Motor control method and control device, motor controller, and storage medium

Abstract

A motor control method and control device, a motor controller, and a storage medium, wherein the motor control method includes, in a process of controlling a motor to operate at constant power, a step (S1) of acquiring a feedback rotational speed of the motor, and, when it is determined that the feedback rotational speed is higher than a first rotational speed threshold, a step (S2) of acquiring a rotational speed loop control variable by a second rotational speed threshold higher than the first rotational speed threshold and the feedback rotational speed, and, when it is determined that the feedback rotational speed is higher than the second rotational speed threshold, a step (S3) of setting the second rotational speed threshold as a default variable of the rotational speed loop, setting the rotational speed loop control variable as an initial control variable of the rotational speed loop, and controlling the motor to operate at a constant rotational speed.

Description

[Technical field]

[0001] This disclosure claims priority to a Chinese patent application filed on March 7, 2022, bearing application number 202210217485.4 and entitled "Motor control method and control device, motor controller, and storage medium," the entire contents of which are incorporated herein by reference.

[0002] The present disclosure relates to the technical field of motor control, and in particular to a motor control method, a computer-readable storage medium, a motor controller, and a motor control device. [Background technology]

[0003] At present, high-speed and miniaturized brushless DC motors are being applied more and more widely, especially in the field of small power tools (such as handheld vacuum cleaners, etc.). When a small power tool is powered by a battery, the battery voltage will gradually decrease with the change of usage time, and in order to make the device output a constant power, it is necessary to introduce a constant power control policy during the process of the battery voltage decreasing.

[0004] In the related art, for a motor with constant power control, when the load becomes lighter due to the influence of the operating conditions, the rotation speed of the motor increases rapidly, and if the motor operates at a high rotation speed for a long time, it may damage the rotor system of the motor and also pose a threat to the safety of the user when using it. Summary of the Invention [Problem to be solved by the invention]

[0005] The present disclosure aims to solve at least to a certain extent one of the technical problems in the related art. Therefore, a first objective of the present disclosure is to provide a motor control method, which controls the motor to operate at a constant rotation speed when the rotation speed of the motor during constant power operation increases to a certain extent, effectively avoiding damage caused by the motor rotating at too high a speed, and realizing a smooth switch from constant power operation to constant rotation speed operation of the motor.

[0006] A second object of the present disclosure is to provide a computer-readable storage medium.

[0007] A third object of the present disclosure is to provide a motor controller.

[0008] A fourth object of the present disclosure is to provide a motor control device. [Means for solving the problem]

[0009] In order to achieve the above object, an embodiment of a first aspect of the present disclosure provides a motor control method including the steps of: acquiring a feedback rotational speed of a motor in a process of controlling the motor to operate at constant power; when it is determined that the feedback rotational speed is higher than a first rotational speed threshold, acquiring a rotational speed loop control variable by a second rotational speed threshold higher than the first rotational speed threshold and the feedback rotational speed; and when it is determined that the feedback rotational speed is higher than the second rotational speed threshold, setting the second rotational speed threshold as a default variable of the rotational speed loop, setting the rotational speed loop control variable as an initial control variable of the rotational speed loop, and controlling the motor to operate at a constant rotational speed.

[0010] According to the motor control method in the embodiment of the present disclosure, in the process of controlling the motor to operate at constant power, a feedback rotational speed of the motor is obtained, and when the feedback rotational speed is higher than a first rotational speed threshold, a rotational speed loop control variable is obtained based on the second rotational speed threshold and the feedback rotational speed, and when the feedback rotational speed is higher than the second rotational speed threshold, the second rotational speed threshold is set as a default variable of the rotational speed loop, the rotational speed loop control variable is set as an initial control variable of the rotational speed loop, and the motor is controlled to operate at a constant rotational speed, which not only effectively prevents damage caused by a motor rotational speed that is too high, but also realizes smooth switching from constant power operation to constant rotational speed operation of the motor.

[0011] According to one embodiment of the present disclosure, the step of obtaining a rotation speed loop control amount according to the second rotation speed threshold and the feedback rotation speed includes: obtaining a difference value between the second rotation speed threshold and the feedback rotation speed; performing rotation speed loop adjustment on the difference value to obtain an adjustment amount; and accumulating the adjustment amounts to obtain the rotation speed loop control amount.

