Control method of LLC resonant converter, processor, converter and medium

Abstract

The invention provides a control method of an LLC resonant converter, a processor, a converter and a medium, and relates to the technical field of power supplies. The LLC resonant converter comprises a first processor and a second processor. The method comprises the following steps: the second processor obtains a PWM hiccup sequence generated by the first processor; according to the PWM hiccup sequence, determining whether a condition of entering a hiccup mode is satisfied; if yes, a corresponding PWM modulation task is determined according to the PWM hiccup sequence, and the PWM modulation task comprises each PWM modulation period and PWM switch information of each PWM modulation period; the PWM modulation period is smaller than or equal to the PWM switching period; and controlling the switching state of PWM in the LLC resonant converter according to the PWM modulation task, and realizing hiccup control corresponding to the LLC control task. According to the method, the output current ripple of the LLC under the low-voltage light-load working condition can be effectively reduced, the ripple amplitude is reduced, and the fluctuation period is shortened.

Description

Technical Field

[0001] The present application relates to the technical field of power supplies, and in particular, to a control method, a processor, a converter, and a medium for an LLC resonant converter. Background Art

[0002] With the development of new energy technologies and power supply power electronics technologies, LLC resonant converters (abbreviation: LLC) are widely used in various high-efficiency energy conversion scenarios, such as power voltage converters, battery charge and discharge systems, server power supply systems, electric vehicle charging piles, solar inverters, etc.

[0003] In related technologies, the mainstream control method of LLC is frequency modulation, and the gain control is achieved by changing the switching frequency of LLC. Limited by the upper limit of the switching frequency of LLC, the gain brought by LLC through frequency modulation cannot be reduced to 0. Therefore, in the low-voltage and light-load working condition, when the switching frequency reaches the upper limit, the gain can be reduced to 0 through Burst (intermittent hiccups). However, the current hiccup frequency of the Burst scheme is bound to the control frequency and is lower than the lower limit of the LLC switching frequency, resulting in a large amplitude and long period of the output current ripple of LLC during hiccup control.

[0004] Therefore, a control scheme for an LLC resonant converter that can reduce the output current ripple of LLC under low-voltage and light-load working conditions is needed. Summary of the Invention

[0005] The embodiments of the present application provide a control method, a processor, a converter, and a medium for an LLC resonant converter, which can effectively reduce the output current ripple of LLC under low-voltage and light-load working conditions, reduce the ripple amplitude, and shorten the fluctuation period.

[0006] In a first aspect, the embodiments of the present application provide a control method for an LLC resonant converter. The LLC resonant converter includes a first processor and a second processor. The method includes:

[0007] The second processor obtains a pulse width modulation PWM hiccup sequence generated by the first processor based on an LLC control task;

[0008] Determine whether the condition for the LLC resonant converter to enter the hiccup mode is satisfied according to the PWM hiccup sequence;

[0009] If the condition for the LLC resonant converter to enter the hiccup mode is satisfied, determine a corresponding PWM modulation task according to the PWM hiccup sequence. The PWM modulation task includes each PWM modulation period and the PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period;

[0010] Control the switching state of the PWM in the LLC resonant converter according to the PWM modulation task, and implement the hiccup control corresponding to the LLC control task.

[0011] In a possible implementation manner, determining whether the condition for the LLC resonant converter to enter the hiccup mode is satisfied according to the PWM hiccup sequence includes:

[0012] Judge whether the PWM hiccup sequence satisfies the following constraint conditions:

[0013] The element index at which the current hiccup sequence is executed is recorded as 0, and the PWM hiccup sequence is not an all-on sequence;

[0014] If the constraint conditions are satisfied, it is determined that the condition for the LLC resonant converter to enter the hiccup mode is satisfied.

[0015] In a possible implementation manner, determining the corresponding PWM modulation task according to the PWM hiccup sequence includes:

[0016] Determine the number M of execution cycles of the PWM hiccup sequence according to the ratio of the switching frequency of the PWM to the fixed control frequency of the LLC control task;

[0017] According to the order of the execution cycle index from small to large, determine the PWM modulation periods corresponding to each execution cycle in turn. Specifically,

[0018] For each execution cycle, according to the order of the element index from small to large, determine the corresponding PWM modulation period, PWM modulation period index, and PWM switching information of each PWM modulation period in turn according to each element in the hiccup sequence. Each element in the hiccup sequence corresponds to a PWM modulation period.

[0019] In a possible implementation manner, the hiccup sequence includes N elements. When the element is 0, it means that the driving PWM is in the off state. When the element is 1, it means that the driving PWM is in the on state;

[0020] The hiccup frequency corresponding to the LLC control task is the switching frequency of the PWM / N.

[0021] In a possible implementation manner, controlling the switching state of the PWM in the LLC resonant converter according to the PWM modulation task includes:

[0022] According to the order of the PWM modulation period index from small to large, control the switching state of the PWM in the LLC resonant converter according to the PWM modulation task in turn. Specifically,

[0023] For each PWM modulation period, a corresponding PWM drive is sent according to the PWM switch information of the PWM modulation period, and the PWM drive is used to control the switch state of the PWM in the LLC resonant converter;

[0024] Among them, the element index at which the current hiccup sequence is executed increases with the wave generation of each PWM modulation period, and after the wave generation of the Nth element corresponding to the last PWM modulation period is completed, the element index at which the current hiccup sequence is executed is reset to 0.

[0025] In a possible implementation manner, it further includes:

[0026] Obtain the wave generation enable flag of the PWM generated by the first processor based on the LLC control task;

[0027] Correspondingly, a corresponding first PWM drive is sent according to the PWM switch information of the PWM modulation period, and a corresponding second PWM drive is sent according to the wave generation enable flag of the PWM;

[0028] Among them, the wave generation enable flag of the PWM includes an enable wave generation flag and a disable wave generation flag. The enable wave generation flag is used to drive the corresponding PWM to be in an open state, and the disable wave generation flag is used to drive the corresponding PWM to be in a closed state. The priority of the second PWM drive is higher than that of the first PWM drive.

[0029] In a possible implementation manner, if the condition for the LLC resonant converter to enter the hiccup mode is not met, it further includes:

[0030] Obtain the PWM frequency and PWM switch enable generated by the first processor based on the LLC control task;

[0031] According to the PWM frequency and the PWM switch enable, complete the variable frequency control corresponding to the LLC control task.

