Periodic energy control method, device and system of DC-DC converter

Abstract

The invention relates to the field of direct current-direct current converters, and provides a periodic energy control method, device and system for a direct current-direct current converter, and the method comprises the steps: determining a port which has a switching tube state characteristic and is close to output as a target port according to a topological structure of the direct current-direct current converter; calculating the output energy of the target port in a switching period according to the voltage and current of the DC-DC converter; according to the output energy, determining the switch-on time of the switch tube required for reaching the target energy; and controlling the switch tube of the DC-DC converter according to the switch tube conduction time. According to the invention, the overshoot of the DC-DC converter can be effectively suppressed, and the controllability, reliability and sustainability of the system are improved. Meanwhile, the requirement for the level of capacitance or inductance in the DC-DC converter can be lowered, and then the cost is lowered.

Description

Technical Field

[0001] The present invention relates to the field of DC-DC converters, and in particular to a method, device and system for periodic energy control of a DC-DC converter. Background Art

[0002] DC-DC converters are common circuits for power conversion and are widely used in power grids, laptops, photovoltaic power generation, etc. In addition, due to the convenience of output regulation, DC-DC converters are often cascaded with the input or output of other power conversion devices, such as resonant converters and wireless power transmission (WPT) systems. For example, buck and boost converters are added before the inverter and after the rectifier to track the maximum efficiency point.

[0003] The high performance of the DC-DC converter depends on its control strategy, which should meet the requirements of different application scenarios, i.e., dynamic response or stable output. In the prior art, the DC-DC converter control method uses the duty cycle of the switch tube drive signal as the control variable, and controls the output of the DC-DC converter by adjusting the duty cycle. It is easy to overshoot when the load changes, which endangers the reliability of the DC-DC converter. In addition, the existing DC-DC converter control method also has the problem of poor sustainability and high requirements for the power level of the capacitor or inductor in the DC-DC converter, which leads to high cost. Summary of the invention

[0004] This article aims to solve the problems in the prior art that the DC-DC converter control strategy is prone to overshoot, has poor reliability and sustainability, and high cost.

[0005] In order to solve the above technical problems, this paper provides a periodic energy control method of a DC-DC converter, comprising:

[0006] According to the topological structure of the DC-DC converter, a port having a switch state characteristic and close to the output is determined as a target port;

[0007] Calculate the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter;

[0008] According to the output energy, determine the switch tube conduction time required to achieve the target energy;

[0009] The switch tube of the DC-DC converter is controlled according to the conduction time of the switch tube.

[0010] In a further embodiment, according to the topology of the DC-DC converter, determining a port having a switch state characteristic and close to the output as a target port includes:

[0011] According to the topological structure of the DC-DC converter, determine all the ports in the DC-DC converter;

[0012] Preliminarily select the ports whose current or voltage changes due to the switching action from the determined ports;

[0013] From the initially screened ports, select the port close to the output as the target port.

[0014] In a further embodiment, calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter includes:

[0015] Collecting current and voltage of target port in DC-DC converter;

[0016] Based on the collected current and voltage, determine the expression of the output energy of the target port in one switching cycle.

[0017] In a further embodiment, the following formula is used to represent the output energy of the target port in a switching cycle:

[0018]

[0019] Among them, E p is the output energy of the target port in one switching cycle, u p (t) is the voltage at time t, i p (t) is the current at time t, t is the time, T s is the switching cycle.

[0020] In a further embodiment, calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter further includes:

[0021] According to the state of the switch tube in the DC-DC converter, the state equation of the system when the switch tube is turned on is established;

[0022] Substituting the state equation into the expression of the output energy to obtain a simplified energy expression;

[0023] The simplified energy expression is used as the final output energy expression.

[0024] In a further embodiment, for a step-down DC-DC converter, the simplified energy expression is:

[0025]

[0026] For a boost DC-DC converter, the simplified expression for energy is:

[0027]

[0028] For a buck-boost DC-DC converter, the simplified expression for energy is:

[0029]

[0030] Among them, E D is the target port output energy, U i is the input voltage, Uo is the output voltage, k L is the inductor current slope, I Lmin is the minimum inductor current, L b is the inductor inductance, E S is the target port output energy, t on and t off is the on-time and off-time of the switch tube.