[0012] According to an embodiment of the present disclosure, the motor control method further includes, in the process of controlling the motor to operate at a constant rotational speed, obtaining a time for constant rotational speed operation and a control variable of a power loop; and, when it is determined that the time is lower than a time threshold and the control variable of the rotational speed loop is higher than the control variable of the power loop, controlling the motor to operate at constant power.

[0013] According to one embodiment of the present disclosure, the motor control method further includes controlling the motor to run at a reduced speed or to stop when it is determined that the time is not below the time threshold.

[0014] According to an embodiment of the present disclosure, the time threshold is determined according to at least one of the following: temperature rise of the motor, heat dissipation condition, and rotor load capacity.

[0015] According to one embodiment of the present disclosure, the controlled variable of the power loop is the ratio between the target power and the DC bus voltage.

[0016] To achieve the above object, an embodiment of a second aspect of the present application provides a computer-readable storage medium storing a motor control program, the motor control program realizing the above motor control method when executed by a processor.

[0017] To achieve the above object, an embodiment of a third aspect of the present application provides a motor controller including a memory, a processor, and a motor control program stored in the memory and executable by the processor, the motor control program being stored in the memory and executable by the processor, and realizing the above motor control method when the processor executes the motor control program.

[0018] In order to achieve the above object, an embodiment of a fourth aspect of the present disclosure provides a motor control device including: an acquisition module used for acquiring a feedback rotational speed of a motor; and a control module used in a process of controlling the motor to operate at a constant power, when it is determined that the feedback rotational speed is higher than a first rotational speed threshold, to acquire a rotational speed loop control variable based on a second rotational speed threshold higher than the first rotational speed threshold and the feedback rotational speed, and when it is determined that the feedback rotational speed is higher than the second rotational speed threshold, to set the second rotational speed threshold as a default variable of the rotational speed loop and the rotational speed loop control variable as an initial control variable of the rotational speed loop, thereby controlling the motor to operate at a constant rotational speed. Effect of the Invention

[0019] According to the motor control device in the embodiment of the present disclosure, in the process of controlling the motor to operate at constant power, when the control module determines that the feedback rotational speed of the motor is higher than the first rotational speed threshold, it obtains a rotational speed loop control variable according to the second rotational speed threshold and the feedback rotational speed, and when it determines that the feedback rotational speed is higher than the second rotational speed threshold, it sets the second rotational speed threshold as a default variable of the rotational speed loop, and sets the rotational speed loop control variable as an initial control variable of the rotational speed loop, so as to control the motor to operate at constant rotational speed, thereby not only effectively preventing damage caused by the motor's rotational speed being too high, but also realizing a smooth switching from constant power operation to constant rotational speed operation of the motor.

[0020] Additional aspects and advantages of the disclosure will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the disclosure. [Brief description of the drawings]

[0021] [Figure 1] 1 is a schematic flow chart of a motor control method according to an embodiment of the present disclosure. [Diagram 2] FIG. 1 is a structural schematic diagram of a motor control system according to an embodiment of the present disclosure. [Diagram 3] 4 is a schematic flow chart of a motor control method according to another embodiment of the present disclosure. [Figure 4] 4 is a schematic flow chart of a motor control method according to another embodiment of the present disclosure. [Diagram 5] FIG. 2 is a block schematic diagram of a motor controller according to one embodiment of the present disclosure. [Figure 6] FIG. 1 is a block schematic diagram of a motor control device according to one embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] The following describes in detail the embodiments of the present disclosure, examples of which are shown in the drawings, in which the same or similar designations throughout indicate the same or similar elements, or elements having the same or similar functions. The embodiments described by referring to the following drawings are illustrative and are used only for the purpose of explaining the present disclosure, and should not be understood as limiting the present disclosure.

[0023] Hereinafter, a motor control method, a computer-readable storage medium, a motor controller, and a motor control device according to embodiments of the present disclosure will be described with reference to the drawings.

[0024] 1 is a schematic flow chart of a motor control method according to an embodiment of the present disclosure. Referring to FIG. 1, the motor control method may include the following steps:

[0025] Step S1: In the process of controlling the motor to operate at constant power, a feedback rotation speed of the motor is obtained.

[0026] It should be noted that constant power operation of a motor means that the output power of the motor does not fundamentally change during operation, i.e., the output power basically coincides with the target power, and the output torque of the motor decreases as the motor rotation speed increases.

