Clothes weight detection method of washing machine and related device

Abstract

The invention discloses a clothes weight detection method of a washing machine and a related device. The method comprises the following steps: driving a driving motor of the washing machine to operate at a first speed based on a preset torque current, and obtaining a load torque of the driving motor at the first speed; performing zero clearing operation on the torque current to control the rotating speed of the driving motor to be reduced based on the first speed; in response to the condition that the speed reduction operation of the driving motor reaches a set condition, the speed variation and the time variation of the rotating speed of the driving motor are obtained; wherein the set condition comprises that the falling time from the first speed to the second speed or the rotating speed reaches a preset time threshold value; and obtaining the weight of the clothes in the washing machine based on the load torque, the speed variation and the time variation. The clothes weight detection efficiency and accuracy of the washing machine can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of washing machines, and in particular to a method for detecting the weight of clothes in a washing machine and a related device. Background Art

[0002] As a common household appliance, washing machines are mainly used for washing and dehydrating clothes. In the washing process, the washing machine will determine the appropriate amount of water to be injected according to the actual weight of the clothes, so as to achieve the purpose of energy saving and water saving while ensuring the washing effect. In the dehydration process, the washing machine will also adjust the dehydration acceleration according to the weight of the clothes, so as to take into account the dehydration time and reduce the vibration amplitude. Therefore, before the washing and dehydration processes are started, accurately obtaining the weight information of the clothes is an important prerequisite for the washing machine to achieve efficient and energy-saving operation.

[0003] At present, the two-speed current method and the acceleration inertia method can be used in the relevant technology to obtain the weight information of the clothes. However, both methods need to execute acceleration to the first speed, stabilize at the first speed for a period of time, accelerate to the second speed, and stabilize at the second speed for a period of time, resulting in a long detection time of the clothes weight. Summary of the invention

[0004] The present application provides a method and related device for detecting the weight of clothes in a washing machine, which is beneficial to improving the efficiency and accuracy of detecting the weight of clothes in the washing machine.

[0005] A technical solution adopted in the present application is: to provide a method for detecting the weight of clothes in a washing machine, comprising: driving a driving motor of the washing machine to operate at a first speed based on a preset torque current, and obtaining the load torque of the driving motor at the first speed. Performing a zeroing operation on the torque current to control the speed of the driving motor to decelerate based on the first speed. In response to the deceleration operation of the driving motor reaching a set condition, obtaining the speed change and time change of the speed of the driving motor. Among them, the set condition includes the first speed dropping to the second speed or the speed drop time reaching a preset time threshold. Based on the load torque, speed change and time change, the weight of clothes in the washing machine is obtained.

[0006] In some embodiments, the drive motor of the washing machine is driven to operate at a first speed based on a preset torque current, and the load torque of the drive motor at the first speed is obtained, including: adjusting the torque current based on the first speed so that the electromagnetic torque of the drive motor is equal to the load torque, thereby controlling the speed of the drive motor to operate constantly within a preset time period. Based on the electromagnetic torque of the drive motor being equal to the load torque, the load torque of the drive motor at the first speed is obtained.

[0007] In some embodiments, based on the electromagnetic torque of the drive motor being equal to the load torque, obtaining the load torque of the drive motor at the first speed includes: based on the electromagnetic torque being equal to the load torque, sampling and calculating the average torque current of the torque current in the time period, and converting the average torque current to obtain the load torque of the drive motor at the first speed.

[0008] In some embodiments, sampling and calculating the average torque current of the torque current in the time period includes: calculating the tub cycle of the washing machine based on the first speed, and taking at least one tub cycle as the time period. The torque current in the time period is filtered and collected by a preset current accumulator to obtain the average torque current.

[0009] In some embodiments, based on the first speed, the torque current is adjusted so that the electromagnetic torque of the drive motor is equal to the load torque, including: through the speed loop controller, initiating a torque current reference instruction and a current reference instruction corresponding to the first speed to the current loop controller, so that the current loop controller uses a proportional-integral regulator to decouple the excitation current and torque current fed back by the drive motor, thereby making the electromagnetic torque of the drive motor equal to the load torque.

[0010] In some embodiments, performing a zeroing operation on the torque current includes: setting the torque current and the excitation current to zero by the current loop controller in response to a torque current zeroing request of the speed loop controller.

[0011] In some embodiments, the weight of the laundry in the washing machine is obtained based on the load torque, the speed change and the time change, including: obtaining the total mechanical inertia based on the load torque, the speed change and the time change. The weight of the laundry in the washing machine is obtained based on the total mechanical inertia.

