CN111058224A

CN111058224A - Motor operation control method and system, drum washing machine and storage medium

Info

Publication number: CN111058224A
Application number: CN201811198553.7A
Authority: CN
Inventors: 徐磊; 秦向南; 龚黎明; 赵小安
Original assignee: Guangdong Welling Motor Manufacturing Co Ltd; Midea Welling Motor Technology Shanghai Co Ltd
Current assignee: Guangdong Welling Motor Manufacturing Co Ltd; Midea Welling Motor Technology Shanghai Co Ltd
Priority date: 2018-10-15
Filing date: 2018-10-15
Publication date: 2020-04-24
Anticipated expiration: 2038-10-15
Also published as: CN111058224B

Abstract

The invention provides a motor operation control method and system for a drum washing machine, the drum washing machine and a computer readable storage medium. The method comprises the following steps: controlling a rotor of the motor to rotate in an accelerating manner towards a first rotating direction, acquiring the current rotating speed of the motor, and controlling the motor to continuously change from a first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time; and when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time period, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed without stopping time, wherein the rotating speed directions of the first target rotating speed and the second target rotating speed are opposite. According to the invention, in the reciprocating switching process between the first target speed and the second target speed when the washing machine washes, the stay time at zero speed in the related technology is saved, so that the washing time of clothes is reduced, and the washing efficiency is improved.

Description

Motor operation control method and system, drum washing machine and storage medium

Technical Field

The present invention relates to the field of washing machine control and motor control, and in particular, to a motor operation control method for a drum washing machine, a motor operation control system for a drum washing machine, and a computer-readable storage medium.

Background

At present, a related drum washing machine is designed by simulating the principle of hammering and hitting clothes, a motor controls a drum of the washing machine to rotate, and the clothes are beaten in the drum to clean the clothes. At present, the washing machines on the market control the motor to periodically change from positive rotation to stop to reverse rotation to stop so as to drive the drum to rotate, thereby realizing washing. Specifically, fig. 1 illustrates a control mode of a motor in a related art drum washing machine. In the washing mode of periodically changing the forward rotation, the stop, the reverse rotation and the stop of the motor, the stop time and the forward rotation time are set by a preset ratio, however, the motor control method occupies a large amount of washing time in the washing process due to the existence of the stop time, which causes the washing time to be too long and influences the use experience of a user.

Therefore, a need exists for a motor control method that controls the operation of the motor to reduce the stop time for switching between forward and reverse rotation of the motor, thereby reducing the laundry washing time.

Disclosure of Invention

The present invention is directed to solving at least one of the problems in the related art or the related art.

To this end, a first aspect of the present invention provides a motor operation control method for a drum washing machine.

In a second aspect of the present invention, a motor operation control system for a drum washing machine is provided.

A third aspect of the present invention provides a drum washing machine.

A fourth aspect of the present invention is to provide a computer-readable storage medium.

In view of the above, according to a first aspect of the present invention, there is provided a motor operation control method for a drum washing machine, comprising: controlling a rotor of the motor to rotate in an accelerating manner towards a first rotating direction, acquiring the current rotating speed of the motor, and controlling the motor to continuously change from a first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time; and when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time period, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed without stopping time, wherein the rotating speed directions of the first target rotating speed and the second target rotating speed are opposite.

The invention provides a motor operation control method for a drum washing machine, which is characterized in that after a rotor of a motor is controlled to rotate for a first preset time at a first target rotating speed according to a first rotating direction, the motor is controlled to continuously change the rotating speed from the first target rotating speed to a second target rotating speed. In the process, the stop time in the related art is not reserved, but the motor is controlled to be directly changed from the first target rotating speed to the second target rotating speed with the opposite rotating direction, and the motor is not stopped for a certain time when the rotating speed is zero. Similarly, when the rotating speed of the motor reaches the second target rotating speed and runs for a second preset time period, the motor is controlled to continuously change from the second target rotating speed to the first target rotating speed with the opposite rotating direction, and the motor does not stop rotating for a certain time period when the rotating speed is zero. Therefore, in the reciprocating switching process between the first target speed and the second target speed when the washing machine washes clothes, the stay time at zero speed in the related technology is saved, so that the washing time of the clothes is reduced, the washing efficiency is improved, and the use experience of a user is improved.

In addition, the motor operation control method for the drum washing machine in the above technical scheme provided by the present invention may further have the following additional technical features:

in the above technical solution, preferably, the step of obtaining the current rotation speed of the motor specifically includes: acquiring a driving voltage and a current of a motor; calculating a rotor flux linkage of the motor according to the driving voltage and the current, and calculating a rotor position of the motor according to the rotor flux linkage; and calculating the current rotating speed of the motor according to the rotor position.

In the technical scheme, the current rotating speed of the motor is calculated by obtaining the driving voltage and the current of the motor, specifically, the rotor flux linkage of the current motor is calculated by using the driving voltage and the current, the rotor position of the motor is calculated by using a flux linkage observation mode, and the current rotating speed of the current rotor is calculated by using the calculated rotor position. The current rotating speed can be observed in real time in a flux linkage observation mode, the current rotating speed can be determined only by detecting the driving voltage and sampling the current, the calculation process is simple, and the motor can be controlled conveniently.

In any of the above technical solutions, preferably, the step of calculating the rotor flux linkage of the motor specifically includes: and calculating the back electromotive force of the motor by adopting a voltage model-based stator flux linkage estimation method, performing phase compensation and integral filtering on the back electromotive force, and calculating to obtain the rotor flux linkage.

The method comprises the following specific steps of calculating back electromotive forces of the motor on a α shaft and a β shaft based on the stator and the detection α shaft current and β shaft current of a voltage model and the resistance of the motor, performing phase compensation on the calculated back electromotive forces based on the rotation angular frequency and the filtering frequency of the motor to obtain the compensated back electromotive forces on the α shaft and the β shaft, performing integral filtering on the back electromotive forces to obtain a stator flux of the motor, calculating the rotor flux of the motor according to a relation formula of the stator flux and the rotor flux to calculate the rotor position of the motor according to the rotor flux, further determining the current rotation speed of the rotor of the motor, and realizing the control of the motor.

