PFC current feedback control method and device based on average current detection

Abstract

The present invention discloses a PFC current feedback control method and device based on average current detection, which obtains the first inductor current ADC sampling value at the carrier zero point and the second inductor current ADC sampling value at the carrier vertex, calculates the current current difference between the two and determines the corresponding target current value interval; obtains the current target current control strategy corresponding to the target current value interval, and determines the current average current in combination with the first inductor current ADC sampling value and the second inductor current ADC sampling value, and uses it as the feedback amount of the target control loop. The embodiment of the present invention determines the target current value interval and the corresponding current target current control strategy by calculating the difference between the first inductor current ADC sampling value at the carrier zero point and the second inductor current ADC sampling value at the carrier vertex, and determines a more accurate current average current based on the current target current control strategy to avoid the increase of input current harmonics.

Description

Technical Field

[0001] The present invention relates to the field of PFC control technology, and in particular to a PFC current feedback control method and device based on average current detection. Background Art

[0002] The average current control scheme is often used in the digital control of the current loop of high-power PFC (Power Factor Correction) such as charging modules. Due to the wide load and input voltage range, the PFC current may operate in discontinuous conduction mode (DCM). At this time, the average current deviation obtained by the conventional carrier zero-crossing sampling scheme is large, resulting in an increase in input current harmonics, which may seriously affect the stable operation of the system. Summary of the invention

[0003] The embodiments of the present invention provide a PFC current feedback control method and device based on average current detection, aiming to solve the problem that in the prior art, high-power PFC current loop digital control often adopts average current control. If the average current deviation obtained by the conventional carrier zero-crossing sampling scheme in the discontinuous mode is large, the input current harmonics will increase, which may seriously affect the stable operation of the system.

[0004] In a first aspect, an embodiment of the present invention provides a PFC current feedback control method based on average current detection, which includes:

[0005] Acquire a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak point;

[0006] Acquire a current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference in a plurality of preset current value intervals;

[0007] A current target current control strategy corresponding to the target current value interval is obtained, a current average current is determined according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value, and the current average current is used as a feedback amount of a target control loop.

[0008] In a second aspect, an embodiment of the present invention further provides a PFC current feedback control device based on average current detection, which includes:

[0009] A current ADC sampling unit, used to obtain a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak;

[0010] a target current value interval acquisition unit, configured to acquire a current current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference in a plurality of preset current value intervals;

[0011] a current average current acquisition unit, used for acquiring a current target current control strategy corresponding to the target current value interval, determining a current average current according to the current target current control strategy, the first inductor current ADC sampling value and the second inductor current ADC sampling value, and using the current average current as a feedback amount of a target control loop.

[0012] In a third aspect, an embodiment of the present invention further provides a computer device, which includes a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the method described in the first aspect is implemented.

[0013] In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, wherein the computer storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the method described in the first aspect above can be implemented.

[0014] The embodiment of the present invention provides a PFC current feedback control method and device based on average current detection, the method comprising: obtaining a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier vertex; obtaining a current current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determining a target current value interval of the current current difference in a plurality of preset current value intervals; obtaining a current target current control strategy corresponding to the target current value interval, determining a current average current according to the current target current control strategy, the first inductor current ADC sampling value and the second inductor current ADC sampling value, and using the current average current as the feedback amount of the target control loop. The embodiment of the present invention determines the target current value interval and the corresponding current target current control strategy by calculating the difference between the first inductor current ADC sampling value at a carrier zero point and the second inductor current ADC sampling value at a carrier vertex, and determines a more accurate current average current based on the current target current control strategy to avoid the increase of input current harmonics. BRIEF DESCRIPTION OF THE DRAWINGS

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

[0016] Figure 1 A schematic flow chart of a PFC current feedback control method based on average current detection provided by an embodiment of the present invention;

[0017] Figure 2 A circuit diagram of a PFC control circuit applied to a PFC current feedback control method based on average current detection provided by an embodiment of the present invention;

[0018] Figure 3 A waveform diagram of a carrier signal, a comparison signal, a sampling signal and an inductor current ADC sampling value used in a PFC current feedback control method based on average current detection provided in an embodiment of the present invention;

[0019] Figure 4 A schematic diagram of a sub-process of a PFC current feedback control method based on average current detection provided by an embodiment of the present invention;

