A dehydration control method for drum washing machine and drum washing machine

Abstract

The present invention provides a dehydration control method for a drum washing machine and a drum washing machine, belonging to the technical field of clothing processing; the drum washing machine comprises a drum and a driving motor; the drum washing machine is provided with a dehydration program, and the dehydration program comprises a speed reduction stage; when the drum washing machine is running in the speed reduction stage, the dehydration control method comprises: obtaining a bus voltage of the driving motor, calculating a change value of the bus voltage per unit time, and controlling the speed reduction of the driving motor according to the change value of the bus voltage; wherein when the speed of the driving motor changes, the bus voltage of the driving motor also changes; the control accuracy of the drum speed reduction process is improved, the electromagnetic noise of the driving motor is reduced, the driving motor is avoided from being in an abnormal state, the driving motor is ensured to operate reliably, the user experience is improved, and the problem that the motor driving the drum is prone to electromagnetic noise and an abnormal state due to unreasonable speed reduction control in the dehydration process of the existing drum washing machine is solved.

Description

Technical Field

[0001] The present invention belongs to the technical field of clothing processing, and in particular relates to a dehydration control method of a drum washing machine and the drum washing machine. Background Art

[0002] At present, as people enter a fast-paced life, users' demand for high-efficiency washing machines is also growing. Drum washing machines are accepted by the public because they can wash a wide variety of clothes; the degree of automation of drum washing machines is getting higher and higher, and the public's requirements for their dehydration are gradually increasing. During the dehydration process, the drum washing machine will produce electromagnetic noise and abnormal conditions when the speed is reduced, which greatly affects the user experience. Summary of the invention

[0003] In view of this, the present invention provides a dehydration control method for a drum washing machine and a drum washing machine to solve the problems of unreasonable speed reduction control during the dehydration process of the existing drum washing machine, which causes the motor driving the drum to rotate to easily generate electromagnetic noise and abnormal conditions.

[0004] The present invention provides a dehydration control method for a drum washing machine, the drum washing machine comprising a drum and a driving motor driving the drum to rotate; the drum washing machine is provided with a dehydration program, the dehydration program comprises a deceleration stage, the deceleration stage comprises n unit durations sequentially and continuously arranged in chronological order; when the drum washing machine runs the deceleration stage, the dehydration control method comprises:

[0005] Obtaining the bus voltage of the drive motor;

[0006] Calculate the current bus voltage change per unit time ΔU i And the change value of bus voltage per unit time ΔU i-1 The difference ΔU'=ΔU i -ΔU i-1 ;

[0007] Determining whether the ΔU' is within a preset bus voltage interval;

[0008] Determining a first speed reduction strategy according to a judgment result of whether ΔU' is within a preset bus voltage interval;

[0009] Controlling the drive motor to operate according to the first speed reduction strategy until the bus voltage reaches a maximum value;

[0010] Wherein, n and i are both positive integers, 2≤i≤n; the ΔU i It is the bus voltage at the end of the previous unit time minus the bus voltage at the end of the current unit time; when the speed of the drive motor changes, the bus voltage of the drive motor also changes.

[0011] Further optionally, the determining the first speed reduction strategy according to the judgment result of whether ΔU' is within a preset bus voltage interval includes:

[0012] When ΔU' is within the preset bus voltage interval, determining that the first speed reduction strategy is to maintain the current speed reduction acceleration per unit time;

[0013] When the ΔU′ is greater than the maximum threshold of the preset bus voltage interval, it is determined that the first speed reduction strategy is to adjust the speed reduction acceleration to the speed reduction acceleration of the previous unit time length.

[0014] Further optionally, the dehydration control method further comprises:

[0015] After the maximum deceleration time has expired, determining whether the drive motor has completed deceleration;

[0016] If the driving motor has not completed deceleration, obtaining the current speed of the driving motor;

[0017] Determining a second speed reduction strategy according to the current speed;

[0018] Controlling the drive motor to operate according to the second speed reduction strategy until the drive motor completes speed reduction;

[0019] The maximum speed reduction duration is related to both the maximum change value and the preset change rate of the bus voltage, and the maximum change value of the bus voltage is related to both the maximum value of the bus voltage and the initial value of the bus voltage.

