Power converter drive control method, power converter and chip

Abstract

The application relates to a power converter driving control method, a power converter and a chip. The method is used in a controller in a power converter, a direct current conversion circuit in the power converter is connected with a photovoltaic module, current working condition data of the photovoltaic module is acquired, a target dead time control table corresponding to the current working condition data is determined from a plurality of preset dead time control tables according to the current working condition data, wherein the dead time control table comprises dead times corresponding to respective switching periods in a power frequency period, and each dead time control table corresponds to different test working condition data of the photovoltaic module; and working driving signals of switching tubes in the direct current side conversion circuit are generated based on the target dead time control table. The above method can reduce the realization of dynamic dead time control, reduce the conduction of body diodes and reduce the turn-on loss.

Description

[0001] Cross-references to related applications

[0002] This application claims the benefit of U.S. Patent Application No. 19 / 530,333, filed February 4, 2026. The entire contents of the above-cited application are hereby incorporated herein by reference. Technical Field

[0003] This application relates to the field of power conversion technology, and in particular to a power converter drive control method, a power converter, and a chip. Background Technology

[0004] In a power converter, two switches located in the same bridge arm cannot be turned on simultaneously, otherwise the bridge arm will short-circuit. Because the turn-off and turn-on of a switch are not instantaneous, a dead time is added at the complementary switching moments of the two switches in the same bridge arm to avoid short-circuiting of the bridge arm circuit during switching.

[0005] However, a fixed dead time cannot guarantee a perfect commutation time under different operating conditions, causing the freewheeling diode or body diode to conduct, resulting in additional conduction losses.

[0006] Therefore, it is necessary to provide a power converter drive control method, power converter, and chip that can reduce the consumption of computing resources to address the above-mentioned technical problems. Summary of the Invention

[0007] Firstly, a power converter drive control method is provided. The method is used in a controller within a power converter, wherein the DC-side conversion circuit of the power converter is connected to a photovoltaic module. The method includes:

[0008] Obtain current operating condition data for photovoltaic modules;

[0009] Based on the current operating condition data, the target dead time control table is determined by searching through multiple preset dead time control tables. The dead time control table includes the dead time corresponding to each switching cycle within one power frequency cycle, and each dead time control table corresponds to different test operating condition data of the photovoltaic module.

[0010] The operating drive signals for each switch in the DC-side converter circuit are generated based on the target dead-time control table.

[0011] In one embodiment, the dead-time control table is obtained in the following manner:

[0012] For each test condition data, under the condition that the photovoltaic module operates according to the test condition data, obtain the off measurement duration and / or turn-on measurement duration corresponding to each switching cycle of each switch in the DC-side conversion circuit within one power frequency cycle.

[0013] Based on the turn-off measurement duration and / or turn-on measurement duration of each switch in each switching cycle, a dead time control table corresponding to the test condition data is obtained.

[0014] In one embodiment, based on the turn-off measurement duration corresponding to each switching cycle, a dead-time control table corresponding to the test condition data is obtained, including:

[0015] Obtain the device deviation parameters corresponding to the switching transistor;

[0016] Based on the device deviation parameters, the turn-off measurement duration corresponding to each switching cycle is compensated to obtain the target turn-off duration corresponding to each switching cycle.

[0017] Based on the target turn-off duration corresponding to each switching cycle, a dead time control table corresponding to the test condition data is obtained.

[0018] In one embodiment, a power frequency cycle includes multiple control time periods, each control time period includes multiple switching cycles, and the dead time control table includes the dead time corresponding to each control time period.

[0019] Based on the target turn-off duration corresponding to each switching cycle, a dead-time control table corresponding to the test condition data is obtained, including:

[0020] For each control time period, the dead time corresponding to each control time period in the dead time control table is determined based on the maximum value among the target off-times corresponding to the multiple switching cycles included in the control time period.

[0021] In one embodiment, a search process is performed from multiple preset dead-time control tables based on the current operating condition data to determine the target dead-time control table corresponding to the current operating condition data, including:

[0022] Determine the test condition data with the smallest difference from the current test condition data from different test condition data;

[0023] The dead time control table corresponding to the test condition data with the smallest difference is determined as the target dead time control table.

[0024] In one embodiment, the operating drive signals for each switch in the DC-side converter circuit are generated based on the target dead-time control table, including:

[0025] Obtain the AC output voltage of the power converter;

[0026] Determine the current phase within the power frequency cycle based on the AC output voltage;

[0027] Based on the current phase and target dead-time control table, generate the working drive signal.

[0028] In a second aspect, a power converter is provided, wherein a DC-side conversion circuit in the power converter is connected to a photovoltaic module, and the power converter includes a controller for performing the steps of the method described in the first aspect.

[0029] In one embodiment, the controller includes a microcontroller and a programmable logic device, wherein,

[0030] The microcontroller is used to acquire the current operating condition data of the photovoltaic module, and to search and process multiple preset dead time control tables based on the current operating condition data to determine the target dead time control table corresponding to the current operating condition data.

[0031] Programmable logic devices are used to generate operating drive signals for each switch in the DC-side converter circuit based on the target dead-time control table;

[0032] Alternatively, the controller may be a programmable logic device.