[0020] Figure 5 A schematic diagram of a sub-process of a PFC current feedback control method based on average current detection provided by an embodiment of the present invention;

[0021] Figure 6 A schematic block diagram of a PFC current feedback control device based on average current detection provided by an embodiment of the present invention;

[0022] Figure 7 A schematic block diagram of a computer device provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0023] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] It should be understood that when used in this specification and the appended claims, the terms "include" and "comprises" indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0025] It should also be understood that the terms used in this specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the specification of the present invention and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0026] It should be further understood that the term "and / or" used in the present description and the appended claims refers to and includes any and all possible combinations of one or more of the associated listed items.

[0027] See also Figure 1 , which is a flow chart of a PFC current feedback control method based on average current detection provided by an embodiment of the present invention. Figure 1 As shown, the PFC current feedback control method based on average current detection includes steps S110 to S130.

[0028] S110 , obtaining a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak point.

[0029] In this embodiment, the PFC current feedback control method based on average current detection described in this application is applied to a PFC control circuit (which can also be understood as a target control loop). In order to accurately obtain the current feedback amount of the PFC control circuit, reference can be made to the following. Figure 3 The waveform diagram of the carrier signal, comparison signal, sampling signal and inductor current ADC sampling value in FIG. 1 can obtain the first inductor current ADC sampling value i at the carrier zero point. L_up , and obtain the second inductor current ADC sampling value i at the carrier vertex L_dn . It should be noted that the present application uses a carrier cycle time interval as an example to illustrate the process of obtaining the current average current, that is, if it is determined that the starting time point of the current carrier cycle, the steps in step S110 are executed, and the current average current is determined by the same process in other carrier cycles. Moreover, the first inductor current ADC sampling value and the second inductor current ADC sampling value obtained cannot be directly used to determine the current average current, and subsequent processing is required.

[0030] The PFC current feedback control method based on average current detection described in this application is applied to a PFC control circuit, and the specific circuit of the PFC control circuit is as follows: Figure 2As shown. The PFC control circuit specifically includes an inductor L1, a switch tube Q1, a diode (specifically including 5 diodes, and respectively recorded as a first diode D1, a second diode D2, a third diode D3, a fourth diode D4 and a fifth diode D5) arranged in a preset connection mode, a capacitor C1 and a load resistor RL. More specifically, the cathode of the second diode D2 is connected to the anode of the first diode D1, and is also connected to a power source (for example, the power source is a power grid, and its input voltage is u g ) is connected to the positive electrode of the first diode D1; the negative electrode of the first diode D1 is connected to the first end of the inductor L1; the negative electrode of the fourth diode D4 is connected to the positive electrode of the third diode D3, and is also connected to the negative electrode of the power supply; the negative electrode of the third diode D3 is connected to the first end of the inductor L1; the second end of the inductor L1 is connected to the drain of the switch tube Q1 (specifically a metal-oxide-semiconductor field effect transistor or an insulated gate bipolar transistor), and is also connected to the positive electrode of the fifth diode D5; the source of the switch tube Q1 is connected to the positive electrode of the second diode D2 and the positive electrode of the fourth diode D4; the negative electrode of the fifth diode D5 is connected to the first end of the capacitor C1, and is also connected to the first end of the load resistor RL; the second end of the capacitor C1 is connected to the source of the switch tube Q1; the second end of the load resistor RL is connected to the source of the switch tube Q1.

[0031] Moreover, for Figure 2 When the current passing through the inductor L1 in the PFC control circuit shown in FIG. 1 is sampled by ADC at the carrier zero point, the first inductor current ADC sampling value i is obtained. L_up , and the current passing through the inductor L1 is sampled by ADC at the carrier vertex to obtain the second inductor current ADC sampling value i L_dn . Refer again Figure 3 , in one carrier cycle T of the sampling signal s s The open time T of a carrier cycle is included on and the off time T of one carrier cycle off , and satisfies T on +T off =T s ,and Figure 3 Carry corresponds to the waveform of the carrier signal, and CMP corresponds to the waveform of the carrier signal. The on-time T of a carrier cycle on In the corresponding time interval, the current passing through the inductor L1 is sampled by ADC at the carrier zero point to obtain the first inductor current ADC sampling value i L_up , and in the off time T of a carrier cycle off In the corresponding time interval, the current passing through the inductor L1 is sampled by ADC at the carrier vertex to obtain the second inductor current ADC sampling value i L_dn .

