Three-port high-gain direct-current converter

Abstract

The utility model provides a three-port high-gain direct-current converter which is characterized in that an input power supply Vin is sequentially connected with a capacitor C1, an inductor L2, a capacitor C2, a capacitor C3 and a diode D2 from an anode to a cathode; the first branch comprises a diode D3, a diode D4, a switching tube S1 and a switching tube S3 which are connected in sequence; one end of the inductor L1 is connected to the positive electrode of the input source, and the other end is connected between the capacitor C2 and the capacitor C3; the second branch comprises a switching tube S2 and a diode D1 which are connected in sequence; the positive electrode of the energy storage element is connected between the switch tube S1 and the switch tube S3, and the negative electrode of the energy storage element is connected between the switch tube S2 and the diode D1; and two ends of a branch formed by the capacitor C2 and the capacitor C3 are connected with a load R in parallel. The circuit has high voltage gain, has no voltage constraint, and simplifies the control difficulty of the system.

Description

Technical Field

[0001] The utility model mainly relates to the technical field of converters, in particular to a three-port high-gain DC converter. Background Art

[0002] A typical independent power generation system with energy storage is composed of a unidirectional DC / DC converter and a bidirectional DC / DC converter. The converter is decentralized, large in size and weight, and has multiple power conversion stages, resulting in low efficiency. The three-port DC converter is a new type of converter proposed with the development of new energy power generation technology. Through one converter, the input power V in , battery and load power management and control, with the advantages of high integration, high efficiency, high reliability and low volume cost.

[0003] At the same time, since the port voltage of renewable energy such as photovoltaics and fuel cells, and energy storage components such as lithium batteries and supercapacitors is usually 20V to 60V, the converter is often required to have a higher voltage gain. The traditional Boost converter has limited voltage gain. The Boost-Zeta converter based on topological combination can provide higher voltage gain.

[0004] From the perspective of port voltage constraints, many existing three-port DC converters have strict port voltage constraints between the energy storage port and the input port, and between the energy storage port and the output port. There is no voltage constraint between the energy storage port and the input and output of the Boost-Zeta TPC, thus ensuring that the system has a wider operating range, which is very suitable for occasions such as new energy and energy storage where the port voltage has a wide range of variation depending on environmental conditions and state of charge. From the perspective of port current characteristics, for photovoltaic ports, continuous current ripple helps to optimize and improve the efficiency of renewable energy. For energy storage ports, continuous current ripple helps to extend the service life of the battery.

[0005] The essential task of power electronics is to complete the energy flow between two power ports, that is, to build an orderly energy flow between two power ports. Therefore, a complete power flow contains two basic elements: the energy transmission path and the control applied on the path. The three-port DC converter has three controllable power transmission paths, corresponding to three control quantities (three degrees of freedom). Utility Model Content

[0006] The technical problem to be solved by the utility model is to provide a three-port high-gain DC converter, which has a higher voltage gain, has no voltage constraint, and simplifies the control difficulty of the system.

[0007] In order to solve the above technical problems, the utility model provides a three-port high-gain DC converter, including: an input power supply Vin Capacitor C1, inductor L2, capacitor C2, capacitor C3, and diode D2 are connected in sequence from the positive electrode to the negative electrode, wherein the negative electrode of the diode D2 is connected to the input power supply V in The first branch includes a diode D3, a diode D4, a switch tube S1 and a switch tube S3 connected in sequence, wherein the cathode of the diode D3 is connected between the capacitor C1 and the inductor L2, the anode of the diode D4 is connected to the anode of the diode D3, and the input end or the output end of the switch tube S3 is connected to the input power supply V in The negative electrode of the inductor L1, one end of which is connected to the input power supply V in The positive electrode of the second branch is connected between the capacitor C2 and the capacitor C3, and the other end is connected between the capacitor C2 and the capacitor C3; the second branch includes a switch tube S2 and a diode D1 connected in sequence, wherein the input end or the output end of the switch tube S2 is connected between the capacitor C2 and the capacitor C3, and the cathode of the diode D1 is connected to the input power supply V in a negative electrode of the energy storage element, wherein the positive electrode of the energy storage element is connected between the switch tube S1 and the switch tube S3, and the negative electrode of the energy storage element is connected between the switch tube S2 and the diode D1; a load R is connected in parallel at both ends of the branch composed of the capacitor C2 and the capacitor C3.