[0027] In an embodiment of the present disclosure, in the process of controlling a motor to operate at constant power, as shown in FIG. 2, the power loop of the motor control system is connected to the current loop, at this time, the power loop generates a control amount based on a target power, and the control amount can be input to the current loop, and subsequent control is performed by the current loop to realize constant power operation of the motor.

[0028] In some embodiments, the controlled variable for the power loop is the ratio of the target power to the DC bus voltage.

[0029] For example, when a motor needs to be controlled to operate at constant power, a target power is obtained, which may be a power set by a user or may be a power automatically generated according to the control demand of the system, and is not specifically limited here. After the target power is obtained, it is input to the power loop, and at the same time, a voltage detection circuit detects the DC bus voltage, as shown in FIG. 2, the DC bus voltage is the voltage at the DC input terminal of the inverter, and the DC bus voltage is input to the power loop. Then, the power loop divides the target power by the DC bus voltage to obtain the ratio between the two, and the ratio is the control amount of the power loop, i.e., the predetermined current, and is input to the current loop, and the current loop realizes subsequent control according to the predetermined current, thereby realizing the constant power operation of the motor.

[0030] During the constant power operation of the motor, the feedback rotation speed of the motor is obtained in real time. Optionally, a position sensor can be provided inside the motor, and the feedback rotation speed of the motor can be detected by the position sensor; or a voltage detection circuit can be provided at the AC output end of the inverter shown in FIG. 2, and the voltage detection circuit can detect the zero crossing of the back electromotive force of the motor, and the feedback rotation speed of the motor can be estimated according to the zero crossing of the back electromotive force.

[0031] Step S2: when it is determined that the feedback rotation speed is higher than the first rotation speed threshold, obtain a rotation speed loop control variable according to a second rotation speed threshold and the feedback rotation speed, where the second rotation speed threshold is higher than the first rotation speed threshold.

[0032] In addition, the first rotation speed threshold and the second rotation speed threshold can be set according to specific performance parameters of the motor, and the second rotation speed threshold is also set as the target rotation speed when the motor is operating at a constant rotation speed.

[0033] For example, during the constant power operation of the motor, when the load on the motor becomes lighter due to the influence of the operating conditions, the feedback rotation speed of the motor increases and reaches a certain altitude, for example, higher than the first rotation speed threshold, then the motor continues to be controlled to operate at constant power and enters the speed loop buffer, that is, the second rotation speed threshold and the feedback rotation speed are input to the speed loop, at this time the speed loop only obtains the rotation speed loop control amount based on the second rotation speed threshold and the feedback rotation speed, but the speed loop is not involved in the control of the motor.

[0034] Optionally, in some embodiments, the step of obtaining a rotation speed loop control amount by the second rotation speed threshold and the feedback rotation speed includes the steps of obtaining a difference value between the second rotation speed threshold and the feedback rotation speed, performing a rotation speed loop adjustment on the difference value to obtain an adjustment amount, and accumulating the adjustment amounts to obtain the rotation speed loop control amount.

[0035] For example, when the feedback rotation speed is higher than the first rotation speed threshold, the motor is continuously controlled to operate at constant power, and at the same time, the speed loop only performs calculation and does not control, and at this time, the speed loop obtains a rotation speed difference value between the second rotation speed threshold and the feedback rotation speed, performs PI (Proportional Integral) adjustment or PID (Proportional Integration Differentiation) adjustment on the rotation speed difference value to obtain an adjustment amount, and accumulates the obtained adjustment amounts to obtain a rotation speed loop control amount.

[0036] Optionally, the speed loop may include a stepped PI or PID regulator, but whatever type of regulator is used, the final output control variable of the speed loop is full stepped.

[0037] Take the speed loop as an example, where the speed loop includes a step-up PID regulator. The output of the step-up PID regulator is shown in equation (1).

[0038] △u(k)=Kp×[e(k)-e(k-1)]+Ki×e(k)+Kd×[e(k)-2e(k-1)-e(k-2)] (1)

[0039] Here, Δu(k) is the output amount of the boost PID regulator at time k, Kp is a proportional coefficient, Ki is an integral coefficient, Kd is a differential coefficient, and e(k), e(k-1), and e(k-2) are the rotational speed difference values ​​between the second rotational speed threshold and the feedback rotational speed at time k, k-1, and k-2, respectively.

[0040] Since the speed loop outputs a full amount, the output amount △u(k) of the incremental PID regulator at time k is obtained, and then the output amount △u(k) is added again to obtain the speed loop control amount.

