Motor belt speed smooth switching method, system, device and equipment and storage medium

Abstract

The invention provides a motor belt speed smooth switching method, system, device and equipment and a storage medium, and relates to the technical field of motor control. The method is applied to a first asynchronous motor, and when a switching instruction is received, the method comprises the following steps: adjusting a first flux linkage amplitude of the first asynchronous motor to a preset second flux linkage amplitude according to a preset amplitude adjustment rate and a flux linkage instruction of the first asynchronous motor within a preset flux linkage adjustment duration; within a preset torque adjustment duration, according to the torque instruction of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque according to a preset torque adjustment rate; blocking the trigger signal in a first preset duration after the removal instruction is received; wherein the trigger signal is used for triggering a pulse of a frequency converter of the first asynchronous motor. According to the method provided by the invention, the problem of how to realize smooth switching of the belt speed of the motor in the working process of the multi-motor variable frequency driving system is solved.

Description

Technical Field

[0001] The present application relates to the field of motor control, and in particular to a method, system, device, equipment and storage medium for smooth switching of motor belt speed. Background Art

[0002] The load of the multi-motor variable frequency drive system varies under different working conditions. In order to achieve its low-energy operation goal, when the load is low, some motors need to be cut off; when the load is high, these motors need to be put back into operation to ensure that the multi-motor variable frequency drive system always maintains a high-efficiency operation state.

[0003] During the operation of the multi-motor variable frequency drive system, if the belt speed hard switching method is adopted, significant mechanical and electrical stress will be generated, which may cause damage to the electromechanical equipment; while if the stop switching method is adopted, the working efficiency will be reduced. Therefore, the problem that needs to be solved urgently is how to achieve smooth switching of the motor belt speed during the operation of the multi-motor variable frequency drive system. Summary of the invention

[0004] The present application provides a method, system, device, equipment and storage medium for smoothly switching the motor belt speed, so as to solve the problem of how to achieve smooth switching of the motor belt speed during the operation of a multi-motor variable frequency drive system.

[0005] A first aspect of the present application provides a motor belt speed smooth switching method, which is applied to a first asynchronous motor of a motor belt speed smooth switching system, wherein the first asynchronous motor refers to an asynchronous motor that receives a switching instruction among multiple asynchronous motors of the motor belt speed smooth switching system. When the switching instruction is received, the method includes:

[0006] Within a preset flux adjustment time, according to the flux command of the first asynchronous motor, adjusting the first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate;

[0007] Within a preset torque adjustment time, according to the torque command of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate;

[0008] When the first preset time is reached after the removal instruction is received, the trigger signal is blocked; wherein the first preset time is greater than the flux adjustment time and the torque adjustment time; the trigger signal is used to trigger the pulse of the frequency converter of the first asynchronous motor; the removal instruction is a switching instruction.

[0009] In a possible design, within a preset flux adjustment time, according to a flux instruction of the first asynchronous motor, adjusting a first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate includes:

[0010] The amplitude adjustment rate is obtained according to the flux adjustment time and the difference between the second flux amplitude and the first flux amplitude;

[0011] Within the flux adjustment time, according to the flux instruction, the first flux amplitude is adjusted to the second flux amplitude at the amplitude adjustment rate;

[0012] Within a preset torque adjustment time, according to the torque command of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate, including:

[0013] When the first asynchronous motor meets the preset conditions, the torque adjustment rate is obtained according to the torque adjustment time and the difference between the second torque and the first torque; wherein, when the removal instruction is received, the torque adjustment time is less than or equal to the flux adjustment time;

[0014] Within the torque adjustment time, according to the torque command, the first torque is adjusted to the second torque at the torque adjustment rate.

[0015] In a possible design, the first asynchronous motor is re-started at a second preset time after receiving the input instruction, and the torque adjustment time is less than or equal to the second preset time; wherein the input instruction is another switching instruction.

[0016] In a possible design, the preset conditions include: receiving a cut-off instruction, or receiving an input instruction, and the real-time flux amplitude is greater than half of the first flux amplitude.

[0017] In a possible design, the motor speed smooth switching system further includes a plurality of second asynchronous motors; each second asynchronous motor refers to an asynchronous motor that has not received a switching instruction among the plurality of asynchronous motors in the speed smooth switching system; the torque adjustment duration includes a plurality of adjustment cycles, and the target adjustment cycle is any one of the last preset number of adjustment cycles of the plurality of adjustment cycles;

[0018] When receiving the input instruction, for the target adjustment period, within the preset torque adjustment time, according to the torque instruction of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to the preset second torque at a preset torque adjustment rate, including:

[0019] Obtaining a third torque and an average torque of the plurality of second asynchronous motors; wherein the third torque is the torque of the torque command at the beginning of the target adjustment cycle;

[0020] When the third torque is greater than the average torque, a fourth torque is obtained according to the third torque and the average torque; wherein the fourth torque is the torque of the torque command at the end of the target adjustment cycle;

[0021] Within the target adjustment period, according to the torque command, the third torque is adjusted to the fourth torque at a torque adjustment rate.

[0022] In a possible design, a fourth torque is obtained according to the third torque and the average torque, including:

[0023] Obtaining an anti-over-compensation speed of the first asynchronous motor according to a difference between the third torque and the average torque and a preset compensation coefficient;

[0024] The fourth torque is obtained according to the anti-overrun compensation speed and the third torque.

[0025] A second aspect of the present application provides a motor belt speed smooth switching system, the system comprising:

[0026] A first asynchronous motor, and a frequency converter electrically connected to the first asynchronous motor;

[0027] The first asynchronous motor is used to implement any one of the motor speed smoothing switching methods of the first aspect when receiving a switching instruction; the frequency converter is used to issue a driving voltage.

