Carrier frequency control method, control device and air conditioner for power factor correction

Abstract

The application discloses a carrier frequency control method, a control device and an air conditioner for power factor correction, wherein the carrier frequency control method is a special carrier frequency control method used near the zero-crossing point of the variable carrier frequency control method; for the carrier frequency corresponding to the input voltage / input current near the zero-crossing point, the carrier frequency is limited to a fixed value or is increased with the decrease of the input voltage / input current, so that the input current of the PFC circuit near the zero-crossing point cannot follow the input voltage, the current harmonic of the PFC circuit is reduced, and the working stability of the PFC circuit is improved.

Description

Technical Field

[0001] This invention relates to the field of electronic circuit control technology, and in particular to a carrier frequency control method, control device, and air conditioner for power factor correction. Background Technology

[0002] Existing PFC (Power Factor Correction) control technology uses digital software and can employ a variable carrier frequency control method for power factor correction. The variable carrier frequency control method changes the carrier frequency according to the magnitude of the input voltage, with different carrier frequency values ​​under different input voltages. Although the variable carrier frequency control method reduces harmonics to some extent, it is prone to zero-crossing distortion at the zero-crossing point, that is, the input current is not zero when the input voltage is zero, which is equivalent to increasing harmonics and affecting the stability of the circuit near the zero-crossing point. Summary of the Invention

[0003] The following is an overview of the subject matter described in detail herein. This overview is not intended to limit the scope of the claims.

[0004] This invention provides a carrier frequency control method, control device, and air conditioner for power factor correction. When the input voltage or input current of the power factor correction circuit is too low, the carrier frequency is controlled to maintain a fixed value or increase, so that the input current at the zero-crossing point can follow the input voltage and reduce harmonics at the zero-crossing point.

[0005] An embodiment of the first aspect of the present invention provides a carrier frequency control method for power factor correction, applied to a power factor correction (PFC) circuit, the carrier frequency control method comprising:

[0006] Obtain the input voltage of the PFC circuit;

[0007] When the input voltage is greater than the set voltage, the carrier frequency of the PFC circuit is controlled to decrease as the input voltage decreases;

[0008] When the input voltage is less than the set voltage, the carrier frequency is set to a fixed value or the carrier frequency is controlled to increase as the input voltage decreases.

[0009] According to the first aspect of the present invention, the carrier frequency control method for power factor correction has at least the following beneficial effects: for the carrier frequency corresponding to the input voltage near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0010] In some embodiments, the second phase interval is a degradation interval. That is, the two endpoints of the second phase interval are the same and equal to the peak phase of the voltage phase, and the carrier frequency converges to a point in the second phase interval.

[0011] In some embodiments, controlling the carrier frequency to increase as the input voltage decreases includes:

[0012] The ratio of the set voltage to the input voltage is taken as the first ratio.

[0013] The carrier frequency is controlled to increase by the nth power of the first ratio, where n is greater than 1.

[0014] Since the input voltage is relatively small near the zero-crossing point, the input voltage is used as the denominator of the first ratio, so that the carrier frequency can increase as the input voltage decreases, thereby changing the phenomenon of the carrier frequency being too low near the zero-crossing point and ensuring the current harmonics near the zero-crossing point.

[0015] In some embodiments, when the frequency value obtained by increasing the carrier frequency by the nth power of the first ratio is greater than the maximum frequency threshold, the carrier frequency is set as the maximum frequency threshold. Since the input voltage approaches 0 near the zero crossing point, to avoid the carrier frequency multiplied by the first ratio becoming too large, a maximum value of the carrier frequency, i.e., the maximum frequency threshold, is limited. Carrier frequencies exceeding the maximum frequency threshold are all limited to the maximum frequency threshold to ensure the normal operation of the circuit.

[0016] A second aspect of the present invention provides a carrier frequency control method for power factor correction, applied to a power factor correction (PFC) circuit, the carrier frequency control method comprising:

[0017] Obtain the input current of the PFC circuit;

[0018] When the input current is greater than the set current, the carrier frequency of the PFC circuit is controlled to decrease as the input current decreases.

[0019] When the input current is less than the set current, the carrier frequency is set to a fixed value or the carrier frequency is controlled to increase as the input current decreases.