[0020] Further optionally, determining the second speed reduction strategy according to the current speed includes:

[0021] comparing the current speed with a preset speed;

[0022] When the current speed is greater than the preset speed, determining the second speed reduction strategy to maintain the speed reduction acceleration corresponding to the maximum value of the bus voltage;

[0023] When the current speed is less than or equal to the preset speed, determining the change of the state of the clothes in the drum before and after the driving motor is decelerated; and determining the second deceleration strategy according to the change of the state of the clothes;

[0024] The change in the state of the clothes includes the change in the weight of the clothes in the drum before and after the driving motor slows down and the change in the eccentricity value of the clothes.

[0025] Further optionally, determining the second speed reduction strategy according to the change of the clothing state includes:

[0026] Calculating the change in weight of the clothes in the drum before and after the driving motor is decelerated and the change in eccentricity of the clothes in the drum before and after the driving motor is decelerated;

[0027] Respectively judging whether the change value of the weight of the clothes in the drum is within a preset weight range and whether the change value of the eccentricity value of the clothes in the drum is within a preset eccentricity value range;

[0028] When the change value of the weight of the clothes in the drum is within a preset weight range and the change value of the eccentricity value of the clothes in the drum is within a preset eccentricity value range, determining that the second speed reduction strategy is to control the drum washing machine to end the dehydration program;

[0029] When the change value of the weight of the clothes in the drum is not within the preset weight range or the change value of the eccentricity value of the clothes in the drum is not within the preset eccentricity value range, determining that the second speed reduction strategy is to control the driving motor to first increase the speed and then decrease the speed;

[0030] The change in the weight of the laundry in the drum before and after the driving motor is decelerated is the weight of the laundry in the drum after the constant speed stage and before the deceleration stage of the dehydration program of the drum washing machine, minus the weight of the laundry in the drum after the duration of the deceleration stage of the dehydration program of the drum washing machine reaches the maximum deceleration duration;

[0031] The change in the eccentricity value of the clothes in the drum before and after the driving motor decelerates is the eccentricity value of the clothes in the drum after the constant speed stage and before the deceleration stage of the dehydration program of the drum washing machine, minus the eccentricity value of the clothes in the drum after the duration of the deceleration stage of the dehydration program of the drum washing machine reaches the maximum deceleration duration.

[0032] Further optionally, controlling the driving motor to first increase the speed and then decrease the speed includes:

[0033] Controlling the driving motor to increase the speed to the preset speed, and after maintaining the preset speed for a preset time, controlling the driving motor to decrease the speed;

[0034] The deceleration acceleration of the driving motor is the deceleration acceleration of the previous unit time.

[0035] Further optionally, controlling the driving motor to first increase the speed and then decrease the speed further includes:

[0036] Calculate the change value ΔU of the bus voltage per unit time j ;

[0037] Calculate the current bus voltage change per unit time ΔU j And the change value of bus voltage per unit time ΔU j-1 The difference ΔU"=ΔUj -ΔU j-1 ;

[0038] Determine whether the ΔU" is within a preset bus voltage range;

[0039] When ΔU" is within a preset bus voltage interval, controlling the drum washing machine to end the dehydration procedure;

[0040] When ΔU" is not within the preset bus voltage interval, the drive motor is controlled to keep decelerating until the deceleration time of the drive motor reaches the maximum deceleration time, and the drive motor is controlled to enter a fault judgment mode.

[0041] Further optionally, controlling the drive motor to enter a fault determination mode includes:

[0042] Controlling the driving motor to stop running;

[0043] Acquire current power supply parameters of the power supply of the drive motor;

[0044] Determining whether the current power supply parameter is within a preset power supply parameter range;

[0045] Determining whether the drive motor is faulty according to a result of determining whether the current power supply parameter is within a preset power supply parameter range;

[0046] The current power supply parameters of the power supply of the driving motor at least include a current power supply voltage and a current power supply frequency.

[0047] Further optionally, the determining whether the drive motor is faulty according to a judgment result of whether the current power supply parameter is within a preset power supply parameter interval includes:

[0048] When the current power supply voltage is within the preset power supply voltage range and the current power supply frequency is within the preset power supply frequency range, determining that the drive motor is faulty;

[0049] When the current power supply voltage is not within the preset power supply voltage range and the current power supply frequency is not within the preset power supply frequency range, it is determined that the drive motor has no fault.

[0050] Further optionally, when it is determined that the drive motor has no fault, controlling the drive motor to first increase the speed and then decrease the speed further includes:

[0051] The current power supply voltage and the current power supply frequency are adjusted so that the deceleration acceleration of the drive motor is the preset deceleration acceleration.

[0052] Further optionally, the next time the drum washing machine runs the dehydration program, the dehydration control method further includes:

[0053] The power supply parameters of the power supply of the driving motor are adjusted so that the power supply parameters of the power supply of the driving motor next time are the same as the power supply parameters of the power supply of the driving motor this time.