[0032] S120: Obtain a current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference among a plurality of preset current value intervals.

[0033] In this embodiment, when obtaining the first inductor current ADC sampling value i at the carrier zero point L_up , and obtain the second inductor current ADC sampling value i at the carrier vertex L_dn Afterwards, the current current difference between the two can be calculated and determined first. Afterwards, in order to more accurately determine the interval to which the current current difference belongs in multiple preset current value intervals, the current current difference can be matched with multiple preset current value intervals respectively, so as to quickly determine the target current value interval to which the current current difference belongs.

[0034] In one embodiment, if Figure 4 As shown, step S120 includes:

[0035] S121, obtaining an absolute value of a first current sampling value corresponding to the first inductor current ADC sampling value, and obtaining an absolute value of a second current sampling value corresponding to the second inductor current ADC sampling value;

[0036] S122. Determine the current difference based on the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value.

[0037] In this embodiment, specifically, the absolute value of the first current sampling value corresponding to the first inductor current ADC sampling value is first obtained. L_up |, and obtain the absolute value of the second current sampling value corresponding to the second inductor current ADC sampling value |i L_dn |, then calculate the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value |i L_up |-|i L_dn |, and end with |i L_up |-|i L_dn | as the current current difference. It can be seen that the current current difference can be quickly determined through the above method.

[0038] In one embodiment, as a first embodiment of determining a target current value interval of the current current difference value in a plurality of preset current value intervals after step S122, the method includes:

[0039] If it is determined that the current current difference belongs to the first preset current value interval among the multiple preset current value intervals, the first preset current value interval is used as the target current value interval; wherein the first preset current value interval is (-∞, Δi1), and Δi1 is a first preset current threshold.

[0040] In this embodiment, as a first embodiment for further determining the target current value interval to which the current current difference belongs after step S122, when determining the current current difference |i L_up |-|i L_dn |<Δi1 (where Δi1 is the first preset current threshold), it means that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a smaller difference, and it can be determined that it belongs to the first preset current value interval among the multiple preset current value intervals, and the first preset current value interval is used as the target current value interval. It can be seen that through this comparison method, the target current value interval to which the current current difference belongs can be quickly determined.

[0041] In one embodiment, as a second embodiment of determining a target current value interval of the current current difference value in a plurality of preset current value intervals after step S122, the method includes:

[0042] If it is determined that the current current difference belongs to the second preset current value interval among the multiple preset current value intervals, the second preset current value interval is used as the target current value interval; wherein the second preset current value interval is (Δi2, +∞), and Δi2 is a second preset current threshold.

[0043] In this embodiment, as a second embodiment for further determining the target current value interval to which the current current difference belongs after step S122, when determining the current current difference |i L_up |-|i L_dn | is greater than Δi2 (where Δi2 is the second preset current threshold), it means that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a larger difference, and it can be determined that it belongs to the second preset current value interval among the multiple preset current value intervals, and the second preset current value interval is used as the target current value interval. It can be seen that through this comparison method, the target current value interval to which the current difference belongs can be quickly determined.

[0044] S130, obtaining a current target current control strategy corresponding to the target current value interval, determining a current average current according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value, and using the current average current as a feedback amount of a target control loop.

[0045] In this embodiment, since a current control strategy is set for each preset current value interval in advance, after determining the target current value interval to which the current current difference belongs, the current target current control strategy corresponding to the target current value interval can be obtained, and the first inductor current ADC sampling value and the second inductor current ADC sampling value are processed accordingly according to the current target current control strategy, so as to determine the current average current. The obtained current average current can be used as the feedback amount of the target control loop in this carrier cycle, so that the target control loop can perform timely feedback control on the current according to the feedback amount, thereby avoiding the increase of input current harmonics.

[0046] In one embodiment, as an embodiment corresponding to the first embodiment of determining the target current value interval of the current current difference value in a plurality of preset current value intervals after step S122, step S130 includes:

[0047] The first inductor current ADC sampling value is selected from the first inductor current ADC sampling value and the second inductor current ADC sampling value based on the current target current control strategy and is used as the current average current.