In any of the above technical solutions, preferably, the back electromotive force of the motor is calculated by the following formula:

wherein E is_αCounter-potential for motor α shaft, E_βCounter-potential for motor β shaft, U_αIs motor α shaft voltage, U_βIs the motor β shaft voltage, I_αIs motor α shaft current, I_βMotor β shaft current, R motor resistance.

In the technical scheme, the shaft voltage U of the motor α is obtained_αMotor β shaft voltage U_βMotor resistance R and motor α shaft current I_αMotor β shaft current I_βThe counter potential E of the shaft of the motor α can be calculated_αAnd motor β shaft counter-potential E_βThe method can be obtained without a complex calculation process.

In any of the above technical solutions, preferably, the step of performing phase compensation and integral filtering on the back electromotive force is calculated by the following formula:

wherein the phase compensation formula is as follows:

wherein, E'_αIs motor α shaft compensated voltage, E'_βCompensated voltage for motor β axis, E_αCounter-potential for motor α shaft, E_βIs motor β shaft back electromotive force, omega_cFor filtering frequency, omega_eFor angular frequency of rotation of the motorRate;

the calculation formula of the integral filtering is as follows:

wherein,

is the flux linkage of the α axis,

is the flux linkage of the β axes, and S is the laplace operator.

In this solution, the flux linkage of the α axis

β magnetic linkage of axes

Can directly pass the filtering frequency omega_cLaplace operator S and motor α shaft compensated voltage E'_αβ shaft compensated Voltage E'_βThe method can be obtained by direct calculation without complex calculation process.

In any of the above technical solutions, preferably, the rotor flux linkage is calculated by the following formula:

wherein, the rotor flux linkage

And

respectively α axis flux linkage and β axis rotor flux linkage, L_qIs the inductance of the rotor of an electric machine, I_αIs motor α shaft current, I_βIs the motor β shaft current.

In the technical scheme, the calculation is carried out to obtainα magnetic linkage of axes

β magnetic linkage of axes

And inductance L of the motor rotor_qα Axis Current I_αMotor β shaft current I_βDirectly calculating to obtain rotor flux linkage

And

rotor flux linkage obtained by pair calculation

And

and performing arc tangent calculation to obtain the position of the rotor, thereby determining the rotating speed of the rotor.

In any of the above technical solutions, preferably, the motor operation control method further includes: the step of controlling the motor to continuously change from a first target rotating speed to a second target rotating speed specifically comprises the following steps: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range; the step of controlling the motor to continuously change from the second target rotating speed to the first target rotating speed specifically comprises: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold value, controlling the rotor of the motor to accelerate to a first target rotating speed in a first rotating direction; the second preset threshold is 0, or the second preset threshold is any value of which the difference value with 0 is within a second preset range.

In the technical scheme, in the process that the motor continuously runs from the first target rotating speed to the second target rotating speed, the process of first decelerating and then accelerating is actually performed, and the first preset threshold is a node in the process of switching the decelerating operation to the accelerating operation. When the current rotating speed of the motor is detected to be reduced to a first preset threshold value, the motor is accelerated again until a second target rotating speed is reached, wherein the first preset threshold value can be 0 or any value fluctuating above 0, specifically, when the rotating speed of the motor rotor is 0, namely the current rotor is just ready to stop from the first rotating direction, the rotor is controlled to rotate towards the second rotating direction, and therefore the situation that the rotor is in a stop state is avoided. Similarly, the second preset threshold value also exists during the continuous operation of the motor from the second target rotation speed to the first target rotation speed. The second preset threshold has the same function as the first preset threshold, and is not described herein again.

It is worth pointing out that, when setting the first preset threshold, the setting is performed through the relationship between the electrical frequency, the rotation speed and the number of pole pairs of the motor, the specific electrical frequency is equal to the product of the rotation speed and the number of pole pairs of the motor, and the rotation speed, namely the first preset threshold, is indirectly set through the setting of the electrical frequency. Similarly, the second predetermined threshold is set in the same manner. Wherein the electrical frequency is a supply frequency.

In any of the above technical solutions, preferably, the step of controlling the rotor of the motor to accelerate to the second target rotation speed in the second rotation direction includes: controlling the rotor to step to a second target rotating speed; and/or controlling the rotor of the motor to accelerate to a first target rotating speed in a first rotating direction, specifically: and controlling the rotor to step to a first target rotating speed.

In this technical scheme, controlling the rotor of the motor to accelerate to the second target rotation speed in the second rotation direction specifically comprises: and controlling the rotor of the motor to step to a second target rotation speed, specifically, controlling the rotation speed of the rotor to climb to the second target rotation speed in a time period, for example, applying a larger driving voltage and/or driving current to the rotor of the motor to provide a larger acceleration to the rotor, controlling the rotation speed of the rotor to step to the second target rotation speed, where one time period may be 1 second or a time period of several seconds, and further controlling the rotor of the motor to rapidly switch from the first rotation direction to the second rotation direction. And similarly, the rotor of the motor is controlled to step to the first target rotating speed by controlling the rotor to rotate from the second rotating direction to the first rotating direction and accelerate to the first target rotating speed.

In any of the above technical solutions, preferably, the motor operation control method further includes: acquiring a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to the second target rotating speed; the preset speed curve is generated according to a first target rotating speed, a second target rotating speed, a first preset time length and a second target time length; and searching a preset rotating speed corresponding to the current moment in a preset speed curve according to the current moment corresponding to the current rotating speed, and correcting the current rotating speed to be the preset rotating speed when the current rotating speed has deviation from the preset rotating speed.

