Motor control method and device and household appliance

Abstract

The invention discloses a motor control method and device and a household appliance, and the method comprises the steps: detecting the load current of a motor, and adjusting a modulation mode for controlling the motor through employing a first modulation strategy or a second modulation strategy according to whether the load current of the motor is greater than a preset threshold value or not. According to the motor control system adopting the scheme, the motor can be controlled by adopting different modulation modes according to different conditions, the harmonic content of direct current bus current can be effectively reduced, a bus capacitor with a smaller capacitance value can be selected in the design of the control system, the cost of the control system is further reduced, and the control efficiency is improved. Therefore, the efficiency and the cost of the control system can be considered.

Description

Technical Field

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

[0002] Various motors are commonly used in household appliances. For example, permanent magnet synchronous motors are used in dryers, and the motors are controlled by a control system.

[0003] The control system usually includes a main circuit and a microprocessor platform. The main circuit includes a DC bus, bus capacitors, and an inverter composed of power switch semiconductor devices. The microprocessor platform uses various control algorithms to collect and process signals such as motor speed, motor current, and DC bus voltage. According to the required speed or torque command, it controls the on and off of the power semiconductor devices in the main circuit to perform PWM (Pulse Width Modulation) modulation to adjust the amplitude and frequency of the AC voltage acting on the motor, thereby achieving control of the motor speed or torque.

[0004] In the design of permanent magnet synchronous motor control system, space vector modulation (SVM) is usually used to control the waveform of motor phase voltage. Different motor modulation methods will affect the harmonic size of motor current, the switching loss of inverter and the size of harmonic current flowing through DC bus, which will affect the design and selection of bus capacitor value. The cost of bus capacitors with different capacitance values ​​is different. Therefore, how to achieve the optimal design of control system to reduce cost is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0005] In view of this, the embodiments of the present application provide a motor control method, device, household appliance and storage medium to solve at least one of the above technical problems.

[0006] A first aspect of the present application provides a motor control method, including:

[0007] Detect the load current of the motor;

[0008] According to the load current of the motor being greater than a preset threshold, adjusting the modulation mode of controlling the motor according to the first modulation strategy;

[0009] According to the load current of the motor being less than or equal to a preset threshold, the modulation mode for controlling the motor is adjusted according to the second modulation strategy.

[0010] The motor control method of the first aspect of the present application embodiment detects whether the load current of the motor is greater than a preset threshold, and adjusts the modulation method of controlling the motor by adopting the first modulation strategy or the second modulation strategy according to whether the load current of the motor is greater than the preset threshold. Compared with the prior art, the motor control system can adopt different modulation methods to control the motor according to different conditions, and can effectively reduce the harmonic content of the DC bus current. In the control system design, a bus capacitor with a smaller capacitance can be selected, thereby reducing the cost of the control system. Therefore, the present application can take into account both the efficiency and cost of the control system.

[0011] In some embodiments of the present application, adjusting the modulation mode of controlling the motor according to the first modulation strategy based on the load current of the motor being greater than a preset threshold includes:

[0012] According to the load current of the motor being greater than a preset threshold, the modulation mode of controlling the motor is adjusted to the MC-GDPWM modulation mode.

[0013] In some embodiments of the present application, adjusting the modulation mode of controlling the motor according to the second modulation strategy based on the load current of the motor being less than or equal to a preset threshold value includes:

[0014] According to the load current of the motor being less than or equal to a preset threshold, the current modulation ratio of the motor is obtained;

[0015] The modulation mode of controlling the motor is adjusted according to whether the current modulation ratio is greater than the preset ratio.

[0016] In some embodiments of the present application, adjusting the modulation mode of controlling the motor according to whether the current modulation ratio is greater than a preset ratio includes:

[0017] According to the current modulation ratio being greater than the preset ratio, the modulation mode of the control motor is adjusted to the DPWM modulation mode;

[0018] According to the current modulation ratio being less than or equal to the preset ratio, the modulation mode of controlling the motor is adjusted to the SVM modulation mode.