[0048] In this embodiment, when it is determined that the target current value interval to which the current current difference belongs is the first preset current value interval, the first inductor current ADC sampling value is selected from the first inductor current ADC sampling value and the second inductor current ADC sampling value according to the current target current control strategy corresponding to the first preset current value interval, and the first inductor current ADC sampling value is directly used as the current average current. It can be seen that when it is determined that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a smaller difference, the first inductor current ADC sampling value can be directly used as the current average current to avoid the increase of input current harmonics.

[0049] In one embodiment, as an embodiment corresponding to the second embodiment of determining the target current value interval of the current current difference value in a plurality of preset current value intervals after step S122, as shown in FIG. Figure 5 As shown, step S130 includes:

[0050] S131, obtaining a carrier cycle, an on-time of a carrier cycle, and an off-time of a carrier cycle corresponding to the first inductor current ADC sampling value and the second inductor current ADC sampling value; wherein the on-time of a carrier cycle+the off-time of a carrier cycle=the carrier cycle;

[0051] S132, determining an inductor current duration time corresponding to the carrier cycle, the on time of one carrier cycle, the off time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value based on an inductor current duration time determination sub-strategy preset in the current target current control strategy;

[0052] S133. Determine the current average current corresponding to the first inductor current ADC sampling value, the inductor current duration, and the carrier period based on the average current determination sub-strategy in the current target current control strategy.

[0053] Among them, the formula corresponding to the inductor current duration determination sub-strategy is: , where T len represents the duration of the inductor current in one carrier cycle, T on Indicates the opening time of a carrier cycle, i L_up represents the first inductor current ADC sampling value and i L_dn represents the second inductor current ADC sampling value;

[0054] The formula corresponding to the average current determination sub-strategy is: , where i L_avg Indicates the current average current.

[0055] In this embodiment, when it is determined that the target current value interval to which the current current difference belongs is the second preset current value interval, the current target current control strategy corresponding to the second preset current value interval is used. When determining the current average current based on the current target current control strategy, first, based on the inductor current duration determination sub-strategy preset in the current target current control strategy, the inductor current duration corresponding to the carrier cycle, the on-time of one carrier cycle, the off-time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value is determined, that is, the carrier cycle, the on-time of one carrier cycle, the off-time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value are substituted into the formula corresponding to the inductor current duration determination sub-strategy. Thus, the inductor current duration T is determined len After that, the inductor current duration T len , the first inductor current ADC sampling value and the carrier period are substituted into the formula corresponding to the average current determination sub-strategy to determine the current average current i L_avgIt can be seen that when it is determined that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a large difference, it is necessary to combine the inductor current duration determination sub-strategy and the average current determination sub-strategy in the previous target current control strategy, that is, related parameters to determine the current average current, and the obtained current average current can also avoid the increase of input current harmonics.

[0056] It can be seen that the embodiment of the method determines the target current value range and the corresponding current target current control strategy by calculating the difference between the first inductor current ADC sampling value at the carrier zero point and the second inductor current ADC sampling value at the carrier vertex, and determines a more accurate current average current based on the current target current control strategy to avoid the increase of input current harmonics.

[0057] Figure 6 is a schematic block diagram of a PFC current feedback control device based on average current detection provided by an embodiment of the present invention. Figure 6 As shown, corresponding to the above PFC current feedback control method based on average current detection, the present invention also provides a PFC current feedback control device 100 based on average current detection. The PFC current feedback control device 100 based on average current detection includes: a current ADC sampling unit 110, a target current value interval acquisition unit 120 and a current average current acquisition unit 130.

[0058] The current ADC sampling unit 110 is used to obtain a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak point.

[0059] In this embodiment, the PFC current feedback control method based on average current detection described in this application is applied to a PFC control circuit (which can also be understood as a target control loop). In order to accurately obtain the current feedback amount of the PFC control circuit, reference can be made to the following. Figure 3 The waveform diagram of the carrier signal, comparison signal, sampling signal and inductor current ADC sampling value in FIG. 1 can obtain the first inductor current ADC sampling value i at the carrier zero point. L_up , and obtain the second inductor current ADC sampling value i at the carrier vertex L_dn . It should be noted that the present application uses a carrier cycle time interval as an example to illustrate the process of obtaining the current average current, that is, if it is determined that the starting time point of the current carrier cycle, the steps in step S110 are executed, and the current average current is determined by the same process in other carrier cycles. Moreover, the first inductor current ADC sampling value and the second inductor current ADC sampling value obtained cannot be directly used to determine the current average current, and subsequent processing is required.

