Direct-current voltage converter connected with multi-input power supply and control method of direct-current voltage converter

Abstract

The invention discloses a direct-current voltage converter connected with a multi-input power supply and a control method of the direct-current voltage converter, and solves the problems that a converter circuit board in the prior art is complex in structure, large in required circuit board area and the like. The DC voltage converter comprises a plurality of input branches, wherein each input branch comprises an input power supply and a controllable input switch unit; the controllable input switch unit is connected with the positive electrode end of the input power supply and the inductor; the negative electrode ends of the plurality of input power supplies are connected with the input common ground end; the controllable input common-ground switch unit is respectively connected with the input common-ground end and the inductor; each output branch comprises a controllable output switch unit, an output positive electrode end and an output negative electrode end, and the controllable output switch unit is connected with the output positive electrode end and the inductor; an output common ground end, wherein each output negative electrode end is connected with the output common ground end; and the controllable output common-ground switch unit is connected with the output common-ground end and the inductor.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of power electronics, and in particular relates to a DC voltage converter connected to multiple input power supplies and a control method thereof. BACKGROUND

[0002] With the development of new energy technology and the increasing demand for energy saving and consumption reduction, more and more household appliances, electronic products and the like are powered by multiple input power supplies including new energy. Generally, each input power supply needs to be converted into a DC voltage required by a load by a DC voltage converter (DC-DC converter) to meet the demand for working voltage of the same load under different working conditions and / or different loads.

[0003] In the related art, one DC voltage converter is connected to each input power supply, and the DC voltage required by the load is output by controlling the DC voltage converter of the input power supply actually supplying power at present. Each input power supply is provided with a DC voltage converter, which leads to a complex circuit board structure and a large circuit board area in products with multiple input power supplies, thereby increasing the circuit cost and limiting the application of the DC voltage converter in miniaturized and portable products. Moreover, electromagnetic interference is easily generated between multiple DC voltage converters, which affects the output accuracy of the DC voltage converter and further affects the stability of the load, thereby limiting the application range of the DC voltage converter structure in products using multiple input power supplies. SUMMARY

[0004] One of the purposes of the present application is to provide a DC voltage converter connected to multiple input power supplies, which can simultaneously connect to multiple input power supplies and solve at least one of the above technical problems existing in the prior art that multiple input power supplies need to be connected to multiple DC voltage converters.

[0005] To achieve the above-mentioned purposes, the present application adopts the following technical solutions: A DC voltage converter connected to multiple input power supplies, comprising: a plurality of input branches, each of the input branches comprising an input power supply and a controllable input switch unit, a first end of the controllable input switch unit being connected to a positive terminal of the input power supply in the input branch where the controllable input switch unit is located; an inductor, a second end of the controllable input switch unit in each of the input branches being connected to a first end of the inductor; an input common ground terminal, a negative terminal of the input power supply in each of the input branches being connected to the input common ground terminal; a controllable input common ground switch unit, a first end of the controllable input common ground switch unit being connected to the input common ground terminal, and a second end of the controllable input common ground switch unit being connected to the first end of the inductor; a plurality of output branches, each of the output branches comprising a controllable output switch unit, an output positive terminal and an output negative terminal, a first end of the controllable output switch unit being connected with the output positive terminal in the output branch where the controllable output switch unit is located, and a second end of the controllable output switch unit being connected with a second end of the inductor; an output common ground terminal, the output negative terminal in each of the output branches being connected with the output common ground terminal; a controllable output common ground switch unit, a first end of the controllable output common ground switch unit being connected with the output common ground terminal, and a second end of the controllable output common ground switch unit being connected with the second end of the inductor.

[0006] In some embodiments of the present application, the input branches are two, and the input power supplies in the two input branches are respectively a photovoltaic module power supply unit and an energy storage module power supply unit.

[0007] In some embodiments of the present application, the controllable input switch unit, the controllable input common ground switch unit, the controllable output switch unit and the controllable output common ground switch unit are IGBT power switch units or MOSFET power switch units.

[0008] Another object of the present application is to provide a control method of a direct current voltage converter connected with multiple input power supplies, to control the switch units of the direct current voltage converter capable of being connected with multiple input power supplies at the same time, and to realize direct current voltage conversion in various modes by using the direct current voltage converter.