[0020] According to the second aspect of the present invention, the carrier frequency control method for power factor correction has at least the following beneficial effects: for the carrier frequency corresponding to the input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0021] In some embodiments, controlling the carrier frequency to increase as the input current decreases includes:

[0022] The ratio of the set current to the input current is used as the second ratio.

[0023] The carrier frequency is controlled to increase by the power of the second ratio, where m is greater than 1.

[0024] Since the input current is relatively small near the zero-crossing point, the input current is used as the denominator of the second ratio, so that the carrier frequency can increase as the input current decreases, thereby changing the phenomenon of the carrier frequency being too low near the zero-crossing point and ensuring the current harmonics near the zero-crossing point.

[0025] In some embodiments, when the frequency value obtained by increasing the carrier frequency by the m-th power of the second ratio is greater than the maximum frequency threshold, the carrier frequency is set as the maximum frequency threshold. Since the input current approaches 0 near the zero-crossing point, to avoid the multiplication of the carrier frequency and the second ratio becoming too large, a maximum value of the carrier frequency, i.e., the maximum frequency threshold, is limited. Carrier frequencies exceeding the maximum frequency threshold are all limited to the maximum frequency threshold to ensure the normal operation of the circuit.

[0026] A third aspect of the present invention provides a power factor correction carrier frequency control device, including at least one processor and a memory for communicatively connecting to the at least one processor; the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform a power factor correction carrier frequency control method as described in the first aspect above or to perform a power factor correction carrier frequency control method as described in the second aspect above.

[0027] According to the carrier frequency control device of the third aspect of the present invention, it has at least the following beneficial effects: by executing the above-described carrier frequency control method by the carrier frequency control device, for the carrier frequency corresponding to the input voltage / input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0028] A fourth aspect of the present invention provides a circuit board including the carrier frequency control device described in the third aspect above.

[0029] According to the fourth aspect of the present invention, the circuit board has at least the following beneficial effects: by integrating the above-mentioned carrier frequency control device on the circuit board, the circuit board has the function of the above-mentioned carrier frequency control device. For the carrier frequency corresponding to the input voltage / input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0030] A fifth aspect of the present invention provides an air conditioner, including the circuit board described in the fourth aspect above.

[0031] According to the fourth aspect of the present invention, the air conditioner has at least the following beneficial effects: by setting the above-mentioned circuit board in the air conditioner to control the air conditioner, the ripple current of the PFC circuit in the air conditioner at the zero crossing point can be controlled. That is, for the carrier frequency corresponding to the input voltage / input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0032] A fifth aspect of the present invention provides a computer-readable storage medium storing computer-executable instructions for causing a computer to perform the control method of the power factor correction circuit of the first aspect described above.

[0033] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the description, claims, and drawings. Attached Figure Description

[0034] Figure 1 This is a circuit diagram of a power factor correction circuit provided in an embodiment of the present invention;

[0035] Figure 2 This is another circuit diagram of the power factor correction circuit provided in the embodiment of the present invention;

[0036] Figure 3 This is a flowchart of the carrier frequency control method provided in the embodiments of the present invention;

[0037] Figure 4 This is a flowchart illustrating how the carrier frequency increases as the input voltage decreases, provided in an embodiment of the present invention.

[0038] Figure 5 This is a flowchart of the carrier frequency control method provided in the embodiments of the present invention;

[0039] Figure 6 This is a flowchart illustrating how the carrier frequency increases as the input current decreases, provided in an embodiment of the present invention.

[0040] Figure 7 This is a schematic diagram of the module connection relationship of the control device of the present invention. Detailed Implementation

[0041] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0042] This invention provides a carrier frequency control method, a carrier frequency control device, and an air conditioner for power factor correction. The carrier frequency control range is divided according to a set voltage or a set current. When the voltage or current is higher than the set voltage or current, the carrier frequency of the PFC circuit is controlled in a variable carrier frequency manner, so that the carrier frequency changes positively with the input voltage or input current. When the voltage or current is lower than the set voltage or current, the carrier frequency is set to a fixed value or changes negatively with the input voltage or input current, thereby improving the current harmonics near the zero crossing point and improving the working stability of the PFC circuit.

[0043] The embodiments of the present invention will be further described below with reference to the accompanying drawings.