[0054] The present invention further provides a drum washing machine, wherein the drum washing machine adopts any one of the above described methods for controlling the dehydration of the drum washing machine;

[0055] The drum washing machine comprises a drum and a driving motor, clothes can be placed in the drum, and the driving motor can drive the drum to rotate.

[0056] Compared with the prior art, the beneficial effects of the present invention are mainly:

[0057] When the drum washing machine is running at the deceleration stage, calculate the change value of the bus voltage per unit time ΔU i And the change value of bus voltage per unit time ΔU i-1 The difference ΔU' is determined, and whether ΔU' is in a preset bus voltage interval. According to the judgment result of whether ΔU' is in the preset bus voltage interval, a first speed reduction strategy is determined, and the drive motor is controlled to operate according to the first speed reduction strategy until the bus voltage reaches a maximum value. This improves the control accuracy of the drum speed reduction process, reduces the electromagnetic noise of the drive motor, avoids the abnormal state of the drive motor, ensures the reliable operation of the drive motor, improves the user experience, and solves the problem that the motor driving the drum is prone to electromagnetic noise and abnormal state due to unreasonable speed reduction control during the dehydration process of the existing drum washing machine. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the implementation methods or the description of the prior art. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0059] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

[0060] Figure 1 A schematic flow chart of an embodiment of a dehydration control method for a drum washing machine provided by the present invention; DETAILED DESCRIPTION

[0061] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] The terms used in the embodiments of the present invention are only for the purpose of describing specific embodiments, and are not intended to limit the present invention. The singular forms "a", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two, but does not exclude the inclusion of at least one.

[0063] It should be understood that the term "and / or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0064] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a product or system including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such a product or system. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the product or system including the elements.

[0065] In existing drum washing machines, factors that affect the reliable operation of the motor are not fully considered. The motor has low control accuracy and is prone to electromagnetic noise and abnormal conditions during the dehydration and speed reduction phase, which greatly affects the user experience.

[0066] The present invention creatively provides a dehydration control method for a drum washing machine. When the drum washing machine is running in the deceleration stage, the change value of the bus voltage per unit time is calculated, and the driving motor is controlled to decelerate according to the change value of the bus voltage.

[0067] The control accuracy of the drum deceleration process is improved, the electromagnetic noise of the drive motor is reduced, the drive motor is avoided from abnormal state, the drive motor is ensured to operate reliably, and the user experience is improved.

[0068] Example 1

[0069] like Figure 1As shown, the present embodiment provides a dehydration control method for a drum washing machine, the drum washing machine comprises a drum and a driving motor for driving the drum to rotate; the drum washing machine is provided with a dehydration program, the dehydration program comprises a speed-up stage, a constant speed stage and a speed-down stage; when the drum washing machine is in the speed-up stage, the rotation speed of the drum gradually increases toward a preset dehydration rotation speed, and the clothes in the drum move against the inner wall of the drum under the centrifugal action; when the drum washing machine is in the constant speed stage, the rotation speed of the drum reaches a preset dehydration rotation speed and the drum keeps rotating at the preset dehydration rotation speed, the state of the clothes in the drum reaches stability and rotates with the drum, and the clothes in the drum are mainly dehydrated in the constant speed stage; when the drum washing machine is in the speed-down stage, the rotation speed of the drum gradually decreases from the preset dehydration rotation speed, and the clothes in the drum fall to the bottom wall of the drum under the action of gravity; wherein the preset dehydration rotation speed is determined according to the weight of the clothes in the drum; in the speed-up stage and the speed-down stage, the rotation speed of the drum changes, or when the clothes are heavy or the clothes are eccentric, the driving motor is prone to noise, thereby reducing the user experience;

[0070] This embodiment proposes that when the drum washing machine is in the deceleration stage, the dehydration control method includes:

[0071] S1, obtaining the bus voltage of the drive motor;

[0072] S2. Calculate the change value of bus voltage per unit time;

[0073] S3, controlling the speed of the drive motor to decrease according to the change in bus voltage;

[0074] The unit time length can be defined according to actual conditions. Preferably, the unit time length is 1 second.

[0075] When the speed of the drive motor changes, the bus voltage of the drive motor also changes. The speed reduction acceleration of the drive motor is related to the change value of the bus voltage. According to the change value of the bus voltage of the drive motor, the speed reduction process of the drive motor can be judged; the bus voltage of the drive motor is obtained in real time, and the change value of the bus voltage per unit time is calculated. According to the change value of the bus voltage, the speed reduction of the drive motor can be accurately controlled, and then the speed reduction stage of the drum washing machine can be accurately controlled.