[0009] To achieve the above-mentioned objects, the present application adopts the following technical solutions: A control method of a direct current voltage converter connected with multiple input power supplies, the direct current voltage converter comprising: a plurality of input branches, each of the input branches comprising an input power supply and a controllable input switch unit, a first end of the controllable input switch unit being connected with a positive terminal of the input power supply in the input branch where the controllable input switch unit is located; an inductor, a second end of the controllable input switch unit in each of the input branches being connected with a first end of the inductor; an input common ground terminal, a negative terminal of the input power supply in each of the input branches being connected with the input common ground terminal; a controllable input common ground switch unit, a first end of the controllable input common ground switch unit being connected with the input common ground terminal, and a second end of the controllable input common ground switch unit being connected with the first end of the inductor. a plurality of output branches, each of the output branches comprising a controllable output switch unit, an output positive terminal and an output negative terminal, a first end of the controllable output switch unit being connected with the output positive terminal in the output branch where the controllable output switch unit is located, and a second end of the controllable output switch unit being connected with a second end of the inductor; an output common ground terminal, the output negative terminal in each of the output branches being connected to the output common ground terminal; a controllable output common ground switch unit, a first end of the controllable output common ground switch unit being connected to the output common ground terminal, and a second end of the controllable output common ground switch unit being connected to the second end of the inductor; The control method comprises: acquiring a real-time input-output mode, determining a selected input branch and a selected output branch corresponding to the real-time input-output mode, and controlling controllable input switch units in non-selected input branches and controllable output switch units in non-selected output branches to be in an open state; acquiring a real-time voltage control mode, and controlling switch states of the controllable input switch units in the selected input branch, the controllable output switch units in the selected output branch, the controllable input common ground switch unit, and the controllable output common ground switch unit according to the real-time voltage control mode; the real-time voltage control mode comprises a boost control mode and a buck control mode.

[0010] In some embodiments of the present application, the control method further comprises: when the real-time voltage control mode is the boost control mode, acquiring a real-time boost ratio of the real-time voltage control mode, determining a real-time duty cycle of each switch unit to be controlled according to the real-time boost ratio, and controlling a switch state of the corresponding switch unit according to the real-time duty cycle.

[0011] In some embodiments of the present application, the control method further comprises: when the real-time voltage control mode is the buck control mode, acquiring a real-time buck ratio of the real-time voltage control mode, determining a real-time duty cycle of each switch unit to be controlled according to the real-time buck ratio, and controlling a switch state of the corresponding switch unit according to the real-time duty cycle.

[0012] In some embodiments of the present application, the input branches are two, and input power supplies in the two input branches are respectively a photovoltaic module power supply unit and an energy storage module power supply unit.

[0013] In some embodiments of the present application, the controllable input switch units, the controllable input common ground switch units, the controllable output switch units, and the controllable output common ground switch units are IGBT power switch units or MOSFET power switch units.

[0014] Still another object of the present application provides a power supply system, which comprises the DC voltage converter connected to multiple input power supplies as described above.

[0015] Another object of the present invention is to provide a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-described control method for a DC-DC converter connected to multiple input power sources.

[0016] Compared with the prior art, the advantages and positive effects of the present invention are: The DC-DC converter topology provided by this invention connects an input power supply and a controllable input switch unit in series to form an input branch, and connects an output positive terminal and a controllable output switch unit in series to form an output branch. The negative terminals of multiple input power supplies are connected to a common input ground, and the negative terminals of several output power supplies are connected to a common output ground. Inductors connect the multiple input branches and several output branches. The common input ground and common output ground are also connected to the inductor via controllable input ground switches and controllable output ground switches, respectively. This topology allows the DC-DC converter to accept multiple input power supplies. By controlling the switching units in the topology, various modes of DC-DC voltage conversion can be achieved. This topology simplifies the structure of DC-DC converters accepting multiple input power supplies by sharing the inductor, common input ground, controllable input ground switches, common output ground, and controllable output ground switches, reducing the number of components and the area occupied by the converter. This not only lowers circuit costs but also facilitates the application of DC-DC converters in miniaturized and portable products.

[0017] Other features and advantages of the present invention will become clearer after reading the detailed embodiments of the invention in conjunction with the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 Topology diagrams of some embodiments of the DC-DC converter with multiple input power sources provided by the present invention; Figure 2 Topology diagrams of other embodiments of the DC-DC converter with multiple input power supply provided by the present invention; Figure 3 for Figure 2 A topology diagram of a DC-DC voltage converter in one input-output mode; Figure 4 for Figure 3 The topology diagram is a schematic diagram of the working principle in a voltage control mode; Figure 5 for Figure 3 The topology diagram shows the working principle in another voltage control mode; Figure 6 for Figure 2 A topology diagram of a DC-DC converter in another input-output mode; Figure 7 for Figure 6 The topology diagram is a schematic diagram of the working principle in a voltage control mode; Figure 8 for Figure 6 The topology diagram shows the working principle in another voltage control mode. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they can be implemented by those skilled in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0022] To address the problems in existing technologies where multiple input power sources are used for power supply, such as the need for multiple DC-DC converters due to each input power source being connected to a separate DC-DC converter, resulting in complex circuit board structures and large required circuit board areas, this invention proposes a DC-DC converter with multiple input power sources and its control method. This simplifies the structure of the DC-DC converter with multiple input power sources, reduces the number of components and the area occupied by the converter, thereby lowering circuit costs and facilitating the application of DC-DC converters in miniaturized and portable products.

