Converter device for photovoltaic system

Abstract

The utility model provides a converter device used for photovoltaic equipment. The converter device comprises at least one unidirectional DC-DC conversion part, at least one first terminal part, at least one bidirectional DC-DC conversion part, at least one second terminal part and a housing. The at least one bidirectional DC-to-DC conversion part is connected in parallel with the output of the unidirectional DC-to-DC conversion part. The at least one second terminal portion is electrically connected to the at least one bidirectional DC-to-DC conversion portion and the at least one second terminal portion is suitable for being electrically connected to a photovoltaic panel or an energy storage device. The housing covers the at least one unidirectional DC-to-DC conversion portion and the at least one bidirectional DC-to-DC conversion portion and exposes the at least one first terminal portion and the at least one second terminal portion.

Description

Technical Field

[0001] The utility model relates to a current conversion device, in particular to a current conversion device for photovoltaic equipment. Background Art

[0002] Generally, in a solar power generation site, a current converter needs to be set for solar modules. Since solar modules can only output electric energy and cannot receive electric energy, a unidirectional current converter is usually set for solar modules. If it is necessary to set an energy storage device, such as a rechargeable battery, in the power generation site, a bidirectional current converter needs to be purchased additionally at this time. It occupies more space and has a higher cost. Summary of the Utility Model

[0003] The purpose of the utility model is to provide a current conversion device for photovoltaic equipment, which has a smaller volume, a lower cost and a more flexible connection configuration.

[0004] According to the above purpose, the utility model provides a current conversion device for photovoltaic equipment, including:

[0005] At least one unidirectional DC-DC conversion part, at least one first terminal part, at least one bidirectional DC-DC conversion part, at least one second terminal part and a housing. The at least one first terminal part is electrically connected to the at least one unidirectional DC-DC conversion part and the at least one first terminal part is adapted to be electrically connected to a photovoltaic panel. The at least one bidirectional DC-DC conversion part is connected in parallel with the output of the unidirectional DC-DC conversion part. The at least one second terminal part is electrically connected to the at least one bidirectional DC-DC conversion part and the at least one second terminal part is adapted to be electrically connected to a photovoltaic panel or an energy storage device. The housing covers the at least one unidirectional DC-DC conversion part and the at least one bidirectional DC-DC conversion part and exposes the at least one first terminal part and the at least one second terminal part.

[0006] The current conversion device for photovoltaic equipment according to an embodiment of the utility model further includes a DC-AC conversion part, which is electrically connected to the at least one unidirectional DC-DC conversion part and the at least one bidirectional DC-DC conversion part and is used to provide an AC output.

[0007] The current conversion device for photovoltaic equipment according to an embodiment of the utility model further includes a control part, which is used to control the electrical connection between the at least one bidirectional DC-DC conversion part and the photovoltaic panel or the energy storage device.

[0008] The control part of the current conversion device for photovoltaic equipment according to an embodiment of the utility model is further used to control the electrical connection between the at least one unidirectional DC-DC conversion part and the photovoltaic panel.

[0009] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes a first switch unit for switching the electrical connection between the at least one unidirectional DC-DC conversion unit and the photovoltaic panel.

[0010] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes a second switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel or the energy storage device.

[0011] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes at least one third terminal unit electrically connected to the at least one bidirectional DC-DC conversion unit, wherein the at least one third terminal unit is adapted to be electrically connected to the energy storage device, and the at least one second terminal unit is adapted to be electrically connected to the photovoltaic panel.

[0012] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes a control unit for controlling the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel or the electrical connection between the at least one bidirectional DC-DC conversion unit and the energy storage device.

[0013] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes a second switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel.

[0014] The current conversion device for a photovoltaic device according to an embodiment of the present invention further includes a third switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the energy storage device, wherein the second switch unit and the third switch unit are interlocked mutually exclusively.

[0015] The current conversion device for a photovoltaic device according to an embodiment of the present invention, wherein the energy storage device includes a third switch unit and a rechargeable battery pack, and the third switch unit is used for switching the electrical connection between the rechargeable battery pack and the at least one bidirectional DC-DC conversion unit, wherein the second switch unit and the third switch unit are interlocked mutually exclusively.

[0016] Compared with the prior case, the present invention uses a bidirectional DC-DC conversion unit to replace part of the unidirectional DC-DC conversion unit, making the configuration of solar modules and energy storage devices in a solar power generation site more flexible, taking up less space, and having lower costs. Description of the Drawings

[0017] Figure 1 Schematic structural diagram of a current conversion device for a photovoltaic device according to an embodiment of the present invention;

[0018] Figure 2a Schematic structural diagram of a current conversion device for a photovoltaic device according to another embodiment of the present invention;

[0019] Figure 2b Structural schematic diagram of a current conversion device for a photovoltaic device according to another embodiment of the present utility model;

[0020] Figure 3 Circuit diagram of a unidirectional DC-to-DC conversion section according to an embodiment of the present utility model;

[0021] Figure 4 Circuit diagram of a unidirectional DC-to-DC conversion section according to another embodiment of the present utility model;

[0022] Figure 5 Circuit diagram of a bidirectional DC-to-DC conversion section according to an embodiment of the present utility model;

[0023] Figure 6 Circuit diagram of a bidirectional DC-to-DC conversion section according to another embodiment of the present utility model.