[0019] In some embodiments of the present application, the preset ratio is determined as follows:

[0020] Acquire a plurality of preset candidate modulation ratios;

[0021] Traversing the plurality of candidate modulation ratios, and selecting at least one target modulation ratio that meets a preset condition;

[0022] Using the smallest target modulation ratio among the at least one target modulation ratio as a preset ratio;

[0023] The pre-conditions are as follows:

[0024] The current modulation ratio is greater than the target modulation ratio, and the motor phase current harmonics using the DPWM modulation method are smaller than the motor phase current harmonics using the SVM modulation method;

[0025] The current modulation ratio is less than or equal to the target modulation ratio, and the motor phase current harmonics using the SVM modulation method are less than or equal to the motor phase current harmonics using the DPWM modulation method.

[0026] The motor control device of the second embodiment of the present application includes:

[0027] A detection module, used for detecting the load current of the motor;

[0028] The adjustment module is used to adjust the modulation mode of controlling the motor according to the first modulation strategy when the load current of the motor is greater than a preset threshold; and to adjust the modulation mode of controlling the motor according to the second modulation strategy when the load current of the motor is less than or equal to the preset threshold.

[0029] The motor control device of the second aspect of the embodiment of the present application detects whether the load current of the motor is greater than a preset threshold value, and adjusts the modulation method of controlling the motor by adopting the first modulation strategy or the second modulation strategy according to whether the load current of the motor is greater than the preset threshold value. Compared with the prior art, the motor control system can adopt different modulation methods to control the motor according to different conditions, and can effectively reduce the harmonic content of the DC bus current. In the control system design, a bus capacitor with a smaller capacitance can be selected, thereby reducing the cost of the control system. Therefore, the present application can take into account both the efficiency and cost of the control system.

[0030] In some embodiments of the present application, the adjustment module is specifically used to:

[0031] According to the load current of the motor being greater than a preset threshold, the modulation mode of controlling the motor is adjusted to the MC-GDPWM modulation mode.

[0032] In some embodiments of the present application, the adjustment module is specifically used to:

[0033] According to the load current of the motor being less than or equal to a preset threshold, the current modulation ratio of the motor is obtained;

[0034] The modulation mode of controlling the motor is adjusted according to whether the current modulation ratio is greater than the preset ratio.

[0035] In some embodiments of the present application, the adjustment module is specifically used to:

[0036] According to the current modulation ratio being greater than the preset ratio, the modulation mode of the control motor is adjusted to the DPWM modulation mode;

[0037] According to the current modulation ratio being less than or equal to the preset ratio, the modulation mode of controlling the motor is adjusted to the SVM modulation mode.

[0038] In some embodiments of the present application, the preset ratio is determined as follows:

[0039] Acquire a plurality of preset candidate modulation ratios;

[0040] Traversing the plurality of candidate modulation ratios, and selecting at least one target modulation ratio that meets a preset condition;

[0041] Using the smallest target modulation ratio among the at least one target modulation ratio as a preset ratio;

[0042] The pre-conditions are as follows:

[0043] The current modulation ratio is greater than the target modulation ratio, and the motor phase current harmonics using the DPWM modulation method are smaller than the motor phase current harmonics using the SVM modulation method;

[0044] The current modulation ratio is less than or equal to the target modulation ratio, and the motor phase current harmonics using the SVM modulation method are less than or equal to the motor phase current harmonics using the DPWM modulation method.

[0045] The household appliance of the third aspect embodiment of the present application adopts the motor control method of the first aspect embodiment of the present application.

[0046] The household appliance of the fourth aspect embodiment of the present application includes: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the motor control method of the first aspect embodiment.

[0047] The computer-readable storage medium of the fifth embodiment of the present application has computer-readable instructions stored thereon, and the computer-readable instructions can be executed by a processor to implement the motor control method of the first embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings:

[0049] Attached Figure 1 It shows the harmonic magnitude of phase current corresponding to different modulation modes under different modulation ratios;

[0050] Attached Figure 2 A flow chart of a motor control method according to an embodiment of the present application is shown;

[0051] Attached Figure 3 A flowchart of a specific motor modulation method of an embodiment of the present application is shown;

[0052] Attached Figure 4 A schematic diagram of a motor control device according to an embodiment of the present application is shown.