[0023] Figure 1 The diagram shows the topology of some embodiments of the DC-DC converter with multiple input power supplies provided by the present invention.

[0024] exist Figure 1 The topology diagram shown indicates that the DC-DC converter includes n input branches, m output branches, an inductor L, and an input ground terminal DC. - and common ground terminal U - Where n is a natural number greater than 1, and m is a natural number greater than or equal to 1. Therefore, a DC-DC converter includes two or more input branches and one or more output branches.

[0025] Each input branch includes an input power supply and a controllable input switch unit. The first terminal of the controllable input switch unit is connected to the positive terminal of the input power supply in its respective input branch, and the second terminal of each controllable input switch unit is connected to the first terminal of an inductor. Specifically... Figure 1 In the first input branch, there are input power supply DC1 and controllable input switch unit K. i1 Controllable input switch unit K i1 The first terminal is connected to the positive terminal of the input power supply DC1. + Connection, controllable input switch unit K i1 The second terminal is connected to the first terminal of inductor L ( Figure 1 The left end of inductor L is connected in the middle; the second input branch includes the input power supply DC2 and the controllable input switch unit K. i2 Controllable input switch unit K i2 The first terminal is connected to the positive terminal of the input power supply DC2. + Connection, controllable input switch unit K i2 The second terminal is connected to the first terminal of inductor L; the nth input branch includes the input power supply DCn and the controllable input switch unit K. in Controllable input switch unit K in The first terminal is connected to the positive terminal of the input power supply DCn. + Connection, controllable input switch unit K in The second terminal is connected to the first terminal of the inductor L.

[0026] The negative terminal of the input power supply in each input branch is connected to the input ground DC. - Connect, input common ground DC - It also uses a controllable input common ground switch unit K ic Connected to inductor L. Specifically, the controllable input common-ground switch unit K. ic The first terminal shares a common ground with the input terminal DC. - Connection, controllable input common ground switch unit K ic The second terminal is connected to the first terminal of the inductor L.

[0027] Each output branch includes a controllable output switch unit, a positive output terminal, and a negative output terminal. The first terminal of the controllable output switch unit is connected to the positive output terminal of its respective output branch, and the second terminal of the controllable output switch unit is connected to the second terminal of an inductor. Specifically... Figure 1 As shown, the first output branch includes a controllable output switch unit K. o1 Output positive terminal U1 + and output negative extreme ( Figure 1 (Not shown), Controllable output switching unit K o1 The first terminal and the positive output terminal U1 + Connection, controllable output switch unit Ko1 The second terminal and the second terminal of inductor L ( Figure 1 The middle part is the right end of the inductor L; the second output branch includes the controllable output switch unit K. o2 Output positive terminal U2 + and output negative extreme ( Figure 1 (Not shown), Controllable output switching unit K o2 The first terminal and the positive output terminal U2 + Connection, controllable output switch unit K o2 The second terminal is connected to the second terminal of inductor L; the m-th output branch includes a controllable output switch unit K. om Output positive terminal Um + and output negative extreme ( Figure 1 (Not shown), Controllable output switching unit K om The first terminal and the positive output terminal Um + Connection, controllable output switch unit K om The second terminal is connected to the second terminal of inductor L.

[0028] The negative terminal of each output branch is grounded with the output U. - Connect, output common ground terminal U - It also uses a controllable output common ground switch unit K oc Connected to inductor L. Specifically, the controllable output common ground switch unit K. oc The first terminal and the output share a common ground terminal U. - Connection, controllable input common ground switch unit K oc The second terminal is connected to the second terminal of inductor L.

[0029] In this embodiment, the controllable input switch unit, the controllable output switch unit, the controllable input common ground switch unit, and the controllable output common ground switch unit all have a control terminal ( Figure 1 A switching unit (not shown) can be in a closed or open state under the action of a control signal. When the switching unit is in the closed state, the circuit containing the switching unit is in a conducting state that allows current to flow; when the switching unit is in the open state, the circuit containing the switching unit is in an open state that does not allow current to flow. This embodiment does not limit the structure of the controllable input switching unit, controllable output switching unit, controllable input common ground switching unit, and controllable output common ground switching unit. All switching unit structures that can have both closed and open states under the action of a control signal are within the protection scope of this invention.