[0041] In addition, the speed loop can be a position type PI or PID regulator, and since the output of the incremental type PI or PID regulator is a full amount type, the output adjustment amount does not need to be accumulated, as long as the incremental type PI or PID regulator is in a calculation state. Take the speed loop as an example, where the speed loop includes a position type PID regulator, and the output of the position type PID regulator is shown in formula (2).

[0042] u(k)=Kp×e(k)+Ki×Σe(i)+Kd×[e(k)-e(k-2)], where i=0,...,k (2)

[0043] Here, u(k) is the output amount of the position PID regulator at time k, Kp is a proportional coefficient, Ki is an integral coefficient, Kd is a differential coefficient, e(k) and e(k-1) are the rotational speed difference values ​​between the second rotational speed threshold and the feedback rotational speed at time k and time k-1, respectively, and Σ indicates that a sum is to be calculated.

[0044] Step S3: when it is determined that the feedback rotation speed is higher than the second rotation speed threshold, the second rotation speed threshold is set as the default variable of the rotation speed loop, the control variable of the rotation speed loop is set as the initial control variable of the rotation speed loop, and the motor is controlled to operate at a constant rotation speed.

[0045] Here, the constant rotation speed operation of the motor means that the feedback rotation speed during the operation of the motor does not change basically, that is, the feedback rotation speed basically coincides with the target rotation speed, and the target rotation speed here is the second rotation speed threshold value, that is, when the feedback rotation speed of the motor rises to the second rotation speed threshold value, the second rotation speed threshold value is set as the target rotation speed at this time, and the motor is controlled to operate at a constant rotation speed, thereby preventing the rotation speed of the motor from continuing to rise and becoming too high for a long time, which would cause damage to the rotor system of the motor.

[0046] For example, during the constant power operation of the motor, when the feedback rotation speed is higher than the second rotation speed threshold, the power loop and the current loop of the motor control system are disconnected, and the rotation speed loop is connected to the current loop, so that the rotation speed loop starts to participate in the control of the motor. At the time when the control starts, the rotation speed loop control amount calculated in step S2 is input to the current loop as the initial control amount of the speed loop, and the current loop performs subsequent control, thereby realizing a smooth switch from the constant power operation to the constant rotation speed operation of the motor, and the second rotation speed threshold is input to the speed loop as the target rotation speed as the default amount of the speed loop, and the motor is controlled to operate at the constant rotation speed. Here, when the motor is controlled to operate at the constant rotation speed, the speed loop obtains the rotation speed difference value between the second rotation speed threshold and the feedback rotation speed, performs PI or PID adjustment on the rotation speed difference value to output the control amount, and the control amount is input to the current loop, and the current loop performs subsequent control, thereby realizing the constant rotation speed control of the motor.

[0047] In the above embodiment, when the motor is controlled to operate at constant power, if the feedback rotation speed of the motor is higher than the first rotation speed threshold, the motor is controlled to continue operating at constant power; at the same time, the speed loop is put into a continuous calculation state, so that when the feedback rotation speed is higher than the second rotation speed threshold, the calculation result is used as the initial control amount of the rotation speed loop, and the second rotation speed threshold is used as the default amount, and the motor is controlled to operate at constant rotation speed. This not only effectively prevents the motor from being damaged due to its rotation speed being too high, but also realizes the motor to be smoothly switched from constant power operation to constant rotation speed operation, thereby improving the safety and reliability of the motor operation.

[0048] Further, referring to FIG. 3, the above motor control method may further include the following steps:

[0049] Step S4: In the process of controlling the motor to operate at a constant rotation speed, the time for constant rotation speed operation and the control amount of the power loop are obtained.

[0050] For example, when the motor is operated at a constant speed, the timer records the time when the motor is operated at a constant speed and simultaneously obtains the control variable of the power loop, that is, when the motor is operated at a constant speed, the power loop only performs calculations and is not involved in control, and at this time, the power loop calculates the control variable according to the target power and the DC bus voltage, that is, the control variable is obtained by dividing the target power by the DC bus voltage.

[0051] Step S5: when it is determined that the time is lower than the time threshold and the control variable of the rotation speed loop is higher than the control variable of the power loop, control the motor to operate at constant power.