[0076] Example 2

[0077] Based on Example 1, the deceleration stage includes n unit durations arranged sequentially and continuously in chronological order, where n is a positive integer; S3 includes:

[0078] S31, calculate the change value ΔU of the bus voltage per unit time i And the change value of bus voltage per unit time ΔU i-1 The difference ΔU'=ΔU i -ΔU i-1 ;

[0079] S32, determining whether ΔU' is within a preset bus voltage range;

[0080] S33, determining a first speed reduction strategy according to a judgment result of whether ΔU' is within a preset bus voltage interval;

[0081] S34, controlling the drive motor to operate according to the first speed reduction strategy until the bus voltage reaches a maximum value;

[0082] Where i is a positive integer, 2≤i≤n; ΔU i It is the bus voltage at the end of the previous unit time minus the bus voltage at the end of the current unit time; specifically, the bus voltage at the end of the previous unit time is U1, and the bus voltage at the end of the current unit time is U2, then the difference ΔU' between the change value ΔU2 of the bus voltage in the current unit time and the change value ΔU1 of the bus voltage in the previous unit time is U2-U1; and so on, the bus voltage at the end of the next unit time is U3, then the difference ΔU' between the bus voltage at the end of the next unit time and the bus voltage at the end of the current unit time is U2 is U3-U2;

[0083] The bus voltage has a maximum value. Taking the maximum value of the bus voltage as the main parameter for controlling the drive motor can accurately control the speed reduction process of the drive motor and make the drive motor run reliably.

[0084] The specific process of step S33 is further described below. S33 includes:

[0085] When ΔU' is in the preset bus voltage interval, the first speed reduction strategy is determined to maintain the current speed reduction acceleration per unit time; that is, if the change value of the bus voltage per unit time is close to or equal, the drive motor maintains the current speed reduction acceleration to reduce speed;

[0086] When ΔU' is greater than the maximum threshold of the preset bus voltage interval, the first deceleration strategy is determined to adjust the deceleration acceleration to the deceleration acceleration of the previous unit time length; that is, when the change values ​​of the bus voltages of two adjacent unit time lengths are not equal or differ greatly, the current deceleration acceleration is adjusted to the deceleration acceleration of the previous unit time length, so that the deceleration accelerations of the two unit time lengths are equal or close.

[0087] The driving motor operates according to the first deceleration strategy. When the speed of the driving motor reaches zero before the deceleration time reaches the maximum deceleration time, the deceleration of the driving motor ends; when the speed of the driving motor still does not reach zero after the deceleration time reaches the maximum deceleration time, the deceleration strategy of the driving motor needs to be adjusted; therefore, this embodiment proposes that the dehydration control method further includes:

[0088] S4, after the maximum deceleration time ends, determining whether the drive motor has completed deceleration;

[0089] S5. If the driving motor has not completed deceleration, obtain the current speed of the driving motor;

[0090] S6. Determine a second speed reduction strategy according to the current speed;

[0091] S7, controlling the drive motor to operate according to the second speed reduction strategy until the drive motor completes the speed reduction;

[0092] Among them, the maximum speed reduction time is related to the maximum change value and the preset change rate of the bus voltage, and the maximum change value of the bus voltage is related to the maximum value of the bus voltage and the initial value of the bus voltage; specifically, the maximum speed reduction time is equal to the maximum change value of the bus voltage divided by the preset change rate, the maximum change value of the bus voltage is equal to the maximum value of the bus voltage minus the initial value of the bus voltage, and the initial value of the bus voltage is the bus voltage corresponding to the speed of the drive motor when the speed is the initial value of the speed.

[0093] The specific process of step S6 is further described below. S6 includes:

[0094] S61, comparing the current speed with the preset speed;

[0095] S62, when the current speed is greater than the preset speed, determining the second speed reduction strategy to be a speed reduction acceleration corresponding to maintaining the maximum value of the bus voltage;

[0096] S63, when the current speed is less than or equal to the preset speed, determining the change of the state of the clothes in the drum before and after the driving motor is decelerated; and determining a second deceleration strategy according to the change of the state of the clothes;

[0097] Among them, the preset speed is 400r / min, and the change of the clothing state includes the change of the weight of the clothing in the drum before and after the driving motor slows down and the change of the eccentricity value of the clothing.