[0012] In some embodiments, the weight of the clothes in the washing machine is obtained according to the total mechanical inertia, including: obtaining a monotonic function relationship between the total mechanical inertia and the clothes weight. The monotonic function relationship is obtained by calibrating a preset clothes weight data set and a preset total mechanical inertia data set. The clothes weight is determined based on the monotonic function relationship.

[0013] In some embodiments, in response to a set condition that the first speed decreases to the second speed, in response to the speed reduction operation of the drive motor reaching the set condition, obtaining the speed change amount and time change amount of the speed of the drive motor includes: in response to the speed starting to decrease based on the first speed, using a time accumulator to record the time when the first speed decreases to the second speed, and obtaining the time change amount. The speed change amount is obtained according to the first speed and the second speed.

[0014] In some embodiments, in response to the set condition that the falling time of the rotational speed reaches a time threshold, in response to the speed reduction operation of the drive motor reaching the set condition, the speed change amount and time change amount of the rotational speed of the drive motor are obtained, including: in response to the falling time of the rotational speed reaching the time threshold, obtaining the second speed when the falling time reaches the time threshold. According to the time threshold, the time change amount is obtained. According to the first speed and the second speed, the speed change amount is obtained.

[0015] Another technical solution adopted by the present application is to provide a washing machine, the washing machine comprising a memory and a processor. The memory is used to store executable program codes. The processor is used to call and run the executable program codes from the memory, so that the washing machine executes any one of the above laundry weight detection methods for the washing machine.

[0016] Another technical solution adopted by the present application is: providing a computer-readable storage medium, the computer-readable storage medium storing a computer program, and when the computer program is executed by a processor, implementing any of the above methods for detecting the weight of clothes in a washing machine.

[0017] The embodiment of the present application provides a method for detecting the weight of clothes in a washing machine, the method comprising: driving a driving motor of the washing machine to operate at a first speed based on a preset torque current, obtaining the load torque of the driving motor at the first speed; performing a zeroing operation on the torque current to control the speed of the driving motor to decelerate based on the first speed; in response to the deceleration operation of the driving motor reaching a set condition, obtaining the speed change and time change of the speed of the driving motor; wherein the set condition includes the first speed dropping to the second speed or the speed drop time reaching a preset time threshold; based on the load torque, speed change and time change, obtaining the weight of clothes in the washing machine. By obtaining the load torque of the driving motor stable at the first speed, and controlling the deceleration of the driving motor by zeroing the torque current, the risk of the acceleration and current impact of the motor on the detection accuracy can be reduced; and in the process of deceleration, the speed change and time change from the first speed to the second speed are obtained, and then the weight of clothes in the washing machine is calculated according to the load torque, speed change and time change. Compared with the steps in the related art, the detection steps in the scheme of the present embodiment are simpler, which is conducive to improving the efficiency and accuracy of the detection of the weight of clothes in the washing machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a flow chart of a first embodiment of a method for detecting the weight of clothes in a washing machine of the present application;

[0019] Figure 2 It is a flow chart of a second embodiment of a method for detecting the weight of clothes in a washing machine of the present application;

[0020] Figure 3It is a schematic diagram of the basic principle of the laundry weight detection method of the washing machine of the present application;

[0021] Figure 4 It is a schematic diagram of the physical device architecture and algorithm framework of the laundry weight detection method of the washing machine of the present application;

[0022] Figure 5 It is a flow chart of a third embodiment of a method for detecting the weight of clothes in a washing machine of the present application;

[0023] Figure 6 It is a schematic diagram of an exemplary process of a method for detecting the weight of clothes of a washing machine of the present application;

[0024] Figure 7 is an exemplary structural block diagram of a washing machine of the present application's laundry weight detection method;

[0025] Figure 8 It is an exemplary structural block diagram of a computer-readable storage medium of the laundry weight detection method of the washing machine of the present application.

[0026] Reference numerals: washing machine 400 , speed loop controller 401 , current loop controller 402 , rotor position observer 403 , drive motor 404 , space voltage vector 405 , Park transformation module 406 , Park inverse transformation module 407 , inverter circuit 408 . DETAILED DESCRIPTION

[0027] The present application is described in detail below with reference to the accompanying drawings and implementation methods.

[0028] See also Figure 1 , Figure 1 1 is a flow chart of the first embodiment of the laundry weight detection method of the washing machine of the present application. It should be noted that if there are substantially the same results, the method of the present application is not limited to the first embodiment. Figure 1 The process sequence shown is limited. Figure 1 As shown, the method includes:

[0029] Step S110 , driving a driving motor of the washing machine to operate at a first speed based on a preset torque current, and acquiring a load torque of the driving motor at the first speed.