[0031] In a further embodiment, for a step-down DC-DC converter, the switch on time is calculated using the following formula:

[0032]

[0033] For a boost DC-DC converter, the switch on time is calculated using the following formula:

[0034] t on =T s -t off

[0035] For a buck-boost DC-DC converter, the switch on time is calculated using the following formula:

[0036]

[0037] Among them, I Lmin is the minimum inductor current, k L is the inductor current slope, E tar is the target energy, U o is the output voltage, T s is the switching cycle, U i is the input voltage, t on and t off For duration.

[0038] On the other hand, the present invention provides a periodic energy control device of a DC-DC converter, comprising:

[0039] A port screening unit, used to determine a port having a switch state characteristic and close to an output as a target port according to a topological structure of the DC-DC converter;

[0040] An energy calculation unit, used for calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter;

[0041] A switch tube conduction time calculation unit, used to determine the switch tube conduction time required to achieve the target energy according to the output energy;

[0042] A control unit is used to control the switch tube of the DC-DC converter according to the conduction time of the switch tube.

[0043] In another aspect, the present invention provides a periodic energy control system of a DC-DC converter, comprising: a DC-DC converter, a collection device and a controller;

[0044] The acquisition device is connected to the DC-DC converter and is used to acquire the voltage and current of the DC-DC converter;

[0045] The controller is connected to the acquisition device and the DC-DC converter, and is used to execute the method described in any of the above embodiments.

[0046] On the other hand, the present invention provides a computer storage medium having a computer program stored thereon, and when the computer program is executed by a processor of a computer device, the method described in any of the above embodiments is implemented.

[0047] The periodic energy control method, device and system of the DC-DC converter provided in this paper are as follows: according to the topological structure of the DC-DC converter, a port having a switch state characteristic and close to the output is determined as the target port; according to the voltage and current of the DC-DC converter, the output energy of the target port in a switching cycle is calculated; according to the output energy, the switch tube conduction time required to achieve the target energy is determined; according to the switch tube conduction time, the switch tube of the DC-DC converter is controlled, and the output energy of the target port is used as the control variable, so that the energy consumed by the load comes entirely from the output energy of the port, which can effectively suppress the overshoot of the DC-DC converter, improve the controllability, reliability and sustainability of the system, and at the same time, reduce the requirements for the capacitor or inductor level in the DC-DC converter, thereby reducing the cost. The DC-DC converter system provided in this paper can be applied to other power electronic topologies, for example: a static or dynamic wireless power transmission system with a DC-DC converter.

[0048] In order to make the above and other purposes, features and advantages of this article more obvious and easy to understand, the following is a detailed description in conjunction with the embodiments and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the technical solutions in the embodiments of this article or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of this article. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0050] Figure 1 A flow chart showing a periodic energy control method of a DC-DC converter according to an embodiment of the present invention is shown;

[0051] Figure 2A A topological structure diagram of a step-down DC-DC converter according to an embodiment of this invention is shown;

[0052] Figure 2B A topological structure diagram of a boost DC-DC converter according to an embodiment of this invention is shown;

[0053] Figure 2C A topological structure diagram of a buck-boost DC-DC converter according to an embodiment of the present invention is shown;

[0054] Figure 3 A flow chart showing a target port determination process according to an embodiment of the present invention is shown;

[0055] Figure 4 A flowchart showing the process of determining the output energy expression of the embodiment of this invention

[0056] Figure 5 The structure diagram of the periodic energy control device of the DC-DC converter in the embodiment of this invention is shown;

[0057] Figure 6 The structure diagram of the periodic energy control system of the DC-DC converter in the embodiment of this article is shown;

[0058] Figure 7 A structural diagram of a computer device according to an embodiment of this invention is shown.