[0098] Further, determining the second deceleration strategy according to the change of the clothing state in S63 includes:

[0099] S631, calculating the change in weight of the clothes in the drum before and after the driving motor is decelerated and the change in eccentricity of the clothes in the drum before and after the driving motor is decelerated;

[0100] S632, respectively determining whether the change value of the weight of the clothes in the drum is within a preset weight range and whether the change value of the eccentricity value of the clothes in the drum is within a preset eccentricity value range;

[0101] S633, when the change value of the weight of the clothes in the drum before and after the driving motor is decelerated is within the preset weight range and the change value of the eccentricity value of the clothes in the drum before and after the driving motor is decelerated is within the preset eccentricity value range, determining that the second deceleration strategy is to control the drum washing machine to end the dehydration program and complete the dehydration;

[0102] S634, when the change value of the weight of the clothes in the drum before and after the driving motor is decelerated is not within the preset weight range or the change value of the eccentricity value of the clothes in the drum before and after the driving motor is decelerated is not within the preset eccentricity value range, determining the second deceleration strategy to control the driving motor to first increase the speed and then decrease the speed;

[0103] The change in the weight of the laundry in the drum before and after the speed reduction of the driving motor is the weight of the laundry in the drum after the constant speed stage and before the speed reduction stage of the dehydration program of the drum washing machine, minus the weight of the laundry in the drum after the duration of the speed reduction stage of the dehydration program of the drum washing machine reaches the maximum speed reduction duration;

[0104] The change in the eccentricity value of the clothes in the drum before and after the driving motor slows down is the eccentricity value of the clothes in the drum after the constant speed stage and before the speed reduction stage of the dehydration program of the drum washing machine, minus the eccentricity value of the clothes in the drum after the duration of the speed reduction stage of the dehydration program of the drum washing machine reaches the maximum speed reduction duration.

[0105] The driving motor is controlled to increase speed first, so that the clothes in the drum are restored to a new state, and then the driving motor is controlled to decrease speed, so as to reduce the electromagnetic noise of the driving motor. The following further describes this process; S633

[0106] Controlling the drive motor to first increase the speed and then decrease the speed includes:

[0107] S6331, controlling the driving motor to increase the speed to a preset speed, and after maintaining the preset speed for a preset time, controlling the driving motor to decrease the speed;

[0108] Among them, the deceleration acceleration of the drive motor is the deceleration acceleration of the previous unit time, and the preset time is 10 seconds.

[0109] Further, controlling the driving motor to first increase the speed and then decrease the speed in S633 also includes:

[0110] S6332, calculate the change value ΔU of the bus voltage per unit time j ;

[0111] S6333, calculate the current bus voltage change value per unit time ΔU j And the change value of bus voltage per unit time ΔU j-1 The difference ΔU"=ΔU j -ΔU j-1 ;

[0112] S6334, determine whether ΔU" is within the preset bus voltage range;

[0113] S6335, when ΔU" is within the preset bus voltage range, control the drum washing machine to end the dehydration program and complete the dehydration;

[0114] S6336: When ΔU" is not within the preset bus voltage range, the drive motor is controlled to keep decelerating until the deceleration time of the drive motor reaches the maximum deceleration time, and the drive motor is controlled to enter a fault judgment mode.

[0115] After the drive motor enters the fault judgment mode, it may be because of the drive motor failure, or it may be because the power supply parameters of the drive motor power supply are not appropriate, resulting in the inability to complete the speed reduction within the maximum speed reduction time; the fault judgment mode is further described below;

[0116] Controlling the drive motor to enter the fault judgment mode includes:

[0117] S6337, control the drive motor to stop running;

[0118] S6338, obtaining current power supply parameters of the power supply of the drive motor;

[0119] S6339, determining whether the current power supply parameter is within a preset power supply parameter range;

[0120] S63310, determining whether the drive motor is faulty based on a determination result of whether the current power supply parameter is within a preset power supply parameter range;

[0121] The current power supply parameters of the power source driving the motor at least include the current power supply voltage and the current power supply frequency.

[0122] Furthermore, S63310 includes:

[0123] When the current power supply voltage is within the preset power supply voltage range and the current power supply frequency is within the preset power supply frequency range, it is determined that the drive motor is faulty;

[0124] When the current power supply voltage is not within the preset power supply voltage range and the current power supply frequency is not within the preset power supply frequency range, it is determined that the drive motor has no fault.

