Harmonic current control method, PFC (Power Factor Correction) controller, equipment electric control device and household appliance

Abstract

The invention discloses a harmonic current control method, a PFC (Power Factor Correction) controller, an equipment electric control device and a household appliance, the method is applied to the equipment electric control device, the equipment electric control device comprises a PFC circuit, and the method comprises the following steps: determining working parameters of the PFC circuit under the condition that the PFC circuit is turned on; a compensation coefficient is determined according to the working parameters, a high-frequency harmonic signal is injected into the input current through the PFC circuit according to the compensation coefficient, and the high-frequency harmonic signal is used for restraining the waveform peak value of the input current. According to the method, heating of the bus capacitor in the equipment electric control device can be further reduced under the condition that the equipment electric control device meets the product harmonic authentication standard requirement, so that the reliability of the capacitor can be further improved, and the service life of the capacitor can be further prolonged.

Description

Technical Field

[0001] The present invention relates to the field of circuit control, and in particular to a harmonic current control method and a PFC controller, an equipment electric control device, and a household appliance. Background Art

[0002] In an electric control device with a PFC (Power Factor Correction) circuit, the heating problem of the bus capacitor has always been one of the pain points that affect the life of the capacitor. In this regard, the Chinese invention patent: Operation control method and system, compressor and air conditioner (patent number: CN111256275A) proposes a high-frequency harmonic injection scheme, which controls the PFC circuit to inject high-frequency harmonics into the AC input current input to the bus, and uses the superposition effect of high-frequency harmonics to flatten the peak of the input current waveform, so that the fundamental wave of the AC current input to the bus is reduced in amplitude under the superposition of high-frequency harmonics. Therefore, the bus capacitor no longer needs to be strongly charged and discharged to maintain current stability, so the heat generated by the bus capacitor can be reduced. However, since current harmonics will pollute the power grid, all types of electric control devices with PFC circuits must pass the product harmonic certification standards before they can be listed. Therefore, in actual application, this scheme usually uses high-frequency harmonics with smaller amplitudes to reduce the fundamental amplitude of the AC current input to the bus to meet the requirements of the product harmonic certification standards. However, the reduction of the peak value of the fundamental amplitude by the high-frequency harmonics with smaller amplitudes is also smaller, and the effect of reducing the heat generated by the bus capacitor is not obvious, resulting in poor effect of this solution in improving the reliability of the bus capacitor. Summary of the invention

[0003] The present invention aims to solve one of the technical problems in the related art to at least a certain extent. To this end, the first purpose of the present invention is to propose a harmonic current control method, by determining the working parameters of the PFC circuit when the PFC circuit is turned on, then determining the compensation coefficient based on the working parameters, and then injecting a high-frequency harmonic signal into the input current through the PFC circuit according to the compensation coefficient, thereby realizing the function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit, thereby ensuring that the equipment electronic control device meets the product harmonic certification standard requirements; and further reducing the heating of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0004] A second object of the present invention is to provide a computer-readable storage medium.

[0005] The third objective of the present invention is to provide a PFC controller.

[0006] A fourth objective of the present invention is to provide an electronic control device for equipment.

[0007] A fifth objective of the present invention is to provide a household appliance.

[0008] To achieve the above-mentioned purpose, a first aspect of the present invention proposes a harmonic current control method, which is applied to an equipment electronic control device, wherein the equipment electronic control device includes a PFC circuit, and the method includes: when the PFC circuit is turned on, determining the operating parameters of the PFC circuit; determining a compensation coefficient according to the operating parameters, and according to the compensation coefficient, injecting a high-frequency harmonic signal into the input current through the PFC circuit, wherein the high-frequency harmonic signal is used to suppress the waveform peak of the input current.

[0009] According to the harmonic current control method of the embodiment of the present invention, when the PFC circuit is turned on, the operating parameters of the PFC circuit are first determined, and then the compensation coefficient is determined based on the operating parameters. Then, according to the compensation coefficient, high-frequency harmonics are injected into the input current through the PFC circuit for control. The function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit is realized, thereby ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standard; and further reducing the heat generation of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0010] According to an embodiment of the present invention, the operating parameter includes at least one of a power factor, an input current and load information of the PFC circuit.