[0028] A third aspect of the present application provides a motor belt speed smooth switching device, which is applied to a first asynchronous motor of a motor belt speed smooth switching system, wherein the first asynchronous motor refers to an asynchronous motor that receives a switching instruction among multiple asynchronous motors of the belt speed smooth switching system. When receiving the switching instruction, the device includes:

[0029] A flux linkage instruction change slope limiting module is used to adjust the first flux linkage amplitude of the first asynchronous motor to a preset second flux linkage amplitude at a preset amplitude adjustment rate according to the flux linkage instruction of the first asynchronous motor within a preset flux linkage adjustment time;

[0030] A torque command change slope limiting module is used to adjust the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate according to the torque command of the first asynchronous motor within a preset torque adjustment time;

[0031] The blocking delay module is used to block the trigger signal at the first preset time after receiving the removal instruction; wherein the first preset time is greater than the flux adjustment time and the torque adjustment time; the trigger signal is used to trigger the pulse of the frequency converter of the first asynchronous motor; the removal instruction is a switching instruction.

[0032] A fourth aspect of the present application provides an electronic device, comprising: a memory, and a memory communicatively connected to a processor;

[0033] Memory stores computer-executable instructions;

[0034] When the processor executes the computer-executable instructions stored in the memory, it is used to implement the motor belt speed smooth switching method of any one of the first aspects.

[0035] The fifth aspect of the present application provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the motor belt speed smoothing switching method of any one of the first aspects.

[0036] The sixth aspect of the present application provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the motor belt speed smoothing switching method of any one of the first aspects.

[0037] The present application provides a method, system, device, equipment and storage medium for smooth switching of motor belt speed, the method comprising: within a preset flux adjustment time, according to the flux instruction of the first asynchronous motor, adjusting the first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate; within a preset torque adjustment time, according to the torque instruction of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate; blocking the trigger signal at the first preset time after receiving the cutting instruction. The following technical effects are achieved: through the flux adjustment time and the torque adjustment time, the flux amplitude and torque of the asynchronous motor are slowly adjusted, so that the smooth switching of the motor belt speed without stopping is achieved; after receiving the input instruction, the flux amplitude of the asynchronous motor is slowly adjusted to avoid the problem of overcurrent of the excitation current caused by the instantaneous increase of the flux amplitude, thereby causing mechanical stress and electrical stress; after receiving the switching instruction, the trigger signal is blocked, so that the asynchronous motor has a certain time to smoothly reduce the torque output. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] In order to more clearly illustrate the technical solutions in the present application or the prior art, a brief introduction is given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0039] Figure 1 A schematic diagram of a scenario of a method for smoothly switching the motor belt speed provided in an embodiment of the present application;

[0040] Figure 2 Schematic diagram of the process of the motor belt speed smooth switching method provided in the embodiment of the present application Figure 1 ;

[0041] Figure 3 Schematic diagram of the process of the motor belt speed smooth switching method provided in the embodiment of the present application Figure 2 ;

[0042] Figure 4 A block diagram of the vector control of an asynchronous motor provided in an embodiment of the present application;

[0043] Figure 5 This is a speed-time simulation diagram without applying the motor belt speed smoothing switching method;

[0044] Figure 6 This is the torque-time simulation diagram without applying the motor speed smoothing switching method;

[0045] Figure 7 This is the current-time simulation diagram without applying the motor speed smoothing switching method;

[0046] Figure 8 It is the speed time simulation diagram of the motor belt speed smooth switching method;

[0047] Fig. 9 It is the torque time simulation diagram of the motor belt speed smooth switching method;

[0048] Fig.10 It is the current-time simulation diagram of the motor belt speed smooth switching method;

[0049] Fig.11 A schematic diagram of the structure of a motor belt speed smooth switching device provided in an embodiment of the present application;

[0050] Fig.12 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0051] Reference numerals:

[0052] 111-incoming transformer; 112-inverter; 113-asynchronous motor; 114-three-phase current sensor; 115-three-phase voltage sensor; 120-cutter head;

[0053] 210- flux command change slope limiting module; 220- torque command change slope limiting module; 230- blocking delay module;

[0054] 310 - processor; 320 - memory; 330 - communication component; 340 - bus. DETAILED DESCRIPTION

[0055] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementations described in the following exemplary embodiments do not represent all implementations consistent with the present application. Instead, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0056] In the present application, words such as "first" and "second" are used to distinguish between identical or similar items with substantially the same functions and effects. Those skilled in the art will understand that words such as "first" and "second" do not limit the quantity and execution order, and words such as "first" and "second" do not necessarily limit the difference. It should be noted that in the present application, words such as "exemplary" or "for example" are used to indicate examples, illustrations or explanations. Any embodiment or design described as "exemplary" or "for example" in the present application should not be interpreted as being more preferred or more advantageous than other embodiments or designs. Specifically, the use of words such as "exemplary" or "for example" is intended to present related concepts in a specific way. In the present application, "at least one" refers to one or more, and "more" refers to two or more.

[0057] It should be noted that the term "at..." in the present application may be the instant when a certain situation occurs, or may be a period of time after a certain situation occurs, and the present application does not specifically limit this. In addition, the motor belt speed smooth switching method provided in the present application is only used as an example, and the motor belt speed smooth switching method may also include more or less content.

[0058] In order to clearly describe the technical solution of this application, some terms and technologies involved in this application are briefly introduced below:

[0059] Multi-motor variable frequency drive system: refers to a motor drive system composed of multiple frequency converters and multiple asynchronous motors. The multi-motor variable frequency drive system can realize the coordinated operation of multiple asynchronous motors.

[0060] Belt speed hard switching: refers to the method of directly switching the asynchronous motor into or out of the multi-motor variable frequency drive system without using a smooth transition process.

[0061] Stop and switch: refers to the method of switching the asynchronous motor back on or off the multi-motor variable frequency drive system after the electrical equipment connected to the asynchronous motor power is shut down and stopped.