In the technical scheme, a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to the second target rotating speed is obtained, the preset rotating speed directly corresponding to the corresponding moment in the preset speed curve is searched according to the current moment corresponding to the calculated current rotating speed, and whether the current rotating speed and the preset rotating speed have deviation or not is judged, wherein the interval corresponds to the interval from the initial value (such as 0) to the second target rotating speed. And when the deviation exists between the current rotating speed and the preset rotating speed, correcting the current rotating speed to be the preset rotating speed. The step of correcting the current rotating speed to the preset rotating speed is set, so that the accuracy of controlling the operation of the motor is ensured, the control motor is prevented from operating at the first preset rotating speed, the actual motor is smaller than the first preset rotating speed, the motor is prevented from stalling due to the fact that the motor does not operate according to a rotating speed-time curve, and meanwhile, the motor is prevented from being damaged due to the fact that the rotating speed is deviated from the target rotating speed when the motor is reversed.

In any of the above technical solutions, preferably, the step of correcting the current rotation speed to be the preset rotation speed specifically includes: calculating a driving torque according to a difference value between a preset rotating speed and a current rotating speed; and acquiring the current of the motor, calculating a driving voltage according to the current and the driving torque, and controlling the motor to drive the rotor of the motor to rotate by the driving voltage.

In the technical scheme, a difference value between the preset rotating speed to be obtained and the current rotating speed is calculated, the driving torque is calculated according to the calculated difference value, the current of the motor is obtained, the driving voltage for driving the motor to operate is calculated according to the current and the calculated driving torque, and the driving voltage is input into the motor. So that the motor is driven to operate according to the input driving voltage, and further the correction of the preset rotating speed and the current rotating speed is realized. The mode of controlling the motor to correct only needs to obtain the current and does not need to obtain other parameters, so that the data processing process is reduced, the correcting speed is accelerated, the speed reduction time of a motor rotor is reduced, the efficient utilization of the motor is realized, and the washing time of clothes is reduced.

According to a second aspect of the present invention, there is provided a motor operation control system for a drum washing machine, comprising: a memory for storing a computer program; a processor for executing a computer program to: controlling a rotor of the motor to rotate in an accelerating manner towards a first rotating direction, acquiring the current rotating speed of the motor, and controlling the motor to continuously change from a first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time; when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed, wherein no stop time exists; and the rotating speed direction of the first target rotating speed is opposite to that of the second target rotating speed.

The invention provides a motor operation control system for a drum washing machine, which comprises a processor and a memory, wherein the processor executes an executable program stored in the memory to: and after a rotor of the motor is controlled to rotate for a first preset time at a first target rotating speed according to a first rotating direction, the motor is controlled to continuously change the rotating speed from the first target rotating speed to a second target rotating speed. In the process, the stop time in the related art is not reserved, but the motor is controlled to be directly changed from the first target rotating speed to the second target rotating speed with the opposite rotating direction, and the motor is not stopped for a certain time when the rotating speed is zero. Similarly, when the rotating speed of the motor reaches the second target rotating speed and runs for a second preset time period, the motor is controlled to continuously change from the second target rotating speed to the first target rotating speed with the opposite rotating direction, and the motor does not stop rotating for a certain time period when the rotating speed is zero. Therefore, in the reciprocating switching process between the first target speed and the second target speed when the washing machine washes clothes, the stay time at zero speed in the related technology is saved, so that the washing time of the clothes is reduced, the washing efficiency is improved, and the use experience of a user is improved.

In addition, the motor operation control system for the drum washing machine in the above technical scheme provided by the present invention may further have the following additional technical features:

in the foregoing technical solution, preferably, the processor is further specifically configured to execute a computer program to control the motor to continuously change from the first target rotation speed to the second target rotation speed, and specifically includes: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range; the processor is further configured to execute a computer program to implement the step of controlling the motor to continuously change from the second target rotation speed to the first target rotation speed, and specifically includes: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold value, controlling the rotor of the motor to accelerate to a first target rotating speed in a first rotating direction; the second preset threshold is 0, or the second preset threshold is any value of which the difference value with 0 is within a second preset range.

In any of the above technical solutions, preferably, the processor is further configured to execute a computer program to implement a step of controlling the rotor of the motor to accelerate to the second target rotation speed in the second rotation direction, and specifically includes: controlling the rotor to step to a second target rotating speed; and/or the processor is further configured to execute a computer program to implement the step of controlling the rotor of the electric machine to accelerate to the first target rotational speed in the first rotational direction, specifically: and controlling the rotor to step to a first target rotating speed.

In any of the above technical solutions, preferably, the processor is specifically configured to execute a computer program to: acquiring a driving voltage and a current of a motor; calculating a rotor flux linkage of the motor according to the driving voltage and the current, and calculating a rotor position of the motor according to the rotor flux linkage; and calculating the current rotating speed of the motor according to the rotor position.

In any of the above technical solutions, preferably, the processor is specifically configured to execute a computer program to: and calculating the back electromotive force of the motor by adopting a voltage model-based stator flux linkage estimation method, performing phase compensation and integral filtering on the back electromotive force, and calculating to obtain the rotor flux linkage.

The processor is specifically used for executing a computer program to calculate back electromotive forces of the motor on a α shaft and a β shaft based on the stator and the detection α shaft current and β shaft current of the voltage model and the resistance of the motor, perform phase compensation on the calculated back electromotive forces based on the rotation angular frequency of the motor and the filtering frequency to obtain the back electromotive forces on a α shaft and a β shaft after compensation, perform integral filtering on the back electromotive forces to obtain a stator flux linkage of the motor, and calculate a rotor flux linkage of the motor according to a relation formula of the stator flux linkage and the rotor flux linkage to calculate the rotor position of the motor according to the rotor flux linkage so as to determine the current rotating speed of the rotor of the motor and realize the control of the motor.

wherein the phase compensation formula is as follows:

wherein, E'_αIs motor α shaft compensated voltage, E'_βCompensated voltage for motor β axis, E_αCounter-potential for motor α shaft, E_βIs motor β shaft back electromotive force, omega_cFor filtering frequency, omega_eIs the motor rotation angular frequency;

the calculation formula of the integral filtering is as follows:

wherein,

is the flux linkage of the α axis,

is the flux linkage of the β axes, and S is the laplace operator.