[0030] Among them, the torque current can be used to drive the driving motor of the washing machine to reach the first speed to provide a stable driving force, and enable the load torque of the driving motor of the washing machine at the first speed to be accurately measured. The load torque at the first speed can be the torque required for the driving motor to overcome the weight of the clothes and the mechanical resistance at the first speed, which is used to detect the weight of the clothes. The first speed can be the starting speed of the natural deceleration process after the torque current is cleared, and forms a speed change with the second speed, which can also be used to detect the weight of the clothes.

[0031] Step S120 , performing a zeroing operation on the torque current to control the rotation speed of the drive motor to decrease based on the first speed.

[0032] Among them, performing a zeroing operation on the torque current can stop the drive motor from outputting torque, thereby causing the drive motor to decelerate by relying on inertia and external loads.

[0033] Step S130, in response to the deceleration operation of the drive motor reaching a set condition, the speed change and time change of the rotation speed of the drive motor are obtained; wherein the set condition includes the first speed dropping to the second speed or the rotation speed drop time reaching a preset time threshold.

[0034] Among them, since the drive motor relies on inertia and external load to decelerate, that is, the deceleration caused by the free stop method of the drive motor is mainly determined by the weight of the clothes and the mechanical resistance, the speed change can reflect the amplitude of the drive motor deceleration, and the time change can reflect the time required for the drive motor to decelerate. By clearing the torque current, the interference of the artificial driving force can be eliminated, making the measurement result more accurate.

[0035] Step S140, obtaining the weight of the clothes in the washing machine based on the load torque, the speed change and the time change.

[0036] Among them, the load torque can be used as a static parameter to provide information about the initial resistance of the clothes to the drive motor; the speed change and time change can be used as dynamic parameters to provide the dynamic impact of the clothes during the deceleration process. By combining static parameters and dynamic parameters and performing weight calculations, the measured data can be converted into clothing weight values, which can then provide data for subsequent washing processes, such as the water level and dehydration speed of the washing machine.

[0037] This embodiment obtains the load torque of the driving motor when it is stable at the first speed, and controls the speed reduction of the driving motor by clearing the torque current, so as to reduce the risk of motor acceleration and current impact on detection accuracy; and obtains the speed change and time change from the first speed to the second speed during the speed reduction process, and then calculates the weight of the clothes in the washing machine according to the load torque, speed change and time change. Compared with the steps in the related art, the detection steps in the scheme of this embodiment are simpler, which is conducive to improving the efficiency and accuracy of clothing weight detection in the washing machine.

[0038] This embodiment also takes into account that the current calculated by the two-speed current method in the related art is greatly affected by the current sampling fluctuation, and the acceleration inertia method needs to increase the acceleration in order to obtain better weight differentiation, which is easy to cause current shock and affect the reliability of the washing machine drive motor controller. Therefore, this embodiment proposes a washing machine clothing weighing method based on the free stop method. By detecting the average current and the deceleration time at a certain fixed speed, the total mechanical inertia of the load can be calculated, and the weight of the clothing can be inferred.

[0039] See also Figure 2 , Figure 2 1 is a flow chart of a second embodiment of a method for detecting the weight of laundry in a washing machine of the present application. The method may include the following steps:

[0040] Step S210, based on the first speed, adjusting the torque current so that the electromagnetic torque of the drive motor is equal to the load torque, thereby controlling the speed of the drive motor to run constantly within a preset time period.

[0041] As an illustrative example, the working mode of the washing machine can be switched to the dehydration mode or the washing mode, and the driving motor of the washing machine can be driven to reach the set first speed with a preset acceleration slope. At the first speed, the torque current of the driving motor can be adjusted so that the electromagnetic torque of the driving motor is just equal to the load torque and runs for a period of time. During this period of time, the speed of the driving motor remains stable, which is conducive to eliminating the disturbance introduced by the speed change of the driving motor and improving the stability of the load torque measurement.

[0042] Step S220: Based on the electromagnetic torque of the driving motor being equal to the load torque, the load torque of the driving motor at the first speed is obtained.

[0043] As an illustrative example, when the electromagnetic torque is equal to the load torque, the load torque value can be calculated by detecting the average torque current of the drive motor. The load torque can include the combined effects of the inertia torque of the clothes, the inertia torque of the barrel, the friction torque, etc., which is used to distinguish the inertia contribution of the clothes load and the barrel itself. Constant operation is conducive to improving the torque balance, which can be used to reflect the load torque.