[0060] The PFC current feedback control method based on average current detection described in this application is applied to a PFC control circuit, and the specific circuit of the PFC control circuit is as follows: Figure 2 Moreover, Figure 2 When the current passing through the inductor L1 in the PFC control circuit shown in FIG. 1 is sampled by ADC at the carrier zero point, the first inductor current ADC sampling value i is obtained. L_up , and the current passing through the inductor L1 is sampled by ADC at the carrier vertex to obtain the second inductor current ADC sampling value i L_dn . Refer again Figure 3 , in one carrier cycle T of the sampling signal s s The open time T of a carrier cycle is included on and the off time T of one carrier cycle off , and satisfies T on +T off =T s ,and Figure 3 Carry corresponds to the waveform of the carrier signal, and CMP corresponds to the waveform of the carrier signal. The on-time T of a carrier cycle on In the corresponding time interval, the current passing through the inductor L1 is sampled by ADC at the carrier zero point to obtain the first inductor current ADC sampling value i L_up , and in the off time T of a carrier cycle off In the corresponding time interval, the current passing through the inductor L1 is sampled by ADC at the carrier vertex to obtain the second inductor current ADC sampling value i L_dn .

[0061] The target current value interval acquisition unit 120 is used to acquire a current current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference in a plurality of preset current value intervals.

[0062] In this embodiment, when obtaining the first inductor current ADC sampling value i at the carrier zero point L_up , and obtain the second inductor current ADC sampling value i at the carrier vertex L_dn Afterwards, the current current difference between the two can be calculated and determined first. Afterwards, in order to more accurately determine the interval to which the current current difference belongs in multiple preset current value intervals, the current current difference can be matched with multiple preset current value intervals respectively, so as to quickly determine the target current value interval to which the current current difference belongs.

[0063] In one embodiment, the target current value interval acquisition unit 120 is specifically used for:

[0064] Obtaining an absolute value of a first current sampling value corresponding to the first inductor current ADC sampling value, and obtaining an absolute value of a second current sampling value corresponding to the second inductor current ADC sampling value;

[0065] The current difference is determined based on a difference between an absolute value of the first current sampling value and an absolute value of the second current sampling value.

[0066] In this embodiment, specifically, the absolute value of the first current sampling value corresponding to the first inductor current ADC sampling value is first obtained. L_up |, and obtain the absolute value of the second current sampling value corresponding to the second inductor current ADC sampling value |i L_dn |, then calculate the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value |i L_up |-|i L_dn |, and end with |i L_up |-|i L_dn | as the current current difference. It can be seen that the current current difference can be quickly determined through the above method.

[0067] In one embodiment, the target current value interval acquisition unit 120 is further used for:

[0068] If it is determined that the current current difference belongs to the first preset current value interval among the multiple preset current value intervals, the first preset current value interval is used as the target current value interval; wherein the first preset current value interval is (-∞, Δi1), and Δi1 is a first preset current threshold.

[0069] In this embodiment, as a first embodiment for further determining the target current value interval to which the current current difference belongs, when determining the current current difference |i L_up |-|i L_dn |<Δi1 (where Δi1 is the first preset current threshold), it means that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a smaller difference, and it can be determined that it belongs to the first preset current value interval among the multiple preset current value intervals, and the first preset current value interval is used as the target current value interval. It can be seen that through this comparison method, the target current value interval to which the current current difference belongs can be quickly determined.

[0070] In one embodiment, the target current value interval acquisition unit 120 is further used for:

[0071] If it is determined that the current current difference belongs to the second preset current value interval among the multiple preset current value intervals, the second preset current value interval is used as the target current value interval; wherein the second preset current value interval is (Δi2, +∞), and Δi2 is a second preset current threshold.