In this solution, the flux linkage of the α axis

β magnetic linkage of axes

wherein, the rotor flux linkage

And

In this embodiment, the flux linkage of the α axis is obtained by calculation

β magnetic linkage of axes

And

rotor flux linkage obtained by pair calculation

And

In any of the above technical solutions, preferably, the processor is further configured to execute the computer program to: acquiring a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to the second target rotating speed; the preset speed curve is generated according to a first target rotating speed, a second target rotating speed, a first preset time length and a second target time length; and searching a preset rotating speed corresponding to the current moment in a preset speed curve according to the current moment corresponding to the current rotating speed, and correcting the current rotating speed to be the preset rotating speed when the current rotating speed has deviation from the preset rotating speed.

In any of the above technical solutions, preferably, the processor is specifically configured to execute a computer program to: calculating a driving torque according to a difference value between a preset rotating speed and a current rotating speed; and acquiring the current of the motor, calculating a driving voltage according to the current and the driving torque, and controlling the motor to drive the rotor of the motor to rotate by the driving voltage.

According to a third aspect of the present invention, there is provided a drum washing machine, wherein the drum washing machine comprises any one of the above-mentioned motor operation control systems for the drum washing machine.

The drum washing machine provided by the invention comprises the motor operation control system for the drum washing machine in any technical scheme, so that the drum washing machine has all the beneficial technical effects of the motor operation control system for any drum washing machine, and the details are not repeated.

According to a fourth aspect of the present invention, there is provided a computer readable storage medium having stored thereon a computer program which, when executed by a processor, implements the steps of the motor operation control method for a drum washing machine as claimed in any one of the preceding claims.

The computer readable storage medium provided by the present invention, when being executed by a processor, implements the steps of the motor operation control method for a drum washing machine according to any one of the above technical solutions, and therefore, the computer readable storage medium includes all the benefits of the motor operation control method for a drum washing machine according to any one of the above technical solutions.

Additional aspects and advantages of the invention 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 invention.

Drawings

The above and/or additional aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which:

fig. 1 illustrates a control mode of a motor in a related art drum washing machine;

FIG. 2 is a flow chart illustrating a motor operation control method according to an embodiment of the present invention;

fig. 3 is a flow chart showing a motor operation control method according to another embodiment of the present invention;

fig. 4 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention;

fig. 5 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention;

fig. 6 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention;

fig. 7 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention;

FIG. 8 is a schematic block diagram showing the control of the rotational speed of the rotor of the motor in the present embodiment;

FIG. 9 is a schematic diagram illustrating a speed command for the rotor of the motor in the present embodiment;

FIG. 10 shows a schematic block diagram of a motor operation control system of one embodiment of the present invention;

fig. 11 shows a schematic block diagram of a laundry treating apparatus according to an embodiment of the present invention.

Detailed Description

So that the manner in which the above recited aspects, features and advantages of the present invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof which are illustrated in the appended drawings. It should be noted that the embodiments and features of the embodiments of the present application may be combined with each other without conflict.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, however, the present invention may be practiced in other ways than those specifically described herein, and therefore the scope of the present invention is not limited by the specific embodiments disclosed below.

In an embodiment of the first aspect of the present invention, a motor operation control method is provided, and fig. 2 shows a flow chart of the motor operation control method according to an embodiment of the present invention. Wherein, the method comprises the following steps:

s202, controlling a rotor of the motor to rotate in an accelerating mode towards a first rotating direction, obtaining the current rotating speed of the motor, and controlling the motor to continuously change from the first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time;

and S204, when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time period, controlling the motor to continuously change from the second target rotating speed to a first target rotating speed without stopping time, wherein the rotating speed directions of the first target rotating speed and the second target rotating speed are opposite.

Fig. 3 is a flow chart showing a motor operation control method according to another embodiment of the present invention. Wherein, the method comprises the following steps:

s302, controlling a rotor of the motor to rotate in an accelerating mode in a first rotating direction;

s304, acquiring the driving voltage and the current of the motor;

s306, calculating the rotor flux linkage of the motor according to the driving voltage and the current, and calculating the rotor position of the motor according to the rotor flux linkage;

s308, calculating the current rotating speed of the motor according to the position of the rotor;

s310, when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time, controlling the motor to continuously change from the first target rotating speed to a second target rotating speed, wherein no stop time exists;

and S312, after the rotating speed of the motor reaches the second target rotating speed and runs for a second preset time period, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed without stopping time, wherein the rotating speed directions of the first target rotating speed and the second target rotating speed are opposite.

In this embodiment, the current rotation speed of the motor is calculated by obtaining the driving voltage and the current of the motor, specifically, the rotor flux linkage of the current motor is calculated by using the driving voltage and the current, the rotor position of the motor is calculated by using flux linkage observation, and the current rotation speed of the current rotor is calculated by using the calculated rotor position. The current rotating speed can be observed in real time in a flux linkage observation mode, the current rotating speed can be determined only by detecting the driving voltage and sampling the current, the calculation process is simple, and the motor can be controlled conveniently.

Fig. 4 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention. Wherein, the method comprises the following steps:

s402, controlling the rotor of the motor to rotate in an accelerating mode in a first rotating direction;

s404, acquiring the driving voltage and the current of the motor;

s406, calculating the back electromotive force of the motor by adopting a stator flux linkage estimation method based on a voltage model according to the driving voltage and the current, performing phase compensation and integral filtering on the back electromotive force, calculating to obtain a rotor flux linkage, and calculating the rotor position of the motor according to the rotor flux linkage;

s408, calculating the current rotating speed of the motor according to the position of the rotor;

s410, when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time, controlling the motor to continuously change from the first target rotating speed to a second target rotating speed, wherein no stop time exists;

and S412, after the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time period, controlling the motor to continuously change from the second target rotating speed to a first target rotating speed without stopping time, wherein the rotating speed directions of the first target rotating speed and the second target rotating speed are opposite.