[0011] According to an embodiment of the present invention, when the load of the PFC circuit is a compressor, the load information includes the compressor frequency.

[0012] According to an embodiment of the present invention, when the operating parameter is the power factor, the power factor is determined according to the maximum power and input power of the PFC circuit.

[0013] According to one embodiment of the present invention, a compensation coefficient is determined according to an operating parameter, including: when a power coefficient is greater than a first preset value, determining a first target value as the compensation coefficient; when the power coefficient is less than or equal to a second preset value, determining a second target value as the compensation coefficient, wherein the second preset value is less than the first preset value, and the second target value is less than the first target value; when the power coefficient is less than or equal to the first preset value and greater than the second preset value, determining the compensation coefficient according to the power coefficient and the second target value.

[0014] According to an embodiment of the present invention, before the PFC circuit is turned on, the method further includes: acquiring an input current of the PFC circuit; and determining that the PFC circuit is turned on when the input current of the PFC circuit is greater than or equal to a preset current threshold.

[0015] According to an embodiment of the present invention, when the input current of the PFC circuit is less than a preset current threshold, the method further includes: determining that the compensation coefficient is zero.

[0016] To achieve the above-mentioned purpose, a second aspect of the present invention provides a computer-readable storage medium on which a harmonic current control program is stored. When the harmonic current control program is executed by a processor, the above-mentioned harmonic current control method is implemented.

[0017] According to the computer-readable storage medium of an embodiment of the present invention, through the aforementioned harmonic current control method, the heat generated by the bus capacitor in the equipment electronic control device can be further reduced while ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standards, thereby effectively improving the reliability and service life of the capacitor.

[0018] To achieve the above objectives, a third aspect of the present invention proposes a PFC controller, comprising: a memory, a processor, and a harmonic current control program stored in the memory and executable on the processor. When the processor executes the program, the aforementioned harmonic current control method is implemented.

[0019] According to the PFC controller of the embodiment of the present invention, through the aforementioned harmonic current control method, it is possible to further reduce the heat generated by the bus capacitor in the equipment electronic control device while ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standard, thereby effectively improving the reliability and service life of the capacitor.

[0020] To achieve the above-mentioned purpose, an embodiment of a fourth aspect of the present invention proposes an electronic control device for an equipment, comprising: a PFC circuit; and a controller, configured to determine the operating parameters of the PFC circuit when the PFC circuit is turned on, and determine a compensation coefficient based on the operating parameters, and inject a high-frequency harmonic signal into the input current through the PFC circuit based on the compensation coefficient, wherein the high-frequency harmonic signal is used to suppress the waveform peak of the input current.

[0021] According to the equipment electronic control device of the embodiment of the present invention, when the PFC circuit is turned on, the controller determines the operating parameters of the PFC circuit, then determines the compensation coefficient based on the operating parameters, and according to the compensation coefficient, injects a high-frequency harmonic signal into the input current through the PFC circuit, thereby realizing the function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit, thereby ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standard; and further reducing the heat generation of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0022] In order to achieve the above-mentioned object, a fifth aspect of the present invention provides a household appliance, including the aforementioned PFC controller or the aforementioned appliance electronic control device.

[0023] According to the household appliance of the embodiment of the present invention, through the aforementioned PFC controller or the aforementioned equipment electronic control device, the heat generated by the bus capacitor in the household appliance can be further reduced while ensuring that the household appliance meets the requirements of the product harmonic certification standard, thereby effectively improving the reliability and service life of the capacitor in the household appliance.

[0024] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 is a circuit diagram of an electronic control device for equipment according to an embodiment of the present invention;

[0026] Figure 2 A schematic diagram of current waveform changes in an electric control device of an equipment according to an embodiment of the present invention;

[0027] Figure 3 Schematic diagram of input voltage and current waveforms of an equipment electronic control device according to an embodiment of the present invention;

[0028] Figure 4 is a schematic diagram of input voltage and current waveforms of an equipment electronic control device according to another embodiment of the present invention;

[0029] Figure 5 is a flow chart of a harmonic control method according to an embodiment of the present invention;

[0030] Figure 6a-6b Schematic diagram of input current waveform after high-frequency harmonic injection according to some embodiments of the present invention;

[0031] Figure 7 is a flow chart of a harmonic control method according to another embodiment of the present invention;

[0032] Figure 8 A schematic diagram of the structure of a PFC controller according to an embodiment of the present invention;

[0033] Fig. 9 is a schematic structural diagram of an electronic control device for equipment according to an embodiment of the present invention;

[0034] Figures 10a to 10b FIG. 1 is a schematic structural diagram of a household appliance according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present invention, and should not be construed as limiting the present invention.