[0033] Thirdly, a chip is provided, including a microcontroller, the chip being disposed in a power converter, the DC-side conversion circuit in the power converter being connected to a photovoltaic module, and the power converter also including a programmable logic device.

[0034] The microcontroller is used to acquire the current operating condition data of the photovoltaic module; based on the current operating condition data, it searches and processes multiple preset dead time control tables to determine the target dead time control table corresponding to the current operating condition data, and sends the target dead time control table to the programmable logic device (PLD), so that the PLD can generate the working drive signals of each switch in the DC-side converter circuit based on the target dead time control table. Each dead time control table corresponds to different test operating condition data of the photovoltaic module, and the dead time control table includes the dead time corresponding to each switching cycle within one power frequency cycle.

[0035] Fourthly, a chip is provided, including a programmable logic device, the chip being disposed in a power converter, wherein a DC-side conversion circuit in the power converter is connected to a photovoltaic module, and the programmable logic device is used to perform the steps of the method described in the first aspect.

[0036] The aforementioned power converter drive control method, power converter, and chip; wherein the method is used in the controller of the power converter, the DC-DC conversion circuit of the power converter is connected to the photovoltaic module, by acquiring the current operating condition data of the photovoltaic module, and searching through multiple preset dead-time control tables according to the current operating condition data to determine the target dead-time control table corresponding to the current operating condition data, wherein the dead-time control table includes the dead time corresponding to each switching cycle within one power frequency cycle, and each dead-time control table corresponds to different test operating condition data of the photovoltaic module; the working drive signal of each switch in the DC-side conversion circuit is generated based on the target dead-time control table; on the one hand, given the operating condition of the DC-side photovoltaic module, the rate of decrease of the turn-on voltage and the rate of increase of the turn-off voltage of the switch are related to the amplitude of the AC-side output voltage; on the other hand, when the amplitude of the AC-side output voltage is the same, the rate of decrease of the turn-on voltage of the switch is related to the amplitude of the AC-side output voltage. The rate of decrease and the rate of rise of the turn-off voltage are affected by the output operating conditions of the photovoltaic module. The above method pre-sets dead-time control tables corresponding to different test operating conditions. Each dead-time control table includes the dead time corresponding to each switching cycle in the next power frequency cycle of the corresponding test operating condition data. In practical applications, the target dead-time table corresponding to the current operating condition data of the photovoltaic module is obtained by searching and processing the data. The table includes the dead time corresponding to each switching cycle that matches the current operating condition data in one power frequency cycle. This realizes dynamic dead-time control according to different operating conditions of the photovoltaic module, reduces the conduction of the body diode, and reduces the turn-on loss. At the same time, it avoids the problem of excessive computing resources caused by the need to sample the voltage or current of the switching tube in real time and calculate the dead-time compensation value for each switching cycle in related technologies. The above power converter drive control method can reduce the computing resources occupied by dynamic dead-time control. Attached Figure Description

[0037] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0038] Figure 1 This is a schematic diagram of the power converter in one embodiment;

[0039] Figure 2 This is a schematic diagram of the power converter in another embodiment;

[0040] Figure 3 This is a flowchart illustrating a power converter drive control method in one embodiment;

[0041] Figure 4 This is a flowchart illustrating the process of obtaining the dead time control table in one embodiment;

[0042] Figure 5 This is a timing diagram illustrating the complementary switching process of two switching transistors in one embodiment;

[0043] Figure 6 This is a flowchart illustrating the steps for obtaining the dead-time control table in another embodiment;

[0044] Figure 7 This is a schematic diagram illustrating how a switching cycle is divided into multiple control time periods in one embodiment.

[0045] Figure 8 This is a flowchart illustrating the steps for generating the working drive signal in one embodiment;

[0046] Figure 9 This is a flowchart illustrating the power converter drive control method in another embodiment.

[0047] Unless otherwise stated, the numbers and symbols corresponding in the different figures generally refer to the corresponding parts. The figures are drawn to clearly illustrate relevant aspects of the embodiments and are not necessarily drawn to scale. Detailed Implementation

[0048] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0049] It should be noted that the terms "first," "second," etc., used in this application can be used to describe various elements, but these elements are not limited by these terms. These terms are only used to distinguish the first element from the second element. The terms "comprising" and "having," and any variations thereof, used in this application, are intended to cover non-exclusive inclusion. The term "multiple" used in this application refers to two or more. The term "and / or" used in this application refers to one of the embodiments, or any combination of multiple embodiments.

[0050] It is understood that the term "connection" in the following embodiments should be understood as "electrical connection," "communication connection," etc., if the connected circuits, modules, units, etc., have electrical signal or data transmission with each other.

[0051] It is understood that the term "based on" as used in this application is used to describe one or more factors that influence the determination, but does not exclude other factors that may influence the determination. For example, the phrase "determine A based on B" means that the determination of A can be based entirely or at least partially on factor B. That is, B is a factor that influences the determination of A, but does not exclude the fact that the determination of A is also based on C.