[0052] That is, when the control amount of the rotational speed loop becomes higher than the control amount of the power loop within a short period of time, it indicates that the load of the motor returns to normal, and at this time the rotational speed loop and the current loop of the motor control system are disconnected, and the power loop is connected to the current loop, thereby controlling the motor to operate at constant power.

[0053] Optionally, in some embodiments, a difference value between the control amount of the rotation speed loop and the control amount of the power loop can be obtained, and when the control amount of the rotation speed loop is higher than the control amount of the power loop, and the difference value is smaller than a preset threshold, and the time is lower than a time threshold, the motor is controlled to operate at constant power, where the difference value can be set to a maximum value that does not cause an impact when switching the operation of the motor, thereby realizing the motor to smoothly switch from constant rotation speed operation to constant power operation.

[0054] In addition, the time threshold can be determined according to the performance parameters of the motor, such as one or more of the temperature rise, heat dissipation status, and rotor load capacity of the motor.

[0055] Step S6, when it is determined that the time is not lower than the time threshold, control the motor to run at a reduced speed or to stop.

[0056] In other words, if the control amount of the rotation speed loop is always lower than the control amount of the power loop within a long period of time, it indicates that the load on the motor will not recover and it is possible that the motor will always be in a light-load state. At this time, the motor can be controlled to operate at a reduced speed or stopped, thereby preventing the motor from being in a light-load, high-speed operating state for a long period of time.

[0057] As a specific embodiment, as shown in FIG. 4, the motor control method may include the following steps.

[0058] In step S301, the motor is controlled to operate at constant power.

[0059] Step S302: obtain the feedback rotation speed of the motor.

[0060] Step S303: determine whether the feedback rotation speed is higher than the first rotation speed threshold, if yes, execute step S304, if no, return to step S301;

[0061] In step S304, a rotation speed loop control amount is obtained according to the second rotation speed threshold and the feedback rotation speed.

[0062] Step S305: determine whether the feedback rotation speed is higher than the second rotation speed threshold value, if yes, execute step S306, if no, return to step S301;

[0063] In step S306, the motor is controlled to operate at a constant rotation speed.

[0064] In step S307, the constant speed operation time and the control amount of the power loop are obtained.

[0065] Step S308: Determine whether the time of constant speed operation is lower than the time threshold value. If it is lower, execute step S309; ​​if not, execute step S311.

[0066] Step S309: determine whether the control amount of the rotation speed loop is higher than the control amount of the power loop, if it is higher, execute step S310, if it is not higher, return to step S306;

[0067] In step S310, the motor is controlled to operate at constant power.

[0068] Step S311: Control the motor to run at a reduced speed or stop the motor.

[0069] From the above, according to the motor control method in the embodiment of the present disclosure, in the process of controlling the motor to operate at constant power, a feedback rotation speed of the motor is obtained, and when the feedback rotation speed is higher than a first rotation speed threshold, a rotation speed loop control variable is obtained according to a second rotation speed threshold and the feedback rotation speed, and when the feedback rotation speed is higher than the second rotation speed threshold, the second rotation speed threshold is set as a preset variable of the rotation speed loop, and the rotation speed loop control variable is set as an initial control variable of the rotation speed loop, so as to control the motor to operate at a constant rotation speed. In this way, when the motor is operated at constant power, after the rotation speed suddenly rises due to the influence of factors such as extreme conditions, the safety and reliability of the operation of the rotor system of the motor can not only be guaranteed, but also the motor can be smoothly switched from constant power operation to constant rotation speed operation, reducing the impact of switching the control method.

[0070] Corresponding to the above embodiment, the present disclosure further provides a computer-readable storage medium.

[0071] A computer-readable storage medium according to an embodiment of the present disclosure stores a motor control program, which, when executed by a processor, realizes the motor control method described above.

[0072] According to the computer-readable storage medium in the embodiment of the present disclosure, by implementing the above motor control method, damage caused by the motor rotating at too high a speed can not only be effectively avoided, but also the motor can be smoothly switched from constant power operation to constant rotational speed operation.

[0073] Corresponding to the above embodiment, the present disclosure further provides a motor controller.

[0074] FIG. 5 is a block schematic diagram of a motor controller according to one embodiment of the present disclosure.

[0075] As shown in FIG. 5, the motor controller 100 in an embodiment of the present disclosure includes a memory 110, a processor 120, and a motor control program stored in the memory 110 and executable by the processor 120, and when the processor 120 executes the program, the above-mentioned motor control method is realized.

