FSBB converter control method and device, electronic equipment and storage medium

Abstract

The invention provides an FSBB converter control method and device, electronic equipment and a storage medium, and relates to the technical field of electronic control. The method comprises the following steps: acquiring the output voltage of the FSBB converter; determining a reference conduction duration according to the output voltage and a target output voltage of the FSBB converter; determining a target conduction duration of a switch tube in the FSBB converter in a single work period according to the reference conduction duration; and controlling the switch-on and switch-off of the switch tube in the FSBB converter according to the target switch-on duration of the switch tube. Therefore, the FSBB converter directly determines the target conduction duration of the switching tube in a single working period by using the reference conduction duration, and the control logic is simplified. Compared with the traditional scheme of respectively controlling the switching tubes by judging mode switching logic, the FSBB converter does not depend on mode judgment any more, but realizes automatic switching of the three modes through dynamic adjustment of unified control variables, so that the complexity of a control algorithm is reduced, and the real-time performance and the efficiency of the FSBB converter are improved.

Description

Technical Field

[0001] The present invention relates to the field of electronic control technology, and in particular to a FSBB converter control method, device, electronic equipment and storage medium. Background Art

[0002] The Four Switch Buck Boost (FSBB) converter can achieve bidirectional boost and buck due to its same output polarity. It has a wide range of boost and buck and is widely used in photovoltaic energy storage, battery charging and discharging and other usage scenarios. At present, the control strategy of FSBB is to determine the current working mode according to the input voltage and output voltage, such as Boost mode (boost mode) or Buck mode (buck mode) or Boost-Buck mode (boost and buck mode). That is, the judgment logic and processing need to be performed every time the mode is switched, which makes the control strategy logically complex. This complex control logic increases the response time of the FSBB converter and affects the dynamic performance of the FSBB converter. Summary of the invention

[0003] The purpose of the embodiments of the present application is to provide a FSBB converter control method, device, electronic device and storage medium, aiming to reduce the complexity of the control algorithm and improve the real-time performance and efficiency of the FSBB converter.

[0004] In a first aspect, an embodiment of the present application provides a FSBB converter control method, the method comprising:

[0005] Obtaining an output voltage of the FSBB converter;

[0006] determining a reference on-time according to the output voltage and a target output voltage of the FSBB converter;

[0007] Determine a target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time;

[0008] The switch tube in the FSBB converter is controlled to be turned on and off according to the target on time of the switch tube.

[0009] In some embodiments, the target on-time includes the on-time of the buck working tube in the FSBB converter and the on-time of the buck freewheeling tube in the FSBB converter, and determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time includes:

[0010] When the reference on-time is less than or equal to the first on-time, the reference on-time is used as the on-time of the buck working tube, wherein the first on-time is the maximum on-time of the buck working tube in a single working cycle when the FSBB converter performs buck operation;

[0011] The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

[0012] In some embodiments, the target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter, and the step of determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes:

[0013] When the reference on-time is less than or equal to the first on-time, a second on-time is determined as the on-time of the boost working tube, wherein the second on-time is the minimum on-time of the boost working tube in a single working cycle when the FSBB converter performs boost operation;

[0014] The conduction time length of the boost freewheeling tube is determined according to the conduction time length of the boost working tube.

[0015] In some embodiments, the target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter, and the step of determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes:

[0016] In the case where the reference on-time is greater than the first on-time, the sum of the first difference and the second on-time is used as the on-time of the boost working tube, wherein the first difference is the difference between the reference on-time and the first on-time, and the second on-time is the minimum on-time of the boost working tube in a single working cycle during boosting;

[0017] The conduction time length of the boost freewheeling tube is determined according to the conduction time length of the boost working tube.

[0018] In some implementations, determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time further includes:

[0019] When the reference on-time is greater than the first on-time, the first on-time is used as the on-time of the step-down working tube;

[0020] The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

[0021] In some embodiments, the method further comprises:

[0022] When the reference conduction time is less than or equal to the first conduction time, controlling the operating frequencies of the step-down working tube and the step-down freewheeling tube to be a first frequency, and controlling the operating frequencies of the boost working tube and the boost freewheeling tube to be a second frequency;

[0023] When the reference conduction time is greater than the first conduction time, controlling the operating frequencies of the step-down working tube and the step-down freewheeling tube to be a third frequency, and controlling the operating frequencies of the boost working tube and the boost freewheeling tube to be a fourth frequency;

[0024] The first frequency is greater than the second frequency, the first frequency is greater than the third frequency, the fourth frequency is greater than the third frequency, and the fourth frequency is greater than the second frequency.

