Household appliance and motor control method

Abstract

The invention is suitable for the technical field of motor control, and provides a household appliance and a motor control method, and the method comprises the steps: determining a first torque angle of a current control period according to a first torque angle and a disturbance value of a synchronous motor in a previous control period; determining a current component reference value corresponding to the current control period according to the first torque angle of the current control period and the stator current of the synchronous motor; and performing pulse signal injection on the synchronous motor according to the current component reference value corresponding to the current control period, wherein the pulse signal is used for driving the synchronous motor. According to the invention, the effect of controlling the maximum torque current ratio of the motor can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of motor control, and in particular to a household appliance and a motor control method. Background Art

[0002] Maximum torque per current ratio control (MTPA) is a control method that maximizes the ratio of torque to stator current vector. It is an important means to improve motor efficiency and optimize motor performance.

[0003] Currently, when realizing the maximum torque-to-current ratio control of a motor, the torque angle is usually calculated based on the derived motor operating parameters such as the AC and DC inductances, and then the motor is controlled based on the torque angle. However, during the operation of the motor, its actual operating parameters usually fluctuate with the changes in the motor operating conditions, that is, there is an error between the derived motor operating parameters and the actual motor operating parameters, which affects the effect of the maximum current-torque ratio control. Summary of the invention

[0004] The present application provides a household appliance and a motor control method, which can improve the effect of controlling the maximum torque current ratio of the motor.

[0005] In a first aspect, some embodiments of the present application provide a household appliance, including a housing, a synchronous motor, and a controller, wherein the synchronous motor is used to rotate according to a pulse signal, and the controller is configured to perform the following steps:

[0006] Determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value;

[0007] Determining a current component reference value corresponding to a current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor;

[0008] A pulse signal is injected into the synchronous motor according to the current component reference value corresponding to the current control cycle, and the pulse signal is used to drive the synchronous motor.

[0009] Since the controller directly calculates the first torque angle of the current control cycle based on the first torque angle and disturbance value of the synchronous motor in the previous control cycle during the process of controlling the synchronous motor, there is no need to calculate the first torque angle of the synchronous motor in the current control cycle based on the derived motor operating parameters. Therefore, the influence of the error of the derived motor operating parameters can be avoided and the accuracy of the obtained first torque angle can be improved. Furthermore, in the current control cycle, the current component reference value is calculated based on the first torque angle with higher accuracy and the stator current of the synchronous motor, and a pulse signal is injected into the synchronous motor based on the current component reference value to drive the synchronous motor. This can better improve the effect of maximum torque-to-current ratio control of the synchronous motor and help reduce the energy consumption of household appliances.

[0010] In a second aspect, an embodiment of the present application provides a motor control method, including:

[0011] In a third aspect, an embodiment of the present application provides a motor control device, comprising a module for executing the motor control method in the second aspect.

[0012] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer storage medium stores a computer program, and when the computer program is executed by a processor, the steps of the motor control method described in the second aspect are implemented.

[0013] In a fifth aspect, an embodiment of the present application provides a computer program product. When the computer program product is run on a household appliance, the household appliance executes the motor control method described in the second aspect above.

[0014] It can be understood that the beneficial effects of the second to fifth aspects mentioned above can be found in the relevant description of the first aspect mentioned above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1 A schematic diagram of an operation scenario between a household appliance and a control device provided in some embodiments of the present application;

[0017] Figure 2 A timing interaction diagram of a home appliance startup phase provided by some embodiments of the present application;

[0018] Figure 3A structural block diagram of a household appliance provided in some embodiments of the present application;

[0019] Figure 4 A schematic flow chart of a motor control method provided in some embodiments of the present application;

[0020] Figure 5 A flowchart of another motor control method provided in some embodiments of the present application;

[0021] Figure 6 A flowchart of another motor control method provided in some embodiments of the present application;

[0022] Figure 7 A flowchart of another motor control method provided in some embodiments of the present application;

[0023] Figure 8 A flowchart of another motor control method provided in some embodiments of the present application;

[0024] Fig. 9 A flowchart of another motor control method provided in some embodiments of the present application;

[0025] Fig.10 A structural block diagram of a motor control device provided in some embodiments of the present application. DETAILED DESCRIPTION

[0026] The following embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following embodiments do not represent all implementations consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims.

[0027] It should be noted that the brief description of terms in this application is only for the convenience of understanding the embodiments described below, and is not intended to limit the embodiments of this application. Unless otherwise specified, these terms should be understood according to their common and usual meanings.

[0028] The terms "first", "second", "third", etc. in the specification and claims of this application and the above drawings are used to distinguish similar or similar objects or entities, and do not necessarily mean to limit a specific order or sequence, unless otherwise noted. It should be understood that the terms used in this way can be interchangeable under appropriate circumstances.

[0029] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover but not exclude inclusion, for example, a product or device comprising a list of components is not necessarily limited to all the components expressly listed but may include other components not expressly listed or inherent to such product or device.

[0030] The term "module" refers to any known or later developed hardware, software, firmware, artificial intelligence, fuzzy logic, or combination of hardware and / or software code that is capable of performing the functions associated with that element.

[0031] Figure 1 Schematic diagram of operation scenarios between household appliances and control devices provided in some embodiments of the present application. Figure 1 As shown, the user can operate the home appliance 200 through a control device such as a smart device 300 or a control device 100.