[0030] Figure 1In the illustrated DC-DC converter topology, an input branch is formed by connecting an input power supply and a controllable input switch unit in series, and an output branch is formed by connecting an output positive terminal and a controllable output switch unit in series. The negative terminals of multiple input power supplies are connected to a common input ground, and the negative terminals of several output power supplies are connected to a common output ground. Inductors connect the multiple input branches and several output branches. The common input ground and common output ground are also connected to inductors via controllable input ground switches and controllable output ground switches, respectively. This DC-DC converter topology can accept multiple input power supplies. By controlling the various controllable switch units in the topology, various modes of DC-DC conversion can be achieved using this converter. In this topology, by sharing an inductor, input ground, controllable input ground switch unit, output ground, and controllable output ground switch unit, a single DC-DC converter can be connected to multiple input power sources without requiring each input power source to be connected to a separate DC-DC converter. This simplifies the structure of DC-DC converters that connect to multiple input power sources, effectively reducing the number of components and the area occupied by the DC-DC converter. This not only lowers circuit costs but also facilitates the application of DC-DC converters in miniaturized and portable products.

[0031] In other embodiments, the controllable input switching unit, controllable input ground switching unit, controllable output switching unit, and controllable output ground switching unit in the DC-DC converter topology are implemented using IGBT power switching units or MOSFET power switching units.

[0032] In other embodiments, to achieve bidirectional transmission in the topology, the DC-DC converter includes multiple input branches and multiple output branches. All controllable switching units in the topology employ a bidirectional conduction structure. When the switching units are turned on in the first direction, the multiple input branches serve as the actual input branches, connecting to multiple input power supplies, and the output branches serve as the actual output branches, outputting the transformed DC voltage. When the switching units are turned on in the second direction, the multiple input branches serve as the actual output branches, outputting the transformed DC voltage, while the multiple output branches serve as the actual input branches, connecting to multiple input power supplies. This bidirectional DC-DC converter topology facilitates the selection of input and output terminals according to the specific product circuit structure during practical applications, improving ease of use. The specific structure of the controllable switching units with bidirectional conduction function can adopt existing technologies, and this embodiment does not limit this.

[0033] Some embodiments of the present invention also provide a control method for a DC-DC converter connected to multiple input power sources, wherein the structure of the DC-DC converter connected to multiple input power sources is as described in the above embodiments. For a DC-DC converter having the structure described in the above embodiments, by controlling each controllable switching unit, various modes of DC-DC voltage conversion can be achieved using the DC-DC converter. The method for controlling it includes: The system acquires the real-time input-output mode, determines the selected input and output branches corresponding to this mode, and keeps the controllable input switches in the non-selected input branches and the controllable output switches in the non-selected output branches in the off state. The input-output mode includes the number of actual inputs, the number of actual outputs, which branches are used as input branches, and which are used as output branches. The input-output mode can be preset or set in real-time as needed. After the input-output mode is determined, the corresponding input and output branches that need to participate in the operation are identified. These input and output branches are defined as selected input and selected output branches, respectively. Input branches other than the selected input branches are considered non-selected input branches, and output branches other than the selected output branches are considered non-selected output branches. Non-selected input and output branches will not participate in the actual DC-DC voltage conversion process; therefore, the controllable input switches in the non-selected input branches and the controllable output switches in the non-selected output branches are kept in the off state.

[0034] It also acquires the real-time voltage control mode, and controls the switching states of the controllable input switch unit in the selected input branch, the controllable output switch unit in the selected output branch, the controllable input ground switch unit, and the controllable output ground switch unit according to the real-time voltage control mode. Based on the switching states of the controlled switch units, it realizes the DC voltage conversion corresponding to the real-time voltage control mode using a DC voltage converter. Among them, the real-time voltage control mode includes boost control mode and buck control mode.

[0035] In some other embodiments, when the real-time voltage control mode is a boost control mode, the real-time boost ratio of the real-time voltage control mode is also obtained; then, the real-time duty cycle of each switch unit to be controlled is determined according to the real-time boost ratio, the switching state of the corresponding switch unit is controlled according to the real-time duty cycle, and the boosted DC voltage that meets the real-time boost ratio requirement is output by the DC voltage converter.