[0036] The following describes a harmonic current control method and a computer-readable storage medium, a PFC controller, an equipment electronic control device, and a household appliance proposed in an embodiment of the present invention with reference to the accompanying drawings.

[0037] It should be noted that the harmonic current control method of the embodiment of the present invention can be applied to the electronic control device of the equipment with PFC circuit. Figure 1 Take the electronic control device of the equipment shown in the figure as an example, refer to Figure 1 As shown, the electronic control device 100 of the equipment includes a rectifier circuit 110, a PFC circuit 120, a control unit 130 and a bus capacitor C. The input end of the rectifier circuit 110 is connected to the AC input power source VIN, the output end of the rectifier circuit 110 is connected to the input end of the PFC circuit 120, the output end of the PFC circuit 120 is connected to the load 200, the bus capacitor C is connected in parallel to the output end of the PFC circuit, and the control unit 130 is used to collect the current and voltage on the rectifier circuit 110, the PFC circuit 120 and the bus capacitor C, and to control the on and off of the PFC circuit 120.

[0038] Specifically, refer to Figure 1 As shown, the rectifier circuit 110 may include first to fourth diodes (D1-D4), and these four diodes may realize a full-bridge rectifier function to rectify the input current Iin into a bus capacitor input current Ici with an AC component, such as Figure 2 The PFC circuit 120 may be an active PFC circuit, see Figure 1 As shown, the PFC circuit 120 includes a first switch tube Q1, an inductor L and a fifth diode D5. When the PFC function needs to be turned on, the control unit 130 can realize the power factor correction function of the PFC circuit 120 by controlling the on and off of the first switch tube Q1. The specific process is as follows: When the PFC circuit 120 is not turned on, the input voltage and input current of the PFC circuit 120 can be as follows Figure 3 As shown, the input voltage refers to the voltage input to the rectifier circuit 110 from the AC side, that is, Figure 3 The input current Uin shown in FIG. 1 refers to the current input to the rectifier circuit 110 from the AC side, that is, Figure 3 As shown in Iin. Figure 3 As shown in FIG. 1 , when the PFC circuit 120 is not turned on, the current waveform is greatly distorted, resulting in a low power factor. When the PFC circuit 120 is turned on, the input voltage Uin and the input current Iin of the PFC circuit 120 can be as follows: Figure 4 As shown, at this time, the input voltage is still a sine wave, while the input current becomes a waveform similar to a sine wave and changes with the input voltage. At this time, the input power of the bus capacitor C also fluctuates greatly, and the frequency is twice the input voltage frequency. As a result, the input current Ici of the bus capacitor C also fluctuates greatly. The specific principle is not expanded here. In the equipment electronic control device 100, the bus capacitor C is mainly used to convert the bus capacitor input current Ici with large fluctuations into a relatively stable bus capacitor output current Ico, and provide it to the load 200, such as Figure 2 The greater the fluctuation of the bus capacitor input current Ici, the more intense the bus capacitor C needs to be charged and discharged to maintain the stability of the bus output current Ico. Therefore, the increase in the fluctuation of the bus capacitor input current Ici will lead to an increase in the heat generation of the bus capacitor, thereby reducing the life of the bus capacitor.

[0039] Figure 5 is a flowchart of a harmonic current control method according to an embodiment of the present invention, referring to Figure 5 As shown, the method includes:

[0040] S11, when the PFC circuit is turned on, determining the operating parameters of the PFC circuit.

[0041] Specifically, the operating parameters refer to the various parameters in the PFC circuit that can reflect the magnitude of the high-frequency harmonic current in the input current when the PFC circuit is turned on and the high-frequency harmonic injection method is used to reduce the peak value of the input current waveform of the PFC circuit. The operating parameters may include the power, input current, bus capacitor input current and other parameters of the PFC circuit.