[0032] In some embodiments, the household appliance 200 may be an appliance with a synchronous motor inside, such as a refrigerator, an air conditioner, or a washing machine. For example, the household appliance 200 may be an appliance that needs to run for a long time, such as an air conditioner or a refrigerator.

[0033] It should be noted that in the embodiment of the present application, the synchronous motor in the household appliance 200 is a motor without a position sensor.

[0034] In some embodiments, the control device 100 may be a remote controller or a smart home controller, etc. For example, the control device is a remote controller, and the communication method between the remote controller and the home appliance includes but is not limited to infrared protocol communication, Bluetooth protocol communication or other short-range communication methods, and the home appliance 200 is controlled wirelessly or wired. The user can input user commands through buttons on the remote controller, voice input or control panel input, etc. to control the home appliance 200.

[0035] In some embodiments, a smart device 300 (such as a mobile terminal, a tablet computer, a computer, an intelligent robot, etc.) can also be used to control the home appliance 200. For example, the home appliance 200 is controlled using an application running on the smart device.

[0036] In some embodiments, the household appliance may not use the above-mentioned smart device 300 or control device 100 to receive instructions, but may receive user control through buttons set on the household appliance.

[0037] In some embodiments, the household appliance 200 can also be controlled in ways other than the control device 100 and the smart device 300. For example, the user's voice command control can be directly received through a module for obtaining voice commands configured inside the household appliance 200, or the user's voice command control can be received through a voice control device set outside the household appliance 200.

[0038] In some related technologies, the energy efficiency of synchronous motors can be optimized by changing the electromagnetic design of synchronous motors, thereby improving the energy efficiency of household appliances, but it is heavily dependent on the coordinated design of the motor factory.

[0039] In other related technologies, the current measured by the synchronous motor can be used to calibrate the current in the motor mathematical model, and the AC and DC inductance and other operating parameters of the synchronous motor can be derived through the motor mathematical model. Based on this, the torque angle of the synchronous motor is calculated, and the maximum torque current ratio of the synchronous motor of the household appliance is controlled according to the torque angle to improve the energy efficiency of the household appliance. The above method can be used to improve the energy efficiency of household appliances without relying on the motor factory, but during the operation of the synchronous motor of the household appliance, its actual operating parameters fluctuate with the actual working conditions of the synchronous motor. There is a deviation between the operating parameters derived from the motor mathematical model and the actual operating parameters, which affects the motor operating efficiency and energy consumption, and thus affects the energy efficiency of the household appliance.

[0040] In order to improve the energy efficiency of household appliances without relying on motor factories, an embodiment of the present application provides a household appliance and motor control method. The method first determines a first torque angle of a current control cycle based on a first torque angle and a disturbance value of the synchronous motor in a previous control cycle, and then determines a current component reference value corresponding to the current control cycle based on the first torque angle of the current control cycle and the stator current of the synchronous motor. Then, a pulse signal is injected into the synchronous motor according to the current component reference value corresponding to the current control cycle to drive the synchronous motor of the household appliance. Since the first torque angle of the current control cycle is directly calculated based on the first torque angle and the disturbance value of the previous control cycle, it does not need to be calculated based on the motor operating parameters. Therefore, the influence of the errors in the motor operating parameters can be avoided, and the accuracy of the obtained first torque angle can be improved, so that the maximum torque-to-current ratio control effect of the synchronous motor can be better improved, which is beneficial to improving the energy efficiency of household appliances.

[0041] Figure 2 A timing interaction diagram of the startup phase of a household appliance 200 provided in some embodiments of the present application.

[0042] Reference Figure 2 , the user can start the household appliance and set the working parameters of the household appliance through the control device. After the household appliance is started, the controller of the household appliance will generate a control signal (such as a pulse signal) for the synchronous motor according to the set working parameters, and inject the generated control signal into the synchronous motor, and drive the synchronous motor through the control signal to make the household appliance reach the set working parameters. It should be understood that after the household appliance is started, the controller will continue to inject the control signal into the synchronous motor based on the set working parameters until the household appliance reaches the set working parameters.

[0043] It should be understood that after the startup phase, household appliances generally continue to operate in a stable operating mode or an energy-saving mode. In addition to the startup phase, the controller usually also controls the synchronous motor (i.e., injects a corresponding pulse signal into the synchronous motor) when the household appliances are in stable operation, operating parameter fluctuations (such as user modification of operating parameters), high load operation or energy-saving mode. At this time, the synchronous motor of the household appliance can also be controlled by the motor control method provided in the embodiment of the present application to optimize the performance and efficiency of the motor, thereby improving the energy efficiency of the household appliance.

[0044] Taking air conditioning as an example, suppose the user adjusts the temperature of the air conditioner from 25°C to 20°C through a smart device. At this time, the air conditioner detects that the indoor temperature is higher than the set temperature (i.e. 20°C) through a temperature sensor, etc. The controller needs to control the synchronous motor of the air conditioning compressor so that the speed of the synchronous motor of the compressor reaches the speed corresponding to the set temperature (assuming it is called the target speed) to make the indoor temperature reach the set temperature.