[0044] Step S230, performing a zeroing operation on the torque current to control the rotation speed of the drive motor to decrease based on the first speed.

[0045] The above step S120 may be performed and will not be described in detail herein.

[0046] Step S240, in response to the deceleration operation of the drive motor reaching a set condition, the speed change and time change of the rotation speed of the drive motor are obtained; wherein the set condition includes the first speed dropping to the second speed or the rotation speed drop time reaching a preset time threshold.

[0047] As an illustrative example, in response to the rotation speed of the driving motor starting to decrease based on the first speed, a time accumulator is used to record the time it takes for the first speed to drop to the second speed to obtain a time change; and a speed change is obtained based on the first speed and the second speed.

[0048] In some specific implementations, at the moment when the electromagnetic torque is reset to zero, Figure 3 At the moment t1, the time accumulator can be cleared and timing can be started until the speed of the drive motor drops to the preset second speed ω2. Figure 3 At the moment t2, the speed change Δω=ω2-ω1 of the driving motor from the first speed ω1 to the second speed ω2 can be obtained. At the same time, by timing with the time accumulator, the time change Δt (Δt=t2-t1) consumed by the speed ω1 to the second speed ω2 can be obtained.

[0049] As another illustrative example, in response to the falling time of the speed of the driving motor reaching a time threshold, the second speed when the falling time of the speed reaches the time threshold is obtained; the time change is obtained according to the time threshold; the speed change is obtained according to the first speed and the second speed. Among them, the time threshold corresponds to the falling time of the speed of the driving motor, that is, it can be the time interval from the start of the speed reduction to the stop of the speed reduction of the driving motor based on the first speed.

[0050] In some specific implementations, at the moment when the electromagnetic torque is reset to zero, Figure 3 At the moment t1, assuming that the time threshold Δt is known and the speed change Δω is unknown, the time point t2 when the drive motor stops decelerating can be known based on the moment t1 and the time threshold Δt. The time accumulator can be cleared and timing can be started at the moment t1 when the electromagnetic torque is cleared, and the speed of the drive motor starts to decrease based on the first speed ω1. When the timing time reaches the preset time t2, the second speed ω2 when the current drop time of the drive motor speed reaches the time threshold Δt can be recorded. At this time, the time change Δt can be determined based on the time threshold Δt, and the speed change Δω (Δω=ω2-ω1) can be determined based on the first speed ω1 and the second speed ω2.

[0051] Step S250, obtaining the total mechanical inertia based on the load torque, the speed change and the time change;

[0052] As an illustrative example, the total mechanical inertia may include the total inertia of the drive motor rotor, the transmission wheel, the washing tub and the clothes, wherein the inertia of the drive motor rotor, the transmission wheel and the washing tub is fixed. By utilizing the relationship between the speed and time of the tub during free deceleration and combining the load torque, the total mechanical inertia can be calculated according to the motion equation of the drive motor.

[0053] Step S260, obtaining the weight of the clothes in the washing machine according to the total mechanical inertia.

[0054] As an illustrative example, since the total mechanical inertia is a monotonic function of the weight of the clothes, the weight of the clothes can be converted through a pre-calibrated comparison relationship between the total mechanical inertia and the weight of the clothes, based on the fact that the inertia of the clothes is linearly or nonlinearly proportional to its weight.

[0055] In an exemplary embodiment, the working mode of the washing machine can be switched to the dehydration mode or the washing mode, and the motor is driven to reach the set first speed with a predetermined acceleration slope. After the drive motor reaches the first speed, it maintains stable operation for a predetermined period of time, and the torque current signal of the drive motor is low-pass filtered during this period of time to extract the arithmetic mean of the stable signal. At the same time, the set time period is at least greater than one barrel rotation cycle, which can effectively filter out high-frequency noise in the torque current of the drive motor, such as fluctuations caused by barrel eccentricity and vibration. The calculated average torque current is converted into load torque. Then, the torque current is slowly reduced to zero, so that the drive motor enters a free stop state, which is only affected by the mechanical inertia and friction resistance of the system, and can be used to calculate the weight of the clothes. Then, the speed signal of the drive motor is first-order low-pass filtered to filter out noise and extract a smooth deceleration process curve; at the same time, the time when the speed of the drive motor drops from the first speed to the predetermined second speed is recorded, wherein the first speed is greater than the second speed. According to the motion equation of the drive motor, combined with the deceleration time and speed change, the total mechanical inertia of the washing machine barrel is calculated. Finally, based on the pre-calibrated inertia of the drum itself and removing the inertia of the inherent components of the washing machine system, the additional inertia of the clothes can be obtained.