[0059] Description of the accompanying symbols:

[0060] 501, port screening unit;

[0061] 502. Energy calculation unit;

[0062] 503, switch tube conduction time calculation unit;

[0063] 504. Control unit;

[0064] 601, DC-DC converter;

[0065] 602. Acquisition equipment (analog circuit);

[0066] 603, controller;

[0067] 702. Computer equipment;

[0068] 704, processor;

[0069] 706. Memory;

[0070] 708, driving mechanism;

[0071] 710, input / output module;

[0072] 712. Input devices;

[0073] 714. Output devices;

[0074] 716. Presentation equipment;

[0075] 718. Graphical user interface;

[0076] 720, network interface;

[0077] 722. Communication link;

[0078] 724. Communication bus. DETAILED DESCRIPTION

[0079] The following will be combined with the drawings in the embodiments of this article to clearly and completely describe the technical solutions in the embodiments of this article. Obviously, the described embodiments are only part of the embodiments of this article, not all of the embodiments. Based on the embodiments of this article, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this article.

[0080] It should be noted that the terms "including" and "having" and any variations thereof in the specification and claims of this document and the above-mentioned drawings are intended to cover non-exclusive inclusions. For example, a process, method, apparatus, product or equipment that includes a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units that are not explicitly listed or are inherent to these processes, methods, products or equipment.

[0081] This specification provides method operation steps as described in the embodiments or flow charts, but more or fewer operation steps may be included based on routine or non-creative work. The order of steps listed in the embodiments is only one way of executing the order of many steps and does not represent the only execution order. When the system or device product is executed in practice, it can be executed in the order of the method shown in the embodiments or the drawings or in parallel.

[0082] The control strategy of DC-DC converter in the prior art has the problems of poor reliability and sustainability and high cost. In order to solve this technical problem, a periodic energy control method of DC-DC converter is provided, which is applicable to various types of DC-DC converters, such as buck DC-DC converter, boost DC-DC converter, buck-boost DC-DC converter, etc.

[0083] Specifically, Figure 1 As shown, the periodic energy control method of the DC-DC converter includes:

[0084] Step 101, according to the topology of the DC-DC converter, determining a port having a switch state characteristic and close to the output as a target port;

[0085] Step 102, calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter;

[0086] Step 103, determining the switch on time required to reach the target energy according to the output energy;

[0087] Step 104: Control the switch tube of the DC-DC converter according to the conduction time of the switch tube.

[0088] This embodiment uses the output energy of the target port as the control variable, so that all the energy consumed by the load comes from the output energy of the port, which can effectively suppress the overshoot of the DC-DC converter and improve the controllability, reliability and sustainability of the system. At the same time, the requirements for the capacitor or inductor level in the DC-DC converter can be reduced, thereby reducing costs. The DC-DC converter system provided in this article can be applied to other power electronic topologies, for example: using a static or dynamic wireless power transmission system with a DC-DC converter.

[0089] In step 101, a DC-DC converter is a converter to be controlled. The topology of the DC-DC converter can be represented by a circuit diagram of the converter, such as FIG. 2A to FIG. 2C As shown, the topological diagrams of the step-down DC-DC converter, the step-up DC-DC converter and the step-down-boost DC-DC converter are respectively shown, including the power supply access terminal, the switch tube, the capacitor, the inductor and the load access terminal.

[0090] A port with switch state characteristics refers to a port whose voltage or current can reflect the change caused by the switch action. Figure 3 As shown, the implementation process of this step includes:

[0091] Step 301, according to the topology of the DC-DC converter, determine all ports in the DC-DC converter, specifically, the energy port selected for control should have the characteristics of being as close to the output terminal as possible and the port voltage or current being able to reflect the switching change in each switching cycle;

[0092] Step 302, preliminarily screening out ports whose current or voltage changes due to switch action from the determined ports;

[0093] Step 303: From the initially screened ports, select a port close to the output as the target port.