[0045] It should be understood that the control of the synchronous motor is usually a closed-loop control, generally including multiple control cycles. In one control cycle, the controller can determine the stator current of the synchronous motor in the control cycle according to the speed error (i.e., the deviation between the current actual speed of the synchronous motor and the target speed) and the proportional-integral controller (PI controller). The stator current is the current that the synchronous motor should generate in order to make the speed of the synchronous motor reach the target speed, so as to adjust the output torque of the motor by adjusting the stator current so that the actual speed is close to the target speed.

[0046] Among them, the controller adjusts the stator current of the synchronous motor by adjusting the pulse signal. In order to improve the energy efficiency of the air conditioner, the torque angle (i.e., the first torque angle) of the synchronous motor in the current control cycle is calculated by the motor control method provided in the embodiment of the present application, and the optimal current component of the stator current is calculated based on the first torque angle with higher accuracy to obtain the current component reference value, and then, a pulse signal is generated based on the current component reference value of the current control cycle, and the pulse signal is injected into the synchronous motor, and the synchronous motor is driven by the pulse signal, while changing the stator current of the synchronous motor, the synchronous motor can output the maximum torque that can be generated under the stator current, thereby achieving efficient speed control and torque output.

[0047] In order to facilitate further understanding of the technical solutions in some embodiments of the present application, the technical solutions of household appliances and motor control methods, as well as how the technical solutions solve the above-mentioned technical problems are described in detail below in combination with some specific embodiments and drawings. The various embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. Obviously, the described embodiments are part of the embodiments of the present application, not all of them.

[0048] Figure 3 It shows that some embodiments of the present application provide Figure 1 In the structural block diagram of the household appliance, for the convenience of explanation, only the parts related to the embodiment of the present application are shown.

[0049] Reference Figure 3 The household appliance includes a housing 310, a synchronous motor 320 and a controller 330.

[0050] The synchronous motor 320 is disposed in the housing 310 and is configured to rotate according to the pulse signal.

[0051] The controller 330 is configured to: determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value; determine the current component reference value corresponding to the current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor; and inject a pulse signal into the synchronous motor according to the current component reference value corresponding to the current control cycle.

[0052] Figure 4 A flow chart of a motor control method provided by some embodiments of the present application is shown. The above method is applied to the controller in the above household appliance, and is described in detail as follows:

[0053] S410. Determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value.

[0054] The above control cycle refers to the time interval for the controller to inject pulse signals into the synchronous motor. For example, the control cycle can be the time period from the time the controller injects a pulse signal into the synchronous motor to the time the next pulse signal injection is completed. For example, assuming that the controller completes the k-th pulse signal injection into the synchronous motor A at 12:10:00 and completes the k+1-th pulse signal injection into the synchronous motor A at 12:10:05, then the time period corresponding to the k+1-th control cycle can be 12:10:00-12:10:05, with a duration of 5 seconds.

[0055] Optionally, one control cycle of the synchronous motor may include one or more pulse signals, that is, the controller may inject one or more pulse signals when injecting the pulse signal of the current control cycle into the synchronous motor.

[0056] The torque angle refers to the angle between the stator current of the synchronous motor and the d-axis (also called the direct axis, which coincides with the magnetic pole axis of the synchronous motor), reflecting the distribution of the stator current on the direct axis and the quadrature axis (i.e., the q-axis).

[0057] It should be understood that the above disturbance value may be a preset fixed value or a dynamic value.

[0058] The disturbance value can be a value input into the controller by a user through a smart device, etc., or a value automatically generated by a pre-trained model such as a large model, or a value randomly generated by the controller through methods such as a random number algorithm. The embodiment of the present application does not impose any specific restrictions on the method of determining the disturbance value.

[0059] It should be understood that when the first torque angle of the current control cycle is calculated based on the first torque angle of the previous control cycle and the disturbance value, the specific calculation method can be determined according to the type of the disturbance value (such as angle value or angle change rate, etc.).

[0060] For example, when the disturbance value is the angle change rate, the angle change value can be calculated based on the torque angle and the angle change rate of the previous control cycle, and then the first torque angle of the current control cycle can be calculated based on the angle change value and the first torque angle of the previous control cycle.

[0061] In the embodiment of the present application, since there is no need to rely on the motor operating parameters for calculation in the process of determining the first torque angle of the synchronous motor in the current control cycle, the influence of factors such as the accuracy of the motor mathematical model and the motor operating conditions on the derived motor operating parameters can be better avoided, thereby obtaining a first torque angle with higher accuracy.

[0062] S420. Determine a current component reference value corresponding to the current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor.

[0063] The current component refers to the component of the current (ie, the stator current) passing through the stator winding when the motor is running. In the embodiment of the present application, the current component may include a d-axis component and a q-axis component that affect the output torque of the motor.

[0064] It should be understood that the stator current of the synchronous motor can be calculated through the mathematical model of the motor, or can be calculated based on the current measured by a current measuring device such as a Hall sensor, or can be predicted by an intelligent algorithm such as a regression algorithm or an observer algorithm.