[0062] Flux linkage command: refers to the command to control the magnitude of the flux linkage of the asynchronous motor. The flux linkage amplitude is the magnetic flux linked by the conductive coil or current loop, and is an important parameter in the operation of the asynchronous motor.

[0063] Torque command: refers to the command to control the power output of the asynchronous motor. Torque is the moment of force generated when the asynchronous motor rotates, and is an important parameter in the operation of the asynchronous motor.

[0064] The technical solution of the present application is described in detail with specific embodiments below. The following specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The present application will be described below in conjunction with the accompanying drawings.

[0065] In order to clearly understand the technical solution of the present application, the solution of the prior art is first introduced in detail.

[0066] The load of the multi-motor variable frequency drive system is different under different working conditions. In order to respond to the call for energy conservation and emission reduction, realize the economic operation of the multi-motor variable frequency drive system, and achieve its low-energy operation goal, when the load is low, some motors need to be cut off; when the load is high, these motors need to be put back into operation to ensure that the multi-motor variable frequency drive system always maintains a high-efficiency operation state.

[0067] During the operation of the multi-motor variable frequency drive system, if the belt speed hard switching method is used for this motor switching operation, significant mechanical and electrical stress will be generated, which may cause damage to the electromechanical equipment; if the electrical equipment is shut down and stopped, the asynchronous motor is switched at zero speed and then the electrical equipment is restarted, the working efficiency will be reduced. Therefore, realizing the fast belt speed smooth switching of asynchronous motors in the multi-motor variable frequency drive system is of great significance to the economic operation of the multi-motor variable frequency drive system and improving the working efficiency of electrical equipment.

[0068] Therefore, in order to solve the problem of how to achieve smooth switching of the motor speed during the operation of the multi-motor variable frequency drive system, it was found in the research that the present application proposes the following technical solutions: first, limit the change rate of the flux command output by the flux outer loop, so that the flux command gradually increases or decreases at a specified rate; second, limit the change rate of the torque command output by the speed outer loop, so that the torque command gradually increases or decreases at a specified rate; third, when receiving the cutting command, delay for a period of time and then block the trigger pulse of the inverter, so that the asynchronous motor has enough time to smoothly reduce the torque output; finally, recalculate the torque command after proportional adjustment based on the difference between the torque of the asynchronous motor and the average torque of the remaining multiple asynchronous motors, so as to avoid the asynchronous motor being put into operation at the end of the belt speed re-start, resulting in torque overshoot.

[0069] Based on the above creative findings, the technical solution of the present application is proposed.

[0070] The following introduces the application scenarios of the motor belt speed smooth switching method provided in this application.

[0071] Figure 1 A schematic diagram of a scenario of a motor belt speed smooth switching method provided in an embodiment of the present application. It should be noted that: Figure 1 What is shown are merely examples of scenarios in which the present application can be applied, to help those skilled in the art understand the technical content of the present application, but it does not mean that the present application cannot be used in other devices, systems, environments or scenarios.

[0072] like Figure 1 As shown, the application scenario includes: a multi-motor variable frequency drive system and a cutter head 120 on a shield machine.

[0073] The multi-motor variable frequency drive system includes: an incoming line transformer 111, three frequency converters 112 electrically connected to the incoming line transformer 111, an asynchronous motor 113 electrically connected to each frequency converter 112, and a three-phase current sensor 114 and a three-phase voltage sensor 115 between the frequency converters 112 and the asynchronous motors 113 electrically connected.

[0074] The incoming transformer 111 is a power input device of the multi-motor variable frequency drive system, which is used to convert the high-voltage electric energy provided by the power grid into low-voltage electric energy suitable for the inverter 112. By converting the voltage, the incoming transformer 111 can ensure that the inverter 112 and the asynchronous motor 113 electrically connected thereto operate within a safe voltage range, while reducing the loss during the power transmission process.

[0075] The inverter 112 is the core control device of the multi-motor variable frequency drive system, and is used to adjust the flux amplitude and torque of the asynchronous motor 113 by changing the power supply frequency according to a preset control strategy. The inverter 112 has a precise speed regulation function, which can realize the smooth start, acceleration and deceleration of the asynchronous motor 113, and at the same time improve the operating efficiency and flexibility of the multi-motor variable frequency drive system.

[0076] The asynchronous motor 113 is a power output device of the multi-motor variable frequency drive system, which is used to convert the electrical energy from the inverter 112 into mechanical energy to drive the cutter head 120 connected to it. The asynchronous motor 113 has the advantages of simple structure, reliable operation and convenient maintenance, and is specifically used to perform the motor belt speed smooth switching method of the present application. Figure 1 In, ω m is the mechanical speed of the asynchronous motor 113, T en(n＝1,2,3) is the torque of the corresponding asynchronous motor 113.

[0077] In this application scenario, the parameters of the asynchronous motor 113 can be: rated voltage N n =690V, rated power P n =160kW, rated frequency f n =50Hz, pole pair number p=2, stator resistance R s=0.0302Ω, stator inductance L s =0.0112H, rotor resistance R r =0.017Ω, rotor inductance L r =0.0112H, excitation inductance L m =0.011H, transmission system moment of inertia J m =5kg·m 2 .

[0078] The three-phase current sensor 114 is used to monitor the current condition of the asynchronous motor 113 during operation. It can measure the current magnitude and direction in the motor winding in real time and feed this information back to the frequency converter 112 or the control system. By monitoring the current change, abnormal conditions such as overload and short circuit during operation of the asynchronous motor 113 can be discovered in time. Figure 1 in,i sn(n＝1,2,3) =[i sn,a ,i sn,b ,i sn,c ] is the three-phase current output by the corresponding inverter 112.