[0025] In some embodiments, the method further comprises:

[0026] When the reference on-time is less than or equal to the first on-time, the second on-time is used as the on-time of the boost working tube, and the target on-time of the boost freewheeling tube is determined according to the on-time of the boost working tube;

[0027] In the case where the reference on-time is greater than the first on-time, the difference between the first on-time and the preset adjustment time is used as the on-time of the buck working tube, so that the first output power of the FSBB converter is greater than the second output power, wherein the first output power is the output power before the operating frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase, and the second output power is the output power after the operating frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase;

[0028] The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

[0029] In a second aspect, an embodiment of the present application provides a device, the device comprising:

[0030] An acquisition module, used for acquiring the output voltage of the FSBB converter;

[0031] A first determination module, configured to determine a reference on-time according to the output voltage and a target output voltage of the FSBB converter;

[0032] A second determination module is used to determine a target on-time of the switch tube in the FSBB converter within a single working cycle according to the reference on-time;

[0033] A control module is used to control the switching tube in the FSBB converter to be turned on and off according to the target on-time of the switching tube.

[0034] In a third aspect, an embodiment of the present application provides an electronic device, including:

[0035] a memory configured to store instructions; and

[0036] The processor is configured to call the instruction from the memory and implement the FSBB converter control method provided in the first aspect of the embodiment of the present application when executing the instruction.

[0037] In a fourth aspect, an embodiment of the present application provides a machine-readable storage medium, on which instructions are stored. When the instructions are executed by a processor, the processor implements the FSBB converter control method described in the first aspect of the embodiment of the present application.

[0038] In an embodiment of the present application, the FSBB converter calculates the reference on-time directly based on the deviation between the output voltage and the target output voltage, and uses this as the core control variable, without the need for complex judgment logic and mode selection when switching modes. The FSBB converter uses the reference on-time to directly determine the target on-time of the switch tube within a single working cycle, simplifying the control logic. Compared with the traditional solution of controlling the switch tube separately by judging the mode switching logic (such as Buck, Boost or Buck-Boost mode), the FSBB converter no longer relies on mode judgment, but realizes automatic switching of the three modes through dynamic adjustment of unified control variables. In this way, the response speed of the FSBB converter in the face of input voltage or load changes is significantly improved, and the output voltage is adjusted more quickly and smoothly, while reducing the complexity of the control algorithm and improving the real-time performance and efficiency of the FSBB converter. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is the structural diagram of FSBB converter;

[0040] Figure 2 is a flow chart of a FSBB converter control method provided in an embodiment of the present application;

[0041] Figure 3is a flow logic diagram of the FSBB converter control method provided in an embodiment of the present application;

[0042] Figure 4 is a schematic diagram of output power variation before and after frequency switching provided in an embodiment of the present application;

[0043] Figure 5 is a structural schematic diagram of a FSBB converter control device provided in an embodiment of the present application;

[0044] Figure 6 It is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0045] The following will be combined with the drawings in the embodiments of the present application to clearly describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments in the present application belong to the scope of protection of this application.

[0046] The terms "first", "second", etc. in the specification and claims of the present application are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application can be implemented in an order other than those illustrated or described herein, and the objects distinguished by "first", "second", etc. are generally of one type, and the number of objects is not limited. For example, the first object can be one or more. In addition, "and / or" in the specification and claims represents at least one of the connected objects, and the character " / " generally indicates that the objects associated with each other are in an "or" relationship.

[0047] See also Figure 1 , Figure 1 Figure 1 is a schematic diagram of the structure of the FSBB converter. The Four Switch BuckBoost (FSBB) converter can achieve bidirectional boost and buck due to its same output polarity. It has a wide range of boost and buck and is widely used in photovoltaic energy storage, battery charging and discharging, and other usage scenarios. The current control strategy of FSBB is to determine the current working mode according to the input voltage and output voltage, such as Boost mode (boost mode) or Buck mode (buck mode) or Boost-Buck mode (boost and buck mode), that is, the judgment logic and processing that need to be performed each time the mode is switched, resulting in the complexity of the control strategy logic. This complex control logic increases the response time of the FSBB converter and affects the dynamic performance of the FSBB converter.

[0048] Based on this, the embodiments of the present application provide a FSBB converter control method, device, electronic device and storage medium, aiming to reduce the complexity of the control algorithm and improve the real-time performance and efficiency of the FSBB converter.

[0049] The FSBB converter control method, device, electronic device and storage medium provided in the embodiments of the present application are described in detail below with reference to the accompanying drawings through specific embodiments and their application scenarios.

[0050] See Also Figure 1-Figure 2 , Figure 2 Schematic diagram of the flow of the FSBB converter control method provided by the embodiment of the present application. Figure 2 As shown, the FSBB converter control method includes the following steps S100 to S400.

[0051] Step S100: obtaining the output voltage of the FSBB converter.

[0052] FSBB can use a dedicated digital controller (DSP, Digital Signal Processing) with built-in control algorithm or control logic to control the switch tube and obtain the output voltage.