[0065] As an example, when determining the stator current of the synchronous motor in the current control cycle, the controller can obtain the three-phase winding current of the synchronous motor measured by the current sensor, and input the three-phase winding current to the sliding film observer, which is used to estimate the current position angle and speed of the synchronous motor rotor according to the three-phase winding current, and obtain the rotor position angle and actual speed. The controller can use the estimated rotor position angle and actual speed as the input of the PI controller, and calculate the stator current of the current control cycle through the PI controller. In the above process of determining the stator current, the influence of the change of the rotor position angle of the synchronous motor on the dynamic characteristics of the synchronous motor is fully considered, the stator current is calculated in combination with the rotor position angle and the actual speed of the synchronous motor, and the sliding film observer with high-precision estimation and strong anti-interference ability is used to estimate the actual speed and rotor position angle of the synchronous motor, which can better ensure the accuracy of the obtained stator current.

[0066] As an example, the above current component reference value can be expressed as follows:

[0067]

[0068] represents the reference value of the d-axis current component, represents the reference value of the q-axis current component, represents the stator current of the synchronous motor (also called current vector), β represents the first torque angle of the current control cycle, and cos and sin are trigonometric functions.

[0069] It should be understood that the stator current of the synchronous motor is the current that the synchronous motor should generate in order to make the synchronous motor reach the target speed. According to the first torque angle of the current control cycle and the stator current, the current component required to generate the maximum torque under the stator current can be better calculated to obtain the current component reference value, so as to subsequently control the current of the synchronous motor based on the current component reference value to achieve the maximum torque-to-current ratio control of the synchronous motor.

[0070] S430. Inject a pulse signal into the synchronous motor according to the current component reference value corresponding to the current control cycle, where the pulse signal is used to drive the synchronous motor.

[0071] It should be understood that the controller can generate a pulse signal corresponding to the current component reference value based on a modulation technique such as pulse width modulation or a vector control method, and then apply the generated pulse signal to the inverter of the synchronous motor, and the inverter controls the stator current of the synchronous motor according to the pulse signal to make it track the current component reference value. Through the above steps, precise control of the synchronous motor can be achieved and its operating efficiency can be improved.

[0072] As an example, the controller can use a sinusoidal pulse modulation (SPWM) method to generate a pulse width modulation wave signal corresponding to a current component reference value, apply the pulse width modulation wave signal to a drive circuit of a power tube of a synchronous motor, and drive the synchronous motor to rotate by driving the power tube.

[0073] In the embodiment of the present application, since the controller directly calculates the first torque angle of the current control cycle based on the first torque angle and the disturbance value of the synchronous motor in the previous control cycle during the process of controlling the synchronous motor, there is no need to calculate the first torque angle of the synchronous motor in the current control cycle based on the derived motor operating parameters. Therefore, the influence of the error of the derived motor operating parameters can be avoided, and the accuracy of the obtained first torque angle can be improved. Furthermore, in the current control cycle, the current component reference value is calculated based on the first torque angle with higher accuracy and the stator current of the synchronous motor, and a pulse signal is injected into the synchronous motor based on the current component reference value to drive the synchronous motor. This can better improve the effect of maximum torque-to-current ratio control of the synchronous motor, which is beneficial to reducing the energy consumption of household appliances.

[0074] In some embodiments, before the above step S401, the above controller further performs the following steps:

[0075] The first torque angle of the first control cycle is determined according to the lead angle corresponding to the maximum torque of the synchronous motor.

[0076] The maximum torque of a synchronous motor is also called the stall torque, which usually refers to the maximum torque that the synchronous motor can produce within the normal working range, and can be expressed as the maximum torque under the rated current of the synchronous motor.

[0077] The lead angle refers to the angle at which the stator current of the synchronous motor leads the q axis. The lead angle corresponding to the maximum torque is the angle at which the stator current of the synchronous motor leads the q axis when the synchronous motor generates the maximum torque.

[0078] To improve the response efficiency of household appliances, in the first control cycle of the synchronous motor, the initial value of the first torque angle can be set according to the lead angle corresponding to the maximum torque of the synchronous motor (the initial value of the first torque angle is the value of the first torque angle in the first control cycle).

[0079] It should be understood that when setting the initial value of the first torque angle according to the lead angle corresponding to the maximum torque, the initial value of the first torque angle can be set to the lead angle corresponding to the maximum torque, or can be set to a larger angle determined based on the lead angle corresponding to the maximum torque (such as an angle greater than or equal to half of the lead angle).

[0080] As an example, considering that when a synchronous motor is started, the rotor is usually positioned on the axis of the A-phase winding of the stator first. At this time, the torque of the synchronous motor increases when the rotor position leads by 90°. Therefore, the first torque angle of the first control cycle can be set to 90°.

[0081] In the embodiment of the present application, since the first torque angle of the first control cycle is determined according to the lead angle corresponding to the maximum torque of the synchronous motor in the first control cycle, the synchronous motor can generate the maximum torque output in the initial stage of controlling the synchronous motor, and the torque angle of the synchronous motor is adjusted in the subsequent control cycles. This can more quickly and accurately approach the actual torque angle of the synchronous motor, speed up the response speed when household appliances are started or working parameters change, and optimize the efficiency of the synchronous motor.

[0082] In some embodiments, before the above step S401, the above controller further performs the following steps:

[0083] The disturbance value is determined according to the input angle information, or the disturbance value is determined according to the step angle of the synchronous motor.