[0076] According to the motor controller in the embodiment of the present disclosure, by implementing the above motor control method, it is possible not only to effectively prevent the motor from being damaged due to its rotational speed being too high, but also to smoothly switch the motor from constant power operation to constant rotational speed operation.

[0077] Corresponding to the above embodiment, the present disclosure further provides a motor control device.

[0078] FIG. 6 is a block schematic diagram of a motor control device according to one embodiment of the present disclosure.

[0079] As shown in FIG. 6 , the motor controller 200 in accordance with an embodiment of the present disclosure may include an acquisition module 210 and a control module 220 .

[0080] Here, the acquisition module 210 is used for acquiring a feedback rotation speed of the motor. In the process of controlling the motor to operate at constant power, when the control module 220 determines that the feedback rotation speed is higher than the first rotation speed threshold, it acquires a rotation speed loop control amount according to the second rotation speed threshold and the feedback rotation speed, and when it determines that the feedback rotation speed is higher than the second rotation speed threshold, it takes the second rotation speed threshold as the default amount of the rotation speed loop and the rotation speed loop control amount as the initial control amount of the rotation speed loop, and uses it to control the motor to operate at a constant rotation speed, where the second rotation speed threshold is higher than the first rotation speed threshold.

[0081] According to an embodiment of the present disclosure, the control module 220 obtains a rotation speed loop control amount according to the second rotation speed threshold and the feedback rotation speed, specifically, is used for obtaining a difference value between the second rotation speed threshold and the feedback rotation speed, performing rotation speed loop adjustment on the difference value to obtain an adjustment amount, and accumulating the adjustment amount to obtain the rotation speed loop control amount.

[0082] According to an embodiment of the present disclosure, the control module 220 is further used in the process of controlling the motor to operate at a constant rotational speed to obtain a time of constant rotational speed operation and a control variable of a power loop, and when it is determined that the time is lower than a time threshold and the control variable of the rotational speed loop is higher than the control variable of the power loop, to control the motor to operate at a constant power.

[0083] According to one embodiment of the present disclosure, the control module 220 is further used to control the motor to run at a reduced speed or to stop when it determines that the time is not below the time threshold.

[0084] According to an embodiment of the present disclosure, the time threshold is determined according to at least one of the following: temperature rise of the motor, heat dissipation condition, and rotor load capacity.

[0085] According to one embodiment of the present disclosure, the controlled variable of the power loop is the ratio between the target power and the DC bus voltage.

[0086] For details not disclosed in the motor control device in the embodiment of the present disclosure, please refer to the details disclosed in the motor control method in the embodiment of the present disclosure, and detailed explanations will be omitted here.

[0087] According to the motor control device in the embodiment of the present disclosure, in the process of controlling the motor to operate at constant power, when the feedback rotational speed of the motor is higher than the first rotational speed threshold, the control module obtains a rotational speed loop control variable according to the second rotational speed threshold and the feedback rotational speed, and when the feedback rotational speed is higher than the second rotational speed threshold, the second rotational speed threshold is set as a default variable of the rotational speed loop, and the rotational speed loop control variable is set as an initial control variable of the rotational speed loop, so as to control the motor to operate at constant rotational speed, which not only effectively prevents damage caused by the motor's rotational speed being too high, but also realizes smooth switching from constant power operation to constant rotational speed operation of the motor.

[0088] It should be noted that the logic and / or steps depicted in the flow charts or otherwise described herein may be viewed, for example, as an executable sequential listing of instructions to achieve logical functions, and may be embodied in any computer readable medium for use with an instruction execution system, apparatus, or device (including, for example, a computer-based system, a processor system, or a system that retrieves and executes instructions from other instruction execution systems, apparatus, or devices), or for use in conjunction with such instruction execution systems, apparatus, or devices. For purposes of this specification, a "computer readable medium" may include any program capable of containing, storing, communicating, propagating, or transmitting an instruction execution system, apparatus, or device, or a device for use in conjunction with such instruction execution systems, apparatus, or devices. More specific examples of computer readable media (non-exhaustive list) include electrical connections having one or more wires (electronic devices), portable computer disk enclosures (magnetic devices), random access memory (RAM), read-only memory (ROM), programmable erasable read-only memory (EPROM or flash memory), fiber optic devices, and portable CD-ROMs (CD-ROMs). It may also be a computer readable medium, such as paper or other suitable medium onto which the program may be printed, for example by optically scanning the paper or other medium and then editing, interpreting or otherwise processing as required to obtain the program in electronic form and storing it in computer memory.