[0094] by Figure 2A For example, U in ,u Db , and U o is the input voltage, the voltage across the diode and the output voltage, i bi ,i L and i bo is the system input current, inductor current and output current, S b ,D b ,L b ,C o ,R o It is the switch tube, diode, inductor, filter capacitor and load resistor. Figure 2A There are three ports in E that can be used as energy ports for control. i ,E D and E o Respectively represent the energy output from port 1 (between nodes 1+ and 1-), port 2 (between nodes 2+ and 2-), and port 3 (between nodes 3+ and 3-). Port 3 is closest to the output terminal, but the port current i bo And the terminal voltage U o The switching action changes continuously, and the impact of the switching action on the energy cannot be reflected immediately. Therefore, based on the requirements for control response speed, port 3 is not suitable as an energy control port. bi There will be discontinuity due to the switching action, so this port can quickly respond to the port energy changes caused by the switching action. Similarly, the port voltage u of port 2 Db There will also be discontinuity due to the switching action, and this port can also quickly respond to the impact of the switching action on energy. Port 2 is closer to the system output than port 1. Considering the impact of device loss, port 2 is more suitable as a port for energy control.

[0095] Figure 2B and Figure 2C The symbols in Figure 2A The symbols have the same meaning, and Es is the output energy of the target port.

[0096] When the above step 102 is implemented, the current and voltage of the target port in the DC-DC converter are first collected. Specifically, the voltage and current of the DC-branch converter can be obtained by sampling the analog circuit connected to the DC-DC converter, and the digital signals of the voltage and current can be obtained by conversion of the analog-to-digital converter; then, the expression of the output energy of the target port in a switching cycle is determined according to the collected current and voltage, which is specifically shown in the following formula:

[0097]

[0098] Among them, E p is the output energy of the target port in one switching cycle, u p (t) is the voltage at time t, i p (t) is the current at time t, t is the time, T s is the switching cycle.

[0099] In a further embodiment, because the above-mentioned scoring expression of output energy requires sampling the voltage and current of the target port all the time, errors occur during the sampling and conversion process, and the error results will be accumulated in the integral result, thereby causing a significant difference between the calculated result and the actual result, affecting the calculated result of the output energy of the target port. Based on this, this paper proposes a method of simplifying the energy expression, such as Figure 4 As shown, according to the voltage and current of the DC-DC converter, the output energy of the target port in a switching cycle is calculated, including:

[0100] Step 401, collecting the current and voltage of the target port in the DC-DC converter;

[0101] Step 402, determining an expression for the energy output by the target port within a switching cycle according to the collected current and voltage;

[0102] Step 403, according to the state of the switch tube in the DC-DC converter, establish the state equation of the system when the switch tube is turned on;

[0103] Step 404, substituting the state equation into the expression of output energy determined in step 402 to obtain a simplified energy expression;

[0104] Step 405: Use the simplified energy expression as the final output energy expression.

[0105] In this embodiment, the conversion of calculating the port energy is obtained by sampling several instantaneous voltages and currents instead of integral calculation, so as to improve the robustness of the control method.

[0106] In detail, the implementation of step 401 and step 402 refers to the aforementioned step 301 and step 302.

[0107] Step 403, combining the topology of the DC-DC converter and the state of the switch tube in the DC-DC converter, establish the switch tube state equation. The prior art can be referred to. Taking the buck converter as an example, when the switch tube S b When conducting, the system state equation can be expressed as:

[0108]

[0109] Among them, L b is the inductance value of the buck converter, k L It is the switch tube S b When the inductor is turned on, the current i L The slope of the inductor current is the minimum value I L min Appears in the switch tube S b The moment of conduction, i.e. t = nT s , U bi and U bo In each switching cycle, I Lmin ,U bi , and U bo The switch tube S b The conduction instant sampling is obtained.

[0110] For example, for a step-down DC-DC converter, the energy simplified expression is:

[0111]

[0112] For a boost DC-DC converter, the simplified expression for energy is:

[0113]

[0114] For a buck-boost DC-DC converter, the simplified expression for energy is:

[0115]

[0116] Among them, E D is the target port output energy, U i is the input voltage, U o is the output voltage, k L is the inductor current slope, I Lmin is the minimum inductor current, L b is the inductor inductance, E S is the target port output energy, t on and t off They are the on-time and off-time of the switch tube respectively.