[0053] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0054] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0055] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0056] In addition, in the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0057] In the present invention, unless otherwise clearly specified and limited, the terms "connection", "fixation", etc. should be understood in a broad sense. For example, "fixation" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0058] In addition, the technical solutions between the various embodiments of the present invention can be combined with each other, but it must be based on the fact that ordinary technicians in the field can implement it. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0059] Taking SVM modulation as an example, at a smaller voltage modulation depth or modulation ratio, the motor harmonic current is smaller than that of discontinuous pulse width modulation (DPWM). However, at a larger modulation depth, the motor harmonic current is larger than that of discontinuous modulation. Figure 1 Shown are different modulation ratios m i Under different modulation modes (SVM, DPWM0 / 2, DPWM1 and DPWM3), the harmonic magnitude of the phase current corresponds to. Figure 1 It can be seen that when the modulation ratio m i <0.8, the motor phase current harmonics are smaller when SVM modulation is used, while the phase current harmonics are larger when DPWM modulation is used; when the modulation ratio m i >0.8, on the contrary, the motor phase current harmonics are larger when SVM modulation is used, while the phase current harmonics are smaller when DPWM modulation is used. The motor phase current harmonic components will affect the switching loss of the inverter, the motor loss, that is, the efficiency, and the electromagnetic interference. Therefore, in order to achieve optimized performance, the SVM modulation method is suitable for low modulation depth, and the DPWM modulation method is suitable for high modulation depth.

[0060] In addition, the design and selection of bus capacitor capacitance is positively correlated with the harmonic current flowing through the DC bus, so the maximum load current condition needs to be considered to design the bus capacitor capacitance. Therefore, under different speed regulation and load conditions, considering efficiency, loss and cost factors comprehensively, different modulation methods need to be adopted according to different conditions to achieve the goal of optimal design.

[0061] Based on the above analysis, the present application proposes a motor control method, device, household appliance and storage medium. By detecting whether the load current of the motor is greater than a preset threshold, the modulation method of controlling the motor is adjusted by using a first modulation strategy or a second modulation strategy according to whether the load current of the motor is greater than the preset threshold. Compared with the prior art, the motor control system can adopt different modulation methods to control the motor according to different conditions, and can effectively reduce the harmonic content of the DC bus current. In the control system design, a bus capacitor with a smaller capacitance can be selected, thereby reducing the cost of the control system. Therefore, the present application can take into account both the efficiency and cost of the control system.

[0062] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the specific embodiments of the present application are described in detail below with reference to the accompanying drawings.

[0063] Embodiment 1

[0064] Figure 2 is a flow chart of a motor control method provided in an embodiment of the present application, such as Figure 2 As shown, the motor control method includes:

[0065] Step S101: Detect the load current of the motor.

[0066] Step S102: According to the load current of the motor being greater than a preset threshold, the modulation mode for controlling the motor is adjusted according to the first modulation strategy.

[0067] Step S103: According to the load current of the motor being less than or equal to a preset threshold, the modulation mode for controlling the motor is adjusted according to the second modulation strategy.

[0068] The load current of the motor refers to the stator current value actually detected when the motor drags the load, and this value changes with the size of the load. The load current can be converted into torque. In the control system, the bus capacitance value is determined by the maximum load current or torque operating point. At this operating point, compared with the SVM modulation method and the ordinary DPWM method, the dual-carrier DPWM (Multiple Carrier GDPWM, MC-GDPWM) modulation method can effectively reduce the harmonic content of the DC bus current. Therefore, the control system can be optimized by adjusting the modulation method. First, in step S101, it is detected whether the load current of the motor is greater than a preset threshold value. The preset threshold value can be an empirical value set according to the maximum load current and the torque operating point, or it can be an experimental value obtained by experiment. According to the preset threshold value, the modulation method of the control motor is adjusted to optimize the control system. For example, the maximum load current is 10A, and the preset threshold value is set to 8A. When the load current of the motor exceeds 8A, it means that the motor is in a heavy load state. At this time, a modulation method suitable for the heavy load state can be selected to reduce the harmonic content of the DC bus current, thereby reducing the bus capacitance and reducing the control system cost.

[0069] There are many ways to detect the motor load current. For example, the motor load current can be collected by a pre-installed current sensor, and the current sensor can specifically be a phase current sensor. In practical applications, the motor load current measurement method can be selected according to actual conditions, and this application does not limit it.