[0056] In this embodiment, the dynamic characteristics of the driving motor of the washing machine are utilized in combination with the deceleration characteristics during the free stop process. By detecting the average current at a certain fixed speed and the deceleration time, the total mechanical inertia of the load can be calculated, and the weight of the clothes can be inferred. Compared with the related art, the detection time is greatly shortened; at the same time, by calculating the average current at a steady speed, the accuracy of the current can be improved, and a relatively large acceleration is not required, which can reduce the risk of current shock.

[0057] See also Figure 4 , Figure 4 It is a physical device architecture diagram and algorithm framework schematic diagram for detecting the weight of clothes in a washing machine according to the present invention. Figure 4The washing machine 400, speed loop controller 401, current loop controller 402, rotor position observer 403, drive motor 404, space voltage vector 405, park transformation module 406 (park transformation), park inverse transformation module 407 (park inverse transformation), inverter circuit 408 are shown. The drive motor 404 includes but is not limited to permanent magnet synchronous drive motor PMSM, brushless DC drive motor BLDC, synchronous reluctance drive motor SynRM and asynchronous drive motor ACIM; the inverter circuit 408 includes but is not limited to insulated gate bipolar transistor inverter circuit (Insulated Gate Bipolar Transistor, IGBT).

[0058] The speed loop controller 401 can be configured to provide a target speed command according to the program, washing program or dehydration program of the washing machine 400. The actual speed ω of the drive motor 404 is adjusted by a proportional integral (PI) regulator. m The output of the speed loop controller 401 is the torque current It serves as an input reference instruction for the subsequent cascade current loop controller 402;

[0059] The current loop controller 402 generates a torque current reference command I according to the output of the speed loop controller 401. q * And the excitation current reference command Generally speaking The feedback current I of the drive motor 404 is controlled by a proportional integral (PI) regulator. q ,I d Decoupling control is performed to output a voltage command U to the drive motor 404. d , U q , the voltage command generates a pulse width modulation wave through the space voltage vector 405 and acts on the inverter circuit 408, thereby acting on the drive motor 404 to make it run to the target speed;

[0060] The rotor position observer 403, according to the voltage (U d , U q ) and current (I q ,I d ) signal as the input of the state observer to realize the rotor position angle (θ) and motor speed (ω) of the drive motor 404 m ) observation, used for speed loop controller 401 and current loop controller 402. The control object includes: drive motor 404, transmission wheel. Among them, the transmission wheel is used to realize the transmission of the washing tub of the washing machine 400 by the drive motor 404, and the washing tub can include but is not limited to the horizontal axis washing tub and the vertical axis washing tub.

[0061] See also Figure 5 , Figure 5 1 is a flow chart of a third embodiment of a method for detecting the weight of laundry in a washing machine of the present application. The method comprises the following steps:

[0062] In step S501, a torque current reference instruction and a current reference instruction corresponding to a first speed are initiated to a current loop controller through a speed loop controller, so that the current loop controller uses a proportional-integral regulator to decouple the excitation current and torque current fed back by the drive motor, thereby making the electromagnetic torque of the drive motor equal to the load torque.

[0063] As an illustrative example, according to the standard drive motor motion equation:

[0064]

[0065] Among them, T e Represents the electromagnetic torque of the driving motor; T L represents the load torque of the drive motor; J represents the moment of inertia of the drive motor; ω m represents the mechanical angular velocity of the drive motor; B represents the damping coefficient; represents a differential operator.

[0066] Since the damping coefficient B of the drive motor can be ignored here, the motion equation of the drive motor can be simplified as follows:

[0067]

[0068] In an exemplary embodiment, by switching the washing machine to the washing mode or the dehydration mode, the driving motor can drive the washing tub to rotate through the transmission belt. At this time, the driving motor is operated to the first speed ω1. The washing program is switched to the dehydration mode in advance, and the washing machine controller controls the driving motor to rotate the washing tub. When the driving motor is operated at the first speed ω1, in order to maintain a constant speed, that is, the speed change rate is zero. At this time, according to the motion equation of the drive motor (Equation 2), the electromagnetic torque of the drive motor is equal to the load torque, that is, T e =T L .

[0069] See also Figure 3 ,like Figure 3 In the time period (t0-t1) shown, the speed loop controller outputs a torque current to ensure that the electromagnetic torque is equal to the load torque, thereby ensuring that the speed of the drive motor is constant at a preset first speed ω1.