[0079] The three-phase voltage sensor 115 is used to monitor the voltage condition of the asynchronous motor 113 during operation. It can measure the voltage magnitude and phase at both ends of the motor winding in real time, and feed this information back to the frequency converter 112 or the control system. By monitoring the voltage change, the power supply condition of the asynchronous motor 113 can be understood, and voltage fluctuations or abnormalities can be discovered in time. Figure 1 In, v sn(n＝1,2,3) =[v sn,a , v sn,b , v sn,c ] is the three-phase voltage output by the corresponding inverter 112.

[0080] The shield machine is an important equipment for tunnel excavation. During the excavation process, the shield machine will pass through different geological rock layers, and the load of the cutter head 120 will also change accordingly. However, the number and capacity of the asynchronous motors 113 are generally designed according to the possible maximum working condition and a certain margin is left. Therefore, when the load of the cutter head 120 is low, some of the asynchronous motors 113 will be cut off, and when the load of the cutter head 120 is high, these asynchronous motors 113 will be put into use again.

[0081] In other application scenarios, the multi-motor variable frequency drive system is connected to power of other electrical equipment other than the cutter head 120 and installed on other equipment other than the shield machine.

[0082] The embodiments of the present application are introduced below in conjunction with the drawings in the specification.

[0083] Figure 2 Schematic diagram of the process of the motor belt speed smooth switching method provided in the embodiment of the present application Figure 1.like Figure 2 As shown, in the embodiment of the present application, the execution subject may be the first asynchronous motor of the motor belt speed smooth switching system, and the first asynchronous motor refers to an asynchronous motor that receives a switching instruction among multiple asynchronous motors in the belt speed smooth switching system; further, when multiple asynchronous motors receive the switching instruction, the first asynchronous motor is any one of the multiple asynchronous motors that need to be switched, and the first asynchronous motor may include an electronic device. When the first asynchronous motor receives the switching instruction, the motor belt speed smooth switching method provided in the embodiment of the present application includes the following steps.

[0084] S201. Within a preset flux adjustment time, according to a flux command of the first asynchronous motor, adjusting a first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate.

[0085] Specifically, the switching instruction is used to instruct the first asynchronous motor to switch on or off the multi-motor variable frequency drive system. The switching instruction is a switching instruction, and the switching instruction is another switching instruction. When the first asynchronous motor switches on or off the multi-motor variable frequency drive system, the instantaneously adjusted flux amplitude is limited to a slow adjustment, that is, within the flux adjustment time, the first flux amplitude is adjusted to the second flux amplitude at a preset amplitude adjustment rate. Among them, the flux adjustment time refers to the set time for adjusting the first flux amplitude to the second flux amplitude; the flux instruction refers to the target value or expected value set in the asynchronous motor control system to achieve precise control of the motor flux, and the second flux amplitude can be obtained according to the flux instruction; the first flux amplitude refers to the flux amplitude of the rotor side of the first asynchronous motor at the current moment; the second flux amplitude refers to the flux amplitude expected to be achieved by the rotor side of the first asynchronous motor after the flux adjustment time, and the second flux amplitude can be achieved at the end of the flux adjustment time or at a certain moment in the flux adjustment time.

[0086] The flux adjustment duration may include one adjustment period, and the first flux amplitude needs to be adjusted to the second flux amplitude within the adjustment period; the flux adjustment duration may also include multiple adjustment periods, and each adjustment period corresponds to its own starting flux amplitude and ending flux amplitude, the first flux amplitude is the starting flux amplitude of the first adjustment period, and the second flux amplitude is the ending flux amplitude of the last adjustment period, and the first flux amplitude needs to be gradually adjusted to the second flux amplitude within these adjustment periods. The adjustment curve of the flux amplitude indicates that the flux amplitude can be linearly related to the time variable, which can be simplified to a linear function, and the amplitude adjustment rate is a constant; the adjustment curve may also indicate that the flux amplitude is nonlinearly related to the time variable, which can be simplified to a quadratic function, or other curve functions, and the amplitude adjustment rate is a certain function. When the first asynchronous motor is put into the multi-motor variable frequency drive system, the second flux amplitude is greater than the first flux amplitude. When the first asynchronous motor is cut off from the multi-motor variable frequency drive system, the second flux amplitude is less than the first flux amplitude. The flux adjustment time during input and cut off can be the same or different.

[0087] S202. Within a preset torque adjustment time, according to a torque command of the first asynchronous motor, adjust the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate.

[0088] Specifically, when the first asynchronous motor is put into or removed from the multi-motor variable frequency drive system, the instantaneous adjusted torque is limited to slow adjustment, that is, the first torque is adjusted to the second torque within the torque adjustment time. The torque adjustment time refers to the set time for adjusting the first torque to the second torque; the torque command refers to the target value or expected value set in the asynchronous motor control system to achieve precise control of the motor torque, and the second torque can be obtained according to the torque command; the first torque refers to the torque of the first asynchronous motor at the current moment; the second torque refers to the torque expected to be achieved by the first asynchronous motor after the torque adjustment time, and the second torque can be achieved at the end of the torque adjustment time or at a certain moment in the torque adjustment time; the torque adjustment rate can be a constant or a function.

[0089] The adjustment of the torque is similar to the adjustment of the flux amplitude, and will not be described in detail in the embodiments of the present application.

[0090] S203, blocking the trigger signal for a first preset time after receiving the removal instruction; wherein the first preset time is greater than the flux adjustment time and the torque adjustment time.

[0091] Specifically, when the cut-off instruction is received, the trigger signal is blocked after a delay of the first preset time length, thereby blocking the trigger pulse of the frequency converter, so that the first asynchronous motor has a certain time to smoothly reduce the torque output; wherein, the first preset time length is greater than the flux adjustment time length, and the first preset time length is greater than the torque adjustment time length; the trigger signal is used to trigger the pulse of the frequency converter of the first asynchronous motor.