[0070] In the present application, a first modulation strategy is pre-set for use when the load current of the motor is greater than a preset threshold, and a second modulation strategy is pre-set when the load current of the motor is less than or equal to the preset threshold. The first modulation strategy and the second modulation strategy indicate how to adjust the modulation method for controlling the motor in the corresponding situations so as to effectively reduce the harmonic content of the DC bus current.

[0071] In step S102, according to the load current of the motor being greater than a preset threshold, the modulation mode for controlling the motor is adjusted according to the first modulation strategy. In some implementations, when the load current of the motor is greater than the preset threshold, the modulation mode for controlling the motor can be adjusted to a MC-GDPWM modulation mode, because when the load current of the motor is greater than the preset threshold, the MC-GDPWM modulation mode can effectively reduce the harmonic content of the DC bus current compared with the SVM modulation mode and the ordinary DPWM modulation mode.

[0072] In step S103, the current modulation ratio of the motor is obtained according to whether the load current of the motor is less than or equal to a preset threshold value; and the modulation mode of controlling the motor is adjusted according to whether the current modulation ratio is greater than a preset ratio. In some implementations, when the current modulation ratio of the motor is greater than the preset ratio, the modulation mode of controlling the motor can be adjusted to a DPWM modulation mode, and when the current modulation ratio of the motor is less than or equal to the preset ratio, the modulation mode of controlling the motor can be adjusted to a SVM modulation mode.

[0073] Specifically, the above preset ratio is determined as follows:

[0074] The current modulation ratio is greater than the preset ratio, and the motor phase current harmonics corresponding to the DPWM modulation mode are smaller than the motor phase current harmonics corresponding to the SVM modulation mode;

[0075] The current modulation ratio is less than or equal to the preset ratio, and the motor phase current harmonics corresponding to the SVM modulation mode are less than or equal to the motor phase current harmonics corresponding to the DPWM modulation mode.

[0076] Specifically, the above preset ratio may also be determined in the following manner:

[0077] Acquire a plurality of preset candidate modulation ratios;

[0078] Traversing the plurality of candidate modulation ratios, and selecting at least one target modulation ratio that meets a preset condition;

[0079] Using the smallest target modulation ratio among the at least one target modulation ratio as a preset ratio;

[0080] The pre-conditions are as follows:

[0081] The current modulation ratio is greater than the target modulation ratio, and the motor phase current harmonics using the DPWM modulation method are smaller than the motor phase current harmonics using the SVM modulation method;

[0082] The current modulation ratio is less than or equal to the target modulation ratio, and the motor phase current harmonics using the SVM modulation method are less than or equal to the motor phase current harmonics using the DPWM modulation method.

[0083] For example, multiple candidate modulation ratios may be preset according to actual conditions, such as 0.6, 0.7, 0.8, and 0.9. Figure 1 It can be seen that the target modulation ratios that meet the above preset conditions are 0.8 and 0.9, and the smallest 0.8 is used as the preset ratio.

[0084] For example, see Figure 1 , when the modulation ratio m i ≤0.8, the motor phase current harmonics are small when the SVM modulation mode is used, which is less than or equal to the motor phase current harmonics corresponding to the DPWM modulation mode; when the modulation ratio m i >0.8, on the contrary, the motor phase current harmonics are larger when the SVM modulation method is used, which is larger than the motor phase current harmonics corresponding to the DPWM modulation method. Therefore, the preset ratio can be set to 0.8. Of course, the preset ratio can also be determined through relevant experiments.

[0085] For ease of understanding, this application provides Figure 3 A specific flow chart of adjusting the motor modulation method is shown in FIG. Figure 3 As shown, first detect the load current i of the motor l Is it greater than the preset threshold i l-th , when the load current i l Greater than the preset threshold i l-th When the load current i l Not greater than the preset threshold i l-th Calculate the current modulation ratio m of the motor i , if the current modulation ratio m i Greater than the preset ratio m i-th , using DPWM modulation, if the current modulation ratio m i Not greater than the preset ratio m i-th , using SVM modulation.