[0072] In this embodiment, as a second embodiment for further determining the target current value interval to which the current current difference belongs, when determining the current current difference |i L_up |-|i L_dn | is greater than Δi2 (where Δi2 is the second preset current threshold), it means that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a larger difference, and it can be determined that it belongs to the second preset current value interval among the multiple preset current value intervals, and the second preset current value interval is used as the target current value interval. It can be seen that through this comparison method, the target current value interval to which the current difference belongs can be quickly determined.

[0073] The current average current acquisition unit 130 is used to obtain the current target current control strategy corresponding to the target current value interval, determine the current average current according to the current target current control strategy, the first inductor current ADC sampling value and the second inductor current ADC sampling value, and use the current average current as the feedback amount of the target control loop.

[0074] In this embodiment, since a current control strategy is set for each preset current value interval in advance, after determining the target current value interval to which the current current difference belongs, the current target current control strategy corresponding to the target current value interval can be obtained, and the first inductor current ADC sampling value and the second inductor current ADC sampling value are processed accordingly according to the current target current control strategy, so as to determine the current average current. The obtained current average current can be used as the feedback amount of the target control loop in this carrier cycle, so that the target control loop can perform timely feedback control on the current according to the feedback amount, thereby avoiding the increase of input current harmonics.

[0075] In one embodiment, as an embodiment corresponding to the first embodiment of determining a target current value interval of the current current difference in a plurality of preset current value intervals, the current average current acquisition unit 130 is specifically used to:

[0076] The first inductor current ADC sampling value is selected from the first inductor current ADC sampling value and the second inductor current ADC sampling value based on the current target current control strategy and is used as the current average current.

[0077] In this embodiment, when it is determined that the target current value interval to which the current current difference belongs is the first preset current value interval, the first inductor current ADC sampling value is selected from the first inductor current ADC sampling value and the second inductor current ADC sampling value according to the current target current control strategy corresponding to the first preset current value interval, and the first inductor current ADC sampling value is directly used as the current average current. It can be seen that when it is determined that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a smaller difference, the first inductor current ADC sampling value can be directly used as the current average current to avoid the increase of input current harmonics.

[0078] In one embodiment, as an embodiment corresponding to the second embodiment of determining a target current value interval of the current current difference in a plurality of preset current value intervals, the current average current acquisition unit 130 is specifically configured to:

[0079] Obtaining a carrier cycle, an on-time of a carrier cycle, and an off-time of a carrier cycle corresponding to the first inductor current ADC sampling value and the second inductor current ADC sampling value; wherein the on-time of a carrier cycle+the off-time of a carrier cycle=the carrier cycle;

[0080] Based on the inductor current duration determination sub-strategy preset in the current target current control strategy, determine the inductor current duration corresponding to the carrier cycle, the on time of one carrier cycle, the off time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value;

[0081] Based on the average current determination sub-strategy in the current target current control strategy, the current average current corresponding to the first inductor current ADC sampling value, the inductor current duration and the carrier period is determined.

[0082] Among them, the formula corresponding to the inductor current duration determination sub-strategy is: , where T len represents the duration of the inductor current in one carrier cycle, T on Indicates the opening time of a carrier cycle, i L_up represents the first inductor current ADC sampling value and i L_dn represents the second inductor current ADC sampling value;

[0083] The formula corresponding to the average current determination sub-strategy is: , where i L_avg Indicates the current average current.

[0084] In this embodiment, when it is determined that the target current value interval to which the current current difference belongs is the second preset current value interval, the current target current control strategy corresponding to the second preset current value interval is used. When determining the current average current based on the current target current control strategy, first, based on the inductor current duration determination sub-strategy preset in the current target current control strategy, the inductor current duration corresponding to the carrier cycle, the on-time of one carrier cycle, the off-time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value is determined, that is, the carrier cycle, the on-time of one carrier cycle, the off-time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value are substituted into the formula corresponding to the inductor current duration determination sub-strategy. Thus, the inductor current duration T is determined len After that, the inductor current duration T len , the first inductor current ADC sampling value and the carrier period are substituted into the formula corresponding to the average current determination sub-strategy to determine the current average current i L_avg It can be seen that when it is determined that the difference between the absolute value of the first current sampling value and the absolute value of the second current sampling value is a large difference, it is necessary to combine the inductor current duration determination sub-strategy and the average current determination sub-strategy in the previous target current control strategy, that is, related parameters to determine the current average current, and the obtained current average current can also avoid the increase of input current harmonics.