The method comprises the following specific steps of calculating back electromotive forces of the motor on a α shaft and a β shaft based on the stator and the detection α shaft current and β shaft current of the voltage model and the resistance of the motor, performing phase compensation on the calculated back electromotive forces based on the rotation angular frequency and the filtering frequency of the motor to obtain the back electromotive forces on a α shaft and a β shaft after compensation, performing integral filtering on the back electromotive forces to obtain a stator flux of the motor, and calculating the rotor flux of the motor according to a relation formula of the stator flux and the rotor flux to calculate the rotor position of the motor according to the rotor flux, further determine the current rotation speed of the rotor of the motor and realize the control of the motor.

In one embodiment of the present invention, preferably, the back electromotive force of the motor is calculated by the following formula:

In this embodiment, the shaft voltage U of the motor α is obtained_αMotor β shaft voltage U_βMotor resistance R and motor α shaft current I_αMotor β shaft current I_βThe counter potential E of the shaft of the motor α can be calculated_αAnd motor β shaft counter-potential E_βThe method can be obtained without a complex calculation process.

In one embodiment of the present invention, preferably, the step of performing phase compensation and integral filtering on the counter electromotive force is calculated by the following formula:

wherein the phase compensation formula is as follows:

the calculation formula of the integral filtering is as follows:

wherein,

is the flux linkage of the α axis,

is the flux linkage of the β axes, and S is the laplace operator.

In this embodiment, the flux linkage of the α axes

β magnetic linkage of axes

In one embodiment of the present invention, preferably, the rotor flux linkage is calculated by the following formula:

wherein, the rotor flux linkage

And

In this embodiment, the flux linkage of the α axis is obtained by calculation

β magnetic linkage of axes

And

rotor flux linkage obtained by pair calculation

And

Fig. 5 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention. Wherein, the method comprises the following steps:

s502, controlling the rotor of the motor to rotate in an accelerating mode in a first rotating direction;

s504, obtaining the driving voltage and the current of the motor;

s506, calculating the back electromotive force of the motor by adopting a stator flux linkage estimation method based on a voltage model according to the driving voltage and the current, performing phase compensation and integral filtering on the back electromotive force, calculating to obtain a rotor flux linkage, and calculating the rotor position of the motor according to the rotor flux linkage;

s508, calculating the current rotating speed of the motor according to the position of the rotor;

s510, when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time, controlling the motor to run at a reduced speed;

s512, when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction, wherein no stop time exists; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range;

s514, when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time, controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold, controlling the rotor of the motor to accelerate to the first target rotating speed in the first rotating direction, wherein no stop time exists; the rotating speed direction of the first target rotating speed is opposite to that of the second target rotating speed, the second preset threshold value is 0, or the second preset threshold value is any value of the difference value between 0 and the second preset range.

In this embodiment, the process of continuously operating the motor from the first target speed to the second target speed is actually a process of decelerating first and then accelerating, and the first preset threshold is a node point during the process of switching from the decelerating operation to the accelerating operation. When the current rotating speed of the motor is detected to be reduced to a first preset threshold value, the motor is accelerated again until a second target rotating speed is reached, wherein the first preset threshold value can be 0 or any value fluctuating above 0, specifically, when the rotating speed of the motor rotor is 0, namely the current rotor is just ready to stop from the first rotating direction, the rotor is controlled to rotate towards the second rotating direction, and therefore the situation that the rotor is in a stop state is avoided. Similarly, the second preset threshold value also exists during the continuous operation of the motor from the second target rotation speed to the first target rotation speed. The second preset threshold has the same function as the first preset threshold, and is not described herein again.

Fig. 6 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention. Wherein, the method comprises the following steps:

s602, controlling the rotor of the motor to rotate in an accelerating mode in a first rotating direction;

s604, acquiring the driving voltage and the current of the motor;

s606, calculating the back electromotive force of the motor by adopting a stator flux linkage estimation method based on a voltage model according to the driving voltage and the current, performing phase compensation and integral filtering on the back electromotive force, calculating to obtain a rotor flux linkage, and calculating the rotor position of the motor according to the rotor flux linkage;

s608, calculating the current rotating speed of the motor according to the position of the rotor;

s610, when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time, controlling the motor to run at a reduced speed;

s612, when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor to step to a second target rotating speed; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range;

s614, when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time, controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold, controlling the rotor to step to the first target rotating speed; the rotating speed direction of the first target rotating speed is opposite to that of the second target rotating speed, the second preset threshold value is 0, or the second preset threshold value is any value of the difference value between 0 and the second preset range.

In this embodiment, controlling the rotor of the motor to accelerate to the second target rotation speed in the second rotation direction is specifically performed by: and controlling the rotor of the motor to step to a second target rotation speed, specifically, controlling the rotation speed of the rotor to climb to the second target rotation speed in a time period, for example, applying a larger driving voltage and/or driving current to the rotor of the motor to provide a larger acceleration to the rotor, controlling the rotation speed of the rotor to step to the second target rotation speed, where one time period may be 1 second or a time period of several seconds, and further controlling the rotor of the motor to rapidly switch from the first rotation direction to the second rotation direction. And similarly, the rotor of the motor is controlled to step to the first target rotating speed by controlling the rotor to rotate from the second rotating direction to the first rotating direction and accelerate to the first target rotating speed.

In one embodiment of the present invention, preferably, the motor operation control method further includes: acquiring a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to the second target rotating speed; the preset speed curve is generated according to a first target rotating speed, a second target rotating speed, a first preset time length and a second target time length; and searching a preset rotating speed corresponding to the current moment in a preset speed curve according to the current moment corresponding to the current rotating speed, and correcting the current rotating speed to be the preset rotating speed when the current rotating speed has deviation from the preset rotating speed.