[0052] When used herein, the singular forms of “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “comprising / including” or “having,” etc., specify the presence of the stated features, wholes, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0053] The power converter drive control method provided in this application embodiment can be applied to, for example, Figure 1 The power converter shown includes a DC-side conversion circuit 100 comprising two interconnected switches Q1 and Q2. During normal operation, switches Q1 and Q2 are complementary in conduction. The DC-side conversion circuit 100 is connected to the photovoltaic module 200 and, via a transformer TS, is connected to the AC-side conversion circuit. The power converter also includes a controller (not shown), which is connected to each switch in the DC-side conversion circuit.

[0054] In other embodiments, the DC-side conversion circuit in the power converter involved in the provided power converter drive control method is a full-bridge circuit including two bridge arms, such as... Figure 2 As shown, one arm of the full-bridge circuit includes switches Q1 and Q2 connected in series, and the other arm includes switches Q3 and Q4 connected in series. During normal operation, switches Q1 and Q2 are complementary in conduction, and switches Q3 and Q4 are complementary in conduction. The conduction timing of switches Q1 and Q2 is the same.

[0055] In some embodiments, the switching transistor may also be referred to as a power transistor, or a switching device, or a power device. The switching devices involved in the embodiments of this application may be implemented using, but are not limited to, MOS transistors (Metal-Oxide-Semiconductor Field-Effect Transistors) or IGBTs (Insulated Gate Bipolar Transistors). Unless otherwise specified, this application does not limit the specific type and model of the switching device.

[0056] In the field of power conversion technology, two switches located in the same bridge arm of a power converter cannot be turned on simultaneously, otherwise the bridge arm will short-circuit. Because the turn-off and turn-on of a switch are not instantaneous, a dead time is added at the complementary switching moments of the two switches in the same bridge arm to avoid short-circuiting of the bridge arm circuit during switching. However, a fixed dead time cannot guarantee perfect commutation timing under different operating conditions, causing the freewheeling diode or body diode to conduct, resulting in additional turn-on losses.

[0057] Therefore, dynamic dead time can be used to achieve power converter drive control. By using the transient waveforms of the switching current or voltage, the actual turn-on and turn-off times are obtained, the actual dead time compensation value required for each bridge arm circuit is calculated, and the actual dead time compensation value is inserted into the fixed dead time to achieve dynamic dead time control. However, the above method requires a high sampling frequency and high computing power, resulting in high computational resource consumption. This application provides a power converter drive control method, a power converter, and a chip through the following embodiments to reduce the consumption of computational resources.

[0058] In one exemplary embodiment, please refer to Figure 3 This paper provides a power converter drive control method for use in the controller of a power converter, wherein the DC-side conversion circuit of the power converter is connected to a photovoltaic module. Figure 3 As shown, the method includes steps 302 to 306, wherein:

[0059] Step 302: Obtain the current operating condition data of the photovoltaic module.

[0060] The current operating condition data refers to the photovoltaic module operating condition data acquired when the dead time needs to be updated to determine the current load status of the power converter. For example, the photovoltaic module operating condition data includes one or more of the photovoltaic module's output power, output voltage, and output current.

[0061] For example, the current operating condition data of the photovoltaic modules is acquired at preset time intervals to determine whether the dead-time control table needs to be updated. For instance, the current operating condition data of the photovoltaic modules is acquired every hour or 15 minutes. For example, if the current operating condition data differs significantly from the previously acquired data, subsequent steps 306 and 308 are executed to switch the target dead-time control table; if the current operating condition data differs only slightly from the previously acquired data, subsequent steps 306 and 308 are not executed, and the currently used target dead-time control table remains unchanged.

[0062] Step 306: Based on the current operating condition data, search and process multiple preset dead time control tables to determine the target dead time control table corresponding to the current operating condition data.

[0063] The dead time control table includes the dead time corresponding to each switching cycle within one power frequency cycle. The power frequency is 50Hz (Hertz) or 60Hz, and the corresponding power frequency cycle is 50ms (milliseconds) or 1 / 60s (seconds).

[0064] For example, the power frequency cycle is 20ms, and the switching cycle is 100kHz (kilohertz), with one power frequency cycle corresponding to 2000 switching cycles. Each switching cycle includes a set of dead times corresponding to one bridge arm circuit. Each set of dead times includes two dead times: one corresponding to the switch from the upper transistor to the lower transistor, and the other corresponding to the switch from the lower transistor to the upper transistor. If the DC-side converter circuit includes two bridge arm circuits, each switching cycle includes two sets of dead times corresponding to each of the two bridge arm circuits. Please refer to Table 1 for a tabular example of the two dead time control tables. The dead times in Table 1 are merely examples and are not intended to limit the dead times in this embodiment of the application.

[0065] Table 1. Example of a two-dead-time control table

[0066]

[0067] The dead-time control tables correspond to different test conditions for photovoltaic modules. For power semiconductors, the voltage rise and fall rates of devices vary under different operating conditions. In power converters, the rate of decrease of the turn-on voltage and the rate of increase of the turn-off voltage of the switching transistor are related to the output conditions of the photovoltaic module. Given certain operating conditions, the rate of decrease of the turn-on voltage and the rate of increase of the turn-off voltage of the switching transistor are also related to the amplitude of the AC output voltage. These different rates require different dead times to reduce the conduction of the body diode, reduce turn-on losses, and improve system efficiency.