[0044] This invention provides a control method for a power factor correction circuit, applied to a power factor correction (PFC) circuit. The circuit structure of this PFC circuit can be referred to... Figure 1 The system includes a DC input terminal, a boost module, a filter module, and a controller connected in sequence. The DC voltage at the DC input terminal is obtained by rectifying the AC input, and this DC voltage is the input voltage Uin of the PFC circuit. The DC current corresponding to the input voltage Uin is the current input current Iin of the PFC circuit. The DC input terminal is connected to the boost module, which is used for boosting the voltage. The boost module includes an inductor and a switching device. The inductor is connected in series with the positive terminal of the DC input terminal. One end of the switching device is connected to the inductor, and the other end is connected to the negative terminal of the DC input terminal. The controlled end of the switching device is connected to the enable pin of the controller. The filter module is connected in parallel with the switching device. The load ( Figure 1 (Not shown in the image) Connected in parallel across the filter module, the DC voltage input to the load is the current PFC circuit's output voltage Uo. It can be seen that the controller can achieve boost output and implement the PFC control process by controlling the switching devices to turn on and off.

[0045] It is understandable that the above PFC circuit may also include a diode, with the anode of the diode connected to the junction of the inductor and the switch, and the cathode of the diode connected to one end of the filter module. The filter module can be implemented using capacitors or other filter circuits. For ease of representation, Figure 1 The filter circuit is represented by a single capacitor.

[0046] The boost module in the PFC circuit described above can also adopt another circuit structure, see reference. Figure 2 The boost module consists of three parallel circuits, each including inductors and switches connected in series. One end of each inductor is connected to the positive terminal of the DC input, and the other end is connected to the negative terminal of the DC input via a switch. The controlled terminals of all three switches are connected to the enable pin of the controller. Each of the three branches of the boost module can also be equipped with a diode. The anode of the diode is connected to the junction of the inductor and switch, and the cathode is connected to one end of the filter module. Figure 2 This type of circuit can also achieve PFC control.

[0047] It is understood that the two PFC circuits described above are merely examples illustrating some circuit configurations that can implement the carrier frequency control method of the embodiments of the present invention. Various modifications, optimizations, and extensions made based on the above PFC circuits can also implement the control method of the embodiments of the present invention. To avoid excessive enumeration, they will not be elaborated here.

[0048] Based on the above PFC circuit, referring to Figure 3 The control methods include, but are not limited to, the following steps:

[0049] Step S100: Obtain the input voltage Uin of the PFC circuit;

[0050] Step S200: When the input voltage Uin is greater than the set voltage, the carrier frequency of the PFC circuit is controlled to decrease as the input voltage Uin decreases.

[0051] Step S300: When the input voltage Uin is less than the set voltage, the carrier frequency is set to a fixed value or the carrier frequency is controlled to increase as the input voltage Uin decreases.

[0052] The input voltage Uin of the PFC circuit is rectified from the AC mains power. The input voltage changes periodically. In order to ensure that the input current Iin of the PFC circuit follows the change of the input voltage Uin, a variable carrier frequency is usually used for control. Under the variable carrier frequency control method, the carrier frequency increases as the input voltage Uin increases and decreases as the input voltage Uin decreases. However, near the zero-crossing point of the input voltage Uin, since the input voltage Uin approaches 0, the carrier frequency also approaches 0, which causes the input current to fail to follow the input voltage near the zero-crossing point. This is equivalent to generating current harmonics, which affects the stability of the PFC circuit.

[0053] To mitigate current harmonics near the zero-crossing point, this embodiment of the invention divides the carrier frequency control range. Within the range where the input voltage Uin is low (below the set voltage Ux), the carrier frequency is adjusted to a fixed value or controlled to increase instead of decrease. Conversely, when the input voltage Uin is higher than the set voltage Ux, the carrier frequency is controlled using a conventional variable carrier frequency method. The set voltage Ux (a value greater than 0) can be set according to the actual performance of the PFC circuit.

[0054] Specifically, the formula for calculating the carrier frequency in the variable carrier frequency control method can be found in the following formula:

[0055]

[0056] Where ΔI is the ripple current of the PFC circuit, and L is the inductance of the inductor. From the above equation, it can be seen that the carrier frequency f varies with ΔI, L, Uin, and Uo, where... As a variable coefficient, it can be represented by the duty cycle D, so the above equation can be simplified to:

[0057]

[0058] According to the simplified formula, the carrier frequency f can be considered to be positively correlated with the input voltage Uin to a certain extent.