In this embodiment, a preset speed curve from when the motor accelerates to the first target speed to when the motor rotates to the second target speed is further obtained, the preset speed curve corresponds to an interval in which the rotation speed changes from an initial value (e.g., 0) to the second target speed, the preset rotation speed directly corresponding to the corresponding time in the preset speed curve is searched according to the current time corresponding to the calculated current rotation speed, and whether the current rotation speed and the preset rotation speed have a deviation or not is determined. And when the deviation exists between the current rotating speed and the preset rotating speed, correcting the current rotating speed to be the preset rotating speed. The step of correcting the current rotating speed to the preset rotating speed is set, so that the accuracy of controlling the operation of the motor is ensured, the control motor is prevented from operating at the first preset rotating speed, the actual motor is smaller than the first preset rotating speed, the motor is prevented from stalling due to the fact that the motor does not operate according to a rotating speed-time curve, and meanwhile, the motor is prevented from being damaged due to the fact that the rotating speed is deviated from the target rotating speed when the motor is reversed.

In an embodiment of the present invention, preferably, the step of correcting the current rotation speed to be the preset rotation speed specifically includes: calculating a driving torque according to a difference value between a preset rotating speed and a current rotating speed; and acquiring the current of the motor, calculating a driving voltage according to the current and the driving torque, and controlling the motor to drive the rotor of the motor to rotate by the driving voltage.

Fig. 7 is a flowchart illustrating a motor operation control method according to still another embodiment of the present invention. Wherein, the method comprises the following steps:

s702, presetting the rotation speed N1 and the running time T1 of the rotation speed N1; presetting a rotation speed N2 and a running time T2 of the rotation speed N1, wherein N1 and N2 are opposite in positive and negative;

s704, controlling the motor to rotate, accelerating until the rotating speed reaches N1, and keeping the rotating speed N1 running for a time T1;

s706, after the time T1 is up, controlling the motor to pass through at zero speed, decelerating from the rotating speed N1 of the roller to the speed 0, and then reversely accelerating to the rotating speed N2;

s708, controlling the motor to rotate, and keeping the rotating speed N2 running for a duration T2;

s710, after the time T2 is up, controlling the motor to pass through at zero speed, decelerating from the rotating speed N2 of the roller to the speed 0, and then accelerating to the rotating speed N1;

in step S712, it is determined whether or not washing is completed, and if the determination result is no, the step S704 is executed.

Fig. 8 shows a schematic block diagram of the rotational speed control of the motor rotor in the present embodiment. The motor zero-speed crossing specifically comprises: the device comprises a speed instruction generation module, a speed controller, a speed arithmetic unit, a current controller, a flux linkage observation unit and a position estimation unit. The speed command generating module is configured to generate a zero-speed crossing speed command, and specifically, fig. 9 shows a speed command schematic diagram of a motor rotor in this embodiment. Speed controller by speed command V_refAnd the feedback speed V_fdbGenerating a torque command T_asr(ii) a Specifically, the speed controller is based on a speed command V_refAnd the feedback speed V_fdbGenerating a velocity error V_errCurrent controller by torque command T_asrAnd feedback current I_fdbGenerating a voltage command U; a flux linkage observation unit for calculating the motor flux linkage according to the voltage and current of the motor; and a position estimation unit for estimating a motor rotor position theta based on the observed flux linkage. Specifically, the motor is controlled to stably operate and a preset rotating speed N1 is controlled, after zero-speed crossing is enabled, the speed instruction generating module generates a speed instruction according to a preset acceleration, the speed instruction is reduced from the rotating speed N1 to 0, the rotating speed of the motor is detected, and when the rotating speed of the motor is lower than a preset threshold value, the speed instruction is stepped to the rotating speed N2, and generation of the zero-speed crossing speed instruction from the rotating speed N1 to the rotating speed N2 is achieved. The speed controller generates a torque instruction through a speed instruction and a feedback speed, the current controller generates a voltage instruction through the torque instruction and the feedback current, the motor is controlled to run according to a zero-speed crossing speed instruction, the speed is reduced from the rotating speed N1 to 0, the rotating speed of the motor is detected, when the rotating speed of the motor is lower than a preset threshold value, the speed instruction is stepped to the rotating speed N2, meanwhile, the preset value given by the current instruction is used as an initial value, a subsequent output current instruction is calculated by the speed controller, and the zero-speed is realizedAnd (4) traversing.

In a second aspect of the present invention, a motor operation control system for a drum washing machine is provided, and fig. 10 shows a schematic block diagram of a motor operation control system 1000 for a drum washing machine according to an embodiment of the present invention. Wherein, the motor operation control system 1000 for the drum washing machine includes: a memory 1002 for storing a computer program; a processor 1004 for executing computer programs to: controlling a rotor of the motor to rotate in an accelerating manner towards a first rotating direction, acquiring the current rotating speed of the motor, and controlling the motor to continuously change from a first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches a first target rotating speed and runs for a first preset time; when the rotating speed of the motor reaches a second target rotating speed and runs for a second preset time, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed, wherein no stop time exists; and the rotating speed direction of the first target rotating speed is opposite to that of the second target rotating speed.

The motor operation control system 1000 for a drum washing machine according to the present invention includes a processor 1004 and a memory 1002, wherein the processor 1004 executes an executable program stored in the memory 1002 to: and after a rotor of the motor is controlled to rotate for a first preset time at a first target rotating speed according to a first rotating direction, the motor is controlled to continuously change the rotating speed from the first target rotating speed to a second target rotating speed. In the process, the stop time in the related art is not reserved, but the motor is controlled to be directly changed from the first target rotating speed to the second target rotating speed with the opposite rotating direction, and the motor is not stopped for a certain time when the rotating speed is zero. Similarly, when the rotating speed of the motor reaches the second target rotating speed and runs for a second preset time period, the motor is controlled to continuously change from the second target rotating speed to the first target rotating speed with the opposite rotating direction, and the motor does not stop rotating for a certain time period when the rotating speed is zero. Therefore, in the reciprocating switching process between the first target speed and the second target speed when the washing machine washes clothes, the stay time at zero speed in the related technology is saved, so that the washing time of the clothes is reduced, the washing efficiency is improved, and the use experience of a user is improved.

In an embodiment of the present invention, preferably, the processor 1004 is further specifically configured to execute a computer program to control the step of continuously changing the motor from the first target rotation speed to the second target rotation speed, specifically including: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range; the processor is further configured to execute a computer program to implement the step of controlling the motor to continuously change from the second target rotation speed to the first target rotation speed, and specifically includes: controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold value, controlling the rotor of the motor to accelerate to a first target rotating speed in a first rotating direction; the second preset threshold is 0, or the second preset threshold is any value of which the difference value with 0 is within a second preset range.