[0042] Among them, the method of using high-frequency harmonic injection to reduce the waveform peak of the PFC circuit is as follows:

[0043] When the PFC circuit is not turned on, the input current Iin can be calculated by the following formula (1):

[0044] Iin=Im×sin(ωt) (1)

[0045] Where Iin is the input current, Im is the amplitude of the input current, and ωt is the fundamental phase of the input current. When the PFC circuit is turned on and a high-frequency harmonic signal is injected, the injected high-frequency harmonic signal can be expressed by the following formula (2):

[0046] Iin1=KP×In×sin(nωt) (2)

[0047] Among them, Iin1 is the current of the high-frequency harmonic signal, n is the harmonic order, In is the amplitude of the nth harmonic current, KP is the compensation coefficient, and nωt represents the phase of the high-frequency harmonic current. According to the above formulas (1) and (2), when the PFC circuit is turned on and the high-frequency harmonic signal is injected, the input current on the AC side is as shown in the following formula (3):

[0048] Iin2=Im×sin(ωt)+KP×In×sin(nωt) (3)

[0049] Among them, Iin2 is the input current after superimposing the high-frequency harmonic current, and the other physical quantities are the same as the above formulas (2) and (3). It can be seen from the above formula (3) that when the high-frequency harmonic current is superimposed, by selecting a suitable n value, such as when the n value is 3 or 5, the high-frequency harmonic signal can achieve the effect of suppressing the waveform peak of the input current. At this time, the intensity of the charging and discharging of the bus capacitor will decrease, so the heat generated by the bus capacitor can be reduced, thereby improving the reliability and service life of the bus capacitor.

[0050] In some embodiments, the operating parameter includes at least one of a power factor, an input current, and load information of the PFC circuit.

[0051] Further, when the operating parameter is the power factor, the power factor is determined according to the maximum power and input power of the PFC circuit.

[0052] Specifically, the power coefficient of the PFC circuit refers to the ratio of the maximum power of the PFC circuit to the input power, that is, the power coefficient can be calculated by the following formula (4):

[0053] KW=Pmax / Pin (4)

[0054] Among them, KW represents the power coefficient of the PFC circuit, PMAX represents the maximum power of the PFC circuit, which is a constant, and PIN represents the input power. It can be seen from the above formula (4) that the power coefficient KW can represent the power size of the current device electronic control device. The larger the power coefficient, the smaller the input power, and the smaller the input power, the smaller the fundamental amplitude of the input current of the bus capacitor. It can be seen from the above formula (2) that the amplitude of the high-frequency harmonic current is determined by the amplitude of the nth harmonic current and the compensation coefficient, and the amplitude of the nth harmonic current is one-nth of the fundamental amplitude of the input current, where n is the high-frequency harmonic order. For example, when the harmonic order is 3, the amplitude of the nth harmonic current is one-third of the fundamental amplitude of the input current. Therefore, the power coefficient of the PFC circuit is inversely correlated with the high-frequency harmonic current in the input current, that is, the larger the power coefficient, the smaller the high-frequency harmonic current in the input current. It can be seen that the power coefficient can reflect the magnitude of the high-frequency harmonic current in the input current.

[0055] The input current refers to the current input to the PFC circuit on the AC side. From the above analysis, it can be seen that the input current is positively correlated with the high-frequency harmonic current in the input current. Therefore, the input current can also reflect the magnitude of the high-frequency harmonic current in the input current.

[0056] Load information refers to information such as the load size of the current equipment electronic control device. Since the load may generate high-frequency harmonics and map them to the input current, the load information is also related to the high-frequency harmonic components of the input current. For example, when the load is large, the high-frequency harmonic components mapped to the input current are large. Therefore, the load information can also reflect the size of the high-frequency harmonic current in the input current.

[0057] As can be seen from the above, the parameters of power factor, input current and load information can all reflect the magnitude of high-frequency harmonic current in the input current, so at least one of these parameters can be selected as the working parameter.

[0058] Further, when the load of the PFC circuit is a compressor, the load information includes the frequency of the compressor.