[0092] The embodiment of the present application provides a method for smooth switching of motor belt speed, the method comprising: within a preset flux adjustment time, according to the flux instruction of the first asynchronous motor, adjusting the first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate; within a preset torque adjustment time, according to the torque instruction of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate; blocking the trigger signal at the first preset time after receiving the switching instruction. The following technical effects are achieved: through the flux adjustment time and the torque adjustment time, the flux amplitude and torque of the asynchronous motor are slowly adjusted, so that the smooth switching of the motor belt speed without stopping is achieved; after receiving the input instruction, the flux amplitude of the asynchronous motor is slowly adjusted to avoid the problem of overcurrent of the excitation current caused by the instantaneous increase of the flux amplitude, thereby causing mechanical stress and electrical stress; at the first preset time after receiving the switching instruction, the trigger signal is blocked so that the asynchronous motor has a certain time to smoothly reduce the torque output.

[0093] Figure 3 Schematic diagram of the process of the motor belt speed smooth switching method provided in the embodiment of the present application Figure 2 ,like Figure 3 As shown, the motor belt speed smooth switching method provided in the embodiment of the present application is Figure 2 Based on the motor belt speed smooth switching method provided in the embodiment, the motor belt speed smooth switching method provided in the embodiment is further refined. The motor belt speed smooth switching method provided in the embodiment includes the following steps.

[0094] S301 : Obtain an amplitude adjustment rate according to a flux adjustment duration and a difference between a second flux amplitude and a first flux amplitude.

[0095] S302 . Within the flux adjustment time, according to the flux instruction, adjusting the first flux amplitude to the second flux amplitude at an amplitude adjustment rate.

[0096] Specifically, in the embodiment of the present application, the flux adjustment duration is selected to include n (n is greater than 1) adjustment cycles, and the adjustment curve of the flux amplitude indicates that there is a linear relationship between the flux amplitude and the time variable.

[0097] Figure 4 This is a block diagram of the asynchronous motor vector control provided by the embodiment of the present application. Figure 4As shown, a flux command change slope limiter (dashed box 1) is added to the outer loop of the flux. is the first flux amplitude, is the second flux amplitude, B L B is the switching instruction; L =1 is the input instruction, which is triggered by the rising edge; B L When =0, it is the removal instruction, which is triggered by the falling edge.

[0098] When receiving the input command, B L From 0 to 1, the flux command changes the slope limiter output The changing rule is:

[0099]

[0100] in, is the ending flux amplitude of the ith adjustment cycle among n adjustment cycles, exist hour, The ending flux amplitude is no longer adjusted after that; When the rate is adjusted according to the amplitude within the adjustment period Will Increase to Δt is the duration of the adjustment cycle, Also called the amplitude increase rate, it is the absolute value of the difference between the second flux amplitude and the first flux amplitude, and is related to the flux adjustment time. ratio. The value of can be within [0.1s, 1s], and in the embodiment of the present application, the value is 0.1s.

[0101] When receiving the removal command, B L From 1 to 0, the flux command change slope limiter output The changing rule is:

[0102]

[0103] Among them, hour, The ending flux amplitude is no longer adjusted after that; When the rate is adjusted according to the amplitude within the adjustment period Will Reduce to Also called the amplitude reduction rate, it is the absolute value of the difference between the second flux amplitude and the first flux amplitude, and is related to the flux adjustment time. ratio.

[0104] S303: When the first asynchronous motor meets a preset condition, a torque adjustment rate is obtained according to a torque adjustment duration and a difference between the second torque and the first torque.

[0105] S304. Within the torque adjustment time, according to the torque instruction, adjust the first torque to the second torque at the torque adjustment rate.

[0106] In a possible design, the preset conditions include: receiving a cut-off instruction, or receiving an input instruction, and the real-time flux amplitude is greater than half of the first flux amplitude.

[0107] Specifically, if Figure 4 As shown, the torque command change slope limiting module (dashed box 2) is used to limit the change rate of the second torque output by the speed outer loop. is the real-time flux amplitude, T eref0 is the first torque, T eref is the second torque, B L_MS According to B L This variable outputs the second preset duration t d2 Monostable output signal.

[0108] When receiving the input command, B L From 0 to 1, the torque command change slope limit module is based on and The numerical relationship between them, output T eref .

[0109] exist When the torque command change slope limit module outputs T eref =0;

[0110] exist When the torque command change slope limit module outputs T eref The changing rule is:

[0111]

[0112] Among them, T eref(i) is the end torque of the ith adjustment cycle among n adjustment cycles, T eref(n) =T eref In T eref(i-1) =T eref When T eref(i) The final torque after T is no longer adjusted; eref(i-1) <T eref When, within this adjustment period, the rate k is adjusted according to the torque TU , T eref(i-1) Increase to T eref(i) ;k TUAlso called the torque increase rate, it is the absolute value of the difference between the second torque and the first torque, and is related to the torque adjustment time t TU In the present embodiment, t TU The value is 2s.

[0113] When receiving the removal command, B L From 1 to 0, the torque command changes the slope limiter output T eref The changing rule is:

[0114]

[0115] Among them, in T eref(i-1) =0, T eref(i) The end flux amplitude is no longer adjusted after T eref(i-1) >0, within the adjustment period, the rate k is adjusted according to the torque TD , T eref(i-1) Reduced to T eref(i) ;k TD Also called the torque reduction rate, it is the absolute value of the difference between the second torque and the first torque, and is related to the torque adjustment time t TD In the present embodiment, t TD The value is 1s.

[0116] When the removal instruction is received, the torque adjustment time is less than or equal to the flux adjustment time. Therefore, in the embodiment of the present application, t TD The value is 1s.

[0117] In a possible design, the first asynchronous motor is re-started at a second preset time after receiving the input instruction, and the torque adjustment time is less than or equal to the second preset time; wherein the input instruction is another switching instruction.

[0118] Specifically, in the embodiment of the present application, the second preset time length t d2 The value is 5s.

[0119] S305: blocking the trigger signal at a first preset time after receiving the removal instruction.

