Air conditioner and control method and device thereof

Abstract

The invention discloses an air conditioner and a control method and device thereof.The control method includes the steps that input alternating voltage is obtained, and the magnitude of the alternating voltage and the magnitude of rated voltage are judged; when the AC voltage is greater than or less than the rated voltage, determining a preset voltage interval where the AC voltage is located, and obtaining a target bus voltage corresponding to the preset voltage interval; and the actual bus voltage of the air conditioner is adjusted to the target bus voltage, and a motor in the air conditioner is driven to operate according to the target bus voltage. The condition that the air conditioner is out of control when the current alternating voltage suddenly changes can be effectively relieved.

Description

Technical Field

[0001] This application relates to the field of electronic technologies, and particularly to an air conditioner and its control method and device. Background Art

[0002] A variable-frequency air conditioner generally includes a rectification module, an inversion module, a motor, etc. The rectification module is connected to a three-phase power supply, converts the input alternating current into direct current to form a bus voltage, which serves as the power supply for the inversion module. The inversion module then converts the direct current back into alternating current to drive the motor to operate.

[0003] During this process, the rectified bus voltage is directly inverted to control the motor. If the alternating voltage input by the three-phase power supply suddenly changes, it will directly cause a rapid fluctuation of the bus voltage, and it is very easy to occur that the fluctuation exceeds the controllable range due to the inability of the motor control loop to respond in time, resulting in the situation that the air conditioner gets out of control.

[0004] Therefore, the current technology still needs to be improved. Summary of the Invention

[0005] This application provides an air conditioner and its control method and device, which can effectively alleviate the situation that the air conditioner gets out of control when the alternating voltage suddenly changes currently.

[0006] This application provides a control method for an air conditioner, including:

[0007] Obtain the input alternating voltage and judge the magnitude relationship between the alternating voltage and the rated voltage;

[0008] When the alternating voltage is greater than or less than the rated voltage, determine the preset voltage range where the alternating voltage is located, and obtain the target bus voltage corresponding to the preset voltage range;

[0009] Adjust the actual bus voltage of the air conditioner to the target bus voltage, and drive the motor in the air conditioner to operate according to the target bus voltage.

[0010] In the control method of the air conditioner in some embodiments, after the step of obtaining the input alternating voltage of the air conditioner and judging the magnitude relationship between the alternating voltage and the rated voltage, it further includes:

[0011] When the alternating voltage is greater than or less than the rated voltage, determine the preset voltage range where the alternating voltage is located, and obtain the target operating frequency corresponding to the preset voltage range;

[0012] Adjust the actual operating frequency of the motor to the target operating frequency, and drive the motor to operate according to the target operating frequency.

[0013] In the control method of the air conditioner in some embodiments, the step of judging the magnitude relationship between the alternating voltage and the rated voltage includes:

[0014] Obtain the peak voltage of the AC voltage within a cycle according to the cycle of the input power supply of the air conditioner, and compare the peak voltage with the rated voltage;

[0015] If the peak voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the peak voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

[0016] In the control method of the air conditioner in some embodiments, the steps of judging the magnitude of the AC voltage and the rated voltage include:

[0017] Obtain the effective voltage of the AC voltage within a cycle according to the cycle of the input power supply of the air conditioner, and compare the effective voltage with the rated voltage;

[0018] If the effective voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the effective voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

[0019] In the control method of the air conditioner in some embodiments, the steps of judging the magnitude of the AC voltage and the rated voltage include:

[0020] Obtain the direct-axis voltage according to the AC voltage, and compare the direct-axis voltage with the rated voltage;

[0021] If the direct-axis voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the direct-axis voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

[0022] In the control method of the air conditioner in some embodiments, the control method of the air conditioner further includes:

[0023] Pre-store the mapping relationship between the preset voltage range, the target bus voltage and the target operating frequency.

[0024] In the control method of the air conditioner in some embodiments, after the step of obtaining the target operating frequency corresponding to the preset voltage range:

[0025] Judge whether the actual operating frequency of the motor is consistent with the target operating frequency;

[0026] If so, continue to drive the motor to operate according to the actual operating frequency.

[0027] The embodiment of the present application also provides a control device for an air conditioner, and the control device includes:

[0028] A detection module, and the detection module is used to detect the input AC voltage;

[0029] A judgment module, which is connected to the detection module; the judgment module is used to compare the AC voltage with the rated voltage, and when the AC voltage is greater than or less than the rated voltage, determine the preset voltage range where the AC voltage is located, and output the corresponding target bus voltage according to the preset voltage range.