[0059] Specifically, since the compressor usually works at a variable frequency, when the load of the PFC circuit is the compressor, the compressor frequency will also affect the high-frequency harmonic components mapped into the input current. Therefore, the load information may include the compressor frequency.

[0060] S12, determining a compensation coefficient according to the working parameters, and injecting a high-frequency harmonic signal into the input current through the PFC circuit according to the compensation coefficient, wherein the high-frequency harmonic signal is used to suppress the waveform peak of the input current.

[0061] Specifically, as shown in formula (3), the effect of the high-frequency harmonic signal on suppressing the peak value of the input current waveform is positively correlated with the compensation coefficient KP. For example, when the compensation coefficient is 0.25 and the high-frequency harmonic orders are 3 and 5, the input current after superimposing the high-frequency harmonic signal is as follows: Figure 6a As shown in the synthetic current in; when the compensation coefficient is 0.5, the input current after superimposing the high-frequency harmonic signal is as follows Figure 6b The resultant current is shown in Figure 2. Figure 6a and Figure 6bIt can be seen that, when the number of high-frequency harmonics is determined, the larger the compensation coefficient KP is, the better the effect of suppressing the waveform peak of the input current is, but the high-frequency harmonic component in the input current is also larger. When household appliances such as air conditioners are put on the market, they need to be certified by the electromagnetic compatibility (EMC) standard. The relevant standard GB17625.1 gives the limit values ​​of each high-frequency harmonic. For example, the maximum allowable harmonic current of the third harmonic of Class A equipment is 2.3A. Therefore, in the related technology, a smaller fixed compensation coefficient is usually used to limit the high-frequency harmonics of the input current. For example, the compensation coefficient is uniformly set to 0.25. Although this avoids the problem of excessive high-frequency harmonics, it will also weaken the effect of reducing the heating of the bus capacitor. In the embodiment of the present invention, the harmonic component of the input current in the PFC circuit is determined according to the working parameters at this time, and the corresponding compensation coefficient is determined accordingly, and then a high-frequency harmonic signal is generated according to the determined compensation coefficient, and then the high-frequency harmonic signal is injected into the input current through the PFC circuit to achieve the effect of reducing the heating of the bus capacitor. Among them, since the compensation coefficient is determined based on the harmonic component of the input current, and the compensation coefficient can determine the amplitude of the high-frequency harmonic signal, a suitable compensation coefficient can be selected to make the amplitude of the high-frequency harmonic signal smaller, so as to ensure that the harmonic component of the input current is within the specified range, while maximizing the effect of suppressing the harmonic peak. This can not only ensure that the equipment's electronic control device meets the product harmonic certification standard requirements, but also enhance the effect of reducing the heat generated by the bus capacitor.

[0062] In the above embodiment, when the PFC circuit is turned on, the operating parameters of the PFC circuit are first determined, and then the compensation coefficient is determined based on the operating parameters. According to the compensation coefficient, a high-frequency harmonic signal is injected into the input current through the PFC circuit, thereby realizing the function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit, thereby ensuring that the equipment electronic control device meets the product harmonic certification standard requirements; and further reducing the heat generation of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0063] In some embodiments, the compensation coefficient is determined according to the operating parameters, including: when the power coefficient is greater than a first preset value, determining a first target value as the compensation coefficient; when the power coefficient is less than or equal to a second preset value, determining a second target value as the compensation coefficient, wherein the second preset value is less than the first preset value, and the second target value is less than the first target value; when the power coefficient is less than or equal to the first preset value and greater than the second preset value, determining the compensation coefficient according to the power coefficient and the second target value.

[0064] Specifically, when the operating parameter is the power coefficient, the method for determining the compensation coefficient according to the operating parameter is as follows:

[0065] When the power factor is greater than the first preset value, it means that the power factor is large, the input power of the PFC circuit is small, and correspondingly, the input current of the PFC circuit is also small. At this time, a larger first target value can be selected as the compensation factor. The first target value is selected as follows: when the compensation factor is the first target value and the power factor is the first preset value, the high-frequency harmonic component in the input current does not exceed the product harmonic certification standard requirements, so that the bus capacitor heat can be reduced to the maximum extent within the allowable range of the harmonic current.