[0084] The input angle information can be the angle information input into the controller by the user through a smart device or voice input, or it can be the angle information calculated and input into the controller by an intelligent computing module in a household appliance or other device such as an intelligent robot through an intelligent algorithm (such as a large model). The method for determining the angle information and the method for inputting the angle information into the controller can be set according to the actual application scenario, and no specific restrictions are made here.

[0085] The step angle of a synchronous motor refers to the angle at which the rotor rotates when the synchronous motor rotates according to a pulse signal.

[0086] As an example, the input angle information may be angle information input by a user, that is, the disturbance value of the current control cycle is set independently by the user, so as to meet the user's needs while achieving the maximum torque-to-current ratio control of the synchronous motor.

[0087] Alternatively, considering that the step angle is the angle at which the synchronous motor should rotate when it receives a pulse signal, and the actual rotation angle of the synchronous motor (i.e., the torque angle) may deviate due to factors such as load, the matching degree of the torque angle and the step angle will affect the control accuracy and dynamic performance of the synchronous motor. Therefore, in order to better match the dynamic performance of the synchronous motor so that it can better maintain a stable torque output under different working conditions, the disturbance value of the first torque angle can be determined according to the actual step angle of the synchronous motor, that is, the torque angle of the current control cycle is determined according to the torque angle of the previous control cycle and the step angle of the synchronous motor. The influence of the step angle on the torque angle is fully considered during the control process of the synchronous motor, which is conducive to improving the control accuracy of the motor and meeting various application requirements of household appliances.

[0088] It should be understood that, in the process of the controller controlling the synchronous motor, the disturbance values ​​corresponding to different control periods may be different values, and the manner of determining the disturbance values ​​in different control periods may also be different.

[0089] Figure 5 FIG. 2 shows a flow chart of another motor control method provided in some other embodiments. Figure 5 As shown, when the controller determines the disturbance value corresponding to the current control cycle, if the input angle information is obtained within a preset time period (such as within 10 seconds after the start of the current control cycle), the input angle information is used as the disturbance value of the current control cycle. If the input angle information within the preset time period is not obtained, the disturbance value corresponding to the current control cycle can be determined according to the step angle of the synchronous motor.

[0090] For example, a step angle of the synchronous motor can be used as the disturbance value corresponding to the current control cycle. For another example, the disturbance value can be calculated based on the target number and the step angle. The target number can be the number of pulse signals injected into the synchronous motor last time, or the input number.

[0091] Figure 6 FIG. 2 is a flow chart of another motor control method provided by some embodiments. Figure 6 As shown, the controller is configured to further perform the following steps:

[0092] S610. Determine a torque-to-current ratio difference corresponding to a current control cycle of the synchronous motor, wherein the torque-to-current ratio difference reflects a difference between torque-to-current ratios of two adjacent control cycles of the synchronous motor.

[0093] S620. Determine the disturbance direction according to the torque-current ratio difference.

[0094] S630. Determine the first torque angle of the current control cycle according to the first torque angle of the previous control cycle, the disturbance value and the disturbance direction.

[0095] The torque-to-current ratio refers to the ratio of the torque generated by the synchronous motor to the stator current, reflecting the ability of the synchronous motor to generate torque under a given stator current.

[0096] It should be noted that the torque-current ratio difference is a positive or negative value. The torque-current ratio difference corresponding to the current control cycle can be the difference calculated based on the torque-current ratio of the current control cycle and the torque-current ratio of the previous control cycle, or it can be the difference calculated based on the torque-current ratio of the previous control cycle and the torque-current ratio of the previous control cycle (i.e., the first two control cycles of the current control cycle) .

[0097] When determining the disturbance direction according to the torque current ratio difference, the disturbance direction can be determined according to the positive or negative of the torque current ratio difference. For example, it is assumed that the torque current ratio difference is calculated based on the torque current ratio of the current control cycle and the torque current ratio of the previous control cycle. If the torque current ratio difference is a positive number, it can be considered that the torque current ratio of the current control cycle is increased compared to the torque current ratio of the previous control cycle. At this time, the disturbance direction can be positive, and the first torque angle of the current control cycle determined is greater than the first torque angle of the previous control cycle. If the torque current ratio difference is a negative number, it can be considered that the torque current ratio of the current control cycle is reduced compared to the torque current ratio of the previous control cycle. At this time, the disturbance direction can be negative, and the first torque angle of the current control cycle determined is usually smaller than the first torque angle of the previous control cycle.

[0098] In an embodiment of the present application, the disturbance direction of the disturbance value is determined according to the direction of change of the torque-current ratio of the current control cycle relative to the torque-current ratio of the previous control cycle, so that when the current control cycle is determined according to the disturbance value and the previous control cycle, the first torque angle of the current control cycle can be determined in combination with the actual torque-current ratio control effect of the synchronous motor, thereby better tracking the maximum torque-current ratio of the synchronous motor, which is beneficial to improving the maximum torque-current ratio control effect.

[0099] Figure 7 FIG. 2 shows a flow chart of another motor control method provided by other embodiments. Figure 7 As shown, the controller is configured to further perform the following steps:

[0100] S710. Obtain at least one torque-to-current ratio difference value, where the at least one torque-to-current ratio difference value includes the torque-to-current ratio difference value corresponding to a current control period of the synchronous motor.

[0101] S720. Adjust the disturbance value according to the at least one torque-current ratio difference to obtain the adjusted disturbance value.