[0085] It can be seen that the embodiment of the device determines the target current value range and the corresponding current target current control strategy by calculating the difference between the first inductor current ADC sampling value at the carrier zero point and the second inductor current ADC sampling value at the carrier vertex, and determines a more accurate current average current based on the current target current control strategy to avoid the increase of input current harmonics.

[0086] An embodiment of the present invention further provides a control circuit, which includes an inductor, a switch tube, a diode, a capacitor and a load resistor arranged in a preset connection manner; the control circuit is used to execute the aforementioned PFC current feedback control method based on average current detection.

[0087] Among them, the control circuit can be specifically applied to control systems such as inverters and DC-DC that require sampling of inductor current, and the control circuit can be specifically applied to devices such as charging pile modules and on-board chargers.

[0088] The above-mentioned PFC current feedback control device based on average current detection can be implemented in the form of a computer program. The computer program can be implemented in the form of a computer program such as Figure 7 Runs on the computer device shown.

[0089] See also Figure 7 , Figure 7 The schematic block diagram of a computer device provided by an embodiment of the present invention is shown in FIG. The computer device integrates any PFC current feedback control device based on average current detection provided by an embodiment of the present invention.

[0090] See also Figure 7 The computer device 400 includes a processor 402 , a memory and a network interface 405 connected via a system bus 401 , wherein the memory may include a storage medium 403 and an internal memory 404 .

[0091] The storage medium 403 may store an operating system 4031 and a computer program 4032. The computer program 4032 includes program instructions, and when the program instructions are executed, the processor 402 may execute the above-mentioned PFC current feedback control method based on average current detection.

[0092] The processor 402 is used to provide computing and control capabilities to support the operation of the entire computer device.

[0093] The internal memory 404 provides an environment for the operation of the computer program 4032 in the storage medium 403 . When the computer program 4032 is executed by the processor 402 , the processor 402 can execute the above-mentioned PFC current feedback control method based on average current detection.

[0094] The network interface 405 is used to communicate with other devices over the network. Figure 7 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present invention, and does not constitute a limitation on the computer device to which the solution of the present invention is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0095] The processor 402 is used to run a computer program 4032 stored in the memory to implement the PFC current feedback control method based on average current detection as described above.

[0096] It should be understood that in the embodiment of the present invention, the processor 402 may be a central processing unit (CPU), and the processor 402 may also be other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), field-programmable gate arrays (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. Among them, the general-purpose processor may be a microprocessor or the processor may also be any conventional processor, etc.

[0097] It can be understood by those skilled in the art that all or part of the processes in the method for implementing the above embodiment can be completed by instructing the relevant hardware through a computer program. The computer program includes program instructions, and the computer program can be stored in a storage medium, which is a computer-readable storage medium. The program instructions are executed by at least one processor in the computer system to implement the process steps of the embodiment of the above method.

[0098] Therefore, the present invention also provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions. When the program instructions are executed by a processor, the processor executes the PFC current feedback control method based on average current detection as described above.

[0099] The computer-readable storage medium may be a USB flash drive, a mobile hard disk, a read-only memory (ROM), a magnetic disk, or an optical disk, etc., which are computer-readable storage media that can store program codes.

[0100] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present invention.

[0101] In the several embodiments provided by the present invention, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic. For example, the division of each unit is only a logical function division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0102] The steps in the method of the embodiment of the present invention can be adjusted in order, combined and deleted according to actual needs. The units in the device of the embodiment of the present invention can be combined, divided and deleted according to actual needs. In addition, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0103] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, terminal, or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention.