[0086] In addition to affecting the harmonic components of the motor phase current and switching losses, the selection of different modulation methods will also affect the design of the bus capacitor capacitance. The present application selects different modulation methods during the control process according to different load current and voltage modulation ratios, thereby reducing the size of the phase current harmonic current components during the motor's operating cycle, reducing switching losses, and improving the control system efficiency. At the same time, it reduces the bus capacitor capacity requirements and reduces system costs.

[0087] The motor control method of the present application can be applied to any permanent magnet synchronous drive application, not just the dryer compressor application. At the same time, the present application can also be extended to different motor types. In addition to permanent magnet synchronous motors, it can also be applied to other motor applications such as asynchronous motors and synchronous reluctance motors.

[0088] The motor control method of the embodiment of the present application detects whether the load current of the motor is greater than a preset threshold value, and adjusts the modulation method of controlling the motor by adopting the first modulation strategy or the second modulation strategy according to whether the load current of the motor is greater than the preset threshold value. Compared with the prior art, the motor control system can adopt different modulation methods to control the motor according to different conditions, and can effectively reduce the harmonic content of the DC bus current. In the control system design, a bus capacitor with a smaller capacitance can be selected, thereby reducing the cost of the control system. Therefore, the present application can take into account both the efficiency and cost of the control system.

[0089] Embodiment 2

[0090] The embodiment of the present application provides a motor control device, which corresponds to the motor control method of the first embodiment. For the relevant parts, please refer to the partial description of the first embodiment. The method embodiment described below is only illustrative.

[0091] Figure 4 is a schematic diagram of a motor control device provided in an embodiment of the present application, such as Figure 4 As shown, the device 10 comprises:

[0092] A detection module 101 is used to detect the load current of the motor;

[0093] The adjustment module 102 is used to adjust the modulation mode of controlling the motor according to the first modulation strategy when the load current of the motor is greater than the preset threshold; and to adjust the modulation mode of controlling the motor according to the second modulation strategy when the load current of the motor is less than or equal to the preset threshold.

[0094] In some embodiments of the present application, the adjustment module 102 is specifically configured to:

[0095] According to the load current of the motor being greater than a preset threshold, the modulation mode of controlling the motor is adjusted to the MC-GDPWM modulation mode.

[0096] In some embodiments of the present application, the adjustment module 102 is specifically configured to:

[0097] According to the load current of the motor being less than or equal to a preset threshold, the current modulation ratio of the motor is obtained;

[0098] The modulation mode of controlling the motor is adjusted according to whether the current modulation ratio is greater than the preset ratio.

[0099] In some embodiments of the present application, the adjustment module 102 is specifically configured to:

[0100] According to the current modulation ratio being greater than the preset ratio, the modulation mode of the control motor is adjusted to the DPWM modulation mode;

[0101] According to the current modulation ratio being less than or equal to the preset ratio, the modulation mode of controlling the motor is adjusted to the SVM modulation mode.

[0102] In some embodiments of the present application, the preset ratio is determined as follows:

[0103] Acquire a plurality of preset candidate modulation ratios;

[0104] Traversing the plurality of candidate modulation ratios, and selecting at least one target modulation ratio that meets a preset condition;

[0105] Using the smallest target modulation ratio among the at least one target modulation ratio as a preset ratio;

[0106] The pre-conditions are as follows:

[0107] The current modulation ratio is greater than the target modulation ratio, and the motor phase current harmonics using the DPWM modulation method are smaller than the motor phase current harmonics using the SVM modulation method;

[0108] The current modulation ratio is less than or equal to the target modulation ratio, and the motor phase current harmonics using the SVM modulation method are less than or equal to the motor phase current harmonics using the DPWM modulation method.

[0109] The motor control device of this embodiment detects whether the load current of the motor is greater than a preset threshold value, and adjusts the modulation method of controlling the motor by adopting the first modulation strategy or the second modulation strategy according to whether the load current of the motor is greater than the preset threshold value. Compared with the prior art, the motor control system can adopt different modulation methods to control the motor according to different conditions, and can effectively reduce the harmonic content of the DC bus current. In the control system design, a bus capacitor with a smaller capacitance can be selected, thereby reducing the cost of the control system. Therefore, the present application can take into account both the efficiency and cost of the control system.