[0117] In step 103, the target energy corresponds to the output voltage or current required by the system, which can be expressed as the following formula:

[0118]

[0119] Among them, E tar ,U tar , and I tar They are the target energy, target voltage and target current of the system output. The target energy is adjusted according to the output voltage and current required by the system.

[0120] Correspondingly, the switch on time determined by step 103 is:

[0121] For a step-down DC-DC converter, the switch on-time is calculated using the following formula:

[0122]

[0123] For a boost DC-DC converter, the switch on time is calculated using the following formula:

[0124]

[0125] For a buck-boost DC-DC converter, the switch on time is calculated using the following formula:

[0126]

[0127] Among them, I Lmin is the minimum inductor current, k L is the inductor current slope, E tar is the target energy, U o is the output voltage, T s is the switching cycle, U i is the input voltage, t on and t off They are the on-time and off-time of the switch tube respectively.

[0128] In order to obtain a rational number solution in the square root calculation in the above formula, the square root must be a non-negative rational number.

[0129] The periodic energy control method of the DC-DC converter proposed in this paper is applicable to not only buck DC-DC converter, boost DC-DC converter and step-up DC-DC converter, but also other DC-DC converters. The applicable conditions include having an energy port that can respond to the switch action and the conduction time obtained based on the simplified energy expression has a rational number solution during the system operation process. The energy formula of other DC-DC converters and the process of deriving the switch tube conduction time are the same as those of the DC-DC converter in this paper, and will not be described in detail here.

[0130] Through verification of a step-down DC-DC converter, a step-up DC-DC converter and a step-up DC-DC converter, it can be seen that the present embodiment has very high accuracy in both transient and steady states.

[0131] Based on the same inventive concept, this article also provides a periodic energy control device for a DC-DC converter, as described in the following embodiments. Since the principle of solving the problem by the periodic energy control device for a DC-DC converter is similar to the periodic energy control method for a DC-DC converter, the implementation of the periodic energy control device for a DC-DC converter can refer to the periodic energy control method for a DC-DC converter, and the repeated parts will not be repeated.

[0132] Specifically, Figure 5 As shown, the periodic energy control device of the DC-DC converter includes:

[0133] The port screening unit 501 is used to determine, according to the topology of the DC-DC converter, a port having a switch state characteristic and close to the output as a target port;

[0134] The energy calculation unit 502 calculates the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter;

[0135] The switch tube conduction time calculation unit 503 is used to determine the switch tube conduction time required to achieve the target energy according to the output energy and the target energy;

[0136] The control unit 504 is used to control the switch tube of the DC-DC converter according to the conduction time of the switch tube.

[0137] This embodiment uses the output energy of the target port as the control variable, so that all the energy consumed by the load comes from the output energy of the port, which can effectively suppress the overshoot of the DC-DC converter and improve the controllability, reliability and sustainability of the system. At the same time, the requirements for the capacitor or inductor level in the DC-DC converter can be reduced, thereby reducing costs. The DC-DC converter system provided in this article can be applied to other power electronic topologies, for example: using a static or dynamic wireless power transmission system with a DC-DC converter.

[0138] In one embodiment of the present invention, a periodic energy control system of a DC-DC converter is also provided, such as Figure 6 As shown, it includes: a DC-DC converter 601, a collection device 602 and a controller 603.

[0139] The acquisition device 602 is connected to the DC-DC converter 601 and is used to acquire the voltage and current of the DC-DC converter 601;

[0140] The controller 603 is connected to the acquisition device 602 and the DC-DC converter 601 , and is used to execute the method described in any of the above embodiments to control the switch tube of the DC-DC converter 601 .

[0141] In detail, the acquisition device 602 includes an analog circuit for sampling voltage or current.