[0053] The FSBB converter can obtain the actual output voltage V of the FSBB converter through a sampling circuit or sensor. out The sampled signal is converted into a digital signal (usually by an analog / digital signal conversion module) and passed to a digital signal processor for subsequent calculations.

[0054] Step S200: determining a reference on-time according to the output voltage and the target output voltage of the FSBB converter.

[0055] The FSBB converter compares the actual output voltage V out Target output voltage V ref , calculate the error between the two e(t) = V ref -V out The error is processed by the proportional-integral control algorithm, and the reference on-time (duty) is output. The reference on-time is an important control parameter that determines the on-time of the switch tube.

[0056] Step S300: determining a target on-time of a switch tube in a FSBB converter in a single working cycle according to a reference on-time.

[0057] The FSBB converter then calculates the target on-time of the switch tube in the FSBB converter based on the reference on-time (the target on-time may include the on-time of one or more switch tubes in the FSBB converter). The target on-time determines the specific working time distribution of the switch tube in a single cycle. It can be understood by those skilled in the art that the remaining time except the on-time in a single working cycle of the switch tube is the off-time. In this way, by converting the deviation between the output voltage and the target value into a reference on-time, and using the reference on-time as a global variable for logical determination and basic variable for value assignment, the on-time of the switch tube in a single working cycle can be directly determined without judging the working mode, which significantly simplifies the control logic.

[0058] Step S400: Controlling the on and off of the switch tube in the FSBB converter according to the target on time of the switch tube.

[0059] The FSBB converter can convert the calculated target on-time into a control signal, and control the actual on and off of the switch tubes (S1, S2, S3, S4) through the driving circuit to adjust the output voltage to approach the target output voltage.

[0060] Those skilled in the art can understand that the FSBB converter controls the on and off of a certain switch tube by using the on time corresponding to the switch tube in the target on time. For example, the target on time includes the on time of S1, the on time of S2, the on time of S3 and the on time of S4. Then, the FSBB converter uses the on time of S1 to control the on and off of S1, uses the on time of S2 to control the on and off of S2, uses the on time of S3 to control the on and off of S3, and uses the on time of S4 to control the on and off of S4.

[0061] Through the above steps S100-S400, the FSBB converter calculates the reference on-time directly based on the deviation between the output voltage and the target output voltage, and uses this as the only core control variable, without the need for complex judgment logic and mode selection during mode switching. The FSBB converter uses the reference on-time to directly determine the target on-time of the switch tube in a single working cycle, simplifying the control logic. Compared with the traditional solution of controlling the switch tube separately by judging the mode switching logic (such as Buck, Boost or Buck-Boost mode), the FSBB converter no longer relies on mode judgment, but realizes automatic switching of the three modes through dynamic adjustment of unified control variables. In this way, the response speed of the FSBB converter in the face of input voltage or load changes is significantly improved, the output voltage is adjusted more quickly and smoothly, and the complexity of the control algorithm is reduced, which improves the real-time performance and efficiency of the FSBB converter.

[0062] In some embodiments, the target on-time includes the on-time of the buck working tube in the FSBB converter and the on-time of the buck freewheeling tube in the FSBB converter. Determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time includes:

[0063] When the reference on-time is less than or equal to the first on-time, the reference on-time is used as the on-time of the buck working tube, wherein the first on-time is the maximum on-time of the buck working tube in a single working cycle when the FSBB converter performs buck operation;

[0064] The conduction time of the buck freewheeling tube is determined according to the conduction time of the buck working tube.

[0065] It can be understood by those skilled in the art that the step-down working tube in the FSBB converter is the step-down working tube of the FSBB converter. in >V out ) is the working tube (i.e. S1) in the FSBB converter, and the buck freewheeling tube in the FSBB converter is the freewheeling tube (i.e. S2) of the FSBB converter during the buck process.

[0066] In this embodiment, to achieve the buck control of the FSBB converter, the target on-time includes the on-time of the buck working tube and the on-time of the buck freewheeling tube, that is, the control objects are the buck working tube and the buck freewheeling tube. The FSBB converter determines the on-time distribution of the buck working tube and the buck freewheeling tube in a single working cycle by comparing the reference on-time with the first on-time, thereby achieving the stable output of the FSBB converter in the buck working state.

[0067] Specifically, when the reference on-time is less than or equal to the first on-time, it means that the FSBB converter needs to perform step-down operation, and the FSBB converter uses the reference on-time as the on-time of the step-down working tube. The first on-time is the maximum on-time allowed by the step-down working tube in a single working cycle, which is used to limit the maximum output voltage range in the step-down mode to prevent the output voltage from exceeding the design value. Subsequently, according to the duration distribution relationship within the working cycle, the on-time of the step-down freewheeling tube is calculated by the on-time of the step-down working tube to ensure the alternating operation of the working tube and the freewheeling tube under step-down operation, and realize continuous power supply to the load. It can be understood by those skilled in the art that due to the working characteristics of the working tube and the freewheeling tube (the freewheeling tube is turned off when the working tube is turned on, and the freewheeling tube is turned on when the working tube is turned off), the on-time of the freewheeling tube is the duration of a single working cycle (the inverse of the frequency) minus the on-time of the working tube.