[0120] Specifically, through the locking delay module (dashed box 3), in the first preset time length t d1 When , the trigger signal is blocked.

[0121] In a possible design, the motor speed smooth switching system further includes a plurality of second asynchronous motors; each second asynchronous motor refers to an asynchronous motor that has not received a switching instruction among the plurality of asynchronous motors in the speed smooth switching system; the torque adjustment duration includes a plurality of adjustment cycles, and the target adjustment cycle is any one of the last preset number of adjustment cycles of the plurality of adjustment cycles;

[0122] When receiving the input instruction, for the target adjustment period, S202 includes:

[0123] S401, obtaining a third torque and an average torque of a plurality of second asynchronous motors.

[0124] S402: Obtain an anti-over-compensation speed of the first asynchronous motor according to a difference between the third torque and the average torque and a preset compensation coefficient.

[0125] S403: Obtain a fourth torque according to the anti-overrun compensation speed and the third torque.

[0126] S404. Within the target adjustment period, according to the torque instruction, adjust the third torque to a fourth torque at a torque adjustment rate.

[0127] Specifically, the difference between the torque of the asynchronous motor and the average torque of the other multiple asynchronous motors is sent to the input side of the speed outer loop after proportional adjustment to avoid the asynchronous motor being put into use at the end of the belt speed re-throw, resulting in torque overshoot.

[0128] At the end of the input phase, that is, the last preset number of adjustment cycles of the multiple adjustment cycles of the input phase, in order to avoid the motor electromagnetic torque due to the speed outer loop PI ω The controller is saturated and overshoot occurs. A torque overshoot limiting module (dashed box 4) is added to the speed outer loop. The specific method is as follows: Get the third torque T e , and the average torque T of the second asynchronous motors avg , the third torque is the torque of the torque command at the beginning of the target adjustment cycle. e >T avg When, according to T e and T avg , and obtain the fourth torque, which is the torque of the torque command at the end of the target adjustment cycle.

[0129] According to the third torque and the average torque, the fourth torque is obtained, which refers to the period of the monostable trigger, that is, when B L_MS >0, T e With T avg Subtract, and multiply the difference by the compensation coefficient K avg Then get the anti-overspeed compensation speed ω avg , and limit ω avg If it is greater than zero, it will be subtracted from the speed command. avg The value of can be the droop coefficient K dp 50 to 100 times, and 100 times is taken in the embodiment of the present application.

[0130] The technical effects of the embodiments of the present application are as follows: the present application is applicable to both motor control systems with speed sensors and motor control systems without speed sensors, and is applicable to both magnetic field oriented control methods and direct torque control methods, and has strong applicability; the present application only contains simple arithmetic operations and logical judgments, and does not require the establishment of a complex motor model, and is simple, easy to implement and highly reliable.

[0131] Figure 5 This is a speed-time simulation diagram without applying the motor belt speed smoothing switching method; Figure 6 This is the torque-time simulation diagram without applying the motor speed smoothing switching method; Figure 7 This is the current-time simulation diagram without applying the motor speed smoothing switching method; Figure 8 It is the speed time simulation diagram of the motor belt speed smooth switching method; Fig. 9 It is the torque time simulation diagram of the motor belt speed smooth switching method; Fig.10 This is a current-time simulation diagram of the motor speed smoothing switching method. Figures 5 to 10 The partial physical simulation curve of the asynchronous motor is provided when the cut-off and put-in commands are respectively issued to the asynchronous motor No. 3 at t=6s and t=15s, wherein the speed command is reduced from 1500rpm to 1000rpm at t=10s.

[0132] like Figures 5 to 7 As shown in the figure, when the motor belt speed smooth switching method is not applied, the electromagnetic torque of motor No. 3 increases instantaneously after receiving the input command, and the motor current peak is close to 600A, reaching 2.4 times the stable working current; among them, Figure 6 The torque-time simulation diagrams of asynchronous motors No. 1 and No. 2 are also shown.

[0133] like Figures 8 to 10 As shown in the figure, when the motor belt speed smooth switching method is applied, the electromagnetic torque of motor No. 3 increases slowly after receiving the input command, and the current peak value during the rising process is 260A, which is only 1.08 times the current of the stable working condition; Fig. 9 The torque-time simulation diagrams of asynchronous motors No. 1 and No. 2 are also shown.

[0134] This simulation comparison result verifies that the motor speed smoothing switching method can effectively reduce the torque shock and current shock during the motor speed switching process.

[0135] The present application also provides a motor belt speed smooth switching system, such as Figure 1 As shown, the system includes:

[0136] A first asynchronous motor 113, and a frequency converter 112 electrically connected to the first asynchronous motor 113;

[0137] The first asynchronous motor 113 is used to implement the motor speed smoothing switching method in the above embodiment when receiving a switching instruction; the frequency converter 112 is used to generate a driving voltage.

[0138] The motor belt speed smooth switching system provided in the embodiment of the present application can perform Figures 2 to 10 The technical solution of the method embodiment shown in the figure has the same implementation principle and technical effect as Figures 2 to 10 The method embodiments shown are similar and will not be described in detail in the embodiments of the present application.

[0139] Fig.11 The schematic diagram of the structure of the motor belt speed smooth switching device provided in the embodiment of the present application is as follows: Fig.11 As shown, in the embodiment of the present application, the device is applied to the first asynchronous motor of the motor speed smooth switching system, and the motor speed smooth switching device can be located in the electronic device. When receiving the switching instruction, the motor speed smooth switching device includes:

[0140] The flux linkage instruction change slope limiting module 210 is used to adjust the first flux linkage amplitude of the first asynchronous motor to a preset second flux linkage amplitude at a preset amplitude adjustment rate according to the flux linkage instruction of the first asynchronous motor within a preset flux linkage adjustment time.