[0142] In a specific implementation, the controller 603 includes an analog-to-digital conversion unit, a switch tube conduction time calculation unit, and a drive unit. The analog-to-digital circuit is used to convert an analog signal of an analog circuit into a digital signal, the switch tube conduction time calculation unit is used to calculate the switch tube conduction time using the method described in any of the above embodiments, and the drive unit generates a drive signal according to the calculated switch tube conduction time, and the drive signal controls the switch tube of the DC-DC converter.

[0143] This embodiment provides a new idea for energy control of DC-DC converters. The current control method uses the duty cycle of the switch tube drive signal as the control target. However, this embodiment uses the output energy of the target port as the control target, which can effectively suppress the overshoot of the system and protect the safe and reliable operation of the system. By collecting the system voltage or current and combining the derived simplified energy calculation formula, the port output energy can be limited to the target energy, thereby achieving the goal of controlling the system output.

[0144] The DC-DC converter energy control system provided in this article can be applied to power modules alone, and can also be applied to DC-DC converters used in the power supply parts of data centers, smart phones, and electric vehicles. At the same time, the DC-DC converter can also be used as a submodule for system output regulation. For example, the output of a wireless power transmission system can be cascaded with a DC-DC converter to adjust the output. Therefore, the control method proposed in this invention has potential application scenarios in the field of power conversion. This article does not limit its specific application scenarios.

[0145] In one embodiment of the present invention, a computer device is also provided, such as Figure 7As shown, the computer device 702 may include one or more processors 704, such as one or more central processing units (CPUs), each of which may implement one or more hardware threads. The computer device 702 may also include any memory 706, which is used to store any kind of information such as code, settings, data, etc. Non-limitingly, for example, the memory 706 may include any one or more combinations of the following: any type of RAM, any type of ROM, flash memory device, hard disk, optical disk, etc. More generally, any memory may use any technology to store information. Further, any memory may provide volatile or non-volatile retention of information. Further, any memory may represent a fixed or removable component of the computer device 702. In one case, when the processor 704 executes an associated instruction stored in any memory or a combination of memories, the computer device 702 may perform any operation of the associated instruction. The computer device 702 also includes one or more drive mechanisms 708 for interacting with any memory, such as a hard disk drive mechanism, an optical disk drive mechanism, etc.

[0146] The computer device 702 may also include an input / output module 710 (I / O) for receiving various inputs (via input devices 712) and for providing various outputs (via output devices 714). A specific output mechanism may include a presentation device 716 and an associated graphical user interface (GUI) 718. In other embodiments, the input / output module 710 (I / O), the input device 712, and the output device 714 may not be included, and the computer device 702 may be used as a computer device in a network. The computer device 702 may also include one or more network interfaces 720 for exchanging data with other devices via one or more communication links 722. One or more communication buses 724 couple the components described above together.

[0147] The communication link 722 may be implemented in any manner, for example, through a local area network, a wide area network (e.g., the Internet), a point-to-point connection, etc., or any combination thereof. The communication link 722 may include any combination of hardwired links, wireless links, routers, gateway functions, name servers, etc. governed by any protocol or combination of protocols.

[0148] The embodiments of the present invention further provide a computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the above method are executed.

[0149] The embodiments of this document also provide a computer-readable instruction, wherein when a processor executes the instruction, the program therein causes the processor to execute the method described in any of the aforementioned embodiments.

[0150] It should be understood that in the various embodiments of this document, the size of the serial numbers of the above-mentioned processes does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of this document.

[0151] It should also be understood that in the embodiments of this article, the term "and / or" is only a description of the association relationship of the associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0152] Those of ordinary skill in the art will appreciate that the units and algorithm steps of each example described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the interchangeability of hardware and software, the composition and steps of each example have been generally described in terms of function in the above description. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this article.

[0153] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0154] In the several embodiments provided herein, it should be understood that the disclosed systems, devices and methods can be implemented in other ways. For example, the device embodiments described above are only schematic, for example, the division of the units is only a logical function division, and there may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed can be an indirect coupling or communication connection through some interfaces, devices or units, or can be electrical, mechanical or other forms of connection.