[0068] In this way, the FSBB converter can effectively utilize the reference on-time in the step-down operation to make the step-down operation proceed smoothly. At the same time, it limits the maximum on-time of the step-down working tube to avoid voltage output exceeding the design range, improve the safety and stability of the FSBB converter, and maintain the stable operation of the FSBB converter by reasonably allocating the on-time.

[0069] Exemplarily, the first on-time BUCK_MAX_DUTY=8μs, the reference on-time duty=7μs, the working period Period=10μs, duty=7μs≤BUCK_MAX_DUTY=8μs, so the on-time of the buck working tube S1 is taken as the reference on-time, that is: S1_T_on=duty=7μs, and the on-time of the buck freewheeling tube S2 is S2_T_on=Period-S1_T_on=10μs-7μs=3μs. Finally, the on-time of the buck working tube in a single working cycle is 7μs, and the on-time of the buck freewheeling tube in a single working cycle is 3μs.

[0070] In some embodiments, the target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter. Determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes:

[0071] When the reference on-time is less than or equal to the first on-time, the second on-time is determined as the on-time of the boost working tube, wherein the second on-time is the minimum on-time of the boost working tube in a single working cycle when the FSBB converter performs boost operation;

[0072] The conduction time of the boost freewheeling tube is determined according to the conduction time of the boost working tube.

[0073] It can be understood by those skilled in the art that the boost working tube in the FSBB converter is the FSBB converter in the boost process (V out >V in ) in the FSBB converter, and the buck freewheeling tube in the FSBB converter is the freewheeling tube (i.e., S3) of the FSBB converter during the buck process.

[0074] When the reference on-time is less than or equal to the first on-time, it means that the FSBB converter needs to perform a step-down operation. At this time, the output voltage is determined by the on-time of the step-down working tube, and the boost working tube has no effect on the output voltage. Under normal circumstances, when the FSBB converter needs to perform a step-down operation, the boost working tube is only turned on for a very short charging time in a single working cycle and then returns to shutdown.

[0075] In this embodiment, in order to achieve smooth switching between the buck operation and the boost operation of the FSBB converter, the target conduction duration also includes the conduction duration of the boost working tube and the conduction duration of the boost freewheeling tube. Specifically, when the reference conduction duration is less than or equal to the first conduction duration, the FSBB converter uses the second conduction duration as the conduction duration of the boost working tube. The second conduction duration is the minimum conduction duration allowed by the boost working tube in a single working cycle during the boost operation. In this embodiment, the second conduction duration is used as the conduction duration of the boost working tube during the buck operation to ensure that the boost working tube can be quickly connected to work during the buck-boost switching process to prevent the boost start-up failure or the instability of the output voltage due to insufficient conduction duration. By limiting the conduction duration of the boost working tube to the second conduction duration, the FSBB converter can achieve smooth switching between buck-boost. Subsequently, according to the conduction duration of the boost working tube, combined with the duration distribution relationship within the cycle, the conduction duration of the boost freewheeling tube is calculated to ensure the continuity of the load power supply.

[0076] In this way, the FSBB converter can avoid transient fluctuations in the output voltage during the buck-boost switching process, improve the dynamic performance of the FSBB converter, and ensure the smoothness and reliability of the mode switching.

[0077] Exemplarily, the duty cycle Period = 10 μs, the second on-time BOOST_MIN_DUTY = 2 μs, and the reference on-time duty = 1.5 μs. duty = 1.5 μs ≤ BOOST_MIN_DUTY = 2 μs. In order to achieve smooth mode switching, the on-time of the boost working tube adopts the second on-time, that is, S4_T_on = BOOST_MIN_DUTY = 2 μs, and the on-time of the boost freewheeling tube is: S3_T_on = Period - S4_T_on = 10 μs - 2 μs = 8 μs. Finally, the on-time of the boost working tube in a single duty cycle is 2 μs, and the on-time of the boost freewheeling tube in a single duty cycle is 8 μs. The second on-time BOOST_MIN_DUTY is used to ensure that the boost working tube can start quickly when switching to the boost working state, effectively alleviating the inductor current fluctuation and output voltage instability problems that may be caused by the boost-boost switching, and achieving a smooth transition of the mode.

[0078] In some embodiments, the target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter. Determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes:

[0079] When the reference on-time is greater than the first on-time, the sum of the first difference and the second on-time is used as the on-time of the boost working tube, wherein the first difference is the difference between the reference on-time and the first on-time, and the second on-time is the minimum on-time of the boost working tube in a single working cycle during the boosting;

[0080] The conduction time of the boost freewheeling tube is determined according to the conduction time of the boost working tube.