[0089] It should be noted that each part of the present disclosure can be realized by hardware, software, firmware, or a combination thereof. In the above implementation, several steps or methods can be realized by software or firmware stored in a memory and executed by an appropriate command execution system. For example, when realized by hardware, as in other implementations, it can be realized by any one or combination of discrete logic circuits having logic circuits for implementing logic functions on data signals, application specific integrated circuits having appropriate combinational logic circuits, programmable gate arrays (PGAs), and field programmable gate arrays (FPGAs), etc., which are known in the art.

[0090] In the present description, reference to the reference terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples" means that the specific features, structures, materials, or characteristics described in the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present description, expressions used to indicate the meaning of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0091] Additionally, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply a relative importance or to specify the number of technical features being indicated. Thus, a feature qualified as "first" or "second" may specify or imply the inclusion of at least one of that feature. In the description of this disclosure, "plurality" means at least two, e.g., two, three, etc., unless otherwise clearly and specifically limited.

[0092] In this disclosure, unless otherwise clearly specified and limited, the terms "attached," "connected," "connected," "fixed," and the like should be interpreted broadly, for example, as a fixed connection, a detachable connection or integration, a mechanical connection, an electrical connection, a direct connection, an indirect connection through a medium, an internal communication between two parts, or an interactive relationship between two parts. Those skilled in the art can understand the specific meaning of the above terms in the present disclosure according to the specific circumstances.

[0093] Although the above has already shown and described embodiments of the present disclosure, the above embodiments are illustrative and should not be construed as limiting the present disclosure, and those skilled in the art may make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present disclosure.

Claims

1. obtaining a feedback rotation speed of the motor during a process of controlling the motor to operate at constant power; When it is determined that the feedback rotation speed is higher than a first rotation speed threshold, obtaining a rotation speed loop control variable according to a second rotation speed threshold higher than the first rotation speed threshold and the feedback rotation speed; when it is determined that the feedback rotation speed is higher than the second rotation speed threshold, setting the second rotation speed threshold as a default variable of a rotation speed loop, setting the rotation speed loop control variable as an initial control variable of the rotation speed loop, and controlling the motor to operate at a constant rotation speed.

2. The step of acquiring a rotation speed loop control variable based on the second rotation speed threshold value and the feedback rotation speed includes: Obtaining a difference value between the second rotational speed threshold and the feedback rotational speed; performing a rotation speed loop adjustment on the difference value to obtain an adjustment amount; 2. The method of claim 1, further comprising: accumulating said adjustment amounts to obtain said rotational speed loop control variable.

3. In the process of controlling the motor to operate at a constant rotation speed, a time for operating at a constant rotation speed and a control amount for a power loop are obtained; 3. The motor control method of claim 1, further comprising: controlling the motor to operate at constant power when it is determined that the time is lower than a time threshold and the control variable of the rotation speed loop is higher than the control variable of the power loop.

4. The motor control method of claim 3 , further comprising the step of controlling the motor to run at a reduced speed or to stop when it is determined that the time is not less than the time threshold.

5. The motor control method according to claim 3 , wherein the time threshold is determined according to at least one of the following: a temperature rise of the motor, a heat dissipation situation, and a rotor load capacity.

6. 4. The motor control method of claim 3, wherein the controlled variable of the power loop is a ratio between a target power and a DC bus voltage.

7. A computer-readable storage medium storing a motor control program, the computer-readable storage medium implementing the motor control method according to any one of claims 1 to 6 when the motor control program is executed by a processor.

8. A motor controller comprising a memory, a processor, and a motor control program stored in the memory and executable by the processor, the motor control program being executed by the processor when the processor executes the motor control method according to any one of claims 1 to 6.

9. an acquisition module for acquiring a feedback rotation speed of the motor; a control module used to obtain a rotational speed loop control variable by a second rotational speed threshold higher than the first rotational speed threshold and the feedback rotational speed when it is determined that the feedback rotational speed is higher than a first rotational speed threshold, and to control the motor to operate at a constant rotational speed when it is determined that the feedback rotational speed is higher than the second rotational speed threshold, the second rotational speed threshold being a default variable of a rotational speed loop, and the rotational speed loop control variable being an initial control variable of the rotational speed loop.

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