[0125] When it is determined that the drive motor has no fault, controlling the drive motor to first increase the speed and then decrease the speed further includes:

[0126] The current power supply voltage and the current power supply frequency are adjusted so that the deceleration acceleration of the drive motor is the preset deceleration acceleration, so that the operation of the drive motor meets the current power supply parameters of the power supply.

[0127] When the drum washing machine runs a dehydration program next time, the dehydration control method further includes:

[0128] S8, adjusting the power supply parameters of the power supply for driving the motor so that the power supply parameters of the power supply for driving the motor next time are the same as the power supply parameters of the power supply for driving the motor this time.

[0129] To sum up, the dehydration control method in this embodiment improves the control accuracy of the drum deceleration process, can make the drive motor decelerate quickly under low noise conditions, improves the safety during the deceleration process, ensures the reliable operation of the drive motor, and solves the problem that the motor driving the drum is prone to electromagnetic noise and abnormal conditions due to unreasonable deceleration control during the dehydration process of existing drum washing machines.

[0130] Example 3

[0131] Different from Embodiments 1 and 2, this embodiment provides a dehydration control method for a drum washing machine, comprising:

[0132] During the deceleration process, the change of the bus voltage of the driving motor is detected, and the change range of the bus voltage is set during the process;

[0133] Among them, since the change of bus voltage is related to the deceleration acceleration, and the bus voltage itself has a maximum value, it is used as the protection value of the drive controller; the maximum value of the bus voltage minus the initial value of the bus voltage when the deceleration starts, the difference K between the two is calculated; at the same time, during the deceleration process, the change value F of the bus voltage within 1 second is calculated, and the ratio of K / F is calculated, the result is C, and this ratio is used as the maximum deceleration time during the deceleration;

[0134] If the bus voltage change value F calculated within the maximum deceleration time or every 1 second during the deceleration is the same, the deceleration acceleration is maintained until the bus voltage reaches the maximum value; wherein, the bus voltage change value F within 1 second is calculated by subtracting the bus voltage F1 of the previous second from the bus voltage F2 after 1 second of deceleration, and recursively, the latest bus voltage F2 minus the bus voltage F3 after another 1 second of deceleration, and so on, until the latest bus voltage Fn is the maximum value of the bus voltage;

[0135] If the bus voltage change value F in each second is different from its adjacent change value F during the maximum deceleration time, the deceleration acceleration is reduced to make the changes in the two stages the same;

[0136] If the speed reduction process is not completed within the maximum speed reduction time, different speed reduction controls are performed according to the current speed stage;

[0137] If the current speed is greater than 400 rpm, the current bus voltage maximum value will continue to be maintained to reduce the speed;

[0138] If the current speed is less than or equal to 400 rpm, the deceleration process is adjusted to a brake command to quickly shut down the motor;

[0139] If the above-mentioned speed reduction is not completed or the speed is less than or equal to 400 rpm during the speed reduction process, it is necessary to detect the current state of the clothes again and compare the changes in the weight and eccentricity of the clothes before the speed reduction.

[0140] If there is no difference, dehydration is terminated;

[0141] If there is a difference, the dehydration speed is increased again;

[0142] The target speed for speed increase is 400 rpm. After maintaining this speed for more than 10 seconds, the speed is reduced. The speed reduction acceleration is consistent with the speed reduction acceleration of the last dehydration. The change value of the bus voltage during the speed reduction process is compared with the difference between the change value of the bus voltage during the last dehydration.

[0143] If there is no difference, dehydration is terminated;

[0144] If there is a difference, and the deceleration is not completed within the maximum deceleration time, the fault mode is entered;

[0145] In the fault handling mode, after the speed is reduced to zero, the current supply voltage and current supply frequency of the power supply of the drive motor are calculated;

[0146] Comparing the current power supply voltage of the power supply of the drive motor with the preset power supply voltage and the current power supply frequency of the power supply of the drive motor with the preset power supply frequency, the current power supply voltage is equal to the preset power supply voltage and the current power supply frequency is equal to the preset power supply frequency, and determining that the drive motor or its frequency converter has a fault;

[0147] If the current power supply voltage is not equal to the preset power supply voltage or the current power supply frequency is not equal to the preset power supply frequency, the control parameters of the motor are adjusted within the maximum range of the power supply requirement so that the deceleration acceleration of the drive motor is the preset deceleration acceleration;

[0148] The next time the drum washing machine is dehydrated, the power supply parameters of the current power supply are compared with the power supply parameters of the previous power supply; if they are the same, the current power supply parameters are maintained; if they are different, the power supply parameters are adjusted accordingly or abnormal processing is performed; the power supply parameters include power supply voltage and power supply frequency;

[0149] Through the dehydration control method of the present application, the driving motor can be quickly decelerated with low noise, thereby improving the safety during the deceleration process.