[0141] The torque command change slope limiting module 220 is used to adjust the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate according to the torque command of the first asynchronous motor within a preset torque adjustment time;

[0142] The blocking delay module 230 is used to block the trigger signal at the first preset time after receiving the removal instruction; wherein the first preset time is greater than the flux adjustment time and the torque adjustment time; the trigger signal is used to trigger the pulse of the inverter of the first asynchronous motor; the removal instruction is a switching instruction.

[0143] The motor belt speed smooth switching device provided in the embodiment of the present application can be performed Figure 2 The technical solution of the method embodiment shown in the figure has the same implementation principle and technical effect as Figure 2 The method embodiments shown are similar and will not be described in detail in the embodiments of the present application.

[0144] At the same time, the motor belt speed smoothing switching device provided in the embodiment of the present application is further refined on the basis of the motor belt speed smoothing switching device provided in the previous application embodiment.

[0145] The flux linkage instruction change slope limiting module 210 includes:

[0146] A first calculation module is used to obtain an amplitude adjustment rate according to a flux adjustment time and a difference between the second flux amplitude and the first flux amplitude;

[0147] The first adjustment module is used to adjust the first flux amplitude to the second flux amplitude according to the flux instruction and the amplitude adjustment rate within the flux adjustment time;

[0148] The torque command change slope limiting module 220 includes:

[0149] A second calculation module is used to obtain a torque adjustment rate according to the torque adjustment time and the difference between the second torque and the first torque when the first asynchronous motor meets the preset condition; wherein, when the removal instruction is received, the torque adjustment time is less than or equal to the flux adjustment time;

[0150] The second adjustment module is used to adjust the first torque to the second torque at a torque adjustment rate according to the torque instruction within the torque adjustment time.

[0151] In a possible design, the first asynchronous motor is re-started at a second preset time after receiving the input instruction, and the torque adjustment time is less than or equal to the second preset time; wherein the input instruction is another switching instruction.

[0152] In a possible design, the preset conditions include: receiving a cut-off instruction, or receiving an input instruction, and the real-time flux amplitude is greater than half of the first flux amplitude.

[0153] In a possible design, the motor speed smooth switching system further includes a plurality of second asynchronous motors; each second asynchronous motor refers to an asynchronous motor that has not received a switching instruction among the plurality of asynchronous motors in the speed smooth switching system; the torque adjustment duration includes a plurality of adjustment cycles, and the target adjustment cycle is any one of the last preset number of adjustment cycles of the plurality of adjustment cycles;

[0154] When receiving the input command, for the target adjustment period, the torque command change slope limiting module 220 includes:

[0155] A parameter acquisition module, used to acquire a third torque and an average torque of a plurality of second asynchronous motors; wherein the third torque is the torque of the torque command at the beginning of the target adjustment cycle;

[0156] A torque overshoot limiting module, used for obtaining a fourth torque according to the third torque and the average torque when the third torque is greater than the average torque; wherein the fourth torque is the torque of the torque command at the end of the target adjustment cycle;

[0157] The second adjustment module is used to adjust the third torque to a fourth torque at a torque adjustment rate according to the torque instruction within the target adjustment period.

[0158] In a possible design, the torque overshoot limiting module includes:

[0159] A third calculation module, used for obtaining an anti-over-compensation speed of the first asynchronous motor according to a difference between the third torque and the average torque and a preset compensation coefficient;

[0160] The fourth calculation module is used to obtain a fourth torque according to the anti-over-compensation speed and the third torque.

[0161] The motor belt speed smooth switching device provided in the embodiment of the present application can perform Figures 2 to 10 The technical solution of the method embodiment shown in the figure has the same implementation principle and technical effect as Figures 2 to 10 The method embodiments shown are similar and will not be described in detail in the embodiments of the present application.

[0162] The present application also provides an electronic device, Fig.12 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. Fig.12 As shown, the electronic device includes: the electronic device includes: at least one processor 310 and a memory 320. The electronic device also includes a communication component 330. The processor 310, the memory 320 and the communication component 330 are connected via a bus 340.

[0163] In the specific implementation process, at least one processor 310 executes the computer execution instructions stored in the memory 320, so that the at least one processor 310 is used to implement the motor belt speed smooth switching method of the above embodiment.

[0164] The specific implementation process of the processor 310 can be found in the above-mentioned method embodiment, and its implementation principle and technical effect are similar, so the embodiments of the present application will not be repeated here.

[0165] In the above embodiment, it should be understood that the processor 310 can be a central processing unit (CPU), or other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. The steps of the method disclosed in the application can be directly embodied as being executed by a hardware processor, or executed by a combination of hardware and software modules in the processor.

[0166] The memory 320 may include a high-speed RAM memory, and may also include a non-volatile storage NVM, such as at least one disk storage.

[0167] The bus 340 may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus 340 may be divided into an address bus, a data bus, a control bus, etc. For ease of representation, the bus 340 in the drawings of the present application is not limited to only one bus or one type of bus.

[0168] The above functions implemented by the electronic device and the main control device introduce the scheme provided by the embodiment of the present application. It is understandable that in order to implement the above functions, the electronic device or the main control device includes a hardware structure and / or software module corresponding to each function. In combination with the units and algorithm steps of each example described in the embodiment disclosed in the embodiment of the present application, the embodiment of the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered to exceed the scope of the technical solution of the embodiment of the present application.

[0169] The embodiment of the present application also provides a computer-readable storage medium, in which computer-executable instructions are stored, and when the computer-executable instructions are executed by a processor, they are used to implement the motor belt speed smooth switching method of the above embodiment. In the specific implementation of the above motor belt speed smooth switching method, each module can be implemented as a processor.

[0170] The above-mentioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic memory, flash memory, magnetic disk or optical disk. The readable storage medium can be any available medium that can be accessed by a general or special-purpose computer.

[0171] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be a component of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist as discrete components in an electronic device or a main control device.