[0032] In a second aspect, an embodiment of the present application provides a processor, including:

[0033] An acquisition module, configured to acquire a pulse width modulation PWM hiccup sequence generated by another processor based on an LLC control task;

[0034] A processing module, configured to determine whether the conditions for the LLC resonant converter to enter the hiccup mode are met according to the PWM hiccup sequence; if the conditions for the LLC resonant converter to enter the hiccup mode are met, determine corresponding PWM modulation tasks according to the PWM hiccup sequence, where the PWM modulation tasks include each PWM modulation period and the PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period; control the on / off state of the PWM in the LLC resonant converter according to the PWM modulation tasks to implement the hiccup control corresponding to the LLC control task.

[0035] In a third aspect, an embodiment of the present application provides an LLC resonant converter, including:

[0036] A first processor, a second processor, and a memory respectively communicatively connected to the first processor and the second processor;

[0037] The memory is used to store computer execution instructions;

[0038] The first processor is configured to process the LLC control task and send the generated pulse width modulation (PWM) hiccup sequence to the second processor;

[0039] The second processor is configured to execute the computer execution instructions stored in the memory, so that the second processor executes the first aspect and / or various possible implementation manners of the first aspect as described above.

[0040] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, in which computer execution instructions are stored, and when the computer execution instructions are executed by a processor, they are used to implement the first aspect and / or various possible implementation manners of the first aspect as described above.

[0041] In a fifth aspect, an embodiment of the present application provides a computer program product, including a computer program, and when the computer program is executed by a processor, it is used to implement the first aspect and / or various possible implementation manners of the first aspect as described above.

[0042] The embodiments of the present application provide a control method, a processor, a converter and a medium for an LLC resonant converter. The first processor of the LLC resonant converter can execute LLC control tasks and generate a PWM hiccup sequence accordingly. After the second processor obtains the PWM hiccup sequence, it can determine whether the conditions for the LLC resonant converter to enter the hiccup mode are met; if so, it can determine the corresponding PWM modulation task according to the PWM hiccup sequence, and execute the PWM modulation task to control the on-off state of the PWM in the LLC resonant converter, so as to realize the hiccup control corresponding to the LLC control task. Through such a setting, after entering the hiccup mode, the second processor can parse the LLC control task into PWM modulation tasks with finer granularity, making the PWM modulation task asynchronous with the LLC control task. The PWM switching frequency is no longer controlled by the timing frequency of the LLC control task, but is changed to be controlled by the PWM modulation frequency. The PWM modulation task can use a PWM modulation period less than or equal to the PWM switching period to realize the on-off control of the PWM for each PWM switching period. The frequency of the PWM modulation is larger and the period is smaller than that of the LLC control task, effectively reducing the output current ripple of the LLC under low-voltage and light-load conditions, reducing the ripple amplitude and shortening the fluctuation period, and improving the performance of the LLC resonant converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] The accompanying drawings herein are incorporated into the specification and form a part of the specification, showing embodiments consistent with the present application, and are used together with the specification to explain the principles of the present application.

[0044] Figure 1 is the gain curve of the LLC resonant converter;

[0045] Figure 2 is a schematic diagram of the working change of the LLC resonant converter in the related art;

[0046] Figure 3 is the system architecture diagram of an embodiment of the present application;

[0047] Figure 4 is the flowchart of the control method of the LLC resonant converter according to an embodiment of the present application;

[0048] Figure 5 is the schematic diagram of the topology structure of the LLC resonant converter;

[0049] Figure 6 is the schematic diagram of the working change of the LLC resonant converter according to an embodiment of the present application;

[0050] Figure 7 is the schematic diagram of the structure of the processor according to an embodiment of the present application;

[0051] Figure 8It is a schematic structural diagram of an LLC resonant converter according to an embodiment of the present application.

[0052] Through the above-mentioned drawings, specific embodiments of the present application have been shown, and there will be more detailed descriptions hereinafter. These drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. Specific Embodiments

[0053] Here, exemplary embodiments will be described in detail, and examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices and methods consistent with some aspects of the present application as detailed in the appended claims.

[0054] In the description and claims of the present application and the above-mentioned drawings, terms such as "first", "second", "third", "fourth", etc. (if any) are used to distinguish similar objects and do not necessarily have to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present application described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device that includes a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0055] In the technical solution of the present application, the collection, storage, use, processing, transmission, provision, disclosure, etc. of information such as financial data or user data comply with the provisions of relevant laws and regulations and do not violate public order and good customs.

[0056] It should be noted that in the embodiments of the present application, some industry-existing solutions such as certain software, components, models, etc. may be mentioned. They should be considered exemplary, and their purpose is only to illustrate the feasibility in the implementation of the technical solution of the present application, but it does not mean that the applicant has already or necessarily used this solution.

[0057] It should also 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 for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties. Moreover, the collection, use, and processing of relevant data need to comply with relevant laws, regulations, and standards, and corresponding operation entrances are provided for users to choose to authorize or reject.

[0058] The control method, processor, converter, and medium of the LLC resonant converter in this application can be used in the power technology field and can also be used in any field other than the power technology field, such as the LLC output control technology field, etc. The application fields of the control method, processor, converter, and medium of the LLC resonant converter in this application are not limited.

[0059] The control method, processor, converter, and medium of the LLC resonant converter in this application can be applied to electronic devices equipped with LLC resonant converters. As long as there is a multi-core processor in the LLC resonant converter of the electronic device, the control method, processor, converter, and medium of the LLC resonant converter in this application can be applied.

[0060] First, the nouns involved in this application are explained:

[0061] An LLC resonant converter is a power electronic converter commonly used in power management systems, especially in high-efficiency power conversion applications. An LLC resonant converter is a soft-switching converter that uses a resonant circuit to achieve efficient energy transfer and reduce switching losses. The core of an LLC resonant converter is the resonant network, which is usually composed of an inductor (L) and a capacitor (C). This network can be in a series or parallel structure, and the common one is the series-parallel (LLC) structure, which is used for boosting or bucking the voltage and providing electrical isolation at the same time. Usually, MOSFETs or IGBTs are used, and the output voltage is regulated by controlling the switching frequency. At the output end, a rectifier and a filter are used to convert alternating current into direct current and smooth the output voltage.