[0081] In this embodiment, in order to realize the boost working process of the FSBB converter, the target on-time also includes the on-time of the boost working tube and the on-time of the boost freewheeling tube.

[0082] Specifically, when the reference on-time is greater than the first on-time, it indicates that the FSBB converter needs to perform a boost operation. The FSBB converter determines the on-time of the boost working tube by calculating the difference between the reference on-time and the first on-time (i.e., the first difference) and adding it to the minimum on-time of the boost working tube during the boost process (i.e., the second on-time, BOOST_MIN_DUTY). The first difference reflects the portion of the current reference on-time that exceeds the first on-time, and is used to control the additional energy demand during the boost process, while the second on-time is used to ensure the minimum on-time of the boost working tube in the boost mode, thereby maintaining the stability and boost capability of the system. According to the on-time of the boost working tube, combined with the duration distribution relationship of the working cycle, the on-time of the boost freewheeling tube is dynamically determined to ensure the continuity of the inductor charging and discharging and the stability of the load power supply in the boost mode.

[0083] Through this on-time distribution method, the FSBB converter can smoothly switch to the boost state when the reference on-time exceeds the first on-time. If the reference on-time is less than or equal to the first on-time, the on-time of the boost working tube is set to the second on-time, indicating that the boost working tube is ready to enter the boost operation. In this way, when the reference on-time increases to be greater than the first on-time, the method of using the sum of the first difference and the second on-time as the on-time of the boost working tube adopted in this embodiment can also achieve a smooth transition of the buck-boost switching, while avoiding transient fluctuations in the output voltage, and improving the reliability and dynamic performance of the FSBB converter.

[0084] Exemplarily, the duty cycle Period=10 μs, the first on-time BUCK_MAX_DUTY=8 μs, the second on-time BOOST_MIN_DUTY=2 μs, and the reference on-time duty=9 μs.

[0085] The first difference = duty - BUCK_MAX_DUTY = 9 μs - 8 μs = 1 μs, the on-time of the boost working tube S4_T_on = the first difference + BOOST_MIN_DUTY = 1 μs + 2 μs = 3 μs, and the on-time of the boost freewheeling tube S3_T_on = Period - S4_T_on = 10 μs - 3 μs = 7 μs.

[0086] Finally, the conduction time of the boost working tube in a single working cycle is 3μs, and the conduction time of the boost freewheeling tube in a single working cycle is 7μs. This time distribution method can not only meet the energy requirements of the reference conduction time for the boost mode, but also ensure the smoothness of the mode switching and the reliability of the boost process by introducing the minimum conduction time BOOST_MIN_DUTY, thus achieving smooth adjustment of the output voltage.

[0087] In some implementations, determining a target on-time of a switch tube in a FSBB converter in a single working cycle according to a reference on-time also includes:

[0088] When the reference on-time is greater than the first on-time, the first on-time is used as the on-time of the step-down working tube;

[0089] The conduction time of the buck freewheeling tube is determined according to the conduction time of the buck working tube.

[0090] In this embodiment, when the reference on-time is greater than the first on-time, it indicates that the FSBB converter needs to perform a boost operation. At this time, the output voltage is determined by the on-time of the boost working tube, and the buck working tube has no effect on the output voltage. Under normal circumstances, when the FSBB converter needs to perform a boost operation, the buck working tube is only turned on for a very short charging time in a single working cycle and then returns to shutdown.

[0091] In this embodiment, in order to achieve smooth switching between the boost operation and the buck operation of the FSBB converter, specifically, when the reference on-time is greater than the first on-time, the FSBB converter uses the first on-time as the on-time of the buck working tube. The first on-time is the maximum on-time allowed for the buck working tube in a single working cycle during the buck operation. In this embodiment, the first on-time is used as the on-time of the buck working tube during the boost operation to ensure that the buck working tube can quickly switch to work during the buck-boost switching process.

[0092] In this way, when the reference on-time exceeds the first on-time, the FSBB converter can effectively limit the on-time of the buck working tube, ensure the smooth regulation of the output voltage during mode switching, and improve the dynamic performance and operational reliability of the FSBB converter. By limiting the on-time of the buck working tube, the FSBB converter can gradually reduce the inductor charging time when switching from the boost process to the buck process, avoiding the overshoot or instability of the output voltage caused by the sudden change of the on-time, thereby achieving smooth switching from boost to buck. At the same time, according to the on-time of the buck working tube, the on-time of the buck freewheeling tube is dynamically adjusted. The on-time of the buck freewheeling tube complements the buck working tube to ensure the continuity of the inductor current and the stability of the load power supply.

[0093] For example, the duty cycle Period = 10 μs, the first on-time BUCK_MAX_DUTY = 8 μs, and the reference on-time duty = 9 μs. Because duty = 9 μs> BUCK_MAX_DUTY = 8 μs, in order to achieve smooth switching from boost mode to buck mode, the on-time of the buck working tube is limited to the first on-time.