[0066] When the power factor is less than or equal to the second preset value, it means that the power factor is small, the input power of the PFC circuit is large, and correspondingly, the input current of the PFC circuit is also large. At this time, a smaller second target value can be selected as the compensation factor. The second target value is selected as follows: when the compensation factor is the second target value and the power factor is the second preset value, the high-frequency harmonic component in the input current does not exceed the product harmonic certification standard requirements, thereby meeting the demand for suppressing the waveform peak of the input current while minimizing the high-frequency harmonics in the input current, ensuring that the PFC circuit can meet the product harmonic certification standards.

[0067] When the power coefficient is less than or equal to the first preset value and greater than the second preset value, the power coefficient and harmonic components of the PFC circuit can be dynamically balanced, and the optimal compensation coefficient can be determined according to the power coefficient and the second target value. For example, the product of the power coefficient and the second target value can be used as the compensation coefficient. The specific principle is as follows:

[0068] As can be seen from the above, the power factor is inversely proportional to the input power, while the input power is proportional to the input current, and the input current is proportional to the amplitude of the high-frequency harmonic current. Therefore, the power factor is inversely proportional to the amplitude of the high-frequency harmonic current. At the same time, it can be seen from the above formula (2) that the amplitude of the high-frequency harmonic current is determined by the amplitude of the high-frequency harmonic current and the compensation coefficient. Therefore, when the product of the power factor and the second target value is selected as the compensation coefficient, if the power factor increases, the input current amplitude increases, and the compensation coefficient decreases, so that the amplitude of the high-frequency harmonic current can be maintained within a fixed range, thereby ensuring that when the power factor is less than or equal to the first preset value and greater than the second preset value, the high-frequency harmonic component in the input current can still meet the product harmonic certification standard requirements.

[0069] Therefore, through the above compensation coefficient determination method, it is possible to ensure that the high-frequency harmonic component of the input current meets the product harmonic certification standard requirements, and to improve the effect of reducing the heat generated by the bus capacitor, thereby further improving the reliability and service life of the bus capacitor.

[0070] As a specific example, see Figure 7 As shown, the harmonic current control method may include:

[0071] S101, Start.

[0072] S102, Determine whether the PFC circuit is turned on. If not, execute S103; if so, execute S104.

[0073] S103, Set the compensation coefficient KP to zero.

[0074] S104, Determine whether the power factor KW is greater than 2. If so, execute S105; if not, execute S106.

[0075] S105, Set the compensation coefficient KP to 0.5.

[0076] S106, Determine whether the power factor kW satisfies 1.2 < kW ≤ 2. If so, execute S107; if not, execute S108.

[0077] S107, Set the compensation coefficient KP to 0.25 times the power factor.

[0078] S108, Set the compensation coefficient KP to 0.25.

[0079] As can be seen from the above, the harmonic current control method of the embodiment of the present invention divides the equipment electronic control device into three parts: low, medium, and high according to the power factor. Among them, the low-power part corresponds to a power factor greater than 2, the medium-power part corresponds to a power factor between 1.2 and 2, and the high-power part corresponds to a power factor less than or equal to 1.2. At the same time, by increasing the compensation coefficient of the low-power part to 0.5, the compensation coefficient of the medium-power part is in the range of 0.5 - 0.3, and the compensation coefficient of the high-power part is maintained at 0.25, which is equivalent to increasing the average compensation coefficient to 0.4. Compared with the method of uniformly maintaining the compensation coefficient at 0.25 in the related art, the harmonic current control method of the embodiment of the present invention can not only meet the requirements of the product harmonic certification standard, but also increase the average compensation coefficient to further reduce the heat generation of the capacitor, thereby effectively improving the reliability and service life of the capacitor.

[0080] In some embodiments, before the PFC circuit is turned on, the method further includes: obtaining the input current of the PFC circuit; and determining that the PFC circuit is turned on when the input current of the PFC circuit is greater than or equal to a preset current threshold.

[0081] Further, when the input current of the PFC circuit is less than the preset current threshold, the method further includes: determining that the compensation coefficient is zero.