In an embodiment of the present invention, preferably, the processor 1004 is further configured to execute a computer program to implement the step of controlling the rotor of the motor to accelerate to the second target rotation speed in the second rotation direction, specifically including: controlling the rotor to step to a second target rotating speed; and/or the processor is further configured to execute a computer program to implement the step of controlling the rotor of the electric machine to accelerate to the first target rotational speed in the first rotational direction, specifically: and controlling the rotor to step to a first target rotating speed.

In one embodiment of the present invention, the processor 1004 is preferably specifically configured to execute a computer program to: acquiring a driving voltage and a current of a motor; calculating a rotor flux linkage of the motor according to the driving voltage and the current, and calculating a rotor position of the motor according to the rotor flux linkage; and calculating the current rotating speed of the motor according to the rotor position.

In this embodiment, the processor 1004 specifically executes stored computer programs to: the method comprises the steps of calculating the current rotating speed of the motor by obtaining the driving voltage and the current of the motor, specifically, calculating the rotor flux linkage of the current motor by using the driving voltage and the current, calculating the rotor position of the motor by using a flux linkage observation mode, and calculating the current rotating speed of the current rotor by using the calculated rotor position. The current rotating speed can be observed in real time in a flux linkage observation mode, the current rotating speed can be determined only by detecting the driving voltage and sampling the current, the calculation process is simple, and the motor can be controlled conveniently.

In one embodiment of the present invention, the processor 1004 is preferably specifically configured to execute a computer program to: and calculating the back electromotive force of the motor by adopting a voltage model-based stator flux linkage estimation method, performing phase compensation and integral filtering on the back electromotive force, and calculating to obtain the rotor flux linkage.

The processor is specifically used for executing a computer program to calculate back electromotive forces of the motor on α shaft and β shaft based on the stator and the detection α shaft current and β shaft current of the voltage model and the resistance of the motor, perform phase compensation on the calculated back electromotive forces based on the rotation angular frequency of the motor and the filtering frequency to obtain the compensated back electromotive forces on α shaft and β shaft, perform integral filtering on the back electromotive forces to obtain the stator flux linkage of the motor, and calculate the rotor flux linkage of the motor according to a relation formula of the stator flux linkage and the rotor flux linkage to calculate the rotor position of the motor according to the rotor flux linkage so as to determine the current rotation speed of the rotor of the motor and realize the control of the motor.

wherein the phase compensation formula is as follows:

the calculation formula of the integral filtering is as follows:

wherein,

is the flux linkage of the α axis,

is the flux linkage of the β axes, and S is the laplace operator.

In this embodiment, the flux linkage of the α axes

β magnetic linkage of axes

wherein, the rotor flux linkage

And

In this embodiment, the flux linkage of the α axis is obtained by calculation

β magnetic linkage of axes

And

rotor flux linkage obtained by pair calculation

And

In one embodiment of the present invention, the processor 1004 is further preferably configured to execute the computer program to: acquiring a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to the second target rotating speed; the preset speed curve is generated according to a first target rotating speed, a second target rotating speed, a first preset time length and a second target time length; and searching a preset rotating speed corresponding to the current moment in a preset speed curve according to the current moment corresponding to the current rotating speed, and correcting the current rotating speed to be the preset rotating speed when the current rotating speed has deviation from the preset rotating speed.

In one embodiment of the present invention, the processor 1004 is further preferably configured to execute the computer program to: calculating a driving torque according to a difference value between a preset rotating speed and a current rotating speed; and acquiring the current of the motor, calculating a driving voltage according to the current and the driving torque, and controlling the motor to drive the rotor of the motor to rotate by the driving voltage.

In this embodiment, a difference between the preset rotation speed to be acquired and the current rotation speed is calculated, the driving torque is calculated according to the calculated difference, the current of the motor is acquired, the driving voltage for driving the motor to operate is calculated according to the current and the calculated driving torque, and the driving voltage is input to the motor. So that the motor is driven to operate according to the input driving voltage, and further the correction of the preset rotating speed and the current rotating speed is realized. The mode of controlling the motor to correct only needs to obtain the current and does not need to obtain other parameters, so that the data processing process is reduced, the correcting speed is accelerated, the speed reduction time of a motor rotor is reduced, the efficient utilization of the motor is realized, and the washing time of clothes is reduced.

In an embodiment of a third aspect of the present invention, a drum washing machine is provided, and fig. 11 shows a schematic block diagram of a drum washing machine 1100 according to an embodiment of the present invention. Wherein the drum washing machine 1100 includes: a motor operation control system 1102, wherein the motor operation control system 1102 is the motor operation control system 1000 for the drum washing machine.

The drum washing machine 1100 provided by the present invention includes the motor operation control system 1102 according to any of the embodiments, and therefore, the laundry processing device 1100 has all the beneficial technical effects of any of the motor operation control systems 1102, and is not described again.

An embodiment of the fourth aspect of the present invention proposes a computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the motor operation control method according to any one of the above.

The present invention provides a computer-readable storage medium, wherein a computer program is executed by a processor to implement the steps of the motor operation control method according to any of the above embodiments, and therefore the computer-readable storage medium includes all the advantages of the motor operation control method according to any of the above embodiments.

In the description of the present invention, the terms "plurality" or "a plurality" refer to two or more, and unless otherwise specifically limited, the terms "upper", "lower", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are merely for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and thus should not be construed as limiting the present invention; the terms "connected," "mounted," "secured," and the like are to be construed broadly and include, for example, fixed connections, removable connections, or integral connections; may be directly connected or indirectly connected through an intermediate. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the description of the present invention, the description of the terms "one embodiment," "some embodiments," "specific embodiments," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In the present invention, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above is only a preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes will occur to those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A motor operation control method for a drum washing machine is characterized by comprising the following steps:

controlling a rotor of a motor to rotate in an accelerating manner in a first rotating direction, acquiring the current rotating speed of the motor, and controlling the motor to continuously change from a first target rotating speed to a second target rotating speed without stopping time when the rotating speed of the motor reaches the first target rotating speed and runs for a first preset time period;

when the rotating speed of the motor reaches the second target rotating speed and runs for a second preset time, controlling the motor to continuously change from the second target rotating speed to the first target rotating speed, wherein no stop time exists;

wherein the first target rotational speed and the second target rotational speed are opposite in rotational speed direction.