[0094] That is: S1_T_on=BUCK_MAX_DUTY=8μs, S2_T_on=Period-S1_T_on=10μs-8μs=2μs.

[0095] Finally, the conduction time of the buck working tube in a single working cycle is 8μs, and the conduction time of the buck freewheeling tube in a single working cycle is 2μs. By adopting the first conduction time as the conduction time of the buck working tube, the FSBB converter can smoothly switch from the boost state to the buck state, avoiding transient fluctuations in the output voltage or discontinuous inductor current, thereby achieving the stability of the boost-boost switching and the precise regulation of the output voltage.

[0096] See also Figure 3 , Figure 3 : is a flow logic diagram of the FSBB converter control method provided in the embodiment of the present application. Combining the above multiple implementation modes, the FSBB converter control method provided in the embodiment of the present application can be described as follows (for the sake of ease of understanding, the dead time T_deadtime that needs to be considered in the actual design process is not mentioned in the description):

[0097] First, duty (reference on-time) is obtained by calculation, and duty is compared with BUCK_MAX_DUTY (first on-time). If duty is less than or equal to BUCK_MAX_DUTY, then the on-time of the buck working tube S1_T_on = duty (all duty is assigned to S1_T_on), the on-time of the buck freewheeling tube S2_T_on = Period-duty (Period is the duration of the working cycle), the on-time of the boost freewheeling tube S3_T_on = Period-BOOST_MIN_DUTY, and the on-time of the boost working tube S4_T_on = BOOST_MIN_DUTY (second on-time);

[0098] If duty is greater than BUCK_MAX_DUTY, S1_T_on = BUCK_MAX_DUTY (the BUCK_MAX_DUTY part of duty is assigned to S1_T_on), S2_T_on = Period - BUCK_MAX_DUTY, S3_T_on = Period - (Duty - BUCK_MAX_DUTY) - BOOST_MIN_DUTY, S4_T_on = Duty - BUCK_MAX_DUTY + BOOST_MIN_DUTY (the part of duty except BUCK_MAX_DUTY is assigned to S4_T_on which already includes BOOST_MIN_DUTY).

[0099] In some embodiments, the method further comprises:

[0100] When the reference conduction time is less than or equal to the first conduction time, the operating frequencies of the buck working tube and the buck freewheeling tube are controlled to be the first frequency, and the operating frequencies of the boost working tube and the boost freewheeling tube are controlled to be the second frequency;

[0101] When the reference conduction time is greater than the first conduction time, the operating frequencies of the buck working tube and the buck freewheeling tube are controlled to be a third frequency, and the operating frequencies of the boost working tube and the boost freewheeling tube are controlled to be a fourth frequency;

[0102] The first frequency is greater than the second frequency, the first frequency is greater than the third frequency, the fourth frequency is greater than the third frequency, and the fourth frequency is greater than the second frequency.

[0103] In this embodiment, in order to reduce switching losses and improve the overall efficiency of the FSBB converter, the control method dynamically adjusts the operating frequencies of the buck working tube, the buck freewheeling tube, the boost working tube and the boost freewheeling tube according to the relationship between the reference conduction time and the first conduction time, so that the FSBB converter can optimize both performance and energy consumption under different working conditions.

[0104] Specifically, when the reference on-time is less than or equal to the first on-time, the FSBB converter operates in the buck working state. At this time, in order to ensure the output voltage stability in the buck mode, the buck working tube and the buck freewheeling tube operate at the first frequency (higher frequency) to improve the response speed and reduce the ripple of the output voltage. At the same time, the boost working tube and the boost freewheeling tube operate at the second frequency (lower frequency), maintaining only the necessary minimum on-time to reduce the energy loss caused by the high-frequency switching action.

[0105] When the reference on-time is greater than the first on-time, the FSBB converter enters the boost state or the buck-boost state. At this time, the frequency of the buck working tube and the buck freewheeling tube is reduced to the third frequency (lower frequency) to reduce unnecessary switching losses; the frequency of the boost working tube and the boost freewheeling tube is increased to the fourth frequency (higher frequency) to quickly respond to the boost demand and improve the energy transfer efficiency during the boost process.

[0106] Through this frequency regulation strategy, the FSBB converter can dynamically optimize the switching frequency distribution under different working conditions: high frequency operation is used for fine control, and low frequency operation is used to reduce switching losses. This method not only effectively reduces the energy loss of the FSBB converter, but also improves the overall efficiency of the converter under different working conditions.