[0036] When the real-time voltage control mode is buck control mode, the real-time buck ratio of the real-time voltage control mode is obtained; then, the real-time duty cycle of each switch unit to be controlled is determined according to the real-time buck ratio, and the switching state of the corresponding switch unit is controlled according to the real-time duty cycle, so as to use the DC voltage converter to output the reduced DC voltage that meets the real-time buck ratio requirement.

[0037] Figure 2 The diagram shows the topology of some other embodiments of the DC-DC converter with multiple input power supplies provided by the present invention.

[0038] like Figure 2 As shown, in this embodiment, the DC voltage converter has six terminals, namely terminals ①, ②, ③, ④, ⑤, and ⑥. Terminals ①, ②, ④, and ⑤ are connected to the positive terminal of the DC voltage, and terminals ③ and ⑥ are common ground terminals connected to the negative terminal of the DC voltage. L is an inductor, and G1, G2, G3, G4, G5, and G6 are all controllable switching units.

[0039] The DC-DC converter of this embodiment can form a converter structure with multiple input-output modes and up to two input branches and two output branches. The conduction direction of the controllable switching unit is such that the current in the circuit flows from left to right. The specific structure of the DC-DC converter is as follows: Terminals ① and ② are terminals for connecting the positive terminals of the input power supply, and are respectively connected to the positive terminal of one input power supply; G1 is a controllable input switching unit, which, together with the input power supply connected to terminal ①, forms the first input branch and is connected to inductor L; G6 is a controllable input switching unit, which, together with the input power supply connected to terminal ②, forms the second input branch and is connected to inductor L. Terminal ③ is the input ground terminal, which is connected to the negative terminal of each input power supply; G2 is a controllable input ground switching unit, which connects terminal ③ to inductor L. Terminals ④ and ⑤ are used to connect to the positive output terminals; G3, as a controllable output switch unit, forms the first output branch with the positive output terminal connected to terminal ④ and is connected to inductor L; G5, as a controllable output switch unit, forms the second output branch with the positive output terminal connected to terminal ⑤ and is connected to inductor L. Terminal ⑥ is the common ground terminal, connected to the negative terminal of each output branch, and connected to inductor L through G4, which is a controllable output common ground switch unit.

[0040] By selecting a bidirectional controllable switching unit, this DC-DC voltage converter can also form a bidirectional converter structure. Specifically, in addition to allowing the current in the circuit to flow from left to right and forming the structure described above, when the controllable switching unit's conduction direction allows the current in the circuit to flow from right to left, the specific structure of the DC-DC voltage converter is as follows: Terminals ④ and ⑤ are terminals connecting to the positive terminals of the input power supply, each connected to the positive terminal of an input power supply; G3, as a controllable input switching unit, forms the first input branch with the input power supply connected to terminal ④ and is connected to inductor L; G5, as a controllable input switching unit, forms the second input branch with the input power supply connected to terminal ⑤ and is connected to inductor L. Terminal ⑥ is the input ground terminal, connected to the negative terminal of each input power supply; G4, as a controllable input ground switching unit, connects terminal ⑥ to inductor L. Terminals ① and ② are used to connect to the positive output terminals. G1, as a controllable output switch unit, forms the first output branch with the positive output terminal connected to terminal ① and is connected to inductor L. G6, as a controllable output switch unit, forms the second output branch with the positive output terminal connected to terminal ② and is connected to inductor L. Terminal ③ is the common ground terminal, connected to the negative terminal of each output branch, and connected to inductor L through G2, which is a controllable output common ground switch unit.

[0041] In some embodiments, the input power sources in the two input branches are a photovoltaic module power supply unit and an energy storage module power supply unit, respectively. By using the photovoltaic module power supply unit as the input power source, solar energy can be converted into electrical energy to power the load, thereby saving energy. By using the energy storage module power supply unit as the input power source, the energy storage module can store excess electrical energy generated by the photovoltaic module. When the electrical energy provided by the photovoltaic module power supply unit cannot meet the load demand, the energy storage module power supply unit can be used to power the load and maintain the operation of the load.

[0042] The following will be based on Figure 2 Using the example of current transmission from left to right, this paper describes in detail the structure and control principle of the input-output mode and voltage control mode of the DC-DC converter. In this embodiment, each controllable switching unit employs an IGBT power switching unit. In other embodiments, each controllable switching unit employs a MOSFET power switching unit.

[0043] Figure 2 The input-output modes of the DC-DC converter shown include single-input single-output mode, single-input dual-output mode, and dual-input dual-output mode.