[0150] Example 4

[0151] This embodiment provides a drum washing machine, which adopts the dehydration control method of the drum washing machine described in any one of Embodiments 1 and 2;

[0152] The drum washing machine includes a drum and a driving motor, in which clothes can be placed, and the driving motor can drive the drum to rotate; the drum washing machine is provided with a dehydration program, which includes a speed-up stage, a constant speed stage and a speed-down stage; when the drum washing machine is in the speed-up stage, the rotation speed of the drum gradually increases, and the clothes in the drum move along the inner wall of the drum under the action of centrifuge; when the drum washing machine is in the constant speed stage, the rotation speed of the drum reaches a preset dehydration speed, the state of the clothes in the drum becomes stable and rotates with the drum, and the clothes in the drum are mainly dehydrated in the constant speed stage; when the drum washing machine is in the speed-down stage, the rotation speed of the drum gradually decreases, and the clothes in the drum fall to the bottom wall of the drum under the action of gravity.

[0153] The exemplary embodiments of the present disclosure are specifically shown and described above. It should be understood that the present disclosure is not limited to the detailed structures, configurations or implementations described herein; on the contrary, the present disclosure is intended to cover various modifications and equivalent configurations included in the spirit and scope of the appended claims.

Claims

1. A dehydration control method for a drum washing machine, the drum washing machine comprising a drum and a driving motor for driving the drum to rotate; characterized in that: The drum washing machine is provided with a dehydration program, the dehydration program includes a deceleration phase, and the deceleration phase includes n unit durations arranged sequentially and continuously in chronological order; When the drum washing machine is running in the deceleration stage, the dehydration control method includes: Obtaining the bus voltage of the drive motor; Calculate the current bus voltage change per unit time ΔU i And the change value of bus voltage per unit time ΔU i-1 The difference ΔU'=ΔU i -ΔU i-1 ; Determining whether the ΔU' is within a preset bus voltage interval; Determining a first speed reduction strategy according to a judgment result of whether ΔU' is within a preset bus voltage interval; Controlling the drive motor to operate according to the first speed reduction strategy until the bus voltage reaches a maximum value; Wherein, n and i are both positive integers, 2≤i≤n; the ΔU i It is the bus voltage at the end of the previous unit time minus the bus voltage at the end of the current unit time; when the speed of the drive motor changes, the bus voltage of the drive motor also changes.

2. The dehydration control method of a drum washing machine according to claim 1, characterized in that: The determining of the first speed reduction strategy according to the judgment result of whether ΔU' is within the preset bus voltage interval includes: When ΔU' is within the preset bus voltage interval, determining that the first speed reduction strategy is to maintain the current speed reduction acceleration per unit time; When the ΔU′ is greater than the maximum threshold of the preset bus voltage interval, it is determined that the first speed reduction strategy is to adjust the speed reduction acceleration to the speed reduction acceleration of the previous unit time length.

3. The dehydration control method of a drum washing machine according to claim 2, characterized in that: The dehydration control method further comprises: After the maximum deceleration time has expired, determining whether the drive motor has completed deceleration; If the driving motor has not completed deceleration, obtaining the current speed of the driving motor; Determining a second speed reduction strategy according to the current speed; Controlling the drive motor to operate according to the second speed reduction strategy until the drive motor completes speed reduction; The maximum speed reduction duration is related to both the maximum change value and the preset change rate of the bus voltage, and the maximum change value of the bus voltage is related to both the maximum value of the bus voltage and the initial value of the bus voltage.

4. The dehydration control method of a drum washing machine according to claim 3, characterized in that: Determining the second speed reduction strategy according to the current speed includes: comparing the current speed with a preset speed; When the current speed is greater than the preset speed, determining the second speed reduction strategy to maintain the speed reduction acceleration corresponding to the maximum value of the bus voltage; When the current speed is less than or equal to the preset speed, determining the change of the state of the clothes in the drum before and after the driving motor is decelerated; and determining the second deceleration strategy according to the change of the state of the clothes; The change in the state of the clothes includes the change in the weight of the clothes in the drum before and after the driving motor slows down and the change in the eccentricity value of the clothes.