[0030] A control module, which is connected to the judgment module; the control module is used to adjust the actual bus voltage of the air conditioner to the target bus voltage, and drive the motor in the air conditioner to operate according to the target bus voltage.

[0031] In the control device of the air conditioner in some embodiments, the judgment module is further used to determine the preset voltage range where the AC voltage is located when the AC voltage is greater than or less than the rated voltage, and output the corresponding target operating frequency according to the preset voltage range.

[0032] The control module is further used to adjust the actual operating frequency of the motor to the target operating frequency, and drive the motor to operate according to the target operating frequency.

[0033] An embodiment of the present application also provides an air conditioner, which includes a motor and the above control device.

[0034] An air conditioner, its control method and device provided by the present application, by obtaining the AC voltage input to the air conditioner, comparing the AC voltage with the rated voltage, determining the preset voltage range where the AC voltage is located when the AC voltage is greater than or less than the rated voltage, and obtaining the target bus voltage corresponding to the preset voltage range, so as to adjust the actual bus voltage to the target bus voltage. Thereafter, the motor is driven to operate according to the target bus voltage, thereby ensuring that when the input AC voltage changes, the bus voltage can be adjusted in time to alleviate the problem of out-of-control of the air conditioner when the input AC voltage changes. Description of the Drawings

[0035] The following will make the technical solutions and other beneficial effects of the present application obvious by describing the specific embodiments of the present application in detail with reference to the drawings.

[0036] Figure 1 It is the first flow diagram of the control method of the air conditioner provided by the embodiment of the present application.

[0037] Figure 2 It is the second flow diagram of the control method of the air conditioner provided by the embodiment of the present application.

[0038] Figure 3 It is the first flow diagram of step 100 in the control method of the air conditioner provided by the embodiment of the present application.

[0039] Figure 4It is the second flow schematic diagram of step 100 in the control method of the air conditioner provided by the embodiment of the present application.

[0040] Figure 5 It is the third flow schematic diagram of step 100 in the control method of the air conditioner provided by the embodiment of the present application.

[0041] Figure 6 It is the curve schematic diagram between the preset voltage range and the target bus voltage and the target operating frequency in the control method of the air conditioner provided by the embodiment of the present application.

[0042] Figure 7 It is the third flow schematic diagram in the control method of the air conditioner provided by the embodiment of the present application.

[0043] Figure 8 It is the structural block diagram of the control device of the air conditioner provided by the embodiment of the present application. Detailed implementation manners

[0044] Next, the technical solutions in the embodiments of the present application will be clearly and completely described with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments of the present application, all other embodiments obtained by those skilled in the art without creative efforts belong to the scope of protection of the present application.

[0045] In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the present application, "a plurality" means two or more, unless otherwise specifically defined.

[0046] Please refer to Figure 1 , the embodiment of the present application provides a control method for an air conditioner, and the control method includes:

[0047] 100. Obtain the input AC voltage and judge the magnitude of the AC voltage and the rated voltage;

[0048] 200. When the AC voltage is greater than or less than the rated voltage, determine the preset voltage range where the AC voltage is located, and obtain the target bus voltage corresponding to the preset voltage range;

[0049] 300. Adjust the actual bus voltage of the air conditioner to the target bus voltage, and drive the motor in the air conditioner to operate according to the target bus voltage.

[0050] In this embodiment, the AC voltage input by the air conditioner is obtained, and the AC voltage is compared with the rated voltage to determine whether the input AC voltage fluctuates. Among them, the rated voltage refers to the voltage required for the air conditioner to operate normally, and the rated voltage may vary according to the grid standards in different regions. When the AC voltage is greater than or less than the rated voltage, it indicates that the input AC voltage fluctuates. Then, the preset voltage range where the AC voltage is located is determined, and the target bus voltage corresponding to this preset voltage range is obtained, so as to adjust the actual bus voltage to the target bus voltage. Among them, the preset voltage range is a voltage range segment divided according to the magnitude of the AC voltage, so as to determine which voltage range segment the AC voltage is located in after obtaining the actual AC voltage. Thereafter, the motor is driven to operate according to the target bus voltage, thereby ensuring that when the input AC voltage changes, the bus voltage can be adjusted in time to alleviate the problem of out-of-control of the air conditioner when the input AC voltage changes.