[0068] In this embodiment, the dead time corresponding to each switching cycle in a power frequency cycle is obtained in advance under different test operating conditions, and a dead time control table corresponding to the test operating conditions is obtained and stored in the storage unit in the controller. The test operating conditions are used as the lookup index for the corresponding dead time control table. When the power converter is connected to the grid, the test operating conditions data that match the current operating conditions data are determined from multiple test operating conditions data according to the current operating conditions data of the photovoltaic module. The dead time control table corresponding to the test operating conditions data is determined as the target dead time control table.

[0069] In one possible implementation, the operating condition data includes the output voltage of the photovoltaic module; determining the target dead time control table corresponding to the current operating condition data by searching through multiple preset dead time control tables based on the current operating condition data includes: determining the target dead time control table corresponding to the current output voltage by searching through multiple preset dead time control tables based on the current output voltage.

[0070] In one possible implementation, when the operating condition data includes either the output current or the output power of the photovoltaic module, a search is performed from multiple preset dead-time control tables based on the current operating condition data to determine the target dead-time control table corresponding to the current operating condition data. This method is similar to the search method in the previous implementation where the operating condition data is the output voltage, and will not be described again here.

[0071] In one possible implementation, the operating condition data includes two or three of the photovoltaic module's output current, output voltage, and output power. Correspondingly, the index of the dead-time control table is two-dimensional or three-dimensional. For example, the operating condition data includes the photovoltaic module's output current and output voltage. The process of determining the target dead-time control table corresponding to the current operating condition data by searching through multiple preset dead-time control tables includes: searching through multiple preset dead-time control tables based on the current output current to determine at least one candidate dead-time control table corresponding to the current output current; and searching through the at least one candidate dead-time control table based on the current output voltage to determine the target dead-time control table corresponding to the current operating condition data.

[0072] In other example cases where the operating data includes two or three of the photovoltaic module's output current, output voltage, and output power, the process for determining the target dead-time control table is similar to that in the previous example where the operating data included the photovoltaic module's output current and output voltage, and will not be repeated here.

[0073] Step 306: Generate the operating drive signals for each switch in the DC-side converter circuit based on the target dead-time control table.

[0074] Specifically, based on the dead time corresponding to each switching cycle in the target dead time control table, the turn-off and turn-on times of the upper and lower switches in each switching cycle are determined, thereby generating a pulse width modulation wave (PWM) signal to drive each switch, i.e., the working drive signal. The PWM signal is output to the corresponding switch to realize that each switch alternately turns on and off according to the dead time set in the target dead time control table in each switching cycle.

[0075] The power converter drive control method provided in the above embodiments is used in the controller of a power converter. The DC-DC conversion circuit in the power converter is connected to the photovoltaic module. By acquiring the current operating condition data of the photovoltaic module, the method searches through multiple preset dead-time control tables based on the current operating condition data to determine the target dead-time control table corresponding to the current operating condition data. The dead-time control table includes the dead time corresponding to each switching cycle within one power frequency cycle, and each dead-time control table corresponds to different test operating condition data of the photovoltaic module. Based on the target dead-time control table, the method generates operating drive signals for each switch in the DC-DC conversion circuit. On the one hand, given the operating conditions of the photovoltaic module, the rate of decrease of the turn-on voltage and the rate of increase of the turn-off voltage of the switch are related to the amplitude of the AC-side output voltage. On the other hand, when the amplitude of the AC-side output voltage is the same, the rate of decrease of the turn-on voltage and the rate of increase of the turn-off voltage of the switch are related to the amplitude of the AC-side output voltage. The rise rate is affected by the output operating conditions of the photovoltaic module. The above embodiment pre-sets dead time control tables corresponding to different test operating condition data. Each dead time control table includes the dead time corresponding to each switching cycle in the next power frequency cycle of the corresponding test operating condition data. In actual application, the target dead time table corresponding to the current operating condition data of the photovoltaic module is obtained by searching and processing according to the current operating condition data. The table includes the dead time corresponding to each switching cycle that matches the current operating condition data in one power frequency cycle. This realizes dynamic dead time control according to different operating conditions of the photovoltaic module, reduces the conduction of the body diode, and reduces the turn-on loss. At the same time, it avoids the problem of excessive computing resources caused by the need to sample the voltage or current of the switching tube in real time and calculate the dead time compensation value for each switching cycle in related technologies. The power converter drive control method provided in this embodiment can reduce the computing resource consumption of dynamic dead time control.

[0076] In one exemplary embodiment, based on Figure 3 The illustrated embodiment provides a power converter drive control method involving the acquisition process of the dead-time control table. Please refer to... Figure 4 For each test condition data, the corresponding dead time control table is obtained through steps 402 and 404.

[0077] Step 402: With the photovoltaic module operating according to the test condition data, obtain the off-time and / or on-time measurement durations of each switching transistor in the DC-side conversion circuit within one power frequency cycle.