[0062] In an LLC resonant converter, variable frequency control and hiccup mode are two common control strategies used to regulate the output voltage and protect the circuit. Variable frequency control is one of the core control strategies of the LLC resonant converter, which adjusts the output voltage by changing the switching frequency. The resonant frequency of the LLC converter is determined by the resonant inductor and capacitor and is usually designed to operate within a specific frequency range. When the switching frequency is higher than the resonant frequency, the converter behaves inductively, which is typically used to reduce the output voltage; when the switching frequency is lower than the resonant frequency, the converter behaves capacitively, which is typically used to increase the output voltage. The hiccup mode is a protection mechanism commonly used for protection under overload, short circuit, or other abnormal conditions. Its working principle is to periodically turn on and off the converter to limit the power transmission under fault conditions. When an overload or short circuit is detected, the converter will temporarily turn off the output and then attempt to restart after a period of time. If the fault condition still exists, the converter will turn off again. This periodic on and off behavior is similar to "hiccupping". By limiting the average power transmission under fault conditions, the hiccup mode can prevent circuit components from overheating and being damaged. The hiccup mode is usually implemented through a control circuit that monitors the output voltage and current and triggers the protection mechanism when an abnormality is detected.

[0063] Pulse Width Modulation (PWM) is a digital signal technology used to control analog circuits. By adjusting the width of the pulse (i.e., the duty cycle), PWM can effectively control power transmission, regulate voltage and current, and achieve other control functions. PWM is widely used in fields such as motor control, lighting regulation, audio synthesis, and communication. The PWM signal is a square wave signal with a usually fixed period and frequency, while the width of the pulse (the duration of the high level) can vary. By changing the pulse width, the average output voltage or current can be adjusted. The duty cycle is the ratio of the high level time to the entire cycle time. The duty cycle can vary from 0% to 100%.

[0064] In related technologies, the mainstream control method of LLC is variable frequency modulation, which realizes gain control by changing the switching frequency of LLC. Under low-voltage and light-load conditions, the gain needs to be reduced to 0. Figure 1 is the gain curve of the LLC resonant converter, as Figure 1 As can be seen, in the range where the LLC switching frequency is less than 0.5, the gain increases as the LLC switching frequency increases. In the range where the LLC switching frequency is greater than 0.5, the gain decreases as the LLC switching frequency increases, but it can only be reduced to a certain extent. After that, even if the LLC switching frequency is larger, the gain cannot be changed subsequently, that is, the gain cannot be reduced to 0 by changing the switching frequency of LLC. At this time, it is necessary to enter the hiccup mode and use the intermittent hiccup method to reduce the gain to 0.

[0065] The mainstream LLC control method in the current industry is frequency conversion modulation, that is, by adjusting the switching frequency to change the output gain of LLC to achieve the functions of voltage regulation and current regulation. However, limited by the computing power of the single-chip microcomputer and the size of the computing task, it is impossible to perform frequency conversion control calculations following the switching frequency. That is to say, the control frequency of the switch is controlled according to the fixed control frequency of 50 kHz of the control task. It is necessary to calculate the current driving switch frequency of LLC in the control task with a fixed frequency. The control task and the frequency conversion modulation are asynchronous, and generally the fixed frequency of the control task is not higher than the lower limit value of the LLC driving switch frequency.

[0066] Figure 2 It is a schematic diagram of the working changes of the LLC resonant converter in the related technology, as Figure 2 shown. The upper part A in the figure represents the working changes of LLC in the frequency conversion mode, and the lower part B represents the working changes of LLC in the hiccup mode. In the hiccup mode, the hiccup frequency is variable, but since the LLC control task is carried out at a fixed control frequency (usually 50 kHz), the hiccup frequency is limited by the control frequency and is smaller than the control frequency and on the small side no matter how it changes, such as 6.25 kHz, 12.5 kHz, etc. And the PWM switching frequency is usually larger than the control frequency. Taking 200 kHz as an example, usually one control task cycle includes 4 PWM switching cycles, that is, within 4 PWM switching cycles, the PWM switching state is the same, resulting in a large amplitude and long period of the output current ripple fluctuation of LLC during hiccup control.

[0067] When the PWM frequency of LLC reaches the upper limit value, in order to continue to reduce the output gain of LLC, LLC enters the hiccup mode from the frequency conversion mode, as Figure 2 shown. In the hiccup mode, taking N control task cycles as a group, the PWM is on in m control task cycles and off in N - m control task cycles. The size of N is determined by the minimum gain in the frequency conversion mode and the desired control resolution in the hiccup mode. For the convenience of explaining the principle, N is taken as 8 in this application, and m represents the sequence index of the PWM hiccup sequence. LLC calculates a new m value by the current control algorithm. If LLC is not in the hiccup mode currently, it immediately enters the hiccup mode and assigns the new m value to complete the hiccup sequence of N control cycles. If it is in the hiccup mode, it waits for the completion of the hiccup sequence of the previous N control cycles and then assigns the new m value to complete the hiccup sequence of N control cycles. When N is equal to 8, the hiccup frequency is 6.25 kHz. The larger N is, the lower the hiccup frequency and the larger the ripple.

[0068] Figure 2The dashed box in it can represent a hiccup period. The hiccup frequency corresponding to this hiccup period is 6.25 kHz, and this period corresponds to an LLC control task. The PWM hiccup sequence issued by the LLC control task is 11111110. The LLC control task first issues the first "1", and within 4 PWM switching cycles, the PWM is in the on state. The LLC control task issues the second "1", and within the subsequent 4 PWM switching cycles, the PWM is in the on state,... The LLC control task issues "0", and within 4 PWM switching cycles, the PWM is in the off state. Within this hiccup period, the PWM is in the on state for the first 28 switching cycles and in the off state for the subsequent 4 switching cycles. The hiccup frequency is restricted by the frequency of the control task, resulting in a relatively long hiccup period and a large amplitude of the ripple fluctuation of the LLC output current (that is, after seven cycles of the LLC switching frequency - hiccup frequency, the switch will be turned off, resulting in a sudden drop in the LLC current).

[0069] Based on the above technical problems, the inventive concept of this application lies in: how to provide a control scheme for an LLC resonant converter that can reduce the output current ripple of the LLC under low-voltage and light-load conditions.

[0070] The embodiments of this application provide a control method, a processor, a converter, and a medium for an LLC resonant converter. The hiccup control located in the same processor can be split and executed by two processors. The first processor can execute the LLC control task and generate a PWM hiccup sequence accordingly. After the second processor obtains the PWM hiccup sequence, after determining the condition for entering the hiccup mode accordingly, it can determine a PWM modulation task with a smaller granularity according to the PWM hiccup sequence, making the PWM modulation task asynchronous with the LLC control task. The PWM switching frequency is no longer controlled by the timing frequency of the LLC control task but is instead controlled by the PWM modulation frequency. The PWM modulation task can use a PWM modulation period less than or equal to the PWM switching period to control the on and off of the PWM for each PWM switching cycle, effectively reducing the output current ripple of the LLC under low-voltage and light-load conditions, reducing the ripple amplitude and shortening the fluctuation period, and improving the performance of the LLC resonant converter.