[0051] Please refer to Figure 2 , in some embodiments, after step 100, it further includes:

[0052] 400. When the AC voltage is greater than or less than the rated voltage, determine the preset voltage range where the AC voltage is located, and obtain the target operating frequency corresponding to the preset voltage range;

[0053] 500. Adjust the actual operating frequency of the motor to the target operating frequency, and drive the motor to operate according to the target operating frequency.

[0054] When the input AC voltage changes, while adjusting the bus voltage, the operating frequency of the motor can also be adjusted accordingly. To ensure the stability of the motor operation, at different AC voltages, the corresponding operating frequencies are adapted according to debugging and stored to form a mapping relationship between the AC voltage and the operating frequency. In actual application, the preset voltage range where the AC voltage is located can be determined according to this mapping relationship, the target operating frequency corresponding to the preset voltage range is obtained, the actual operating frequency of the motor is adjusted to the target operating frequency according to this target operating frequency, and then the motor is driven to operate according to this target operating frequency, thereby improving the reliability of the motor control and avoiding the out-of-control situation of the air conditioner when the input AC voltage changes.

[0055] Please refer to Figure 3 , in some embodiments, step 100 includes:

[0056] 110. According to the period of the input power supply of the air conditioner, obtain the peak voltage of the AC voltage within the period, and compare the peak voltage with the rated voltage;

[0057] 120. If the peak voltage is greater than the rated voltage, then the AC voltage is greater than the rated voltage; if the peak voltage is less than the rated voltage, then the AC voltage is less than the rated voltage.

[0058] After obtaining the AC voltage, according to the period of the input power supply of the air conditioner, obtain the peak voltage of the AC voltage within the period, and compare this peak voltage with the rated voltage of the input power supply. If this peak voltage is greater than this rated voltage, it indicates that the AC voltage is greater than the rated voltage; similarly, if this peak voltage is less than this rated voltage, it indicates that the AC voltage is less than the rated voltage, thereby realizing the comparison of the magnitudes of the AC voltage and the rated voltage.

[0059] Please refer to Figure 4 , in some other embodiments, step 100 includes:

[0060] 101. According to the period of the input power supply of the air conditioner, obtain the effective voltage of the AC voltage within the period, and compare the effective voltage with the rated voltage;

[0061] 102. If the effective voltage is greater than the rated voltage, then the AC voltage is greater than the rated voltage; if the effective voltage is less than the rated voltage, then the AC voltage is less than the rated voltage.

[0062] After obtaining the AC voltage, it is also possible to obtain the effective voltage of this AC voltage within the period, and compare the effective voltage with the rated voltage. If this effective voltage is greater than the rated voltage, it indicates that the AC voltage is greater than the rated voltage; similarly, if this effective voltage is less than the rated voltage, it indicates that the AC voltage is less than the rated voltage, thereby realizing the comparison of the magnitudes of the AC voltage and the rated voltage.

[0063] Please refer to Figure 5 , in yet another embodiment, step 100 includes:

[0064] 111. Obtain the direct-axis voltage according to the AC voltage, and compare the direct-axis voltage with the rated voltage;

[0065] 112. If the direct-axis voltage is greater than the rated voltage, then the AC voltage is greater than the rated voltage; if the direct-axis voltage is less than the rated voltage, then the AC voltage is less than the rated voltage.

[0066] In this embodiment, after obtaining the AC voltage, obtain the direct-axis voltage according to the AC voltage, and compare the direct-axis voltage with the rated voltage. If the direct-axis voltage is greater than the rated voltage, it indicates that the AC voltage is greater than the rated voltage; if the direct-axis voltage is less than the rated voltage, it indicates that the AC voltage is less than the rated voltage. In the comparison process of this embodiment, there is no need to refer to the period of the input power supply. Compared with the above-mentioned peak method and effective value method for comparing the magnitudes of the AC voltage and the rated voltage, the real-time performance is better, which is beneficial to improving the response speed to the change of the AC voltage and ensuring the reliability of the motor control.