[0044] Figure 3 It shows Figure 2The diagram shows the topology of a DC-DC converter in one input-output mode, specifically in single-input-single-output mode. In single-input-single-output mode, terminal ① is selected as the terminal connecting the positive terminal of the input power supply, and G1, as a controllable input switch unit, forms the input branch with the input power supply connected to terminal ①. This input branch is the selected input branch. Terminal ④ is also selected as the terminal connecting the positive terminal of the output, and G3, as a controllable output switch unit, forms the output branch with the output positive terminal connected to terminal ④. This output branch is the selected output branch. The input branch formed by terminal ② and the controllable output switch unit G6 is a non-selected input branch, and G6 is in the open state. The output branch formed by terminal ⑤ and the controllable output switch unit G5 is a non-selected output branch, and G5 is in the open state. To simplify the circuit structure, Figure 3 The non-selected input branch and non-selected output branch have been removed, as well as components such as diodes connected in parallel with transistors in the IGBT power switching unit.

[0045] In other embodiments, the input branch formed by the input power supply connected to terminal ② can also be selected as the selected input branch, and the output branch formed by terminal ⑤ and the controllable output switch unit G5 can be selected as the selected output branch.

[0046] Figure 3 The single-input single-output DC-DC converter shown can implement at least two voltage control modes, including boost control mode and buck control mode.

[0047] Figure 4 It shows Figure 3 The diagram illustrates the working principle of the topology in boost control mode. The control process of each controllable switching unit in boost control mode is as follows: First, such as Figure 4 As shown in Figure (a), controls G1 and G4 are closed, and controls G2 and G3 are open, so that the input power supply charges the inductor L.

[0048] Then, as Figure 4 As shown in Figure (b), control G4 is open, control G3 is closed, and G1 remains closed. The input voltage provided by the input power supply and the inductor L together provide the output voltage to the positive terminal of the output connected to terminal ④. This output voltage is higher than the input voltage provided by the input power supply, thereby achieving the purpose of boosting the voltage through the DC voltage converter.

[0049] By controlling the switching states of G3 and G4 using the duty cycle determined by the boost ratio, a boosted DC voltage that meets the boost ratio requirement can be obtained.

[0050] Figure 5 It shows Figure 3The diagram illustrates the working principle of the topology in buck control mode. The control process of each controllable switching unit in buck control mode is as follows: First, such as Figure 5 As shown in Figure (a), controls G1 and G3 are closed, and controls G2 and G4 are open. The input power supply voltage is supplied to the positive output terminal connected to terminal ④ through inductor L. Due to the voltage division of inductor L, the output voltage at the positive output terminal is lower than the input voltage supplied by the input power supply, thereby achieving the purpose of stepping down the voltage through the DC-DC voltage converter.

[0051] Then, as Figure 5 As shown in Figure (b), control G1 is open, control G2 is closed, G3 remains closed, and G4 remains open. The output voltage is provided by inductor L to the positive terminal of the output connected to terminal ④, so as to realize the freewheeling current in the circuit.

[0052] By controlling the switching states of G1 and G2 using the duty cycle determined by the buck ratio, a reduced DC voltage that meets the buck ratio requirement can be obtained.

[0053] Figure 6 As shown Figure 2 The diagram shows the topology of a DC-DC converter in a single-input dual-output mode. In this mode, terminal ① is selected as the positive terminal for connecting the input power supply. G1, acting as a controllable input switch unit, forms the selected input branch with the input power supply connected to terminal ①. The input branch formed by terminal ② and the controllable output switch unit G6 is the non-selected input branch, and G6 is in the open state. To simplify the circuit structure, Figure 6 The non-selected input branch was removed, as were components such as the diode connected in parallel with the transistor in the IGBT power switching unit.

[0054] Since dual outputs are required, the output branch formed by the positive output terminal of connection terminal ④ and G3 is designated as the first output branch, and the output branch formed by the positive output terminal of connection terminal ⑤ and G5 is designated as the second output branch. Both the first and second output branches are selected as output branches. Figure 6 In the middle, the load between terminal ④ and the output ground terminal ⑥ is represented by RL1, which is the load powered by the first output branch, and a voltage regulator capacitor C1 is connected in parallel on the load RL1; Figure 6 In the diagram, the load between terminal ⑤ and the output ground terminal ⑥ is represented by RL2, which is a load powered by the second output branch, and a voltage regulator capacitor C2 is connected in parallel on the load RL2.

[0055] In some other embodiments, the input branch formed by the input power supply of the connection terminal ② can also be selected as the selected input branch.

[0056] Figure 6The single-input dual-output DC-DC converter shown can implement at least two voltage control modes, including boost control mode and buck control mode.