[0172] The embodiment of the present application also provides a computer program product, including a computer program, which, when executed by a processor, is used to implement the motor belt speed smooth switching method of the above embodiment.

[0173] The computer program is stored in a readable storage medium. At least one processor can read the computer program from the readable storage medium. At least one processor executes the computer program to execute the solution provided in any of the above embodiments.

[0174] A person skilled in the art can understand that all or part of the steps of implementing the above-mentioned application embodiments can be completed by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, the steps of the above-mentioned method embodiment are executed; and the aforementioned storage medium includes: ROM, RAM, disk or optical disk, etc., various media that can store program codes.

[0175] So far, the technical solution of the present application has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present application is obviously not limited to these specific embodiments, and the above embodiments are only used to illustrate the technical solution of the present application rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for smoothly switching the motor belt speed, characterized in that: The method is applied to a first asynchronous motor of a motor belt speed smooth switching system, wherein the first asynchronous motor refers to an asynchronous motor that receives a switching instruction among multiple asynchronous motors of the belt speed smooth switching system. When the switching instruction is received, the method includes: Within a preset flux adjustment time, according to the flux command of the first asynchronous motor, adjusting the first flux amplitude of the first asynchronous motor to a preset second flux amplitude at a preset amplitude adjustment rate; Within a preset torque adjustment time, according to the torque command of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate; When the first preset time period has passed after the removal instruction is received, the trigger signal is blocked; wherein the first preset time period is greater than the flux adjustment time period and the torque adjustment time period; the trigger signal is used to trigger a pulse of the frequency converter of the first asynchronous motor; and the removal instruction is a switching instruction.

2. The method according to claim 1, characterized in that The step of adjusting the first flux amplitude of the first asynchronous motor to a preset second flux amplitude according to the flux instruction of the first asynchronous motor within a preset flux adjustment time and at a preset amplitude adjustment rate comprises: Obtaining the amplitude adjustment rate according to the flux adjustment time and the difference between the second flux amplitude and the first flux amplitude; Within the flux adjustment time, according to the flux instruction, adjusting the first flux amplitude to the second flux amplitude at the amplitude adjustment rate; The method of adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate according to the torque command of the first asynchronous motor within a preset torque adjustment time period includes: When the first asynchronous motor meets a preset condition, the torque adjustment rate is obtained according to the torque adjustment time and the difference between the second torque and the first torque; wherein, when the removal instruction is received, the torque adjustment time is less than or equal to the flux adjustment time; Within the torque adjustment time, according to the torque command, the first torque is adjusted to the second torque at the torque adjustment rate.

3. The method according to claim 2, characterized in that When the first asynchronous motor is re-started at a second preset time after receiving the input instruction, the torque adjustment time is less than or equal to the second preset time; wherein the input instruction is another switching instruction.

4. The method according to claim 2 or 3, characterized in that: The preset condition includes: receiving the removal instruction, or receiving the input instruction, and the real-time flux amplitude is greater than half of the first flux amplitude.

5. The method according to claim 1, characterized in that: The motor belt speed smooth switching system also includes a plurality of second asynchronous motors; each of the second asynchronous motors refers to an asynchronous motor that has not received the switching instruction among the plurality of asynchronous motors in the belt speed smooth switching system; the torque adjustment duration includes a plurality of adjustment cycles, and the target adjustment cycle is any one of the last preset number of adjustment cycles of the plurality of adjustment cycles; When receiving the input instruction, for the target adjustment period, within the preset torque adjustment time, according to the torque instruction of the first asynchronous motor, adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate, includes: Acquire a third torque and an average torque of the plurality of second asynchronous motors; wherein the third torque is the torque of the torque command at the beginning of the target adjustment cycle; When the third torque is greater than the average torque, a fourth torque is obtained according to the third torque and the average torque; wherein the fourth torque is the torque of the torque command at the end of the target adjustment period; Within the target adjustment period, according to the torque command, the third torque is adjusted to the fourth torque at the torque adjustment rate.

6. The method according to claim 5, characterized in that The step of obtaining a fourth torque according to the third torque and the average torque comprises: Obtaining an anti-over-compensation speed of the first asynchronous motor according to a difference between the third torque and the average torque and a preset compensation coefficient; The fourth torque is obtained according to the anti-overrun compensation speed and the third torque.

7. A motor belt speed smooth switching system, characterized in that: The system comprises: A first asynchronous motor, and a frequency converter electrically connected to the first asynchronous motor; The first asynchronous motor is used to implement the motor belt speed smoothing switching method as described in any one of claims 1 to 6 when receiving a switching instruction; the frequency converter is used to emit a driving voltage.

8. A motor belt speed smooth switching device, characterized in that: The device is applied to the first asynchronous motor of the motor belt speed smooth switching system, the first asynchronous motor refers to the asynchronous motor that receives the switching instruction among the multiple asynchronous motors of the belt speed smooth switching system, and when the switching instruction is received, the device includes: A flux linkage instruction change slope limiting module is used to adjust the first flux linkage amplitude of the first asynchronous motor to a preset second flux linkage amplitude at a preset amplitude adjustment rate within a preset flux linkage adjustment time according to the flux linkage instruction of the first asynchronous motor; a torque command change slope limiting module, used for adjusting the first torque of the first asynchronous motor to a preset second torque at a preset torque adjustment rate according to the torque command of the first asynchronous motor within a preset torque adjustment time; A blocking delay module is used to block the trigger signal at a first preset time after receiving a removal instruction; wherein the first preset time is greater than the flux adjustment time and the torque adjustment time; the trigger signal is used to trigger a pulse of the frequency converter of the first asynchronous motor; and the removal instruction is a switching instruction.

9. An electronic device, characterized in that: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executable instructions; When the processor executes the computer-executable instructions stored in the memory, it is used to implement the motor belt speed smooth switching method as described in any one of claims 1 to 6.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the motor belt speed smoothing switching method according to any one of claims 1 to 6.

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