[0102] S730. Determine the first torque angle of the current control cycle according to the first torque angle of the previous control cycle and the adjusted disturbance value.

[0103] Since the torque-current ratio difference corresponding to the current control cycle can reflect the control effect corresponding to the previous control cycle, in the embodiment of the present application, the disturbance value is adjusted based on the torque-current ratio difference corresponding to the current control cycle, which is equivalent to dynamically adjusting the disturbance value in combination with the control effect of the previous control cycle. Furthermore, based on the adjusted disturbance value and the first torque angle of the previous control cycle, the accuracy of the first torque angle of the current control cycle can be improved, which is beneficial to improving the control effect of the current control cycle.

[0104] Alternatively, the torque-current ratio difference corresponding to multiple control cycles adjacent to the current control cycle can also be obtained, and the torque-current ratio difference corresponding to multiple consecutive control cycles can better reflect the recent control effect of the synchronous motor. Therefore, the disturbance value is adjusted according to the torque-current ratio difference corresponding to multiple control cycles consecutive to the current control cycle, and the first torque angle of the current control cycle is determined based on the adjusted disturbance value, which can further improve the accuracy of the obtained first torque angle.

[0105] For example, the torque-to-current ratio difference values ​​corresponding to N (greater than 2) consecutive control cycles of the current control cycle may be obtained, and the disturbance value may be adjusted according to the N torque-to-current ratio difference values ​​to obtain the adjusted disturbance value.

[0106] For example, assuming that N is 4 and the current control cycle is the 7th control cycle, the torque-current ratio difference corresponding to the 4th control cycle to the 7th control cycle can be obtained in the current control cycle, and 4 torque-current ratio differences can be obtained. The disturbance value of the current control cycle is adjusted according to these 4 torque-current ratio differences to obtain the adjusted disturbance value.

[0107] As an example, when the disturbance value is adjusted according to the torque-current ratio difference corresponding to the current control cycle, the adjustment direction of the disturbance value can be determined according to the positive or negative of the torque-current ratio difference, and then the adjustment coefficient of the disturbance value is determined according to the magnitude of the torque-current ratio difference, and the adjusted disturbance value is obtained according to the disturbance value, the adjustment direction and the adjustment coefficient. For example, the adjusted value is calculated according to the product of the disturbance value and the adjustment coefficient, and the adjusted disturbance value is obtained according to the adjusted value and the adjustment direction.

[0108] For example, when the torque-current ratio difference is a positive value, the adjustment direction of the disturbance value can be positive; when the torque-current ratio difference is a negative value, the adjustment direction of the disturbance value can be negative. At the same time, when the adjustment coefficient is determined according to the value of the torque-current ratio difference, if the value is less than the first threshold value (such as 0.8), it can be considered that the disturbance of the first torque angle of the previous control cycle is too small, so that the change of the torque-current ratio of the current control cycle is not obvious. At this time, the adjustment coefficient can be a larger first value (such as 2); if the value is greater than or equal to the first threshold value and less than the second threshold value (such as 2), it can be considered that the disturbance of the first torque angle of the previous control cycle is appropriate. At this time, the adjustment coefficient can be a second value (such as any value between 1 and 1.2); if the setting is greater than or equal to the second threshold value, it can be considered that the disturbance of the first torque angle of the previous control cycle is too large, so that the change of the torque-current ratio of the current control cycle is large, and the adjustment coefficient can be a smaller third value (such as 0.7).

[0109] As another example, the torque-current ratio difference corresponding to the next control cycle can be predicted based on multiple consecutive torque-current ratio differences, and then the disturbance value of the current control cycle can be adjusted based on the difference between the predicted torque-current ratio difference of the next control cycle and the expected torque-current ratio difference. The first torque angle of the current control cycle is determined based on the adjusted disturbance value and the first torque angle of the previous control cycle, and the current control cycle is controlled based on the first torque angle of the current control cycle, so that the actual torque-current ratio difference corresponding to the next control cycle is close to the expected torque-current ratio difference, thereby improving the maximum torque-current ratio control effect of the synchronous motor.

[0110] Figure 8 FIG. 4 shows a schematic diagram of a flow chart of adjusting the disturbance value in some other embodiments. Figure 8 As shown, when the controller performs the step of adjusting the disturbance value according to the at least one torque-current ratio difference to obtain the adjusted disturbance value, the controller is configured to perform the following steps:

[0111] S721. When the target difference reaches the lower limit of the difference, increase the disturbance value to obtain the adjusted disturbance value. The target difference is determined based on the at least one torque-current ratio difference.

[0112] S722. When the target difference reaches the upper limit of the difference, reduce the disturbance value to obtain the adjusted disturbance value.

[0113] It should be understood that the target difference value may be a torque current ratio difference value corresponding to the next control cycle predicted based on at least one torque current ratio difference value. Alternatively, when multiple torque current ratio difference values ​​are obtained, the target difference value may be a value determined based on the distribution characteristics of the multiple torque current ratio difference values. For example, the target difference value may be an average value of multiple torque current ratio difference values, or the variance may be calculated based on the torque current ratio difference values ​​other than the torque current ratio difference value of the current control cycle, and then the target difference value may be calculated based on the variance and the torque current ratio difference value of the current control cycle.

[0114] It should be noted that the target difference calculated in the embodiment of the present application is an absolute value.