[0082] Specifically, the preset current threshold represents the critical threshold at which the input current causes the bus capacitor to charge and discharge strongly. When the input current is greater than or equal to the preset current threshold, it means that the input current is large, and the waveform peak of the input current needs to be limited to reduce the heat generated by the bus capacitor. At this time, it can be determined that the PFC circuit is turned on. When the input current is less than the preset current threshold, it means that the input current is small at this time, and the heat generated by the bus capacitor is low. There is no need to suppress the waveform peak of the input current. At this time, the PFC circuit can be turned off to save the power consumption of the PFC circuit; at the same time, the compensation coefficient can be set to zero to facilitate subsequent adjustment of the compensation coefficient.

[0083] In summary, according to the harmonic current control method of the embodiment of the present invention, when the PFC circuit is turned on, the operating parameters of the PFC circuit are first determined, and then the compensation coefficient is determined based on the operating parameters. According to the compensation coefficient, a high-frequency harmonic signal is injected into the input current through the PFC circuit, thereby realizing the function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit, thereby ensuring that the equipment electronic control device meets the product harmonic certification standard requirements; and further reducing the heat generation of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0084] Corresponding to the above embodiment, an embodiment of the present invention further provides a computer-readable storage medium, on which a harmonic current control program is stored. When the harmonic current control program is executed by a processor, the above-mentioned harmonic current control method is implemented.

[0085] According to the computer-readable storage medium of an embodiment of the present invention, through the aforementioned harmonic current control method, the heat generated by the bus capacitor in the equipment electronic control device can be further reduced while ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standards, thereby effectively improving the reliability and service life of the capacitor.

[0086] Corresponding to the above embodiment, the embodiment of the present invention further provides a PFC controller, referring to Figure 8 As shown, the PFC controller 200 includes: a memory 210, a processor 220, and a harmonic current control program stored in the memory 210 and executable on the processor 220. When the processor 220 executes the program, the aforementioned harmonic current control method is implemented.

[0087] According to the PFC controller of the embodiment of the present invention, through the aforementioned harmonic current control method, it is possible to further reduce the heat generated by the bus capacitor in the device electronic control device while ensuring that the device electronic control device meets the product harmonic certification standard requirements, thereby effectively improving the reliability and service life of the capacitor, and at the same time improving

[0088] Corresponding to the above embodiment, the embodiment of the present invention further provides an electric control device for equipment, referring to Fig. 9 As shown, the electronic control device 1000 of the equipment includes: a PFC circuit 1100 and a controller 1200. The controller 1200 is configured to determine the working parameters of the PFC circuit 1100 when the PFC circuit 1100 is turned on, and determine the compensation coefficient according to the working parameters. According to the compensation coefficient, a high-frequency harmonic signal is injected into the input current through the PFC circuit, wherein the high-frequency harmonic signal is used to suppress the waveform peak of the input current.

[0089] According to an embodiment of the present invention, the operating parameter includes at least one of a power factor, an input current and load information of the PFC circuit.

[0090] According to an embodiment of the present invention, when the load of the PFC circuit 1100 is a compressor, the load information includes the compressor frequency.

[0091] According to an embodiment of the present invention, when the operating parameter is the power factor, the power factor is determined according to the maximum power and input power of the PFC circuit 1100 .

[0092] According to one embodiment of the present invention, the controller 1200 is also used to: when the power coefficient is greater than a first preset value, determine a first target value as a compensation coefficient; when the power coefficient is less than or equal to a second preset value, determine a second target value as a compensation coefficient, wherein the second preset value is less than the first preset value, and the second target value is less than the first target value; when the power coefficient is less than or equal to the first preset value and greater than the second preset value, determine the compensation coefficient based on the power coefficient and the second target value.

[0093] According to an embodiment of the present invention, before the PFC circuit is turned on, the controller 1200 is further used to: obtain the input current of the PFC circuit; and determine that the PFC circuit is turned on when the input current of the PFC circuit is greater than or equal to a preset current threshold.

[0094] According to an embodiment of the present invention, when the input current of the PFC circuit is less than a preset current threshold, the controller 1200 is further configured to determine that the compensation coefficient is zero.

[0095] It should be noted that, for the description of the electronic control device of the equipment in this application, please refer to the description of the harmonic current control method in this application, and the details will not be repeated here.