[0059] Based on the above PFC circuit, steps S100 to S300, and the variable carrier frequency calculation formula, the concept of the control method of the present invention will be explained below using two specific control methods.

[0060] Example 1: Carrier frequency control based on input voltage Uin:

[0061] The value of the carrier frequency f varies according to the variable carrier frequency calculation formula;

[0062] When the input voltage Uin is lower than the set voltage Ux, the PFC circuit controller outputs a fixed frequency value, so that the carrier frequency f no longer decreases. At this time, the actual ripple current value ΔI of the PFC circuit decreases as the input voltage Uin decreases, thereby reducing the current harmonics near the zero crossing point and realizing that the input current Iin follows the change of the input voltage Uin, avoiding the problem of distortion of the input current Iin near the zero crossing point.

[0063] Example 2: Carrier frequency control based on input voltage Uin:

[0064] The value of the carrier frequency f varies according to the variable carrier frequency calculation formula;

[0065] When the input voltage Uin is lower than the set voltage Ux, the carrier frequency f changes according to the following formula:

[0066]

[0067] Where n is greater than 1, and f is the variable carrier frequency calculation formula mentioned above. As can be seen from the above, the nth power of the ratio of the set voltage Ux to the input voltage Uin is used as the coefficient of the carrier frequency f. Since the input voltage Uin decreases at the zero-crossing point, the actual carrier frequency f′ output by the controller actually increases. That is, referring to... Figure 4 Step S300, which controls the carrier frequency to increase as the input voltage Uin decreases, includes:

[0068] Step S310: The ratio of the set voltage Ux to the input voltage Uin is taken as the first ratio.

[0069] Step S320: Control the carrier frequency to increase by the nth power of the first ratio, where n is greater than 1.

[0070] The first ratio is the ratio of the set voltage Ux to the input voltage Uin. Since the input voltage Uin approaches zero near the zero-crossing point, a maximum frequency threshold can be set to avoid the actual carrier frequency f′ being too large. When the calculated actual carrier frequency f′ is greater than the maximum frequency threshold, the actual carrier frequency f′ is directly set as the maximum frequency threshold, thus preventing the controller or switching device from being unable to keep up with the actual carrier frequency f′.

[0071] Example 2 also reduces current harmonics by changing the carrier frequency near the zero-crossing point, thus avoiding the problem of distortion of the input current Iin near the zero-crossing point.

[0072] This invention also provides a control method for a power factor correction circuit, applied to the aforementioned power factor correction (PFC) circuit. Since the input voltage Uin and input current Iin in the PFC circuit are positively correlated, steps S100 to S300 can actually be implemented based on the obtained input current Iin, i.e., referring to... Figure 5 The carrier frequency control method of this invention includes the following steps:

[0073] Step S400: Obtain the input current Iin of the PFC circuit;

[0074] Step S500: When the input current Iin is greater than the set current Ix, the carrier frequency of the PFC circuit is controlled to decrease as the input current Iin decreases.

[0075] Step S600: When the input current Iin is less than the set current Ix, the carrier frequency is set to a fixed value or the carrier frequency is controlled to increase as the input current Iin decreases.

[0076] Since the input current Iin is positively correlated with the input voltage Uin, steps S400 to S600 are similar to steps S100 to S300, respectively. Similarly, in order to improve the current harmonics near the zero crossing point, this embodiment of the invention divides the control range of the carrier frequency. In the range where the input current Iin is low, that is, when it is lower than the set current Ix, the carrier frequency is adjusted to a fixed value or the carrier frequency is controlled to increase instead of decrease. When the input current Iin is higher than the set current Ix, the carrier frequency is controlled in the conventional variable carrier frequency method.

[0077] It is worth noting that the set current Ix can be set to a value (greater than 0) based on the actual performance of the PFC circuit, or it can be set based on the ripple current ΔI of the PFC circuit. Since the input voltage Uin and the input current Iin in the PFC circuit are positively correlated, the variable carrier frequency calculation formula in this embodiment is the same as the variable carrier frequency calculation formula in the previous embodiment.