[0115] It should be understood that when the target difference reaches the lower limit of the difference (such as), when the disturbance value needs to be increased, the adjustment coefficient of the disturbance value can be set to a value greater than 1 (such as 1.5); when the target difference reaches the upper limit of the difference and the disturbance value needs to be reduced, the adjustment coefficient of the disturbance value can be set to a value less than 1 (such as 0.5).

[0116] For example, when the target difference reaches the lower limit of the difference, the adjustment coefficient of the disturbance value may increase as the target difference decreases (such as linear increase, exponential increase, or logarithmic increase, etc.), and the adjustment coefficient is greater than 1; when the target difference reaches the upper limit of the difference, the adjustment coefficient of the disturbance value may decrease as the target difference increases (such as linear decrease, logarithmic decrease, or power function decrease, etc.).

[0117] In some embodiments, when the target difference value is between the difference lower limit value and the difference upper limit value, the adjustment coefficient may be 1, that is, the disturbance value may not be adjusted.

[0118] In some embodiments, when the controller determines the current component reference value corresponding to the current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor, the controller is further configured as follows:

[0119] When the above-mentioned first torque angle of the current control cycle is greater than or equal to the above-mentioned second torque angle of the synchronous motor in the current control cycle, the above-mentioned current component reference value is determined according to the above-mentioned first torque angle of the current control cycle and the above-mentioned stator current, and the above-mentioned second torque angle is calculated according to the weak magnetic control method.

[0120] The weak magnetic field control method is a control method that increases the speed of the synchronous motor by reducing the excitation flux of the synchronous motor. When household appliances require high speed or voltage balance, the controller can usually increase the speed of the synchronous motor through weak magnetic field control, while ensuring the stable operation of the synchronous motor.

[0121] The above-mentioned second torque angle can be a torque angle estimated by using the mathematical model of the motor based on the current and voltage input under weak magnetic control, or it can be a torque angle estimated according to the operating state and parameters of the synchronous motor using a weak magnetic control algorithm. The embodiment of the present application does not impose any specific restrictions on the specific calculation method of calculating the second torque angle according to the weak magnetic control method.

[0122] It should be understood that before determining the current component reference value, the torque angle is calculated based on the first torque angle of the previous control cycle and the disturbance value of the current control cycle to obtain the first torque angle of the current control cycle, and the torque angle is calculated based on the weak magnetic control mode to obtain the second torque angle of the current control cycle. It should be understood that the first torque angle is the torque angle corresponding to the maximum torque current ratio control mode, and the second torque angle is the torque angle corresponding to the weak magnetic control mode.

[0123] After obtaining the first torque angle and the second torque angle of the current control cycle, the calculation method of the current component reference value can be determined according to the size relationship between the first torque angle and the second torque angle, that is, it is equivalent to determining the control method of the current control cycle according to the size relationship between the first torque angle and the second torque angle.

[0124] It should be understood that when the current component reference value corresponding to the current control cycle is calculated based on the first torque angle and the stator current, the control mode of the current control cycle is the maximum torque current ratio control mode; when the current component reference value corresponding to the current control cycle is calculated based on the second torque angle and the stator current, the control mode of the current control cycle is the weak magnetic control mode.

[0125] It should be understood that when the first torque angle of the current control cycle is smaller than the second torque angle of the synchronous motor in the current control cycle, the current component reference value corresponding to the current control cycle can be determined based on the second torque angle of the current control cycle and the stator current.

[0126] In the embodiment of the present application, the control method adopted in the current control cycle is determined according to the size of the torque angles corresponding to the two control methods, and the current component reference value corresponding to the current control cycle is calculated based on the larger torque angle, so that in the process of controlling the synchronous motor of the household appliance, the energy consumption and operation stability of the synchronous motor can be considered at the same time, and the control method suitable for the control cycle can be selected to control the synchronous motor, thereby achieving a better control effect, which is beneficial to practical application.

[0127] Fig. 9 FIG. 2 is a flow chart of another motor control method provided in some embodiments. Fig. 9As shown, in this embodiment, when the first torque angle of the current control cycle is equal to the second torque angle, the controller may calculate the current component reference value of the current control cycle according to the second torque angle of the current control cycle and the stator current of the synchronous motor. That is, when the first torque angle and the second torque angle of the current control cycle are the same, the magnetic field weakening control mode may be given priority, and the current component reference value may be calculated according to the second torque angle corresponding to the magnetic field weakening control mode, so as to realize the control of the synchronous motor in the current control cycle through the magnetic field weakening control mode, ensure the stability and safety of the operation of the synchronous motor, and help improve the operation stability and safety of household appliances.

[0128] Corresponding to the motor control method described in the above embodiment, Fig.10 A structural block diagram of a motor control device provided in an embodiment of the present application is shown. For ease of explanation, only the parts related to the embodiment of the present application are shown.

[0129] Reference Fig.10 The device includes: a first torque angle calculation module 1010, a current component reference value calculation module 1020 and a control module 1030.

[0130] The first torque angle calculation module 1010 is used to determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value.

[0131] The current component reference value calculation module 1020 is used to determine the current component reference value corresponding to the current control cycle according to the above-mentioned first torque angle of the current control cycle and the stator current of the above-mentioned synchronous motor.