[0071] The following uses specific embodiments to elaborate in detail on the technical solutions of this application and how the technical solutions of this application solve the above technical problems. These several specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.

[0072] Figure 3 is the system architecture diagram of an embodiment of this application, as Figure 3As shown, the LLC resonant converter may include a first processor and a second processor. The first processor is configured to process LLC control tasks to generate a PWM hiccup sequence and send the PWM hiccup sequence to the second processor through infoLlc. The second processor may obtain the PWM hiccup sequence generated by the first processor; determine whether the condition for entering the hiccup mode is met according to the PWM hiccup sequence; if so, determine the corresponding PWM modulation task according to the PWM hiccup sequence, where the PWM modulation task includes each PWM modulation period and the PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period; control the on / off state of the PWM in the LLC resonant converter according to the PWM modulation task to implement the hiccup control corresponding to the LLC control task.

[0073] Figure 4 It is a flowchart of a control method for an LLC resonant converter according to an embodiment of the present application. The LLC resonant converter may include a first processor and a second processor. In this embodiment, the control method of the LLC resonant converter is described with the second processor of the LLC resonant converter as the execution subject. As Figure 4 shown, the control method of the LLC resonant converter may include the following steps:

[0074] S401: The second processor obtains the pulse width modulation (PWM) hiccup sequence generated by the first processor based on the LLC control task.

[0075] In this embodiment, the main control chip of the LLC resonant converter may be a multi-core chip. The core processor of the main control chip serves as the first processor to process the LLC control tasks, and the coprocessor of the main control chip (such as the CLA of the TI C2000 series chips and the MCS of the Infineon AURIX™ TriCore™ series chips, etc.) or other core processors serve as the second processor to create a new interrupt task and process the PWM driver program of the LLC, that is, process the PWM modulation task. The MCU core on which the PWM modulation task and the control task rely is inconsistent, and the scheduling tasks can be executed in parallel.

[0076] In this embodiment, the LLC control task frequency may be 50 kHz and the PWM switch frequency may be 50 kHz - 200 kHz for principle interpretation, but the actual application is not limited to these parameters.

[0077] Figure 5 It is a schematic diagram of the topological structure of the LLC resonant converter. In the figure, Q1, Q2, Q3, and Q4 are MOS transistors, and the driving switches PWM_A and PWM_B have a standard 50% duty cycle. PWM_A drives Figure 5 Q1 and Q4 in it, and PWM_B drives Q2 and Q3.

[0078] In this embodiment, when the control task time base count is ZERO, the ADC sampling required for closed-loop control is triggered. The ADC samples the LLC output voltage and output current, and after the sampling is completed, the ADC triggers an interrupt task, that is, the LLC control task.

[0079] Exemplarily, Table 1 below is a correspondence table between the PWM hiccup sequence and the sequence index:

[0080] Table 1

[0081]

[0082] As shown in Table 1, m represents the sequence index of the PWM hiccup sequence. The element 0 in the sequence represents the PWM drive is off, and the element 1 represents the PWM drive is on. When m = 0, it means the PWM is in the fully off state, and when m = 8, it means the PWM is in the fully on state.

[0083] The first processor calculates the current LLC PWM frequency frequency1 based on the sampling information. The range of frequency1 is 50 kHz - Q mHz, (Q mHz is the main frequency of the main control chip).

[0084] If frequency1 is less than or equal to 200 kHz, then m is equal to 8. If frequency1 is greater than 200 kHz, then the part of frequency1 exceeding the upper limit (the part greater than 200 kHz) is converted into m (one of 0 - 7), and frequency1 is limited to the LLC frequency upper limit value of 200 kHz. After the first processor calculates the sequence index m, the corresponding PWM hiccup sequence can be determined according to Table 1.

[0085] In this embodiment, after the first processor calculates the PWM hiccup sequence based on the LLC control task, the PWM hiccup sequence and the PWM frequency frequency1 can be transmitted to the second processor through a single integer data infoLlc.

[0086] In this embodiment, if the first processor also calculates or receives the PWM wave generation enable flag based on the LLC control task, the PWM wave generation enable flag can also be transmitted to the second processor through infoLlc.

[0087] In this embodiment, since the execution of the LLC control task and the PWM modulation task is asynchronous, in order to ensure the consistency of the control data received by the PWM modulation task from the LLC control task, the information interaction between the LLC control task and the PWM modulation task is only transmitted through a single integer data infoLlc.

[0088] S402: Determine whether the conditions for the LLC resonant converter to enter the hiccup mode are met according to the PWM hiccup sequence.

[0089] In this embodiment, if the PWM hiccup sequence meets the conditions for the LLC resonant converter to enter the hiccup mode, it enters the hiccup mode; if it does not meet the conditions for the LLC resonant converter to enter the hiccup mode, it enters the variable frequency mode.

[0090] S403: If the conditions for the LLC resonant converter to enter the hiccup mode are met, determine the corresponding PWM modulation task according to the PWM hiccup sequence.

[0091] In this embodiment, the PWM modulation task may include each PWM modulation period and the PWM switch information of each PWM modulation period.

[0092] In this embodiment, the PWM modulation period is less than or equal to the PWM switch period.

[0093] In this embodiment, the PWM modulation task can split the LLC control task into finer-grained PWM modulation periods, so that the scheduling frequency of the PWM modulation task follows the PWM switch frequency (which can be achieved by using the PWM time base trigger), and realizes the control of PWM on and off for each PWM switch period. From N LLC control periods to N minimum PWM switch periods of LLC, the frequency of the hiccup sequence is effectively increased, thereby reducing the output current ripple during a single LLC hiccup.

[0094] In this embodiment, during the PWM modulation period, the PWM drive can be controlled to turn on / off once.

[0095] It should be noted that the execution duration of the PWM modulation task (i.e., one PWM modulation period) cannot be greater than the minimum PWM switch period, otherwise there will be a control risk of task overflow resulting in untimely control or invalidation of the synchronization strategy. If the execution duration of the PWM modulation task is greater than the minimum PWM switch period, it can be considered to trigger the PWM modulation task once every two minimum PWM switch periods, which will correspondingly increase the granularity of the hiccup sequence elements.

