracted from the ordinate value of the corresponding comparison curve point to obtain the ordinate value of the corresponding combined curve point, where the abscissa value of the combined curve point is consistent with the abscissa values ​​of the base curve point and the comparison curve point; Connect the combined curve points with smooth curves to obtain combined curve segments; Identify whether the vibration amplitude of the combined curve segment is less than a preset amplitude, and if not, exclude the combined curve segment; If so, the fluctuation score of the combined curve segment is calculated using the following formula: in, is the volatility score, is the ordinate value of the i-th combined curve point on the combined curve segment, and n is the number of combined curve points on the combined curve segment.

9. A torque pulsation suppression device, characterized in that: The device comprises: A monitoring module for monitoring the motor vibration and corresponding current fluctuation of each motor in a multi-motor device; a first processing module, configured to determine a vibration direction of each motor in space based on the position of each motor, determine a complementary motor group based on the vibration direction, and determine a motor that is not in the complementary motor group as an independent motor; A second processing module is configured to inject a compensation current into each independent motor according to a current fluctuation corresponding to the motor vibration of the independent motor, so as to reduce the motor vibration to below a preset amplitude; a third processing module, configured to determine, for each of the two complementary motors in each complementary motor group, a total amount of electricity injected when a compensation current is injected into each complementary motor individually, and determine the total amount of electricity as a first total amount of electricity, wherein the compensation current is injected into each complementary motor individually so that a vibration of the complementary motor is reduced to below a preset amplitude; a fourth processing module, configured to determine a total amount of electricity injected when a compensation current is cooperatively injected into the two complementary motors as a second total amount of electricity, wherein, after the compensation current is cooperatively injected into the two complementary motors, motor vibrations generated by the two complementary motors cancel each other out, such that a combined vibration of the two complementary motors is reduced to below a preset amplitude; The fifth processing module is used to determine whether the first total power is greater than the second total power. If not, a compensation current is injected into each complementary motor separately. If so, a compensation current is injected into the two complementary motors in a coordinated manner.

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