[0067] Among them, the control method of the air conditioner further includes: pre-storing the mapping relationship between the preset voltage range, the target bus voltage, and the target operating frequency. To ensure the stability of the motor operation, at different AC voltages, the corresponding bus voltage and operating frequency are adjusted according to debugging to form the mapping relationship between the AC voltage, the bus voltage, and the operating frequency for storage. Different AC voltage ranges in this mapping relationship are used as the preset voltage ranges, and the bus voltage and operating frequency corresponding to different AC voltages are used as the target bus voltage and the target operating frequency, so as to facilitate the subsequent timely adjustment of the motor's bus voltage and operating frequency.

[0068] Please refer to Figure 6 , Figure 6 In, the abscissa AC voltage, i.e., the AC voltage, and the ordinate Vbus, i.e., the bus voltage, correspond to the per-unit value Pu. There are 7 preset voltage ranges set, and the voltages of each preset voltage range are 0Vac - 0.4Vac, 0.4Vac - 0.6Vac, 0.6Vac - 0.8Vac, 0.8Vac - 0.9Vac, 0.9Vac - 1.1Vac, 1.1Vac - 1.2Vac, 1.2Vac - 1.4Vac respectively, where Vac is the rated voltage. The target bus voltages corresponding to each preset voltage range are 0, 0.4Vbus, 0.6Vbus, 0.8Vbus, 1.0Vbus, 1.1Vbus, 1.2Vbus in sequence, where Vbus is the bus voltage adapted under the rated voltage. The target operating frequencies corresponding to each preset voltage range are 0.0F, 0.2F, 0.5F, 0.7F, 1.0F, 1.0F, 1.0F in sequence, where F is the operating frequency adapted under the rated voltage. When the obtained AC voltage is 1.2 to 1.4 times the rated voltage, the corresponding target bus voltage is adjusted to 1.2Vbus of the original, and the corresponding target operating frequency is 1.0F.

[0069] Please refer to Figure 7 , as an embodiment, after step 400, it further includes:

[0070] 600. Determine whether the actual operating frequency of the motor is consistent with the target operating frequency;

[0071] 700. If so, continue to drive the motor to operate according to the actual operating frequency.

[0072] When the AC voltage fluctuates, determine the preset voltage range where the AC voltage is located, and obtain the corresponding target operating frequency according to this preset voltage range. Then, compare the actual operating frequency of the motor with the target operating frequency. If the actual operating frequency is the same as the target operating frequency, continue to drive the motor according to this actual operating frequency without adjusting the operating frequency of the motor. If the actual operating frequency is different from the target operating frequency, adjust the actual operating frequency to the target operating frequency to drive the motor. This can avoid repeated adjustments and simplify the control process of the air conditioner.

[0073] Please refer to Figure 8 , Embodiment of the present application also provides a control device 10 for an air conditioner. The control device 10 for the air conditioner includes a detection module 11, a judgment module 12, and a control module 13 that are connected in sequence. The detection module 11 is used to detect the input AC voltage. The judgment module 12 is used to compare the AC voltage with the rated voltage, and when the AC voltage is greater than or less than the rated voltage, determine the preset voltage range where the AC voltage is located, and output the corresponding target bus voltage according to the preset voltage range. The control module 13 is used to adjust the actual bus voltage of the air conditioner to the target bus voltage and drive the motor 20 in the air conditioner according to the target bus voltage.

[0074] In this embodiment, by obtaining the AC voltage input to the air conditioner, the judgment module 12 compares the AC voltage with the rated voltage to determine whether the input AC voltage fluctuates. When the AC voltage is greater than or less than the rated voltage, it indicates that the input AC voltage fluctuates, and then determine the preset voltage range where the AC voltage is located, and obtain the target bus voltage corresponding to this preset voltage range. The control module 13 adjusts the actual bus voltage to the target bus voltage to drive the motor 20 according to the target bus voltage, thereby ensuring that when the input AC voltage changes, the bus voltage can be adjusted in time to alleviate the problem of out-of-control caused by the change of the input AC voltage of the air conditioner.

[0075] In some embodiments, the judgment module 12 is further used to determine the preset voltage range where the AC voltage is located according to when the AC voltage is greater than or less than the rated voltage, and output the corresponding target operating frequency according to the preset voltage range. The control module 13 is further used to adjust the actual operating frequency of the motor 20 to the target operating frequency and drive the motor 20 according to the target operating frequency.