[0070] Step S502, based on the electromagnetic torque being equal to the load torque, sampling and calculating the average torque current of the torque current in the time period;

[0071] By sampling and calculating the torque current I in this time period q Average torque current I q avg , you can get the current load torque T of the drive motor L , load moment T L It can include the drive motor rotor, transmission wheel, washing tub and total load of clothing weight.

[0072] In some embodiments, the drum cycle of the washing machine is calculated based on the first speed, and at least one drum cycle is used as a time period; the torque current in the time period is filtered and collected by a preset current accumulator to obtain an average torque current.

[0073] Considering that when the clothes are placed eccentrically, the torque in one barrel cycle presents a sine-like fluctuation, the average value of the signal in a complete cycle can effectively offset the periodic fluctuation and improve the accuracy of the measurement result. Therefore, after the speed reaches the first speed, the time Tr required to run more than one barrel cycle can be calculated to obtain the average torque of one barrel cycle. Therefore, at the beginning of a barrel cycle, the corresponding Figure 3 At t0, the torque current accumulator can be cleared and the filtered torque current can be collected until a complete barrel cycle ends, corresponding to Figure 3 The t1 moment.

[0074] Step S503: convert the average torque current to obtain the load torque of the drive motor at the first speed.

[0075] After the first speed ω1 runs a complete barrel cycle, the average torque current value is obtained, and the average load torque is calculated. The average load torque is stored in the random access memory (RAM) of the digital signal processor (DSP), and the electromagnetic torque is cleared to zero through the speed loop controller, corresponding to Figure 3 At time t1, the washing tub and the driving motor begin to slowly decelerate.

[0076] Step S504 , in response to the torque current clearing request of the speed loop controller, the current loop controller sets the torque current and the excitation current to zero, so as to control the rotation speed of the drive motor to decrease based on the first speed.

[0077] For illustrative examples, see Figure 3 At time t1, the output torque current of the speed loop controller is cleared to zero. At this time, due to the electromagnetic torque T e When the speed is zero, the washing machine drum starts to decelerate freely, and the drive motor is driven to decelerate together through the transmission wheel. At this time, the motion equation of the drive motor becomes as follows (Equation 3):

[0078]

[0079] Among them, the inertia of the total mechanical inertia driving motor rotor, transmission wheel and washing machine drum is fixed, and the difference in dt value mainly comes from the difference caused by the inertia increment brought by the weight of the clothes.

[0080] In an exemplary embodiment, this embodiment is as follows Figure 4 The sensorless vector control method shown in the figure is Figure 3 When the electromagnetic torque is cleared at time t1, the given torque current and excitation current To keep the current controller of the device in operation state, the rotor position observer can be used to observe and detect the motor speed in real time.

[0081] In another exemplary embodiment, this embodiment is a control method with a position sensor. Since there is a physical sensor to sense the speed in real time, Figure 3 Clearing the electromagnetic torque at time t1 can also be achieved by turning off the pulse width modulation (PWM) output.

[0082] Step S505, in response to the deceleration operation of the driving motor reaching a set condition, the speed change and time change of the rotation speed of the driving motor are obtained; wherein the set condition includes the first speed dropping to the second speed or the rotation speed drop time reaching a preset time threshold.

[0083] The implementation of step S505 and the beneficial effects achieved therefrom may be the same as those of steps S130 and / or S240 described above, and will not be described in detail herein.

[0084] Step S506, obtaining the total mechanical inertia based on the load torque, the speed change and the time change;

[0085] As an illustrative example, (Formula 3) can be transformed to obtain (Formula 4):

[0086]

[0087] According to the motion equation of the driving motor, the total mechanical inertia J can be calculated. The total mechanical inertia J can be a monotonic function of the weight of the clothes. Therefore, the final weight of the clothes can be obtained through the pre-calibrated correspondence between the total mechanical inertia and the weight of the clothes, and the clothes weighing can be completed.

[0088] Step S507, obtaining a monotonic function relationship between the total mechanical inertia and the weight of the clothes; wherein the monotonic function relationship is obtained by calibrating a preset clothing weight data set and a preset total mechanical inertia data set;

[0089] As an example, the total inertia of the washing tub system and the weight of the clothes show a certain regularity (linear or nonlinear), and the weight can be indirectly calculated through calibration. After the calibration is completed, the corresponding relationship between the inertia and the weight can be stored in the washing machine in the form of a table, curve fitting, function formula, etc.