5. The dehydration control method of a drum washing machine according to claim 4, characterized in that: The determining the second speed reduction strategy according to the change of the clothing state comprises: Calculating the change in weight of the clothes in the drum before and after the driving motor is decelerated and the change in eccentricity of the clothes in the drum before and after the driving motor is decelerated; Respectively judging whether the change value of the weight of the clothes in the drum is within a preset weight range and whether the change value of the eccentricity value of the clothes in the drum is within a preset eccentricity value range; When the change value of the weight of the clothes in the drum is within a preset weight range and the change value of the eccentricity value of the clothes in the drum is within a preset eccentricity value range, determining that the second speed reduction strategy is to control the drum washing machine to end the dehydration program; When the change value of the weight of the clothes in the drum is not within the preset weight range or the change value of the eccentricity value of the clothes in the drum is not within the preset eccentricity value range, determining that the second speed reduction strategy is to control the driving motor to first increase the speed and then decrease the speed; The change in the weight of the laundry in the drum before and after the driving motor is decelerated is the weight of the laundry in the drum after the constant speed stage and before the deceleration stage of the dehydration program of the drum washing machine, minus the weight of the laundry in the drum after the duration of the deceleration stage of the dehydration program of the drum washing machine reaches the maximum deceleration duration; The change in the eccentricity value of the clothes in the drum before and after the driving motor decelerates is the eccentricity value of the clothes in the drum after the constant speed stage and before the deceleration stage of the dehydration program of the drum washing machine, minus the eccentricity value of the clothes in the drum after the duration of the deceleration stage of the dehydration program of the drum washing machine reaches the maximum deceleration duration.

6. The dehydration control method of a drum washing machine according to claim 5, characterized in that: The controlling the driving motor to first increase the speed and then decrease the speed comprises: Controlling the driving motor to increase the speed to the preset speed, and after maintaining the preset speed for a preset time, controlling the driving motor to decrease the speed; The deceleration acceleration of the driving motor is the deceleration acceleration of the previous unit time.

7. The dehydration control method of a drum washing machine according to claim 6, characterized in that: The controlling the driving motor to first increase the speed and then decrease the speed further comprises: Calculate the change value ΔU of the bus voltage per unit time j ; Calculate the current bus voltage change per unit time ΔU j And the change value of bus voltage per unit time ΔU j-1 The difference ΔU"=ΔU j -ΔU j-1 ; Determine whether the ΔU" is within a preset bus voltage range; When ΔU" is within a preset bus voltage interval, controlling the drum washing machine to end the dehydration procedure; When ΔU" is not within the preset bus voltage interval, the drive motor is controlled to keep decelerating until the deceleration time of the drive motor reaches the maximum deceleration time, and the drive motor is controlled to enter a fault judgment mode.

8. The dehydration control method of a drum washing machine according to claim 7, characterized in that: The controlling the driving motor to enter a fault determination mode comprises: Controlling the driving motor to stop running; Acquiring current power supply parameters of the power supply of the driving motor; Determining whether the current power supply parameter is within a preset power supply parameter range; Determining whether the drive motor is faulty according to a result of determining whether the current power supply parameter is within a preset power supply parameter range; The current power supply parameters of the power supply of the driving motor at least include the current power supply voltage and the current power supply frequency.

9. The dehydration control method of a drum washing machine according to claim 8, characterized in that: The determining whether the drive motor is faulty according to the result of judging whether the current power supply parameter is within the preset power supply parameter range comprises: When the current power supply voltage is within a preset power supply voltage range and the current power supply frequency is within a preset power supply frequency range, determining that the drive motor is faulty; When the current power supply voltage is not within the preset power supply voltage range and the current power supply frequency is not within the preset power supply frequency range, it is determined that the drive motor has no fault.

10. The dehydration control method of a drum washing machine according to claim 9, characterized in that: When it is determined that the drive motor has no fault, controlling the drive motor to first increase the speed and then decrease the speed further includes: The current power supply voltage and the current power supply frequency are adjusted so that the deceleration acceleration of the drive motor is the preset deceleration acceleration.

11. The dehydration control method of a drum washing machine according to claim 10, characterized in that: The next time the drum washing machine runs the dehydration program, the dehydration control method further includes: The power supply parameters of the power supply of the driving motor are adjusted so that the power supply parameters of the power supply of the driving motor next time are the same as the power supply parameters of the power supply of the driving motor this time.

12. A drum washing machine, characterized in that: The drum washing machine adopts the dehydration control method of the drum washing machine according to any one of claims 1 to 11; The drum washing machine comprises a drum and a driving motor, clothes can be placed in the drum, and the driving motor can drive the drum to rotate.

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