[0110] Embodiment 3

[0111] The present application also provides a home appliance, which adopts the motor control method of any implementation in Example 1. The home appliance can be a washing machine, a dryer, or a washer-dryer, or other types, which are not limited in the present application.

[0112] The household appliance provided in the embodiment of the present application and the motor control method provided in the embodiment of the present application are based on the same inventive concept and have the same beneficial effects as the methods adopted, operated or implemented therein.

[0113] Embodiment 4

[0114] The embodiment of the present application also provides a household appliance, including: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the motor control method of any implementation method in Embodiment 1. The household appliance may be a household appliance such as a washing machine or a washer-dryer, or other types, which are not limited in the present application.

[0115] Specifically, the household appliance may include: a processor, a memory, a bus and a communication interface, and the processor, the communication interface and the memory are connected via a bus; the memory stores a computer program that can be run on the processor, and when the processor runs the computer program, it executes the motor control method provided in any of the foregoing embodiments of the present application.

[0116] The memory may include high-speed random access memory (RAM), and may also include non-volatile memory, such as at least one disk memory. The communication connection between the system network element and at least one other network element is realized through at least one communication interface (which may be wired or wireless), and the Internet, wide area network, local area network, metropolitan area network, etc. may be used.

[0117] The bus may be an ISA bus, a PCI bus or an EISA bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. The memory is used to store a program, and the processor executes the program after receiving an execution instruction. The motor control method disclosed in any implementation of the above-mentioned embodiment of the present application may be applied to the processor, or implemented by the processor.

[0118] The processor may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method can be completed by an integrated logic circuit of hardware in the processor or an instruction in the form of software. The above processor may be a general-purpose processor, including a central processing unit (CPU), a network processor (NP), etc.; it may also be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a readily available programmable gate array (FPGA) or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components. The methods, steps and logic block diagrams disclosed in the embodiments of the present application can be implemented or executed. The general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc. The steps of the method disclosed in the embodiments of the present application can be directly embodied as a hardware decoding processor to be executed, or a combination of hardware and software modules in the decoding processor to be executed. The software module may be located in a mature storage medium in the field such as a random access memory, a flash memory, a read-only memory, a programmable read-only memory or an electrically erasable programmable memory, a register, etc. The storage medium is located in a memory, and the processor reads the information in the memory and completes the steps of the above method in combination with its hardware.

[0119] The household appliance provided in the embodiment of the present application and the motor control method provided in the embodiment of the present application are based on the same inventive concept and have the same beneficial effects as the methods adopted, operated or implemented therein.

[0120] Embodiment 5

[0121] The embodiment of the present application further provides a computer-readable storage medium on which computer-readable instructions are stored. The computer-readable instructions can be executed by a processor to implement the motor control method of any implementation in the first embodiment.

[0122] Examples of the computer-readable storage medium may also include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other optical or magnetic storage media, which are not listed here one by one.

[0123] The computer-readable storage medium provided in the above-mentioned embodiments of the present application and the motor control method provided in the embodiments of the present application are based on the same inventive concept and have the same beneficial effects as the methods adopted, run or implemented by the application programs stored therein.

[0124] It should be noted that:

[0125] In the description provided herein, a large number of specific details are described. However, it is understood that the embodiments of the present application can be practiced without these specific details. In some instances, well-known methods, structures and techniques are not shown in detail so as not to obscure the understanding of this description.

[0126] Similarly, it should be understood that in order to streamline the present application and help understand one or more of the various inventive aspects, in the above description of the exemplary embodiments of the present application, the various features of the present application are sometimes grouped together into a single embodiment, figure, or description thereof. However, the disclosed method should not be interpreted as reflecting the following intention: the claimed application requires more features than the features clearly stated in each claim. More specifically, as reflected in the claims below, the inventive aspects are less than all the features of the single embodiment disclosed above. Therefore, the claims following the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself serves as a separate embodiment of the present application.

[0127] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and in addition they may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive, all features disclosed in this specification (including the accompanying claims, abstracts and drawings) and all processes or units of any method or device disclosed in this manner may be combined in any combination. Unless otherwise expressly stated, each feature disclosed in this specification (including the accompanying claims, abstracts and drawings) may be replaced by an alternative feature providing the same, equivalent or similar purpose.