[0008] Furthermore, the switch tube is an insulated gate bipolar transistor, a metal oxide semiconductor field effect transistor or a bipolar transistor.

[0009] Furthermore, the three-port high-gain DC converter is in a first working mode, including the switch tube S1 and the switch tube S3 being turned on, the switch tube S2 being turned off, the diode D4 being turned on, and the diode D1, the diode D2 and the diode D3 being turned off.

[0010] Furthermore, the three-port high-gain DC converter is in a second working mode, including the switch tube S1 being turned on, the switch tube S2 and the switch tube S3 being turned off, the diode D1 and the diode D4 being turned on, and the diode D2 and the diode D3 being turned off.

[0011] Furthermore, the three-port high-gain DC converter is in a third working mode, including the switch tube S1, the switch tube S2 and the switch tube S3 being turned off, the diode D1 and the diode D4 being cut off, and the diode D2 and the diode D3 being turned on.

[0012] Furthermore, the three-port high-gain DC converter is in a fourth working mode, including the switch tube S1 being turned off, the switch tube S2 and the switch tube S3 being turned on, and the diode D1, the diode D2, the diode D3 and the diode D4 being turned off.

[0013] Compared with the prior art, the utility model has the following beneficial effects: higher voltage gain, no voltage constraint, more flexible application, continuous current at both the photovoltaic port and the energy storage port, only two degrees of freedom are needed to control the entire three-port system, simplifying the control difficulty of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The accompanying drawings are included to provide a further understanding of the present invention. They are included and constitute a part of the present invention. The accompanying drawings illustrate embodiments of the present invention and together with the specification serve to explain the principles of the present invention. In the accompanying drawings:

[0015] Figure 1 It is a structural schematic diagram of a three-port high-gain DC converter according to an embodiment of the utility model;

[0016] Figure 2 This is the working mode 1 of the three-port high-gain DC converter of the first embodiment of the utility model;

[0017] Figure 3 This is the working mode 2 of the three-port high-gain DC converter of the first embodiment of the utility model;

[0018] Figure 4 This is the working mode three of the three-port high-gain DC converter of the first embodiment of the utility model;

[0019] Figure 5 This is the working mode 4 of the three-port high-gain DC converter of the first embodiment of the utility model;

[0020] Figure 6 It is a schematic diagram of a SIDO control waveform in an embodiment of the utility model;

[0021] Figure 7 It is a schematic diagram of a DISO control waveform in an embodiment of the utility model. DETAILED DESCRIPTION

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the following is a brief introduction to the drawings required for the description of the embodiments. Obviously, the drawings described below are only some examples or embodiments of the present utility model. For ordinary technicians in this field, the present utility model can also be applied to other similar scenarios based on these drawings without creative work. Unless it is obvious from the language environment or otherwise explained, the same reference numerals in the figures represent the same structure or operation.

[0023] It should be understood that when a component is referred to as being "on another component," "connected to another component," "coupled to another component," or "contacting another component," it may be directly on, connected to, coupled to, or contacting the other component, or there may be intervening components. In contrast, when a component is referred to as being "directly on another component," "directly connected to," "directly coupled to," or "directly contacting" another component, there are no intervening components. Similarly, when a first component is referred to as being "electrically in contact with" or "electrically coupled to" a second component, there is an electrical path between the first component and the second component that allows current to flow. The electrical path may include capacitors, coupled inductors, and / or other components that allow current to flow, even without direct contact between conductive components.