[0057] Figure 7 As shown Figure 6 The diagram illustrates the working principle of the topology in boost control mode. The control process of each controllable switching unit in boost control mode is as follows: During the voltage boost process, G2 remains in the off state; only the switching states of G1, G3, G4, and G5 need to be controlled. The entire voltage boost process is divided into two stages: the inductor energy storage stage and the load voltage boost stage.

[0058] First, such as Figure 7 As shown in Figure (a), controls G1 and G4 are closed, and controls G3 and G5 are open. At this time, the input voltage Vdc provided by the input power supply charges the inductor L, and the voltage across the inductor increases.

[0059] Then, as Figure 7 As shown in Figure (b), control G4 is open while G1 remains closed. If control G3 is closed and control G5 remains open, then the Vdc supplied by the input power supply and the inductor together power the load RL1. At this time, the voltage across C1 increases, achieving the purpose of boosting the voltage through the DC-DC converter. For example... Figure 7 As shown in Figure (c), control G4 is open while G1 remains closed. If control G5 is closed and control G3 remains open, the Vdc supplied by the input power supply and the inductor together power the load RL2, increasing the voltage across C2 and achieving the purpose of boosting voltage through the DC-DC converter. By controlling the switching states of G3 and G5 with different duty cycles, the two output branches can each output different voltages. Furthermore, in the boost structure where control G4 is open and G1 remains closed, control G3 and G5 to close simultaneously, so that the Vdc supplied by the input power supply and the inductor simultaneously power both loads RL1 and RL2, achieving synchronous boosting of the two output branches.

[0060] Figure 8 As shown Figure 6 The diagram illustrates the working principle of the topology in buck control mode. The control process of each controllable switching unit in buck control mode is as follows: During the voltage reduction process, G4 remains in the off state; only the switching states of G1, G2, G3, and G5 need to be controlled. The entire voltage reduction process is divided into two stages: the inductor voltage division stage and the inductor freewheeling stage.

[0061] First, such as Figure 8As shown in Figure (a), controls G1 and G3 are closed, and controls G2 and G5 are open. The input voltage Vdc provided by the input power supply powers the load RL1 through inductor L. Due to the voltage division of inductor L, the voltage across C1 is lower than Vdc, thus achieving the purpose of providing a step-down output to the load of the first output branch through the DC-DC voltage converter. It can also be done as follows... Figure 8 As shown in Figure (b), when controls G1 and G5 are closed and controls G2 and G3 are open, the input voltage Vdc provided by the input power supply supplies power to load RL2 through inductor L. Due to the voltage division of inductor L, the voltage across C2 is lower than Vdc, thus achieving the purpose of providing a step-down output to the load of the second output branch through the DC-DC converter. Alternatively, G1, G3, and G5 can be closed simultaneously, and G2 can be opened. The input voltage Vdc provided by the input power supply supplies power to both loads RL1 and RL2 simultaneously through inductor L, achieving simultaneous step-down of both output branches, and ensuring that the output voltages of both output branches are the same. By controlling the switching states of G3 and G5 with different duty cycles, the two output branches can each output different voltages. like Figure 8 As shown in Figure (c), when controls G1 and G5 are open and controls G2 and G3 are closed, the inductor L will provide freewheeling current to the load RL1. Figure 8 As shown in Figure (d), when controls G1 and G3 are open and controls G2 and G5 are closed, the inductor L will provide freewheeling current for load RL2. Alternatively, G1 can be opened and G2, G3, and G5 can all be closed, allowing the inductor L to provide freewheeling current for both loads RL1 and RL2.

[0062] Other embodiments of the present invention also provide a power supply system, which includes a DC-DC converter with access to multiple input power sources as described in the above embodiments, and achieves the same technical effects as the DC-DC converters of the corresponding embodiments.

[0063] Other embodiments of the present invention also provide a computer storage medium storing a computer program. When the computer program is executed by a processor, it implements the control method for a DC-DC converter connected to multiple input power sources described in the above embodiments, and achieves the technical effects of the corresponding embodiments.

[0064] The aforementioned computer storage media can be implemented using any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The computer storage media can be any available storage medium accessible to general-purpose or special-purpose computers.

[0065] In some embodiments, a computer storage medium is coupled to a processor, enabling the processor to read information from and write information to the storage medium. Alternatively, the storage medium can be an integral part of the processor. Both the processor and the storage medium can reside in application-specific integrated circuits (ASICs). Of course, the processor and storage medium can also exist as discrete components in the device.

[0066] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions claimed by the present invention.