[0078] In one possible implementation, the off-time measurement duration of each switching transistor in the DC-side converter circuit is obtained for each switching cycle within one power frequency cycle.

[0079] For example, a MOSFET is used as the switching transistor. The turn-off measurement time is obtained by measuring the time required for the drain-source voltage of the switching transistor to rise from a low voltage to a high voltage. Here, the low voltage refers to the drain-source voltage when the switching transistor is turned on, and the high voltage refers to the drain-source voltage when the switching transistor is turned off.

[0080] In one possible implementation, the turn-on measurement duration of each switching transistor in the DC-side converter circuit is obtained for each switching cycle within one power frequency cycle.

[0081] For example, a MOSFET is used as the switching transistor. The turn-on measurement time is obtained by measuring the time required for the drain-source voltage of the switching transistor to drop from a high voltage to a low voltage.

[0082] In one possible implementation, the off-time and on-time measurements of each switching transistor in the DC-side converter circuit are obtained for each switching cycle within one power frequency cycle.

[0083] Step 404: Based on the turn-off measurement duration and / or turn-on measurement duration corresponding to each switching cycle, obtain the dead time control table corresponding to the test condition data.

[0084] In one possible implementation, a dead time control table corresponding to the test condition data is obtained based on the turn-off measurement duration of each switch in each switching cycle.

[0085] For example, by adding a safety margin duration to the turn-off measurement duration for each switching transistor in each switching cycle, the dead time for each switching cycle is obtained, resulting in a dead time control table. Adding a safety margin to the turn-off measurement duration to obtain the dead time avoids signal transmission delays caused by PCB (Printed Circuit Board) wiring, parasitic capacitance, or parasitic inductance, or inaccurate dead time due to signal transmission issues in the drive circuit.

[0086] Please refer to Figure 5This is an example of a timing diagram illustrating the complementary switching process of two switching transistors; where the turn-off duration corresponds to the time it takes for one switching transistor in the bridge arm circuit to switch from the on state to the off state, and the turn-on duration corresponds to the time it takes for the other switching transistor in the same bridge arm circuit to switch from the off state to the on state; dead time refers to the time between the turn-off time of one switching transistor in the same bridge arm circuit and the turn-on time of the next switching transistor. For example... Figure 5 As shown in this example, the dead time is the turn-off time of the previous switch plus a certain safety margin.

[0087] For example, the safety margin duration ranges from 10 ns to 50 ns. The value of the safety margin duration may vary depending on the type of switching transistor.

[0088] In one possible implementation, a dead time control table corresponding to the test condition data is obtained based on the turn-off measurement duration and turn-on measurement duration of each switch in each switching cycle.

[0089] Specifically, the turn-off measurement duration is referenced and corrected based on the turn-on measurement duration of the switching transistor to obtain the target turn-off duration of the switching cycle, and the dead time control table corresponding to the test condition data is obtained.

[0090] In one possible implementation, based on the turn-on measurement duration of each switch in each switching cycle, the target turn-off duration of each switch in each switching cycle is derived, thus obtaining the dead time control table corresponding to the test condition data.

[0091] The power converter drive control method provided in the above embodiments measures the turn-off measurement duration and / or turn-on measurement duration of the switching transistor in each switching cycle of a power frequency cycle under different operating conditions. Based on the measured data, the dead time corresponding to each switching cycle is determined, thereby obtaining the dead time control table corresponding to each test operating condition data, thus improving the accuracy of the dead time control table.

[0092] In one exemplary embodiment, please refer to Figure 6 The process of obtaining the dead time control table corresponding to the test condition data based on the turn-off measurement duration corresponding to each switching cycle includes steps 602 to 606, wherein:

[0093] Step 602: Obtain the device deviation parameters corresponding to the switching transistor.

[0094] Device deviation parameters mainly refer to the fact that even for the same type of MOSFET or IGBT, differences in manufacturing processes, operating temperatures, voltage and current conditions can lead to variations in switching characteristic parameters and consequently, differences in turn-off times. The type of device deviation parameter is determined based on the different types of switching transistors, application environments, and manufacturers.

[0095] For example, device deviation parameters include switching time deviation parameters; the process of obtaining the device deviation parameters corresponding to the switching transistor includes: obtaining the maximum and minimum switching times of the switching transistor, and using the difference between the maximum and minimum switching times as the switching time deviation parameter. For example, the maximum and minimum switching times of the switching transistor can be obtained from the switching transistor's manufacturer's datasheet.

[0096] For example, the device deviation parameter includes the gate charge deviation parameter; the process of obtaining the device deviation parameter corresponding to the switch includes: obtaining the typical value and the maximum value of the gate charge of the switch, determining the charge difference between the typical value of the gate charge and the maximum value of the gate charge, and using the ratio between the charge difference and the typical value of the gate charge as the gate charge deviation parameter.

[0097] For example, the device deviation parameters include parasitic capacitance deviation parameters; the process of obtaining the device deviation parameters corresponding to the switching transistor includes: obtaining the typical value and the maximum value of the parasitic capacitance of the switching transistor, determining the capacitance difference between the maximum value and the typical value of the parasitic capacitance, and using the ratio between the capacitance difference and the typical value of the parasitic capacitance as the parasitic capacitance deviation parameter.