[0096] S404: Control the switch state of the PWM in the LLC resonant converter according to the PWM modulation task to achieve the hiccup control corresponding to the LLC control task.

[0097] S405: If the conditions for the LLC resonant converter to enter the hiccup mode are not met, the LLC resonant converter enters the variable frequency mode.

[0098] In this embodiment, the PWM modulation task can split the LLC control task into various PWM modulation cycles. For each PWM modulation cycle, the corresponding PWM switch state can be driven according to the PWM switch information corresponding to the PWM modulation cycle, thereby completing the hiccup control corresponding to this LLC control task.

[0099] In this embodiment, after controlling the switching state of PWM in the LLC resonant converter according to the PWM modulation task, the LLC PWM reload function can be turned off, the PWM shadow register is updated, and the LLC PWM reload function is turned on to complete the hiccup control corresponding to the LLC control task.

[0100] In this embodiment, LLC control and PWM modulation can be separated, creating a scheme that uses the coprocessor of the main control chip to follow the PWM switching frequency to control the on-off state of the PWM drive in LLC cycle by cycle, effectively reducing the output current ripple of LLC under low-voltage and light-load conditions, and the controlled output current ripple has a small amplitude and a short cycle. At the same time, the current ripple of the LLC transformer resonant cavity can be reduced, reducing heat generation, thereby reducing the requirements for the filter. In addition, the PWM modulation program is moved from the main core LLC interrupt control program to the coprocessor PWM program execution, reducing the main core load rate.

[0101] In this embodiment, the first processor of the LLC resonant converter can execute the LLC control task and generate a PWM hiccup sequence accordingly. After the second processor obtains the PWM hiccup sequence, it can determine whether the condition for the LLC resonant converter to enter the hiccup mode is met; if it is met, the corresponding PWM modulation task can be determined according to the PWM hiccup sequence, and the PWM modulation task can be executed to control the switching state of the PWM in the LLC resonant converter to achieve the hiccup control corresponding to the LLC control task. Through such a setting, after entering the hiccup mode, the second processor can be used to parse the LLC control task into a PWM modulation task with a smaller granularity, so that the PWM modulation task is asynchronous with the LLC control task, and the PWM switching frequency is no longer controlled by the LLC control task timing frequency, but is controlled by the PWM modulation frequency. The PWM modulation task can use a PWM modulation period that is less than or equal to the PWM switching period to achieve the control of PWM on and off by PWM switching period. The frequency of PWM modulation is larger than the frequency of the LLC control task, and the period is smaller, which effectively reduces the output current ripple of LLC under low-voltage and light-load conditions, reduces the ripple amplitude and shortens the fluctuation period, and improves the performance of the LLC resonant converter.

[0102] In a possible implementation, the above step S402 determines whether the condition for the LLC resonant converter to enter the hiccup mode is met according to the PWM hiccup sequence, and may include:

[0103] S11: Determine whether the PWM hiccup sequence satisfies the following constraint conditions:

[0104] The index of the element where the current hiccup sequence is executed is recorded as 0, and the PWM hiccup sequence is not a fully open sequence.

[0105] S12: If the constraint conditions are satisfied, determine that the conditions for the LLC resonant converter to enter the hiccup mode are met.

[0106] In this embodiment, recording the index of the element where the current hiccup sequence is executed as 0 can indicate that all elements of the current hiccup sequence have not been executed, which is a brand-new hiccup sequence.

[0107] In this embodiment, if the PWM hiccup sequence is a fully open sequence, it means that the LLC resonant converter is about to enter the variable frequency mode. Taking Table 1 above as an example, when the sequence index m of the PWM hiccup sequence is 8, the PWM is in the fully open state, and the PWM hiccup sequence is a fully open sequence. When m < 8, the PWM is not in the fully open state, the PWM hiccup sequence is not a fully open sequence, and the LLC enters the hiccup mode.

[0108] In this embodiment, according to the index of the element where the current hiccup sequence is executed and the sequence index of the PWM hiccup sequence, it is possible to simply and accurately determine whether the conditions for the LLC resonant converter to enter the hiccup mode are met.

[0109] In a possible embodiment, determining the corresponding PWM modulation task according to the PWM hiccup sequence in step S403 above may include:

[0110] S21: Determine the number M of execution cycles of the PWM hiccup sequence according to the ratio of the switching frequency of the PWM to the fixed control frequency of the LLC control task.

[0111] S22: Determine the PWM modulation periods corresponding to each execution cycle in ascending order of the execution cycle index. Specifically,

[0112] For each execution cycle, determine the corresponding PWM modulation period, PWM modulation period index, and PWM switching information of each PWM modulation period according to the elements in the hiccup sequence in ascending order of the element index. Each element in the hiccup sequence corresponds to a PWM modulation period.

[0113] Exemplarily, if the switching frequency of the PWM is 200 kHz and the fixed control frequency of the LLC control task is 50 kHz, the number M of execution cycles of the PWM hiccup sequence is 4, that is, one control task corresponds to 4 executions of the PWM hiccup sequence.

[0114] The PWM hiccup sequence includes 8 elements, and each of these elements corresponds to a PWM modulation period. That is, in each execution cycle, the corresponding PWM modulation periods can be determined in sequence according to the element indices from 0 to 7. In other words, one LLC control task corresponds to 4 executions of the PWM hiccup sequence, and a total of 32 PWM switch controls occur. One PWM hiccup sequence is executed in one execution cycle, that is, the hiccup frequency is fixed at 25 kHz.

[0115] In this embodiment, when determining the PWM modulation task, the number of execution cycles of the PWM hiccup sequence can be determined first according to the ratio of the switching frequency of the PWM to the fixed control frequency of the LLC control task. In each execution cycle, each element in the hiccup sequence corresponds to a PWM modulation period. According to the order of the element indices from small to large, the PWM modulation period, the PWM modulation period index, and the PWM switch information of each PWM modulation period can be accurately determined.

[0116] In a possible embodiment, the above-mentioned hiccup sequence may include N elements. When the element is 0, it indicates that the driving PWM is in the off state. When the element is 1, it indicates that the driving PWM is in the on state.

[0117] The hiccup frequency corresponding to the above-mentioned LLC control task can be the switching frequency of the PWM / N.