[0076] When the input AC voltage changes, while adjusting the bus voltage, the operating frequency of the motor 20 can also be adjusted accordingly. Correspondingly, the judgment module 12 obtains the target operating frequency corresponding to the preset voltage range according to the preset voltage range where the AC voltage is located. The control module 13 adjusts the actual operating frequency of the motor 20 to the target operating frequency according to the target operating frequency, and then drives the motor 20 to operate according to the target operating frequency, thereby improving the reliability of the control of the motor 20 and avoiding the out-of-control situation of the air conditioner when the input AC voltage changes.

[0077] The embodiment of the present application also provides an air conditioner, which includes the control device of the air conditioner described above. Since the control device has been described in detail above, it will not be repeated here.

[0078] In the above embodiments, the descriptions of the various embodiments have their own focuses. For the parts not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0079] The control method of the air conditioner provided by the embodiments of the present application has been introduced in detail above. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the technical solution and its core idea of the present application; those of ordinary skill in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or perform equivalent replacements on some of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A method for controlling an air conditioner, characterized in that: include: Obtaining an input AC voltage, and determining the magnitude of the AC voltage and a rated voltage; When the AC voltage is greater than or less than the rated voltage, determining a preset voltage interval in which the AC voltage is located, and obtaining a target bus voltage corresponding to the preset voltage interval; The actual bus voltage of the air conditioner is adjusted to the target bus voltage, and the motor in the air conditioner is driven to operate according to the target bus voltage.

2. The air conditioner control method according to claim 1, characterized in that: After the step of obtaining the AC voltage inputted by the air conditioner and determining the magnitude of the AC voltage and the rated voltage, the method further comprises: When the AC voltage is greater than or less than the rated voltage, determining a preset voltage interval in which the AC voltage is located, and obtaining a target operating frequency corresponding to the preset voltage interval; The actual operating frequency of the motor is adjusted to the target operating frequency, and the motor is driven to operate according to the target operating frequency.

3. The air conditioner control method according to claim 1 or 2, characterized in that: The step of determining the magnitude of the AC voltage and the rated voltage comprises: According to the cycle of the input power supply of the air conditioner, obtaining the peak voltage of the AC voltage within the cycle, and comparing the peak voltage with the rated voltage; If the peak voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the peak voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

4. The air conditioner control method according to claim 1 or 2, characterized in that: The step of determining the magnitude of the AC voltage and the rated voltage comprises: According to the cycle of the input power supply of the air conditioner, obtaining the effective voltage of the AC voltage within the cycle, and comparing the effective voltage with the rated voltage; If the effective voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the effective voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

5. The air conditioner control method according to claim 1 or 2, characterized in that: The step of determining the magnitude of the AC voltage and the rated voltage comprises: Acquire a direct-axis voltage according to the AC voltage, and compare the direct-axis voltage with the rated voltage; If the direct-axis voltage is greater than the rated voltage, the AC voltage is greater than the rated voltage; if the direct-axis voltage is less than the rated voltage, the AC voltage is less than the rated voltage.

6. The air conditioner control method according to claim 2, characterized in that: The control method of the air conditioner also includes: The mapping relationship between the preset voltage range and the target bus voltage and the target operating frequency is stored in advance.

7. The air conditioner control method according to claim 2, characterized in that: After the step of obtaining the target operating frequency corresponding to the preset voltage interval: Determining whether the actual operating frequency of the motor is consistent with the target operating frequency; If so, continue to drive the motor to operate according to the actual operating frequency.

8. A control device for an air conditioner, characterized in that: The control device comprises: A detection module, wherein the detection module is used to detect an input AC voltage; A judgment module, the judgment module is connected to the detection module; the judgment module is used to compare the AC voltage with the rated voltage, and when the AC voltage is greater than or less than the rated voltage, determine the preset voltage interval in which the AC voltage is located, and output the corresponding target bus voltage according to the preset voltage interval; A control module is connected to the judgment module; the control module is used to adjust the actual bus voltage of the air conditioner to the target bus voltage, and drive the motor in the air conditioner to operate according to the target bus voltage.

9. The control device for an air conditioner according to claim 8, characterized in that: The judgment module is further used to determine the preset voltage interval of the AC voltage when the AC voltage is greater than or less than the rated voltage, and output the corresponding target operating frequency according to the preset voltage interval; The control module is further used to adjust the actual operating frequency of the motor to the target operating frequency, and drive the motor to operate according to the target operating frequency.

10. An air conditioner, characterized in that: The air conditioner comprises a motor and a control device as claimed in claim 8 or 9.

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