[0098] Step 604: Based on the device deviation parameters, the turn-off measurement duration corresponding to each switching cycle is compensated to obtain the target turn-off duration corresponding to each switching cycle.

[0099] The target turn-off time obtained by compensating the turn-off measurement time based on the device deviation parameters can make up for the inconsistency in the turn-off time caused by the device deviation parameters.

[0100] For example, the device deviation parameters include the switching time deviation parameters. Correspondingly, the target shutdown duration is obtained by adding the switching time deviation parameters to the shutdown measurement duration.

[0101] For example, the device deviation parameter includes the gate charge deviation parameter. Correspondingly, the turn-off measurement duration is amplified according to the gate charge deviation parameter to obtain the target turn-off duration. For instance, if the gate charge deviation parameter is 20%, the turn-off measurement duration is multiplied by 120% to obtain the target turn-off duration.

[0102] For example, the device deviation parameter includes the parasitic capacitance deviation parameter. Correspondingly, the turn-off measurement time is amplified according to the parasitic capacitance deviation parameter to obtain the target turn-off time. For instance, if the parasitic capacitance deviation parameter is 10%, then the turn-off measurement time is multiplied by 110% to obtain the target turn-off time.

[0103] Step 606: Based on the target off-time corresponding to each switching cycle, obtain the dead time control table corresponding to the test condition data.

[0104] For example, the target turn-off duration corresponding to each switching cycle is used as the dead time corresponding to each switching cycle to obtain the dead time control table corresponding to the test condition data.

[0105] For example, the target turn-off time corresponding to each switching cycle is added to the safety margin time to obtain the dead time corresponding to each switching cycle, and the dead time control table corresponding to the test condition data is obtained.

[0106] For example, please refer to Figure 7 One power frequency cycle includes multiple control time periods Δt, each control time period includes multiple switching cycles, and the dead time control table includes the dead time corresponding to each control time period; that is, the dead time corresponding to each switching cycle within each control time period is the same.

[0107] In this example, a dead-time control table corresponding to the test output power is obtained based on the target off-time corresponding to each switching cycle. This includes: for each control time period, determining the dead-time corresponding to the control time period based on the maximum value among the target off-times corresponding to the multiple switching cycles included in the control time period. Please refer to Table 2 for an example of the process of determining the dead-time corresponding to the control time period based on the maximum value among the target off-times corresponding to each switching cycle. The dead-time in Table 2 is only a formal example and is not intended to limit the dead-time in this embodiment of the application. Table 2 is an intermediate table in the testing process. After calculating the dead-time corresponding to the control time period, the dead-time control table stored in the controller does not have a "target off-time" column.

[0108] Table 2. Example of the process for determining the dead time corresponding to the control time period.

[0109]

[0110] For example, adding the maximum value of the target shutdown duration to the safety margin duration yields the dead time corresponding to that control period. Alternatively, the maximum value of the target shutdown duration can be used as the dead time corresponding to that control period.

[0111] In one possible implementation, the length of each control time period is the same, that is, one power frequency cycle is divided into multiple control intervals.

[0112] In one possible implementation, the length of the control time period corresponding to the peak and trough positions is shorter than the length of the control time period corresponding to the zero-crossing position. That is, the control time period is divided more densely at the peak and trough positions where the AC current amplitude is relatively large, and the control time period is divided relatively sparsely at the zero-crossing position.

[0113] In this example, the switching cycles corresponding to a power frequency cycle are divided into multiple control time periods according to timing. Within a control time period, the load current of the switching transistors is similar, and the corresponding target turn-off times are also similar. Using the maximum value within the target turn-off time of this control time period ensures the safety and reliability of the dead time within that control time period, and also makes the dead time of each switching cycle within the same control time period conform to the load current of the switching transistors as much as possible. Furthermore, dividing a power frequency cycle into multiple control time periods in this example, with each switching cycle within the same control time period corresponding to the same dead time, reduces the size of the dead time control table and the storage resource consumption of the controller. Additionally, when generating the operating drive signals for each switching transistor in the DC-side converter circuit based on the target dead time control table, the operating drive signals have the same dead time for each switching cycle within the same control time period, reducing the computational resource consumption during drive signal generation.

[0114] In one exemplary embodiment, based on Figure 3 The embodiment shown illustrates a power converter drive control method that involves searching through multiple preset dead-time control tables based on current operating condition data to determine a target dead-time control table corresponding to the current operating condition data. This process includes steps A1 and A2, wherein:

[0115] Step A1: Determine the test condition data with the smallest difference from the current test condition data from different test condition data.

[0116] Step A2: Determine the dead time control table corresponding to the test condition data with the smallest difference as the target dead time control table.

[0117] Thus, based on the difference between the operating condition data, the dead time control table corresponding to the test operating condition data with the smallest difference is determined as the target dead time control table. The calculation process is simple and reduces the consumption of computing resources.

[0118] In one exemplary embodiment, based on Figure 3The embodiment shown illustrates a power converter drive control method that involves generating operating drive signals for each switch in the DC-side full-bridge circuit based on a target dead-time control table. Please refer to... Figure 8 The process is as follows:

[0119] Step 802: Obtain the AC output voltage of the power converter.