[0118] In this embodiment, N can be 8 or other values, and those skilled in the art can flexibly set it according to actual needs. When N is 8, the hiccup frequency is fixed at 25 kHz.

[0119] In this embodiment, the hiccup frequency corresponding to the LLC control task can be the switching frequency of the PWM / the number of elements in the hiccup sequence, so that each element in the hiccup sequence corresponds to a PWM modulation period, and the on / off of the PWM can be controlled for each PWM switch period.

[0120] In a possible embodiment, controlling the switching state of the PWM in the LLC resonant converter according to the PWM modulation task in step S404 above may include:

[0121] According to the order of the PWM modulation period index from small to large, the switching state of the PWM in the LLC resonant converter is controlled according to the PWM modulation task in sequence. Specifically,

[0122] For each PWM modulation period, the corresponding PWM drive is issued according to the PWM switch information of the PWM modulation period, and the PWM drive is used to control the switching state of the PWM in the LLC resonant converter.

[0123] Among them, the index of the element where the current hiccup sequence is executed increases with the wave generation in each PWM modulation period, and after the wave generation of the Nth element corresponding to the last PWM modulation period is completed, the index of the element where the current hiccup sequence is executed is reset to 0.

[0124] In this embodiment, wave generation can be to send the PWM switch information of each PWM modulation period to the corresponding PWM driver.

[0125] Exemplarily, Figure 6 is a schematic diagram of the working change of the LLC resonant converter according to an embodiment of the present application, as Figure 6 shown. The upper part A in the figure represents the working change when the LLC is in the variable frequency mode, and the lower part B represents the working change when the LLC is in the hiccup mode. Figure 6 The dashed box in the figure represents a hiccup cycle. In the hiccup mode, the hiccup frequency is fixed at 25 kHz, which is greater than Figure 2 the 6.25 kHz shown.

[0126] If the PWM hiccup sequence issued by the LLC control task is "11111110", then the PWM modulation task needs to execute "11111110" 4 times. In each execution cycle, the PWM modulation task first issues the first "1", the PWM executes one switching cycle, the PWM modulation task issues the second "1", the PWM executes one switching cycle,..., the PWM modulation task issues "0", the PWM executes one switching cycle, and this execution cycle is completed.

[0127] The PWM modulation task first issues 7 times of PWM drive to turn on, then issues 1 time of PWM drive to turn off, then issues 7 times of PWM drive to turn on again, and then issues 1 time of PWM drive to turn off again, repeating 4 times until this LLC control task is completed. During this process, the PWM executes the PWM hiccup sequence 4 times, while Figure 2 the hiccup mode shown only executes one hiccup sequence. The modulation program has a higher frequency and a smaller period compared to the original control task, and can more effectively control PWM_A and PWM_B. Compared with Figure 2 , Figure 6 the LLC output current curve below is smoother and has smaller ripple.

[0128] Figure 2 In the related technology shown, the switching control frequency of the PWM is limited by the frequency of the control task timing, that is, 50 Hz, and the PWM switch is controlled within 1 / 50 kHz. Figure 6 In the figure, the switching control frequency of the PWM is controlled by the frequency of the PWM modulation program, and the minimum can reach 1 / 200 kHz, thereby avoiding a large drop in the current ripple in a long period.

[0129] Exemplarily, when the element index of the current hiccup sequence being executed reaches the first sequence element in the first execution cycle, it can be 10. The first "1" represents the execution cycle index, and the second "1" represents the element index. When it reaches the second sequence element, it can be 11, and when it reaches the eighth sequence element, it can be 17. When it reaches the first sequence element in the fourth execution cycle, it can be 40, and when it reaches the eighth sequence element, it can be 47. At this time, all 4 PWM hiccup sequences have been executed, and the element index of the current hiccup sequence being executed can be reset to 0.

[0130] In this embodiment, after determining the PWM modulation period, the PWM modulation period index, and the PWM switch information of each PWM modulation period, according to the ascending order of the PWM modulation period index, the on / off control of the PWM can be achieved, and the hiccup control corresponding to the current LLC control task can be completed. In addition, after generating the waveform for the Nth element corresponding to the last PWM modulation period, the element index of the current hiccup sequence being executed can be reset to 0 to enter the PWM modulation of the next LLC control task.

[0131] In a possible embodiment, the method may further include:

[0132] Obtain the waveform generation enable flag of the PWM generated by the first processor based on the LLC control task.

[0133] Correspondingly, the corresponding first PWM drive can be issued according to the PWM switch information of the PWM modulation period, and the corresponding second PWM drive can be issued according to the waveform generation enable flag of the PWM.

[0134] Wherein, the waveform generation enable flag of the PWM includes an enable waveform generation flag and a disable waveform generation flag. The enable waveform generation flag is used to drive the corresponding PWM to be in the on state, and the disable waveform generation flag is used to drive the corresponding PWM to be in the off state. The priority of the second PWM drive is higher than that of the first PWM drive.

[0135] In this embodiment, the waveform generation enable flag (enable waveform generation / disable waveform generation) of the PWM is a high-priority instruction. Suppose that currently, in the hiccup mode, for the 3rd / 8th PWM drive issued in a certain sequence, this PWM drive is in the on state. At the same time, in the 50kHz control task algorithm, a fault is detected. For hardware protection considerations, at this time, this waveform generation enable flag needs to be sent to the PWM task together with the hiccup sequence to change the on / off state of the final PWM drive.

[0136] In this embodiment, when the first processor processes the LLC control task, it may also generate a PWM wave generation enable flag. The first processor will send the PWM wave generation enable flag and the PWM hiccup sequence to the second processor together to complete the PWM drive, and the priority of the PWM wave generation enable flag is higher.

[0137] In a possible embodiment, if the conditions for the LLC resonant converter to enter the hiccup mode are not met, the method may further include:

[0138] S31: Obtain the PWM frequency and PWM switch enable generated by the first processor based on the LLC control task.

[0139] S32: Complete the variable frequency control corresponding to the LLC control task according to the PWM frequency and the PWM switch enable.

[0140] In this embodiment, the PWM frequency is frequency1 calculated by the first processor based on the LLC control task; the PWM switch enable may be calculated or obtained by the first processor based on the LLC control task, and it can be determined whether the PWM switch is in the enabled / disabled state.

[0141] In this embodiment, if the conditions for the LLC resonant converter to enter the hiccup mode are not met, the LLC enters the variable frequency mode and performs variable frequency control according to the PWM frequency and the PWM switch enable sent by the first processor.