[0090] For example, the monotonic function relationship between the total mechanical inertia and the weight of the clothes can be stored in the form of a discrete table; the calibration data can be fitted into a continuous mathematical model (such as a polynomial function, a piecewise linear function, etc.); the calibration relationship can also be accurately modeled and stored as a specific function formula, and real-time calculations can be performed according to the formula.

[0091] Step S508, determining the weight of the clothes based on the monotonic function relationship.

[0092] As an illustrative example, the corresponding relationship between the total mechanical inertia and the weight of the clothes can be obtained through the monotonic function relationship obtained through experimental calibration.

[0093] In an exemplary embodiment, see Figure 6 First, by running the speed of the driving motor to the first speed, the barrel operation cycle Tr of the washing machine barrel is calculated according to the transmission ratio of the washing machine; then, the speed of the driving motor is controlled to run constantly for a period of time based on the first speed; when the running time of the driving motor is less than or equal to the barrel operation cycle Tr, the filtered torque current is collected and accumulated; when the running time of the driving motor is greater than the barrel operation cycle Tr, the average torque current of the torque current is calculated, and the load torque is calculated based on the average torque current; then, the speed loop is cleared to output a torque current clearing request, so that the speed of the driving motor is reduced from the first speed to the second speed, and the speed change is obtained; at the same time, in the process of the speed of the driving motor decreasing from the first speed to the second speed, the time consumed by the speed reduction can be accumulated by timing to obtain the time change; finally, the total mechanical inertia of the washing machine is calculated according to the speed change, the time change and the load torque, and then the weight of the clothes can be calculated according to the monotonic function relationship between the total mechanical inertia and the duty weight.

[0094] In this embodiment, the total mechanical inertia J is estimated through the motion equation based on two changes in the differential operator of the motor motion equation, namely, the speed change Δω and the time change Δt. In addition, before the weighing is performed, the corresponding relationship between the total mechanical inertia J and the weight of the clothes is obtained through an experimental calibration method. When the weighing is finally performed, the weight of the clothes is obtained through the corresponding relationship (which can be a table, a curve or a function), which can reduce the detection complexity and time-consuming cost, and reduce the risk of current shock caused by the acceleration inertia method.

[0095] See also Figure 7 , Figure 7is an exemplary structural block diagram of a washing machine of the present application of the laundry weight detection method of the washing machine. Figure 7 As shown, the washing machine 700 of the present application may include a processor 701 and a memory 702, wherein the processor 701 and the memory 702 communicate with each other via a bus. The memory 702 stores program instructions for detecting the weight of clothes in the washing machine. When the program instructions are executed by the processor 701, the processor executes the above-mentioned related method steps to implement a method for detecting the weight of clothes in the washing machine in the above-mentioned embodiment.

[0096] See also Figure 8 , Figure 8 is an exemplary structural block diagram of a computer-readable storage medium of the laundry weight detection method of the washing machine of the present application. Figure 8 As shown, the computer readable storage medium 800 stores a computer program 801. When the computer program 801 is executed by a processor on a computer, the computer executes the above-mentioned related method steps to implement a method for detecting the weight of clothes of a washing machine in the above-mentioned embodiment.

[0097] In the above scheme, the driving motor of the washing machine is driven to operate at a first speed based on a preset torque current, and the load torque of the driving motor at the first speed is obtained; the torque current is cleared to control the speed of the driving motor to decelerate based on the first speed; in response to the deceleration operation of the driving motor reaching the set condition, the speed change and time change of the speed of the driving motor are obtained; wherein the set condition includes the first speed dropping to the second speed or the speed drop time reaching the preset time threshold; based on the load torque, speed change and time change, the weight of the clothes in the washing machine is obtained. By obtaining the load torque of the driving motor stable at the first speed, and controlling the deceleration of the driving motor by clearing the torque current, the risk of the acceleration and current impact of the motor on the detection accuracy can be reduced; and the speed change and time change from the first speed to the second speed are obtained during the deceleration process, and then the weight of the clothes in the washing machine is calculated according to the load torque, speed change and time change. Compared with the steps in the related art, the detection steps in the scheme of this embodiment are simpler, which is conducive to improving the efficiency and accuracy of the detection of the clothes weight of the washing machine.

[0098] In the several embodiments provided in the present application, it should be understood that the disclosed method, washing machine and storage medium can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of modules or units is only a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0099] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0100] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0101] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application is essentially or the part that contributes to the prior art or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, server, or network device, etc.) or a processor (processor) to perform all or part of the steps of each implementation method of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program code.