[0120] For example, the AC output voltage signal of the power converter is obtained through a sampling circuit.

[0121] Step 804: Determine the current phase in the power frequency cycle based on the AC output voltage.

[0122] For example, the current phase in the power frequency cycle is determined based on the voltage amplitude and sign at the current moment.

[0123] Step 806: Generate the working drive signal based on the current phase and the target dead time control table.

[0124] Since the change pattern of dead time is synchronized with the change of AC output voltage, the target dead time control table can be synchronized with the AC output voltage based on the current phase to generate the working drive signal.

[0125] For example, based on the current phase and the switching frequency of the switching transistor, the current phase is determined to be in which switching cycle of a power frequency cycle. Then, starting from that switching cycle, the switching transistor is inserted into the turn-on and turn-off sequence according to the dead time in the target dead time control table to generate the working drive signal.

[0126] For example, the starting zero-crossing time of the next switching cycle is determined based on the current phase. At the starting zero-crossing time, the dead time in the target dead time control table is inserted into the turn-on and turn-off sequence of the switching transistor to generate the working drive signal.

[0127] The power converter drive control method provided in this embodiment determines the phase of the current time within the current power frequency cycle through the AC output voltage, thereby synchronizing the power frequency cycle and the target dead time control table. This method is independent of other control functions in the system and facilitates implementation based on the computing power allocation of the controller in the power converter. For example, the power converter drive control method provided in this embodiment can be implemented in programmable logic devices such as CPLDs (Complex Programmable Logic Devices) or FPGAs (Field-Programmable Gate Arrays), without occupying the computing resources of the MCU (Microcontroller Unit).

[0128] In one exemplary embodiment, please refer to Figure 9 This paper provides a power converter drive control method for use in the controller of a power converter, wherein the DC-side conversion circuit of the power converter is connected to a photovoltaic module. Figure 9 As shown, the method includes steps 902 to 916, wherein:

[0129] Step 902: For each test condition data, under the condition that the photovoltaic module operates according to the test condition data, obtain the turn-off measurement duration corresponding to each switching cycle of each switch in the DC-side conversion circuit within one power frequency cycle.

[0130] Step 904: Obtain the device deviation parameters corresponding to the switching transistor.

[0131] Step 906: Based on the device deviation parameters, the turn-off measurement duration corresponding to each switching cycle is compensated to obtain the target turn-off duration corresponding to each switching cycle.

[0132] Step 908: For each control time period, determine the dead time corresponding to each control time period in the dead time control table based on the maximum value among the target off-times corresponding to the multiple switching cycles included in the control time period. Here, one power frequency cycle includes multiple control time periods, each control time period includes multiple switching cycles, and the dead time control table includes the dead time corresponding to each control time period.

[0133] Step 910: Obtain the current operating condition data of the photovoltaic modules.

[0134] Step 912: Determine the test condition data with the smallest difference from the current test condition data from different test condition data.

[0135] Step 914: Determine the dead time control table corresponding to the test condition data with the smallest difference as the target dead time control table.

[0136] Step 916: Generate the operating drive signals for each switch in the DC-side converter circuit based on the target dead-time control table.

[0137] Optionally, the process of generating the operating drive signal for each switch in the DC-side converter circuit based on the target dead-time control table includes: acquiring the AC output voltage of the power converter; determining the current phase in the power frequency cycle based on the AC output voltage; and generating the operating drive signal based on the current phase and the target dead-time control table.

[0138] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages in other steps. It is understood that the steps in different embodiments can be freely combined as needed, and all non-contradictory solutions formed by such combinations are within the scope of protection of this application.

[0139] It is understood that the term "based on" as used in this application is used to describe one or more factors that influence the determination, but does not exclude other factors that may influence the determination. For example, the phrase "determine A based on B" means that the determination of A can be based entirely or at least partially on factor B. That is, B is a factor that influences the determination of A, but does not exclude the fact that the determination of A is also based on C.

[0140] In one embodiment, a power converter is provided. For example... Figure 1 and Figure 2 The DC-side conversion circuit in the power converter is connected to the photovoltaic module, and the power converter includes a controller ( Figure 1 and Figure 2 (Not shown in the diagram), the controller is connected to each switch in the DC-side conversion circuit and is used to execute the steps provided in the above method embodiments.

[0141] In an exemplary embodiment, the controller includes a microcontroller and a programmable logic device, wherein the microcontroller is used to acquire the current operating condition data of the photovoltaic module, and perform lookup processing from multiple preset dead-time control tables based on the current operating condition data to determine a target dead-time control table corresponding to the current operating condition data; the programmable logic device is used to generate operating drive signals for each switching transistor in the DC-side conversion circuit based on the target dead-time control table.

[0142] In one exemplary embodiment, the controller is a programmable logic device.