[0024] refer to Figure 1 As shown, the three-port high-gain DC converter (Boost-Zeta) provided in this embodiment includes:

[0025] Input power V in From the positive pole to the negative pole, capacitor C1, inductor L2, capacitor C2, capacitor C3, and diode D2 are connected in sequence, where the negative pole of diode D2 is connected to the input power supply V in The first branch includes a diode D3, a diode D4, a switch tube S1 and a switch tube S3 connected in sequence, wherein the cathode of the diode D3 is connected between the capacitor C1 and the inductor L2, the anode of the diode D4 is connected to the anode of the diode D3, and the input end or the output end of the switch tube S3 is connected to the input power supply V in The negative pole of the inductor L1, one end of the inductor L1 is connected to the input power supply V in The positive electrode of the second branch is connected between the capacitor C2 and the capacitor C3, and the other end is connected between the capacitor C2 and the capacitor C3; the second branch includes a switch tube S2 and a diode D1 connected in sequence, wherein the input end or the output end of the switch tube S2 is connected between the capacitor C2 and the capacitor C3, and the cathode of the diode D1 is connected to the input power supply V inThe negative electrode of the energy storage element; the positive electrode of the energy storage element is connected between the switch tube S1 and the switch tube S3, and the negative electrode of the energy storage element is connected between the switch tube S2 and the diode D1; the load R is connected in parallel at both ends of the branch composed of the capacitor C2 and the capacitor C3.

[0026] In some implementations, the switch tube is an insulated gate bipolar transistor, a metal oxide semiconductor field effect transistor or a bipolar transistor.

[0027] The three-port high-gain DC converter of this embodiment is configured as follows according to the on and off conditions of the switch tube and the diode. Figure 2 , Figure 3 , Figure 4 , Figure 5 The modes shown. The modes of the three-port DC converter in different working modes can be composed of three of the following four modes. Specifically,

[0028] The three-port high-gain DC converter is in the first working mode, including the switch tube S1 and the switch tube S3 are turned on, the switch tube S2 is turned off, the diode D4 is turned on, and the diodes D1, D2 and D3 are turned off. The input current i1 charges the inductor L1, and the input power supply V in Together with capacitor C1, it charges inductor L2 and capacitor C2. Capacitor C2 and capacitor C3 together supply power to load R.

[0029] The three-port high-gain DC converter is in the second working mode, including the switch tube S1 is turned on, the switch tubes S2 and S3 are turned off, the diodes D1 and D4 are turned on, and the diodes D2 and D3 are turned off. The input current i1 flows to the inductor L1 and the energy storage battery V bat Charging, input power V in , capacitor C1 and inductor L2 together to capacitor C2 and energy storage battery V bat The capacitors C2 and C3 are charged to supply power to the load R.

[0030] The three-port high-gain DC converter is in the third working mode, including the switch tube S1, the switch tube S2 and the switch tube S3 are turned off, the diode D1 and the diode D4 are turned off, and the diode D2 and the diode D3 are turned on. The input current i1 charges the inductor L1 and the capacitor C1, the inductor L1 charges the capacitor C1, and the inductor L2 charges the capacitor C2. The capacitor C2 and the capacitor C3 together supply power to the load R.

[0031] The three-port high-gain DC converter is in the fourth working mode, including the switch tube S1 is turned off, the switch tubes S2 and S3 are turned on, and the diodes D1, D2, D3 and D4 are turned off. in And energy storage battery V bat To charge the inductor L1, input power V inAnd energy storage battery V bat , capacitor C1 charges inductor L2 and capacitor C2, and capacitor C2 and capacitor C3 together supply power to the load.

[0032] Among them, the SIDO (single input dual output) working mode includes a first working mode, a second working mode and a third working mode; the DISO (dual input single output) working mode includes a first working mode, a third working mode and a fourth working mode.