[0142] The following uses a specific embodiment to elaborate on the control method of the LLC resonant converter of the present application.

[0143] In a specific embodiment, the LLC resonant converter in a certain power supply module is performing power conversion. The main control chip of the LLC resonant converter includes a core processor and a coprocessor. The fixed control frequency of the control task is 50 kHz, and the switching frequency of the PWM is 200 kHz. At a certain moment, the load of the power supply module drops off, and the LLC resonant converter is in a low-voltage and light-load working condition. The specific control process of the LLC resonant converter is as follows:

[0144] First step, when the control task time base count of the core processor is ZERO, it triggers the ADC sampling required for closed-loop control. The ADC samples the LLC output voltage and output current, and after the sampling is completed, the ADC triggers an interrupt task, calculates the current LLC PWM frequency frequency1 according to the sampling information, and generates a PWM wave generation enable flag.

[0145] Second step, the core processor determines that frequency1 is greater than 200 kHz, and converts the part greater than 200 kHz into a sequence index m = 7.

[0146] In the third step, the core processor sends m = 7 and the PWM wave generation enable flag to the coprocessor through a single integer data infoLlc.

[0147] In the fourth step, the coprocessor determines that the element index of the current hiccup sequence is recorded as 0, and the sequence index m < 8, and the hiccup sequence corresponding to m is not a fully open sequence, so it is determined that the condition for the LLC resonant converter to enter the hiccup mode is met.

[0148] In the fifth step, the coprocessor determines that the PWM hiccup sequence corresponding to m = 7 is "11111110", and determines that the execution period of this PWM hiccup sequence is 4 times.

[0149] In the sixth step, in each execution cycle, the coprocessor determines the corresponding PWM modulation period, PWM modulation period index, and PWM switch information of each PWM modulation period in turn according to the elements in the hiccup sequence in ascending order of the element index. Each element in the hiccup sequence corresponds to a PWM modulation period.

[0150] In the seventh step, the coprocessor issues the corresponding PWM drive in turn according to the PWM switch information of the PWM modulation period in ascending order of the PWM modulation period index, that is, issues 7 PWM drives to turn on first, then issues 1 PWM drive to turn off, then issues 7 PWM drives to turn on again, and then issues 1 PWM drive to turn off, repeating 4 times until the hiccup control corresponding to the current LLC control task is completed.

[0151] In the eighth step, after the coprocessor completes the wave generation of the 8th element "0" corresponding to the last PWM modulation period, it resets the element index of the current hiccup sequence to 0.

[0152] In the ninth step, the coprocessor turns off the LLC PWM reload function; updates the PWM shadow register; turns on the LLC PWM reload function; when the LLC PWM time base counts to ZERO, loads and validates the value in the PWM shadow register, updates the PWM wave generation enable flag, the counting period of the PWM time base, and the comparison points corresponding to the period to the latest, and repeats the above first step - ninth step.

[0153] Figure 7 is a schematic structural diagram of a processor according to an embodiment of the present application, as Figure 7As shown in the figure, the processor includes: an acquisition module 71, configured to acquire a pulse width modulation (PWM) hiccup sequence generated by another processor based on an LLC control task; a processing module 72, configured to determine whether the condition for the LLC resonant converter to enter the hiccup mode is satisfied according to the PWM hiccup sequence; if the condition for the LLC resonant converter to enter the hiccup mode is satisfied, determine a corresponding PWM modulation task according to the PWM hiccup sequence, where the PWM modulation task includes each PWM modulation period and the PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period; control the on / off state of the PWM in the LLC resonant converter according to the PWM modulation task to implement the hiccup control corresponding to the LLC control task.

[0154] The processor provided in the embodiment of the present application can execute the technical solutions shown in the above method embodiments, and its implementation principle and beneficial effects are similar, and will not be elaborated here.

[0155] Figure 8 FIG. is a schematic structural diagram of an LLC resonant converter according to an embodiment of the present application, as Figure 8 shown, the LLC resonant converter includes: a first processor 801, a second processor 802, and a memory 803 respectively communicatively connected to the first processor 801 and the second processor 802; the memory 803 stores computer-executable instructions; the first processor 801 processes the LLC control task and sends the generated pulse width modulation (PWM) hiccup sequence to the second processor 802; the second processor 802 executes the computer-executable instructions stored in the memory 803 to implement the steps of the control method of the LLC resonant converter in the above method embodiments.

[0156] In the above LLC resonant converter, the memory 803 is directly or indirectly electrically connected to the first processor 801 / second processor 802 to realize data transmission or interaction. For example, these components can be electrically connected to each other through one or more communication buses or signal lines, such as being connected through a bus. The memory 803 stores computer-executable instructions for implementing a data access control method, including at least one software function module that can be stored in the memory 803 in the form of software or firmware. The first processor 801 / second processor 802 executes various functional applications and data processing by running the software programs and modules stored in the memory 803.

[0157] Both the first processor 801 and the second processor 802 should have the permission to access the memory 803. At least the first processor 801 should have read / write permission for the memory 803, and the second processor 802 should have read permission.

[0158] The memory 803 can be, but is not limited to, Random Access Memory (RAM), Read Only Memory (ROM), Programmable Read-Only Memory (PROM), Erasable Programmable Read-Only Memory (EPROM), Electric Erasable Programmable Read-Only Memory (EEPROM), etc. Among them, the memory 803 is used to store programs. After receiving the execution instructions, the first processor 801 / second processor 802 executes the programs. Further, the software programs and modules in the memory 803 may further include an operating system, which may include various software components and / or drivers for managing system tasks (such as memory management, storage device control, power management, etc.), and may communicate with various hardware or software components to provide a running environment for other software components.

[0159] The first processor 801 / second processor 802 can be an integrated circuit chip with signal processing capabilities. The above-mentioned first processor 801 / second processor 802 can be a general-purpose processor, including a Central Processing Unit (CPU), a Network Processor (NP), etc. It can implement or execute the various methods, steps, and logic block diagrams disclosed in the embodiments of the present application. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0160] An embodiment of the present application further provides a computer-readable storage medium, in which computer-executable instructions are stored. When the computer-executable instructions are executed by a processor, they are used to implement the steps of the method embodiments of the present application.

[0161] An embodiment of the present application further provides a computer program product, including a computer program. When the computer program is executed by a processor, it implements the steps of the method embodiments of the present application.

[0162] It should be noted that, for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that this application is not limited by the described action sequence, because according to this application, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to this application.