[0078] Based on the above PFC circuit, steps S400 to S600, and the variable carrier frequency calculation formula, the concept of the control method of the present invention will be explained below using two specific control methods.

[0079] Example 3: Carrier frequency control based on input current Iin:

[0080] The value of the carrier frequency f varies according to the variable carrier frequency calculation formula;

[0081] When the input current Iin is lower than the set current Ix, the PFC circuit controller outputs a fixed frequency value, so that the carrier frequency f no longer decreases. At this time, the actual ripple current value ΔI of the PFC circuit decreases as the input current Iin decreases, thereby reducing the current harmonics near the zero crossing point, realizing that the input current Iin follows the change of the input current Iin, and avoiding the problem of distortion of the input current Iin near the zero crossing point.

[0082] Example 4: Carrier frequency control based on input current Iin:

[0083] The value of the carrier frequency f varies according to the variable carrier frequency calculation formula;

[0084] When the input current Iin is lower than the set current Ix, the carrier frequency f changes according to the following formula:

[0085]

[0086] Where m is greater than 1, and f is the variable carrier frequency calculation formula mentioned above. As can be seen from the above, the m-th power of the ratio of current Ix to input current Iin is used as the coefficient of the carrier frequency f. Since the input current Iin decreases at the zero-crossing point, the actual carrier frequency f′ output by the controller actually increases. That is, referring to... Figure 6 Step S600, which controls the carrier frequency to increase as the input current Iin decreases, includes:

[0087] Step S610: The ratio of the set current Ix to the input current Iin is used as the second ratio.

[0088] Step S620: Control the carrier frequency to increase by the power of the second ratio, where m is greater than 1.

[0089] The second ratio is the ratio of the set current Ix to the input current Iin. Since the input current Iin approaches zero near the zero-crossing point, a maximum frequency threshold can also be set to avoid the actual carrier frequency f″ being too large. When the calculated actual carrier frequency f′ is greater than the maximum frequency threshold, the actual carrier frequency f″ is directly set as the maximum frequency threshold, thus preventing the control speed of the controller or switching device from being unable to keep up with the actual carrier frequency f″.

[0090] Example 4 also reduces current harmonics by changing the carrier frequency near the zero-crossing point, thus avoiding the problem of distortion of the input current Iin near the zero-crossing point.

[0091] As can be seen from the above four examples, the embodiments of the present invention perform special control on the carrier frequency near the zero crossing point, so that the carrier frequency no longer decreases with the decrease of the input voltage Uin or the input current Iin, but is set to a fixed value or increases with the decrease of the input voltage Uin or the input current Iin, thereby reducing the current harmonics near the zero crossing point and improving the stability of the PFC circuit.

[0092] This invention also provides a power factor correction carrier frequency control device, including at least one processor and a memory for communicatively connecting to the at least one processor; the memory stores instructions executable by the at least one processor, which are executed by the at least one processor to enable the at least one processor to execute any one of the power factor correction carrier frequency control methods in the foregoing two embodiments.

[0093] Reference Figure 7 For example, the control processor 1001 and memory 1002 in the control device 1000 can be connected via a bus. The memory 1002, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, the memory 1002 may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, the memory 1002 may optionally include memory remotely located relative to the control processor 1001, and these remote memories can be connected to the control device 1000 via a network. Examples of such networks include, but are not limited to, the Internet, corporate intranets, local area networks, mobile communication networks, and combinations thereof.

[0094] Those skilled in the art will understand that Figure 7 The device structure shown does not constitute a limitation on the control device 1000, and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0095] In this embodiment of the invention, the carrier frequency control method described above is executed by a carrier frequency control device. For the carrier frequency corresponding to the input voltage / input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, the current harmonics of the PFC circuit can be reduced, and the working stability of the PFC circuit can be improved.

[0096] This invention also provides a circuit board including the aforementioned carrier frequency control device. By integrating the carrier frequency control device on the circuit board, for the carrier frequency corresponding to the input voltage / input current near the zero crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / input current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero crossing point can be improved, reducing the current harmonics of the PFC circuit and improving the operating stability of the PFC circuit.