[0107] In some embodiments, the method further comprises:

[0108] When the reference on-time is less than or equal to the first on-time, the second on-time is used as the on-time of the boost working tube, and the target on-time of the boost freewheeling tube is determined according to the on-time of the boost working tube;

[0109] When the reference on-time is greater than the first on-time, the difference between the first on-time and the preset adjustment time is used as the on-time of the buck working tube, so that the first output power of the FSBB converter is greater than the second output power, wherein the first output power is the output power before the working frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase, and the second output power is the output power after the working frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase;

[0110] The conduction time of the buck freewheeling tube is determined according to the conduction time of the buck working tube.

[0111] In this embodiment, in order to avoid oscillation of the FSBB converter due to output power imbalance during mode switching, the FSBB converter dynamically adjusts the conduction time of the boost working tube and the buck working tube to achieve a smooth transition of the output power before and after switching.

[0112] Specifically, the control method provided in this embodiment is Figure 3 Compared with the control method described in , the only difference is that when the reference on-time is greater than the first on-time (duty is greater than BUCK_MAX_DUTY), the difference between the first on-time and the preset adjustment time (ADJUST_DUTY) is set to the on-time of the buck working tube (S1_T_on = BUCK_MAX_DUTY-ADJUST_DUTY, and the working time of the buck freewheeling tube S2_T_on = Period-BUCK_MAX_DUTY+ADJUST_DUTY can be obtained at the same time). That is, by shortening the on-time of the buck working tube, the output power is controlled to be gradually reduced. That is, at the time point when duty continues to increase and is equal to BUCK_MAX_DUTY (the time point when the buck-boost switching is about to be performed), ensure that the output power after the frequency switching (the second output power) is less than the output power before the frequency switching (the first output power). Subsequently, according to the on-time of the buck working tube, the target on-time of the buck freewheeling tube is dynamically calculated to maintain the energy balance in the buck mode.

[0113] Figure 4 is a schematic diagram of output power variation before and after frequency switching provided by an embodiment of the present application, such as Figure 4 As shown, the first power is 200KHz, the second power is 100KHz, the third power is 100KHz, and the fourth power is 200KHz. Before and after the buck-boost working state is switched, S1, S2, S3, and S4 are frequency-converted. In the process of duty from less than or equal to BUCK_DUTY_MAX to greater than BUCK_DUTY_MAX, the output power will increase. Under the same load, the output voltage will rise. In this way, the voltage feedback loop will reduce the duty (that is, the duty calculated by the proportional-integral control algorithm will be reduced), and the circuit will continue to oscillate. By introducing ADJUST_DUTY, the first output power is greater than the second output power, ensuring that the carrying capacity before switching is greater than the carrying capacity after switching, and avoiding oscillation.

[0114] Those skilled in the art will appreciate that the preset adjustment duration needs to be tested and calibrated in advance to ensure that the first output power is greater than the second output power.

[0115] In this way, the FSBB converter can adjust the distribution of output power before and after switching to avoid output voltage oscillation caused by power mutation.

[0116] See also Figure 5, is a structural diagram of a FSBB converter control device provided in an embodiment of the present application. In a second aspect of an embodiment of the present application, a FSBB converter control device 10 is provided. The device 10 includes:

[0117] An acquisition module 11, used for acquiring the output voltage of the FSBB converter;

[0118] A first determination module 12, configured to determine a reference on-time according to the output voltage and a target output voltage of the FSBB converter;

[0119] A second determination module 13 is used to determine a target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time;

[0120] The control module 14 is used to control the switch tube in the FSBB converter to be turned on and off according to the target on time of the switch tube.

[0121] The FSBB converter control device 10 provided in the second aspect of the embodiment of the present application can implement each process implemented in the above-mentioned method embodiment and achieve the same beneficial effects. To avoid repetition, it will not be described here.

[0122] See also Figure 6 , is a structural diagram of an electronic device provided in an embodiment of the present application. In a third aspect, an embodiment of the present application provides an electronic device 1000, including a processor 1100 and a memory 1200. The memory 1200 stores machine executable instructions that can be executed by the processor 1100. The processor 1100 can execute the machine executable instructions to implement the above-mentioned FSBB converter control method.

[0123] A fourth aspect of an embodiment of the present application provides a machine-readable storage medium, on which instructions are stored. When the instructions are executed by a processor, the processor implements the above-mentioned FSBB converter control method.

[0124] In some implementations, the embodiments of the present application further provide a computer program product, including a computer program, which implements the FSBB converter control method according to the above implementation when executed by a processor.

[0125] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.

[0126] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to generate a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including an instruction device, which implements the functions specified in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 These computer program instructions can also be loaded onto a computer or other programmable data processing device, so that a series of operation steps are executed on the computer or other programmable device to produce a computer-implemented process, so that the instructions executed on the computer or other programmable device provide for implementing the process in the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.

[0127] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0128] The memory may include non-permanent memory in a computer-readable medium, random access memory (RAM) and / or non-volatile memory in the form of read-only memory (ROM) or flash RAM. The memory is an example of a computer-readable medium.