[0163] It should be further noted that although the steps in the flowchart are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear description in this article, the execution of these steps has no strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowchart may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps.

[0164] It should be understood that the above device embodiments are merely illustrative, and the devices of this application can also be implemented in other ways. For example, the division of units / modules in the above embodiments is only a logical function division, and there can be other division methods in actual implementation. For example, multiple units, modules or components can be combined, or can be integrated into another system, or some features can be ignored or not executed.

[0165] In addition, unless otherwise specified, in each embodiment of this application, each functional unit / module can be integrated in one unit / module, or each unit / module can exist physically alone, or two or more units / modules can be integrated together. The above integrated unit / module can be implemented in the form of hardware or in the form of a software program module.

[0166] In the above embodiments, the descriptions of each embodiment have their own emphases. For the parts not detailed in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combinations of these technical features do not conflict, they should all be considered as the scope described in this specification.

[0167] Other embodiments of the present application will be readily apparent to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. The present application is intended to cover any variations, uses, or adaptations of the present application, which follow the general principles of the present application and include known common general knowledge or conventional technical means in the technical field not disclosed in the present application. The specification and examples are only to be considered as exemplary, and the true scope and spirit of the present application are pointed out by the appended claims.

[0168] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and various modifications and changes can be made without departing from its scope. The scope of the present application is only limited by the appended claims.

Claims

1. A control method for an LLC resonant converter, characterized in that: The LLC resonant converter includes a first processor and a second processor, and the method includes: The second processor obtains a pulse width modulation (PWM) hiccup sequence generated by the first processor based on an LLC control task; Determining whether a condition for the LLC resonant converter to enter a hiccup mode is met according to the PWM hiccup sequence; If the condition that the LLC resonant converter enters the hiccup mode is met, a corresponding PWM modulation task is determined according to the PWM hiccup sequence, wherein the PWM modulation task includes each PWM modulation period and PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period; The switching state of the PWM in the LLC resonant converter is controlled according to the PWM modulation task to implement the hiccup control corresponding to the LLC control task.

2. The control method of the LLC resonant converter according to claim 1, characterized in that: The determining, according to the PWM hiccup sequence, whether a condition for the LLC resonant converter to enter the hiccup mode is met includes: Determine whether the PWM hiccup sequence satisfies the following constraints: The element index record of the current hiccup sequence execution is 0, and the PWM hiccup sequence is not a full-on sequence; If the constraint condition is met, it is determined that a condition for the LLC resonant converter to enter the hiccup mode is met.

3. The control method of the LLC resonant converter according to claim 1, characterized in that: The determining the corresponding PWM modulation task according to the PWM hiccup sequence includes: Determining the number M of execution cycles of the PWM hiccup sequence according to a ratio of the PWM switching frequency to the fixed control frequency of the LLC control task; According to the order of execution cycle index from small to large, the PWM modulation period corresponding to each execution cycle is determined in turn. Specifically, For each execution cycle, the corresponding PWM modulation period, PWM modulation period index and PWM switch information of each PWM modulation period are determined according to each element in the hiccup sequence in order of element index from small to large, and each element in the hiccup sequence corresponds to a PWM modulation period.

4. The control method of the LLC resonant converter according to claim 3, characterized in that: The hiccup sequence includes N elements, when the element is 0, it indicates that the driving PWM is in the off state, and when the element is 1, it indicates that the driving PWM is in the on state; The hiccup frequency corresponding to the LLC control task is the switching frequency of the PWM / N.

5. The control method of the LLC resonant converter according to claim 4, characterized in that: The controlling the switching state of the PWM in the LLC resonant converter according to the PWM modulation task includes: According to the order of the PWM modulation cycle index from small to large, the switching state of the PWM in the LLC resonant converter is controlled according to the PWM modulation task in turn. Specifically, For each PWM modulation cycle, a corresponding PWM drive is issued according to the PWM switch information of the PWM modulation cycle, wherein the PWM drive is used to control the switch state of the PWM in the LLC resonant converter; The element index executed by the current hiccup sequence is automatically increased with the wave transmission of each PWM modulation cycle, and after the wave transmission of the Nth element corresponding to the last PWM modulation cycle is completed, the element index executed by the current hiccup sequence is reset to 0.

6. The control method of the LLC resonant converter according to claim 5, characterized in that: Also includes: Obtaining a PWM wave enabling flag generated by the first processor based on the LLC control task; Correspondingly, a corresponding first PWM drive is issued according to the PWM switch information of the PWM modulation period, and a corresponding second PWM drive is issued according to the PWM wave enabling flag; Among them, the PWM wave transmission enable flag includes an enable wave transmission flag and a disable wave transmission flag, the enable wave transmission flag is used to drive the corresponding PWM to be in an open state, and the disable wave transmission flag is used to drive the corresponding PWM to be in a closed state, and the priority of the second PWM drive is higher than the first PWM drive.

7. The control method of the LLC resonant converter according to any one of claims 1 to 6, characterized in that: If the conditions for the LLC resonant converter to enter hiccup mode are not met, they also include: Obtaining a PWM frequency and a PWM switch enable generated by the first processor based on an LLC control task; According to the PWM frequency and the PWM switch enable, the frequency conversion control corresponding to the LLC control task is completed.

8. A processor, characterized in that: include: An acquisition module, used for acquiring a pulse width modulation (PWM) hiccup sequence generated by another processor based on an LLC control task; A processing module is used to determine whether a condition for an LLC resonant converter to enter a hiccup mode is met according to the PWM hiccup sequence; if the condition for the LLC resonant converter to enter the hiccup mode is met, determine a corresponding PWM modulation task according to the PWM hiccup sequence, wherein the PWM modulation task includes each PWM modulation period and PWM switch information of each PWM modulation period; the PWM modulation period is less than or equal to the PWM switch period; and control a PWM switch state in the LLC resonant converter according to the PWM modulation task to implement hiccup control corresponding to the LLC control task.

9. An LLC resonant converter, characterized in that: include: A first processor, a second processor, and memories communicatively connected to the first processor and the second processor respectively; The memory is used to store computer-executable instructions; The first processor is used for processing LLC control tasks and sending the generated pulse width modulation (PWM) hiccup sequence to the second processor; The second processor is used to execute the computer-executable instructions stored in the memory, so that the second processor executes the control method of the LLC resonant converter according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer-executable instructions, and when the computer-executable instructions are executed by a processor, they are used to implement the control method of the LLC resonant converter according to any one of claims 1 to 7.

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