[0097] This invention also provides an air conditioner, including the aforementioned circuit board. By incorporating the circuit board into the air conditioner to control it, the ripple current of the PFC circuit at the zero-crossing point can be controlled. Specifically, for the carrier frequency corresponding to the input voltage / current near the zero-crossing point, by limiting the carrier frequency to a fixed value or increasing the carrier frequency as the input voltage / current decreases, the situation where the input current of the PFC circuit cannot follow the input voltage near the zero-crossing point can be improved, reducing the current harmonics of the PFC circuit and improving its operational stability.

[0098] A fifth aspect of the present invention provides a computer-readable storage medium storing computer-executable instructions that are executed by one or more control processors, for example, by... Figure 7 One of the control processors 1001 executes the method, which enables the one or more control processors to perform the overcurrent protection method in the above method embodiment, for example, to perform the method described above. Figure 3 Method steps S100 to S300 Figure 4 Method steps S310 to S320 Figure 5 Method steps S400 to S600 and Figure 6 Method steps S610 to S620.

[0099] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.

[0100] It will be understood by those skilled in the art that all or some of the steps and systems in the methods disclosed above can be implemented as software, firmware, hardware, and suitable combinations thereof. Some or all of the physical components can be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit. Such software can be distributed on a computer-readable medium, which can include computer storage media (or non-transitory media) and communication media (or transient media). As is known to those skilled in the art, the term computer storage media includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information (such as computer-readable instructions, data structures, program modules, or other data). Computer storage media includes, but is not limited to, RAM, ROM, EEPROM, flash memory or other memory technologies, CD-ROM, digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, as is known to those skilled in the art, communication media typically contain computer-readable instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0101] The above is a detailed description of the preferred embodiments of this application. However, this application is not limited to the above embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of this application. All such equivalent modifications or substitutions are included within the scope defined by the claims of this application.

Claims

1. A carrier frequency control method for power factor correction, applied to a power factor correction (PFC) circuit, the carrier frequency control method comprising: Obtain the input voltage of the PFC circuit; When the input voltage is greater than the set voltage, the carrier frequency of the PFC circuit is controlled to decrease as the input voltage decreases; When the input voltage is less than the set voltage, the carrier frequency is controlled to increase as the input voltage decreases; The control of the carrier frequency to increase as the input voltage decreases includes: The ratio of the set voltage to the input voltage is taken as the first ratio. Output the actual carrier frequency, which is equal to the product of the carrier frequency and the first ratio raised to the power of n, where n is greater than 1.

2. The carrier frequency control method according to claim 1, characterized in that, When the frequency value obtained by increasing the carrier frequency by the nth power of the first ratio is greater than the maximum frequency threshold, the carrier frequency is set as the maximum frequency threshold.

3. A carrier frequency control method for power factor correction, applied to a power factor correction (PFC) circuit, the carrier frequency control method comprising: Obtain the input current of the PFC circuit; When the input current is greater than the set current, the carrier frequency of the PFC circuit is controlled to decrease as the input current decreases. When the input current is less than the set current, the carrier frequency is controlled to increase as the input current decreases; The control of the carrier frequency to increase as the input current decreases includes: The ratio of the set current to the input current is used as the second ratio. Output the actual carrier frequency, which is equal to the product of the carrier frequency and the second ratio raised to the power of m, where m is greater than 1.

4. The carrier frequency control method according to claim 3, characterized in that, When the frequency value obtained by increasing the carrier frequency by the second ratio to the power of m is greater than the maximum frequency threshold, the carrier frequency is set as the maximum frequency threshold.

5. A carrier frequency control device for power factor correction, characterized in that, The device includes at least one processor and a memory for communicatively connecting to the at least one processor; the memory stores instructions executable by the at least one processor, the instructions being executed by the at least one processor to enable the at least one processor to perform the carrier frequency control method as described in any one of claims 1 to 2 or to perform the carrier frequency control method as described in any one of claims 3 to 4.

6. A circuit board, characterized in that, Includes the carrier frequency control device as described in claim 5.

7. An air conditioner, characterized in that, Includes the circuit board as described in claim 6.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions for causing a computer to perform a power factor correction carrier frequency control method as described in any one of claims 1 to 2 or to perform a carrier frequency control method as described in any one of claims 3 to 4.

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