[0102] The above are only implementation methods of the present application, and are not intended to limit the patent scope of the present application. Any equivalent structure or equivalent process transformation made using the contents of the present application specification and drawings, or directly or indirectly used in other related technical fields, are also included in the patent protection scope of the present application.

Claims

1. A method for detecting the weight of clothes in a washing machine, characterized in that: The clothing weight detection method comprises: driving a driving motor of the washing machine to operate at a first speed based on a preset torque current, and obtaining a load torque of the driving motor at the first speed; performing a zeroing operation on the torque current to control the rotation speed of the drive motor to decrease based on the first speed; In response to the deceleration operation of the drive motor reaching a set condition, obtaining a speed change amount and a time change amount of the rotation speed of the drive motor; wherein the set condition includes that the first speed drops to the second speed or the decrease time of the rotation speed reaches a preset time threshold; The weight of the laundry in the washing machine is obtained based on the load torque, the speed change and the time change.

2. The method according to claim 1, characterized in that The step of driving the driving motor of the washing machine to operate at a first speed based on a preset torque current, and obtaining the load torque of the driving motor at the first speed includes: Based on the first speed, the torque current is adjusted so that the electromagnetic torque of the drive motor is equal to the load torque, thereby controlling the speed of the drive motor to run constantly within a preset time period; Based on the electromagnetic torque of the drive motor being equal to the load torque, the load torque of the drive motor at the first speed is obtained.

3. The method according to claim 2, characterized in that The obtaining the load torque of the drive motor at the first speed based on the electromagnetic torque of the drive motor being equal to the load torque includes: Based on the electromagnetic torque being equal to the load torque, sampling and calculating an average torque current of the torque current in the time period; The average torque current is converted to obtain the load torque of the drive motor at the first speed.

4. The method according to claim 3, characterized in that The step of sampling and calculating the average torque current of the torque current in the time period includes: calculating a tub cycle of the washing machine based on the first speed, and using at least one of the tub cycles as the time period; The torque current in the time period is filtered and collected by a preset current accumulator to obtain the average torque current.

5. The method according to claim 2, characterized in that: The step of adjusting the torque current based on the first speed so that the electromagnetic torque of the drive motor is equal to the load torque includes: Through the speed loop controller, a torque current reference instruction and a current reference instruction corresponding to the first speed are initiated to the current loop controller, so that the current loop controller uses a proportional-integral regulator to decouple the excitation current and the torque current fed back by the drive motor, thereby making the electromagnetic torque of the drive motor equal to the load torque.

6. The method according to claim 5, characterized in that The performing a zeroing operation on the torque current includes: The current loop controller responds to the torque current clearing request of the speed loop controller to set the torque current and the excitation current to zero.

7. The method according to claim 1, characterized in that The step of obtaining the weight of the laundry in the washing machine based on the load torque, the speed variation and the time variation comprises: Obtaining a total mechanical inertia based on the load torque, the speed change and the time change; The weight of the laundry in the washing machine is obtained according to the total mechanical inertia.

8. The method according to claim 7, characterized in that The step of obtaining the weight of the clothes in the washing machine according to the total mechanical inertia comprises: Obtaining a monotonic function relationship between the total mechanical inertia and the weight of the clothing; wherein the monotonic function relationship is obtained by calibrating a preset clothing weight data set and a preset total mechanical inertia data set; Based on the monotonic functional relationship, the laundry weight is determined.

9. The method according to any one of claims 1 to 8, characterized in that In response to the set condition that the first speed decreases to the second speed, in response to the speed reduction operation of the drive motor reaching the set condition, obtaining the speed change amount and time change amount of the rotation speed of the drive motor includes: In response to the rotation speed starting to decrease based on the first speed, using a time accumulator to record the time from the first speed to the second speed to obtain the time variation; The speed change is obtained according to the first speed and the second speed.

10. The method according to any one of claims 1 to 8, characterized in that In response to the set condition that the falling time of the rotation speed reaches the time threshold, in response to the speed reduction operation of the drive motor reaching the set condition, obtaining the speed change amount and time change amount of the rotation speed of the drive motor includes: In response to the falling time of the rotation speed reaching the time threshold, acquiring a second speed when the falling time of the rotation speed reaches the time threshold; According to the time threshold, obtaining the time variation; The speed change is obtained according to the first speed and the second speed.

11. A washing machine, characterized in that: The washing machine comprises: A memory for storing executable program codes; A processor is used to call and run the executable program code from the memory, so that the washing machine executes the laundry weight detection method of the washing machine as described in any one of claims 1 to 10.

12. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the laundry weight detection method for a washing machine according to any one of claims 1 to 10 is implemented.

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