[0104] The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of various equivalent modifications or replacements within the technical scope disclosed by the present invention, and these modifications or replacements should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A PFC current feedback control method based on average current detection, characterized in that: include: Acquire a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak point; Acquire a current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference in a plurality of preset current value intervals; Obtaining a current target current control strategy corresponding to the target current value interval, determining a current average current according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value, and using the current average current as a feedback amount of a target control loop; The determining the current average current according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value includes: Obtaining a carrier cycle, an on-time of a carrier cycle, and an off-time of a carrier cycle corresponding to the first inductor current ADC sampling value and the second inductor current ADC sampling value; wherein the on-time of a carrier cycle+the off-time of a carrier cycle=the carrier cycle; Based on the inductor current duration determination sub-strategy preset in the current target current control strategy, determine the inductor current duration corresponding to the carrier cycle, the on time of one carrier cycle, the off time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value; Based on the average current determination sub-strategy in the current target current control strategy, determine the current average current corresponding to the first inductor current ADC sampling value, the inductor current duration and the carrier period; The formula corresponding to the inductor current duration determination sub-strategy is: , where T len represents the duration of the inductor current in one carrier cycle, T on Indicates the opening time of a carrier cycle, i L_up represents the first inductor current ADC sampling value and i L_dn Represents the second inductor current ADC sampling value, T s Represents one carrier cycle of the sampled signal; The formula corresponding to the average current determination sub-strategy is: , where i L_avg Indicates the current average current.

2. The method according to claim 1, characterized in that The obtaining of a current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value includes: Obtaining an absolute value of a first current sampling value corresponding to the first inductor current ADC sampling value, and obtaining an absolute value of a second current sampling value corresponding to the second inductor current ADC sampling value; The current difference is determined based on a difference between an absolute value of the first current sampling value and an absolute value of the second current sampling value.

3. The method according to claim 2, characterized in that The determining of a target current value interval of the current difference value in a plurality of preset current value intervals includes: If it is determined that the current current difference belongs to the first preset current value interval among the multiple preset current value intervals, the first preset current value interval is used as the target current value interval; wherein the first preset current value interval is (-∞, Δi1), and Δi1 is a first preset current threshold.

4. The method according to claim 3, characterized in that The determining the current average current according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value includes: The first inductor current ADC sampling value is selected from the first inductor current ADC sampling value and the second inductor current ADC sampling value based on the current target current control strategy and is used as the current average current.

5. The method according to claim 2, characterized in that: The determining of a target current value interval of the current difference value in a plurality of preset current value intervals includes: If it is determined that the current current difference belongs to the second preset current value interval among the multiple preset current value intervals, the second preset current value interval is used as the target current value interval; wherein the second preset current value interval is (Δi2, +∞), and Δi2 is a second preset current threshold.

6. A PFC current feedback control device based on average current detection, characterized in that: include: A current ADC sampling unit, used to obtain a first inductor current ADC sampling value at a carrier zero point and a second inductor current ADC sampling value at a carrier peak; a target current value interval acquisition unit, configured to acquire a current current difference between the first inductor current ADC sampling value and the second inductor current ADC sampling value, and determine a target current value interval of the current current difference in a plurality of preset current value intervals; a current average current acquisition unit, configured to acquire a current target current control strategy corresponding to the target current value interval, determine a current average current according to the current target current control strategy, the first inductor current ADC sampling value, and the second inductor current ADC sampling value, and use the current average current as a feedback amount of a target control loop; The current average current acquisition unit is specifically used for: Obtaining a carrier cycle, an on-time of a carrier cycle, and an off-time of a carrier cycle corresponding to the first inductor current ADC sampling value and the second inductor current ADC sampling value; wherein the on-time of a carrier cycle+the off-time of a carrier cycle=the carrier cycle; Based on the inductor current duration determination sub-strategy preset in the current target current control strategy, determine the inductor current duration corresponding to the carrier cycle, the on time of one carrier cycle, the off time of one carrier cycle, the first inductor current ADC sampling value, and the second inductor current ADC sampling value; Based on the average current determination sub-strategy in the current target current control strategy, determine the current average current corresponding to the first inductor current ADC sampling value, the inductor current duration and the carrier period; The formula corresponding to the inductor current duration determination sub-strategy is: , where T len represents the duration of the inductor current in one carrier cycle, T on Indicates the opening time of a carrier cycle, i L_up represents the first inductor current ADC sampling value and i L_dn Represents the second inductor current ADC sampling value, T s Represents one carrier cycle of the sampled signal; The formula corresponding to the average current determination sub-strategy is: , where i L_avg Indicates the current average current.

7. A computer device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the computer program, the PFC current feedback control method based on average current detection according to any one of claims 1 to 5 is implemented.

8. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, wherein the computer program includes program instructions, and when the program instructions are executed by a processor, the PFC current feedback control method based on average current detection according to any one of claims 1 to 5 can be implemented.

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