[0033] from Figure 6 and Figure 7 It can be seen that the control waveforms S1 and S3 of the three-port high-gain DC converter are in a dual relationship, and S2 has a certain logical relationship with S1 and S3, that is, only two degrees of freedom are needed to control the entire three-port system, which simplifies the control difficulty of the system.

[0034] The three-port high-gain DC converter provided in this embodiment has a higher voltage gain, no voltage constraint, and is more flexible in application. The currents of the photovoltaic port and the energy storage port are both continuous. Only two degrees of freedom are required to control the entire three-port system, simplifying the control difficulty of the system.

[0035] For those skilled in the art, the above utility model disclosure is only used as an example and does not constitute a limitation of the utility model. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements and amendments to the utility model. Such modifications, improvements and amendments are suggested in the utility model, so such modifications, improvements and amendments still belong to the spirit and scope of the exemplary embodiments of the utility model.

[0036] Although the present invention has been described with reference to the current specific embodiments, ordinary technicians in this technical field should recognize that the above embodiments are only used to illustrate the present invention, and various equivalent changes or substitutions may be made without departing from the spirit of the present invention. Therefore, as long as the changes and modifications to the above embodiments are within the scope of the essential spirit of the present invention, they will fall within the scope of the claims of the present invention.

Claims

1. A three-port high-gain DC converter, characterized in that: include: Input power V in Capacitor C1, inductor L2, capacitor C2, capacitor C3, and diode D2 are connected in sequence from the positive electrode to the negative electrode, wherein the negative electrode of the diode D2 is connected to the input power supply V in The negative electrode; The first branch includes a diode D3, a diode D4, a switch tube S1 and a switch tube S3 connected in sequence, wherein the cathode of the diode D3 is connected between the capacitor C1 and the inductor L2, the anode of the diode D4 is connected to the anode of the diode D3, and the input end or the output end of the switch tube S3 is connected to the input power supply V in The negative electrode; Inductor L1, one end of which is connected to the input power supply V in The positive electrode of the capacitor C2 and the capacitor C3 have the other end connected between them; The second branch includes a switch tube S2 and a diode D1 connected in sequence, wherein the input end or the output end of the switch tube S2 is connected between the capacitor C2 and the capacitor C3, and the cathode of the diode D1 is connected to the input power supply V in The negative electrode; An energy storage element, wherein the positive electrode of the energy storage element is connected between the switch tube S1 and the switch tube S3, and the negative electrode of the energy storage element is connected between the switch tube S2 and the diode D1; A load R is connected in parallel at both ends of the branch formed by the capacitor C2 and the capacitor C3.

2. The three-port high-gain DC converter according to claim 1, characterized in that: The switch tube is an insulated gate bipolar transistor, a metal oxide semiconductor field effect transistor or a bipolar transistor.

3. The three-port high-gain DC converter according to claim 1, characterized in that: The three-port high-gain DC converter is in a first working mode, including the switch tube S1 and the switch tube S3 being turned on, the switch tube S2 being turned off, the diode D4 being turned on, and the diode D1, the diode D2 and the diode D3 being turned off.

4. The three-port high-gain DC converter according to claim 1, characterized in that: The three-port high-gain DC converter is in the second working mode, including the switch tube S1 being turned on, the switch tube S2 and the switch tube S3 being turned off, the diode D1 and the diode D4 being turned on, and the diode D2 and the diode D3 being turned off.

5. The three-port high-gain DC converter according to claim 1, characterized in that: The three-port high-gain DC converter is in a third working mode, including the switch tube S1, the switch tube S2 and the switch tube S3 being turned off, the diode D1 and the diode D4 being turned off, and the diode D2 and the diode D3 being turned on.

6. The three-port high-gain DC converter according to claim 1, characterized in that: The three-port high-gain DC converter is in a fourth working mode, including the switch tube S1 being turned off, the switch tube S2 and the switch tube S3 being turned on, and the diode D1, the diode D2, the diode D3 and the diode D4 being turned off.

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