[0096] According to the equipment electronic control device of the embodiment of the present invention, when the PFC circuit is turned on, the controller determines the operating parameters of the PFC circuit, then determines the compensation coefficient based on the operating parameters, and according to the compensation coefficient, injects a high-frequency harmonic signal into the input current through the PFC circuit, thereby realizing the function of determining the high-frequency harmonic signal injected into the input current according to the working condition of the PFC circuit, thereby ensuring that the equipment electronic control device meets the requirements of the product harmonic certification standard; and further reducing the heat generation of the bus capacitor in the equipment electronic control device, effectively improving the reliability and service life of the capacitor.

[0097] Corresponding to the above embodiment, the embodiment of the present invention further provides a household appliance, referring to Fig.10a As shown in FIG. 10 b , the household appliance 10000 includes the aforementioned PFC controller 200 or the aforementioned appliance electronic control device 1000 .

[0098] According to the household appliance of the embodiment of the present invention, through the aforementioned controller or the aforementioned equipment electronic control device, the heat generated by the bus capacitor in the household appliance can be further reduced while ensuring that the household appliance meets the requirements of the product harmonic certification standards, thereby effectively improving the reliability and service life of the capacitor.

[0099] It should be noted that the logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purposes of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection portion with one or more wirings (electronic device), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically, for example, by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways if necessary, and then stored in a computer memory.

[0100] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware or a combination thereof. In the above-mentioned embodiments, a plurality of steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0101] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner.

[0102] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "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.

[0103] In the present invention, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it 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.

[0104] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A harmonic current control method, characterized in that: Applied to an electronic control device of an equipment, the electronic control device of the equipment includes a PFC circuit, and the method includes: When the PFC circuit is turned on, determining operating parameters of the PFC circuit; A compensation coefficient is determined according to the working parameter, and a high-frequency harmonic signal is injected into the input current through the PFC circuit according to the compensation coefficient, wherein the high-frequency harmonic signal is used to suppress the waveform peak of the input current.

2. The method according to claim 1, characterized in that The operating parameter includes at least one of a power factor, an input current and load information of the PFC circuit.

3. The method according to claim 2, characterized in that In the case that the load of the PFC circuit is a compressor, the load information includes a compressor frequency.

4. The method according to claim 2, characterized in that: When the operating parameter is the power factor, the power factor is determined according to the maximum power and input power of the PFC circuit.

5. The method according to claim 4, characterized in that Determining a compensation coefficient according to the working parameters includes: When the power coefficient is greater than a first preset value, determining a first target value as the compensation coefficient; In the case where the power coefficient is less than or equal to a second preset value, determining a second target value as the compensation coefficient, wherein the second preset value is less than the first preset value, and the second target value is less than the first target value; When the power coefficient is less than or equal to a first preset value and greater than a second preset value, the compensation coefficient is determined according to the power coefficient and the second target value.

6. The method according to any one of claims 1 to 5, characterized in that Before the PFC circuit is turned on, the method further includes: Obtaining an input current of the PFC circuit; When the input current of the PFC circuit is greater than or equal to a preset current threshold, it is determined that the PFC circuit is turned on.

7. The method according to claim 6, characterized in that When the input current of the PFC circuit is less than a preset current threshold, the method further includes: The compensation coefficient is determined to be zero.

8. A computer-readable storage medium, characterized in that: A harmonic current control program is stored thereon, and when the harmonic current control program is executed by a processor, the harmonic current control method according to any one of claims 1-7 is implemented.

9. A PFC controller, characterized in that: include: A memory, a processor, and a harmonic current control program stored in the memory and executable on the processor, wherein when the processor executes the program, the harmonic current control method according to any one of claims 1 to 7 is implemented.

10. An electronic control device for equipment, characterized in that: include: PFC circuit; The controller is configured to determine operating parameters of the PFC circuit when the PFC circuit is turned on, and determine a compensation coefficient according to the operating parameters, and inject a high-frequency harmonic signal into an input current through the PFC circuit according to the compensation coefficient, wherein the high-frequency harmonic signal is used to suppress a waveform peak of the input current.

11. A household appliance, characterized in that: It comprises the PFC controller according to claim 9 or the equipment electronic control device according to claim 10.

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