[0129] Computer readable media include permanent and non-permanent, removable and non-removable media that can be implemented by any method or technology to store information. Information can be computer readable instructions, data structures, program modules or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technology, compact disk read-only memory (CD-ROM), digital versatile disk (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices or any other non-transmission media that can be used to store information that can be accessed by a computing device. As defined herein, computer readable media does not include temporary computer readable media (transcript media), such as modulated data signals and carrier waves.

[0130] It should also be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprises a ..." do not exclude the existence of other identical elements in the process, method, commodity or device including the elements.

[0131] The above are only embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included within the scope of the claims of the present application.

[0132] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A FSBB converter control method, characterized in that: The method comprises: Obtaining an output voltage of the FSBB converter; determining a reference on-time according to the output voltage and a target output voltage of the FSBB converter; Determine a target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time; The switch tube in the FSBB converter is controlled to be turned on and off according to the target on time of the switch tube.

2. The method according to claim 1, characterized in that The target on-time includes the on-time of the buck working tube in the FSBB converter and the on-time of the buck freewheeling tube in the FSBB converter. The step of determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time includes: When the reference on-time is less than or equal to the first on-time, the reference on-time is used as the on-time of the buck working tube, wherein the first on-time is the maximum on-time of the buck working tube in a single working cycle when the FSBB converter performs buck operation; The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

3. The method according to claim 2, characterized in that The target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter. The step of determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes: When the reference on-time is less than or equal to the first on-time, a second on-time is determined as the on-time of the boost working tube, wherein the second on-time is the minimum on-time of the boost working tube in a single working cycle when the FSBB converter performs boost operation; The conduction time length of the boost freewheeling tube is determined according to the conduction time length of the boost working tube.

4. The method according to claim 2, characterized in that: The target on-time also includes the on-time of the boost working tube in the FSBB converter and the on-time of the boost freewheeling tube in the FSBB converter. The step of determining the target on-time of the switch tube in the FSBB converter in a single working cycle according to the reference on-time also includes: In the case where the reference on-time is greater than the first on-time, the sum of the first difference and the second on-time is used as the on-time of the boost working tube, wherein the first difference is the difference between the reference on-time and the first on-time, and the second on-time is the minimum on-time of the boost working tube in a single working cycle during boosting; The conduction time length of the boost freewheeling tube is determined according to the conduction time length of the boost working tube.

5. The method according to claim 4, characterized in that The step of determining a target on-time of a switch tube in the FSBB converter within a single working cycle according to the reference on-time also includes: When the reference on-time is greater than the first on-time, the first on-time is used as the on-time of the step-down working tube; The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

6. The method according to claim 4, characterized in that The method further comprises: When the reference conduction time is less than or equal to the first conduction time, controlling the operating frequencies of the step-down working tube and the step-down freewheeling tube to be a first frequency, and controlling the operating frequencies of the boost working tube and the boost freewheeling tube to be a second frequency; When the reference conduction time is greater than the first conduction time, controlling the operating frequencies of the step-down working tube and the step-down freewheeling tube to be a third frequency, and controlling the operating frequencies of the boost working tube and the boost freewheeling tube to be a fourth frequency; The first frequency is greater than the second frequency, the first frequency is greater than the third frequency, the fourth frequency is greater than the third frequency, and the fourth frequency is greater than the second frequency.

7. The method according to claim 6, characterized in that The method further comprises: When the reference on-time is less than or equal to the first on-time, the second on-time is used as the on-time of the boost working tube, and the target on-time of the boost freewheeling tube is determined according to the on-time of the boost working tube; In the case where the reference on-time is greater than the first on-time, the difference between the first on-time and the preset adjustment time is used as the on-time of the buck working tube, so that the first output power of the FSBB converter is greater than the second output power, wherein the first output power is the output power before the operating frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase, and the second output power is the output power after the operating frequency of the buck working tube is switched from the first frequency to the third frequency when the reference on-time is equal to the first on-time and the reference on-time continues to increase; The conduction time length of the step-down freewheeling tube is determined according to the conduction time length of the step-down working tube.

8. A FSBB converter control device, characterized in that: The device comprises: An acquisition module, used for acquiring the output voltage of the FSBB converter; A first determination module, configured to determine a reference on-time according to the output voltage and a target output voltage of the FSBB converter; A second determination module is used to determine a target on-time of the switch tube in the FSBB converter within a single working cycle according to the reference on-time; A control module is used to control the switching tube in the FSBB converter to be turned on and off according to the target on time of the switching tube.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores a program or instruction that can be run on the processor, and when the program or instruction is executed by the processor, the FSBB converter control method according to any one of claims 1 to 7 is implemented.

10. A machine-readable storage medium, characterized in that: The machine-readable storage medium stores instructions, which, when executed by a processor, enable the processor to implement the FSBB converter control method according to any one of claims 1 to 7.

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