Claims

1. A DC-DC converter that connects to multiple input power sources, characterized in that, The DC-DC voltage converter includes: Multiple input branches, each of the input branches including an input power supply and a controllable input switch unit, wherein the first terminal of the controllable input switch unit is connected to the positive terminal of the input power supply in the input branch to which it is located; An inductor, wherein the second terminal of each controllable input switch unit in the input branch is connected to the first terminal of the inductor; The input common ground terminal is connected to the negative terminal of the input power supply in each input branch. A controllable input common ground switch unit, wherein its first terminal is connected to the input common ground terminal, and its second terminal is connected to the first terminal of the inductor; Several output branches, each of the output branches includes a controllable output switch unit, an output positive terminal and an output negative terminal, the first terminal of the controllable output switch unit is connected to the output positive terminal of the output branch in which it is located, and the second terminal of the controllable output switch unit is connected to the second terminal of the inductor; The common ground terminal is provided, and the negative terminal of each output branch is connected to the common ground terminal. A controllable output common ground switch unit, the first terminal of which is connected to the output common ground terminal, and the second terminal of which is connected to the second terminal of the inductor.

2. The DC-DC converter with multiple input power supplies according to claim 1, characterized in that, The input branch has two components, and the input power sources in the two input branches are the photovoltaic module power supply unit and the energy storage module power supply unit, respectively.

3. The DC-DC converter with multiple input power supplies according to claim 1 or 2, characterized in that, The controllable input switch unit, the controllable input common ground switch unit, the controllable output switch unit, and the controllable output common ground switch unit are IGBT power switch units or MOSFET power switch units.

4. A control method for a DC-DC converter connected to multiple input power sources, characterized in that, The DC-DC voltage converter includes: Multiple input branches, each of the input branches including an input power supply and a controllable input switch unit, wherein the first terminal of the controllable input switch unit is connected to the positive terminal of the input power supply in the input branch to which it is located; An inductor, wherein the second terminal of each controllable input switch unit in the input branch is connected to the first terminal of the inductor; The input common ground terminal is connected to the negative terminal of the input power supply in each input branch. A controllable input common ground switch unit, wherein its first terminal is connected to the input common ground terminal, and its second terminal is connected to the first terminal of the inductor; Several output branches, each of the output branches includes a controllable output switch unit, an output positive terminal and an output negative terminal, the first terminal of the controllable output switch unit is connected to the output positive terminal of the output branch in which it is located, and the second terminal of the controllable output switch unit is connected to the second terminal of the inductor; The common ground terminal is provided, and the negative terminal of each output branch is connected to the common ground terminal. A controllable output common ground switch unit, wherein its first terminal is connected to the output common ground terminal, and its second terminal is connected to the second terminal of the inductor; The control method includes: Obtain the real-time input-output mode, determine the selected input branch and selected output branch corresponding to the real-time input-output mode, and control the controllable input switch unit in the non-selected input branch and the controllable output switch unit in the non-selected output branch to be in the off state; The system acquires a real-time voltage control mode and controls the switching states of the controllable input switch unit in the selected input branch, the controllable output switch unit in the selected output branch, the controllable input common ground switch unit, and the controllable output common ground switch unit according to the real-time voltage control mode. The real-time voltage control mode includes a boost control mode and a buck control mode.

5. The control method for a DC-DC converter with multiple input power supplies according to claim 4, characterized in that, The control method further includes: When the real-time voltage control mode is a boost control mode, the real-time boost ratio of the real-time voltage control mode is obtained, the real-time duty cycle of each switching unit to be controlled is determined according to the real-time boost ratio, and the switching state of the corresponding switching unit is controlled according to the real-time duty cycle.

6. The control method for a DC-DC converter with multiple input power supplies according to claim 4, characterized in that, The control method further includes: When the real-time voltage control mode is a buck control mode, the real-time buck ratio of the real-time voltage control mode is obtained, the real-time duty cycle of each switching unit to be controlled is determined according to the real-time buck ratio, and the switching state of the corresponding switching unit is controlled according to the real-time duty cycle.

7. The control method for a DC-DC converter with multiple input power supplies according to any one of claims 4 to 6, characterized in that, The input branch has two components, and the input power sources in the two input branches are the photovoltaic module power supply unit and the energy storage module power supply unit, respectively.

8. The control method for a DC-DC converter with multiple input power supplies according to any one of claims 4 to 6, characterized in that, The controllable input switch unit, the controllable input common ground switch unit, the controllable output switch unit, and the controllable output common ground switch unit are IGBT power switch units or MOSFET power switch units.

9. A power supply system, characterized in that, The power supply system includes a DC-DC converter with access to multiple input power sources as described in any one of claims 1 to 3.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the control method of the DC-DC converter with access to multiple input power sources as described in any one of claims 4 to 7.

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