[0128] In addition, those skilled in the art will appreciate that, although some embodiments described herein include certain features included in other embodiments but not other features, the combination of features of different embodiments is meant to be within the scope of the present application and form different embodiments. For example, in the claims below, any one of the claimed embodiments may be used in any combination.

[0129] The various component embodiments of the present application can be implemented in hardware, or in software modules running on one or more processors, or in a combination thereof. It should be understood by those skilled in the art that a microprocessor or digital signal processor (DSP) can be used in practice to implement some or all functions of some or all components in the creation device of the virtual machine according to the embodiment of the present application. The application can also be implemented as a device or device program (e.g., computer program and computer program product) for executing part or all of the methods described herein. Such a program implementing the present application can be stored on a computer-readable medium, or can have the form of one or more signals. Such a signal can be downloaded from an Internet website, or provided on a carrier signal, or provided in any other form.

[0130] It should be noted that the above embodiments illustrate the present application rather than limit the present application, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets should not be constructed as a limitation to the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present application may be implemented by means of hardware including several different elements and by means of a suitably programmed computer. In a unit claim that lists several devices, several of these devices may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names.

[0131] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A motor control method, characterized in that: include: Detect the load current of the motor; According to the load current of the motor being greater than a preset threshold, adjusting the modulation mode of controlling the motor according to the first modulation strategy; According to the load current of the motor being less than or equal to a preset threshold, the modulation mode for controlling the motor is adjusted according to the second modulation strategy.

2. The motor control method according to claim 1, characterized in that: The step of adjusting the modulation mode of controlling the motor according to the first modulation strategy based on the load current of the motor being greater than a preset threshold value includes: According to the load current of the motor being greater than a preset threshold, the modulation mode of controlling the motor is adjusted to the MC-GDPWM modulation mode.

3. The motor control method according to claim 1, characterized in that: The step of adjusting the modulation mode of controlling the motor according to the second modulation strategy based on the load current of the motor being less than or equal to a preset threshold value includes: According to the load current of the motor being less than or equal to a preset threshold, the current modulation ratio of the motor is obtained; The modulation mode of controlling the motor is adjusted according to whether the current modulation ratio is greater than the preset ratio.

4. The motor control method according to claim 3, characterized in that: The step of adjusting the modulation mode of controlling the motor according to whether the current modulation ratio is greater than a preset ratio includes: According to the current modulation ratio being greater than the preset ratio, the modulation mode of the control motor is adjusted to the DPWM modulation mode; According to the current modulation ratio being less than or equal to the preset ratio, the modulation mode of controlling the motor is adjusted to the SVM modulation mode.

5. The motor control method according to claim 4, characterized in that: The preset ratio is determined as follows: Acquire a plurality of preset candidate modulation ratios; Traversing the plurality of candidate modulation ratios, and selecting at least one target modulation ratio that meets a preset condition; Using the smallest target modulation ratio among the at least one target modulation ratio as a preset ratio; The pre-conditions are as follows: The current modulation ratio is greater than the target modulation ratio, and the motor phase current harmonics using the DPWM modulation method are smaller than the motor phase current harmonics using the SVM modulation method; The current modulation ratio is less than or equal to the target modulation ratio, and the motor phase current harmonics using the SVM modulation method are less than or equal to the motor phase current harmonics using the DPWM modulation method.

6. A motor control device, characterized in that: include: A detection module, used for detecting the load current of the motor; An adjustment module, configured to adjust a modulation mode of controlling the motor according to a first modulation strategy based on a load current of the motor being greater than a preset threshold; According to the load current of the motor being less than or equal to a preset threshold, the modulation mode for controlling the motor is adjusted according to the second modulation strategy.

7. The motor control device according to claim 6, characterized in that: The adjustment module is specifically used for: According to the load current of the motor being greater than a preset threshold, the modulation mode of controlling the motor is adjusted to the MC-GDPWM modulation mode.

8. A household appliance, characterized in that: A motor control method according to any one of claims 1 to 5 is adopted.

9. The household appliance according to claim 8, characterized in that: The household appliance is a clothes dryer, a washing machine or a washer-dryer.

10. A household appliance comprising: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the method according to any one of claims 1 to 5.

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