[0143] In one embodiment, a chip is provided, including a microcontroller, which is configured to be disposed in a power converter. The power converter has a DC-side conversion circuit connected to a photovoltaic module. The power converter also includes a programmable logic device. The microcontroller is configured to acquire current operating condition data of the photovoltaic module; perform lookup processing from multiple preset dead-time control tables based on the current operating condition data to determine a target dead-time control table corresponding to the current operating condition data; and send the target dead-time control table to the programmable logic device so that the programmable logic device can generate operating drive signals for each switch in the DC-side conversion circuit based on the target dead-time control table. Each dead-time control table corresponds to different test operating condition data of the photovoltaic module, and the dead-time control table includes the dead time corresponding to each switching cycle within one power frequency cycle.

[0144] In one embodiment, a chip is provided, including a programmable logic device, the chip being disposed in a power converter, the DC-side conversion circuit in the power converter being connected to a photovoltaic module, the programmable logic device being used to perform the steps provided in the above method embodiments.

[0145] In one embodiment, a chip is provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0146] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0147] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium, and when executed, it can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0148] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0149] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A power converter drive control method, characterized in that, The method is used in a controller of a power converter, wherein the DC-side conversion circuit of the power converter is connected to a photovoltaic module, and the method includes: Obtain the current operating condition data of the photovoltaic module; Based on the current operating condition data, a search is performed from multiple preset dead time control tables to determine the target dead time control table corresponding to the current operating condition data. The dead time control table includes the dead time corresponding to each switching cycle within a power frequency cycle, and each dead time control table corresponds to different test operating condition data of the photovoltaic module. The operating drive signals for each switch in the DC-side conversion circuit are generated based on the target dead-time control table.

2. The method according to claim 1, characterized in that, The dead-time control table is obtained in the following way: For each of the test conditions, under the condition that the photovoltaic module operates according to the test conditions, the off-time and / or on-time of each switching transistor in the DC-side conversion circuit are obtained for each switching cycle within one power frequency cycle. Based on the turn-off measurement duration and / or turn-on measurement duration of each switch in each switching cycle, a dead time control table corresponding to the test condition data is obtained.

3. The method according to claim 2, characterized in that, The method for obtaining a dead-time control table corresponding to the test condition data based on the turn-off measurement duration corresponding to each switching cycle includes: Obtain the device deviation parameters corresponding to the switching transistor; Based on the device deviation parameters, the turn-off measurement duration corresponding to each switching cycle is compensated to obtain the target turn-off duration corresponding to each switching cycle. Based on the target off-time corresponding to each switching cycle, a dead-time control table corresponding to the test condition data is obtained.

4. The method according to claim 3, characterized in that, One power frequency cycle includes multiple control time periods, each control time period includes multiple switching cycles, and the dead time control table includes the dead time corresponding to each control time period. The method of obtaining the dead-time control table corresponding to the test condition data based on the target turn-off duration corresponding to each switching cycle includes: For each control time period, the dead time corresponding to each control time period in the dead time control table is determined based on the maximum value among the target off-times corresponding to the multiple switching cycles included in the control time period.

5. The method according to claim 1, characterized in that, The step of searching through multiple preset dead-time control tables based on the current operating condition data to determine the target dead-time control table corresponding to the current operating condition data includes: From the different test condition data, determine the test condition data with the smallest difference from the current test condition data; The dead time control table corresponding to the test condition data with the smallest difference is determined as the target dead time control table.

6. The method according to claim 1, characterized in that, The generation of operating drive signals for each switch in the DC-side converter circuit based on the target dead-time control table includes: Obtain the AC output voltage of the power converter; The current phase in the power frequency cycle is determined based on the AC output voltage. The working drive signal is generated based on the current phase and the target dead time control table.

7. A power converter, characterized in that, The DC-side conversion circuit in the power converter is connected to the photovoltaic module, and the power converter includes: A controller for performing the steps of the method according to any one of claims 1 to 6.

8. The power converter according to claim 7, characterized in that, The controller includes a microcontroller and a programmable logic device, wherein, The microcontroller is used to acquire the current operating condition data of the photovoltaic module, and to search and process multiple preset dead time control tables based on the current operating condition data to determine the target dead time control table corresponding to the current operating condition data. The programmable logic device is used to generate the operating drive signals for each switch in the DC-side converter circuit based on the target dead-time control table. Alternatively, the controller may be a programmable logic device.

9. A chip, characterized in that, The chip includes a microcontroller, which is configured in a power converter. The DC-side conversion circuit in the power converter is connected to the photovoltaic module. The power converter also includes a programmable logic device. The microcontroller is used to acquire the current operating condition data of the photovoltaic module; based on the current operating condition data, it searches through multiple preset dead time control tables to determine the target dead time control table corresponding to the current operating condition data, and sends the target dead time control table to the programmable logic device so that the programmable logic device can generate the working drive signals of each switch in the DC-side conversion circuit based on the target dead time control table. Each dead time control table corresponds to different test operating condition data of the photovoltaic module, and the dead time control table includes the dead time corresponding to each switching cycle within one power frequency cycle.

10. A chip, characterized in that, The chip includes a programmable logic device, which is configured to be disposed in a power converter, wherein the DC-side conversion circuit in the power converter is connected to a photovoltaic module, and the programmable logic device is configured to perform the steps of the method according to any one of claims 1 to 6.

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