[0132] The control module 1030 is used to inject a pulse signal into the synchronous motor according to the current component reference value corresponding to the current control cycle, and the pulse signal is used to drive the synchronous motor.

[0133] It should be noted that the information interaction, execution process, etc. between the above-mentioned devices / units are based on the same concept as the method embodiment of the present application. Their specific functions and technical effects can be found in the method embodiment part and will not be repeated here.

[0134] The embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and when the computer program is executed by a controller, the steps in the above-mentioned method embodiments can be implemented.

[0135] An embodiment of the present application provides a computer program product. When the computer program product runs on a controller, the controller can implement the steps of the motor control method described in the above embodiments when executing the computer program product.

[0136] 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 present application implements all or part of the processes in the above-mentioned embodiment method, which can be completed by instructing the relevant hardware through a computer program. The computer program can be stored in a computer-readable storage medium, and the computer program can implement the steps of the above-mentioned various method embodiments when executed by the processor. Among them, the computer program includes computer program code, and the computer program code can be in source code form, object code form, executable file or some intermediate form. The computer-readable medium may at least include: any entity or device that can carry the computer program code to the camera / electronic device, recording medium, computer memory, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium. For example, a USB flash drive, a mobile hard disk, a magnetic disk or an optical disk. In some jurisdictions, according to legislation and patent practice, computer-readable media cannot be electric carrier signals and telecommunication signals.

[0137] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0138] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0139] In the embodiments provided in the present application, it should be understood that the disclosed devices / network equipment and methods can be implemented in other ways. For example, the device / network equipment embodiments described above are merely schematic. For example, the division of the modules or units is only a logical function division. There may be other division methods in actual implementation, such as 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.

[0140] 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 solution of this embodiment.

[0141] The embodiments described above are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, a person skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present application, and should all be included in the protection scope of the present application.

Claims

1. A household appliance, characterized in that: include: case; a synchronous motor, disposed in the housing and configured to rotate according to a pulse signal; The controller is configured as: Determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value; Determining a current component reference value corresponding to a current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor; A pulse signal is injected into the synchronous motor according to the current component reference value corresponding to the current control cycle, and the pulse signal is used to drive the synchronous motor.

2. The household appliance according to claim 1, characterized in that: Before determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value, the controller is further configured to: The disturbance value is determined according to input angle information, or the disturbance value is determined according to a step angle of the synchronous motor.

3. The household appliance according to claim 1, characterized in that: Before determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value, the controller is further configured to: Determine a torque-to-current ratio difference corresponding to a current control cycle of the synchronous motor, wherein the torque-to-current ratio difference reflects a difference between torque-to-current ratios of two adjacent control cycles of the synchronous motor; Determining a disturbance direction according to the torque-current ratio difference; Correspondingly, determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value includes: The first torque angle of a current control cycle is determined according to the first torque angle of a previous control cycle, the disturbance value, and the disturbance direction.

4. The household appliance according to claim 1, characterized in that: Before determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value, the controller is further configured to: Acquire at least one torque-to-current ratio difference value, wherein the at least one torque-to-current ratio difference value comprises the torque-to-current ratio difference value corresponding to a current control cycle of the synchronous motor; Adjusting the disturbance value according to the at least one torque-current ratio difference to obtain the adjusted disturbance value; Correspondingly, determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value includes: The first torque angle of the current control cycle is determined according to the first torque angle of the previous control cycle and the adjusted disturbance value.

5. The household appliance according to claim 4, characterized in that: When the disturbance value is adjusted according to the at least one torque-current ratio difference to obtain the adjusted disturbance value, the controller is configured as follows: When the target difference reaches the lower limit of the difference, increasing the disturbance value to obtain the adjusted disturbance value, wherein the target difference is determined according to the at least one torque-current ratio difference; When the target difference reaches the upper limit of the difference, the disturbance value is reduced to obtain the adjusted disturbance value.

6. The household appliance according to claim 1, characterized in that: The controller is also configured to: The first torque angle of the first control cycle is determined according to the lead angle corresponding to the maximum torque of the synchronous motor.

7. The household appliance according to any one of claims 1 to 6, characterized in that: When determining the current component reference value corresponding to the current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor, the controller is configured as follows: When the first torque angle of the current control cycle is greater than or equal to the second torque angle of the synchronous motor in the current control cycle, the current component reference value is determined according to the first torque angle of the current control cycle and the stator current, and the second torque angle is calculated according to the weak magnetic control method.

8. A motor control method, characterized in that: include: Determine the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value; Determining a current component reference value corresponding to a current control cycle according to the first torque angle of the current control cycle and the stator current of the synchronous motor; A pulse signal is injected into the synchronous motor according to the current component reference value corresponding to the current control cycle, and the pulse signal is used to drive the synchronous motor.

9. The motor control method according to claim 8, characterized in that: Before determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value, the method further includes: The disturbance value is determined according to input angle information, or the disturbance value is determined according to a step angle of the synchronous motor.

10. The motor control method according to claim 8 or 9, characterized in that: Before determining the first torque angle of the current control cycle according to the first torque angle of the synchronous motor in the previous control cycle and the disturbance value, the method further includes: The first torque angle of the first control cycle is determined according to the lead angle corresponding to the maximum torque of the synchronous motor.

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