2. The motor operation control method for a drum washing machine according to claim 1, wherein the step of obtaining the current rotation speed of the motor specifically comprises: acquiring a driving voltage and a current of the motor;

calculating a rotor flux linkage of the motor according to the driving voltage and the current, and calculating a rotor position of the motor according to the rotor flux linkage;

and calculating the current rotating speed of the motor according to the rotor position.

3. The motor operation control method for a drum washing machine according to claim 2, wherein the step of calculating the rotor flux linkage of the motor specifically comprises:

and calculating the back electromotive force of the motor by adopting a stator flux linkage estimation method based on a voltage model, performing phase compensation and integral filtering on the back electromotive force, and calculating to obtain the rotor flux linkage of the motor.

4. A motor operation control method for a drum washing machine according to claim 3, wherein the back electromotive force of the motor is calculated by the following formula:

wherein E is_αCounter-potential for the motor α shaft, E_βCounter-potential for the motor β shaft, U_αThe shaft voltage U of the motor α_βIs the motor β shaft voltage, I_αFor the shaft current, I, of the motor α_βIs the motor β shaft current, R is the motor resistance.

5. The motor operation control method for a drum washing machine according to claim 4, wherein the step of performing phase compensation and integral filtering on the back electromotive force is calculated by the following formula:

wherein the phase compensation formula is as follows:

wherein, the E'_αIs the motor α shaft compensated voltage, E'_βCompensated voltage for the motor β axis, E_αCounter-potential for the motor α shaft, E_βIs the motor β shaft back electromotive force, ω_cFor filtering frequency, omega_eIs the motor rotation angular frequency;

the calculation formula of the integral filtering is as follows:

wherein,

is the flux linkage of the α axis,

is the flux linkage of the β axes, and S is the laplace operator.

6. The motor operation control method for a drum washing machine according to claim 4, characterized in that: the rotor flux linkage is calculated by the following formula:

wherein, the rotor flux linkage

And

respectively α axis flux linkage and β axis rotor flux linkage, L_qIs the inductance of the motor rotor, I_αFor the shaft current, I, of the motor α_βIs the motor β shaft current.

7. The motor operation control method for a drum washing machine according to claim 1, wherein the step of controlling the motor to continuously change from the first target rotation speed to the second target rotation speed comprises:

controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a first preset threshold value, controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction; the first preset threshold is 0, or the difference value between the first preset threshold and 0 is any value within a first preset range;

the step of controlling the motor to continuously change from the second target rotation speed to the first target rotation speed specifically includes:

controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to the second preset threshold value, controlling the rotor of the motor to accelerate to the first target rotating speed in the first rotating direction; the second preset threshold is 0, or the second preset threshold is any value of which the difference value with 0 is within a second preset range.

8. The motor operation control method for a drum washing machine according to claim 7,

the step of controlling the rotor of the motor to accelerate to a second target rotating speed in a second rotating direction specifically comprises the following steps: controlling the rotor to step to the second target rotating speed; and/or

The step of controlling the rotor of the motor to accelerate to the first target rotation speed in the first rotation direction specifically includes: and controlling the rotor to step to the first target rotating speed.

9. The motor operation control method for a drum washing machine according to any one of claims 1 to 8, characterized by further comprising:

acquiring a preset speed curve from the acceleration of the motor to the first target rotating speed to the rotation of the motor to a second target rotating speed; the preset speed curve is generated according to the first target rotating speed, the second target rotating speed, the first preset time length and the second target time length;

and searching for a preset rotating speed corresponding to the current moment in the preset speed curve according to the current moment corresponding to the current rotating speed, and correcting the current rotating speed to be the preset rotating speed when the current rotating speed is deviated from the preset rotating speed.

10. The motor operation control method for a drum washing machine according to claim 9, wherein the step of correcting the current rotation speed to the preset rotation speed specifically comprises:

calculating a driving torque according to the difference value between the preset rotating speed and the current rotating speed;

and acquiring the current of the motor, calculating a driving voltage according to the current and the driving torque, and controlling the motor to drive a rotor of the motor to rotate by the driving voltage.

11. A motor operation control system for a drum washing machine, comprising:

a memory for storing a computer program;

a processor for executing the computer program to:

12. A motor operation control system for a drum washing machine according to claim 11, wherein the processor is further configured to execute the computer program to perform the step of controlling the motor to continuously change from the first target speed to a second target speed, specifically comprising:

the processor is further configured to execute the computer program to implement the step of controlling the motor to continuously change from the second target rotation speed to the first target rotation speed, and specifically includes:

controlling the motor to run at a reduced speed, and when the rotating speed of the motor is reduced to a second preset threshold value, controlling the rotor of the motor to accelerate to the first target rotating speed in the first rotating direction; the second preset threshold is 0, or the second preset threshold is any value of which the difference value with 0 is within a second preset range.

13. The motor operation control system of claim 12, wherein the processor is further configured to execute the computer program to perform the step of controlling the rotor of the motor to accelerate to a second target speed in a second rotational direction, specifically comprising:

controlling the rotor to step to the second target rotating speed; and/or

The processor is further configured to execute the computer program to implement the step of controlling the rotor of the motor to accelerate to a first target rotational speed in a first rotational direction, specifically: and controlling the rotor to step to the first target rotating speed.

14. A drum washing machine characterized by comprising: a motor operation control system for a drum washing machine according to any one of claims 11 to 13.

15. A computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the motor operation control method for a drum washing machine according to any one of claims 1 to 10.