[0155] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the embodiments of this article.

[0156] In addition, each functional unit in each embodiment of this invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit may be implemented in the form of hardware or in the form of software functional unit.

[0157] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this article is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of this article. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0158] Specific embodiments are used in this article to illustrate the principles and implementation methods of this article. The description of the above embodiments is only used to help understand the methods and core ideas of this article. At the same time, for general technicians in this field, according to the ideas of this article, there will be changes in the specific implementation methods and application scopes. In summary, the content of this specification should not be understood as a limitation on this article.

Claims

1. A periodic energy control method for a DC-DC converter, characterized in that: include: According to the topological structure of the DC-DC converter, a port having a switch state characteristic and close to the output is determined as a target port; Calculate the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter; According to the output energy, determine the switch tube conduction time required to achieve the target energy; The switch tube of the DC-DC converter is controlled according to the conduction time of the switch tube.

2. The method according to claim 1, characterized in that According to the topology of the DC-DC converter, a port having switch state characteristics and close to the output is determined as a target port, including: According to the topological structure of the DC-DC converter, determine all the ports in the DC-DC converter; Preliminarily select the ports whose current or voltage changes due to the switching action from the determined ports; From the initially screened ports, select the port close to the output as the target port.

3. The method according to claim 1, characterized in that According to the voltage and current of the DC-DC converter, the output energy of the target port in a switching cycle is calculated, including: Collecting current and voltage of target port in DC-DC converter; Based on the collected current and voltage, determine the expression of the output energy of the target port in one switching cycle.

4. The method according to claim 3, characterized in that The following formula is used to express the output energy of the target port in one switching cycle: Among them, E p is the output energy of the target port in one switching cycle, u p (t) is the voltage at time t, i p (t) is the current at time t, t is the time, T s is the switching cycle.

5. The method according to claim 3, characterized in that Calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter, and also including: According to the state of the switch tube in the DC-DC converter, the state equation of the system when the switch tube is turned on is established; Substituting the state equation into the expression of the output energy to obtain a simplified energy expression; The simplified energy expression is used as the final output energy expression.

6. The method according to claim 3, characterized in that For a step-down DC-DC converter, the simplified expression for energy is: For a boost DC-DC converter, the simplified expression for energy is: For a buck-boost DC-DC converter, the simplified expression for energy is: Among them, E D is the target port output energy, U i is the input voltage, U o is the output voltage, k L is the inductor current slope, I Lmin is the minimum inductor current, L b is the inductor inductance, E S is the target port output energy, t on and t off They are the on-time and off-time of the switch tube respectively.

7. The method according to claim 3, characterized in that For a step-down DC-DC converter, the switch on-time is calculated using the following formula: For a boost DC-DC converter, the switch on time is calculated using the following formula: t on =T s -t off For a buck-boost DC-DC converter, the switch on time is calculated using the following formula: Among them, I Lmin is the minimum inductor current, k L is the inductor current slope, E tar is the target energy, U o is the output voltage, T s is the switching cycle, U i is the input voltage, t on and t off is the on-time and off-time of the switch tube.

8. A periodic energy control device for a DC-DC converter, characterized in that: include: A port screening unit, used to determine a port having a switch state characteristic and close to an output as a target port according to a topological structure of the DC-DC converter; An energy calculation unit, used for calculating the output energy of the target port in a switching cycle according to the voltage and current of the DC-DC converter; A switch tube conduction time calculation unit, used to determine the switch tube conduction time required to achieve the target energy according to the output energy; A control unit is used to control the switch tube of the DC-DC converter according to the conduction time of the switch tube.

9. A periodic energy control system of a DC-DC converter, characterized in that: include: DC-DC converters, acquisition equipment and controllers; The acquisition device is connected to the DC-DC converter and is used to acquire the voltage and current of the DC-DC converter; The controller is connected to the acquisition device and the DC-DC converter, and is used to execute the method according to any one of claims 1 to 7.

10. A computer storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor of a computer device, the method according to any one of claims 1 to 7 is implemented.

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