[0024]

Symbol Explanation

[0025] 100, 200, 300: Current conversion device

[0026] CMD: Control section

[0027] PV1, PV2, PVn: Photovoltaic panel

[0028] T1: First terminal section

[0029] T2: Second terminal section

[0030] T3: Third terminal section

[0031] S1: First switch section

[0032] S2: Second switch section

[0033] S3: Third switch section

[0034] SDD1, SDD2: Unidirectional DC-to-DC conversion section

[0035] DDD1: Bidirectional DC-to-DC conversion section

[0036] C ap : Capacitor

[0037] DAC: DC-to-AC conversion section

[0038] GD: Power grid

[0039] CS: Housing

[0040] BT: Energy storage device

[0041] CL: Rechargeable battery pack Detailed implementation manners

[0042] It should be understood that the present utility model can have various variations in different aspects, all of which do not depart from the scope of the present utility model, and the descriptions and drawings therein are essentially for illustrative purposes and not for limiting the present utility model. In addition, the present utility model may use repeated reference symbols and / or markings in different embodiments. These repetitions are for the purpose of simplification and clarity and are not used to define the relationship between each embodiment and / or the described external structure. Furthermore, when a component is referred to as "connected to" or "coupled to" another component, it can be directly connected to or coupled to the other component, or there may be intervening components. Although the numerical ranges and parameters of the broad scope of the present utility model are approximate values, the values are stated as precisely as possible in specific examples. Additionally, it can be understood that although terms such as "first", "second", "third", etc. may be used in the claims to describe different components, these components should not be limited by these terms, and in the embodiments, these components described correspondingly are represented by different component symbols.

[0043] Please refer to Figure 1 , Figure 1 which is a schematic structural diagram of a current conversion device for a photovoltaic device according to an embodiment of the present utility model. The present utility model provides a current conversion device 100 for a photovoltaic device, including: at least one single-direction direct current-to-direct current conversion part SDD1, at least one first terminal part T1, at least one bidirectional direct current-to-direct current conversion part DDD1, at least one second terminal part T2, and a housing CS. The at least one first terminal part T1 is electrically connected to the at least one single-direction direct current-to-direct current conversion part SDD1 and the at least one first terminal part T1 is adapted to be electrically connected to a photovoltaic panel PV1. The at least one bidirectional direct current-to-direct current conversion part DDD1 is output-parallel-connected to the single-direction direct current-to-direct current conversion part SDD1. The at least one second terminal part T2 is electrically connected to the at least one bidirectional direct current-to-direct current conversion part DDD1 and the at least one second terminal part T2 is adapted to be electrically connected to a photovoltaic panel PVn or an energy storage device BT. The housing CS covers the at least one single-direction direct current-to-direct current conversion part SDD1 and the at least one bidirectional direct current-to-direct current conversion part DDD1 and exposes the at least one first terminal part T1 and the at least one second terminal part T2.

[0044] Specifically, the output end of the at least one bidirectional direct current-to-direct current conversion part DDD1 is parallel-connected to the output end of the single-direction direct current-to-direct current conversion part SDD1. The input ends of the at least one bidirectional direct current-to-direct current conversion part DDD1 and the single-direction direct current-to-direct current conversion part SDD1 are independent of each other.

[0045] Specifically, the current conversion device 100 may include a plurality of single-direction DC-DC conversion units SDD1, SDD2, or a plurality of bidirectional DC-DC conversion units DDD1, depending on requirements. The second terminal portion T2 may have the same structure as the first terminal portion T1 but different identification features, such as different colors, to indicate that the user can electrically connect the photovoltaic panel PVn or the energy storage device BT to the second terminal portion T2.

[0046] Specifically, the energy storage device BT is, for example, a rechargeable battery, a hydrogen energy storage power generation system composed of a hydrogen production module and a hydrogen fuel cell, etc. The energy storage device BT may include a rechargeable energy storage system using mechanical energy storage, chemical energy storage, electrochemical energy storage, electrical energy storage, or thermal energy storage, which is not limited in the present utility model.

[0047] Specifically, Figure 3 or Figure 4 Shown is an embodiment of the circuit diagram of a single-direction DC-DC conversion unit SDD1. Figure 5 or Figure 6 Shown is an embodiment of the circuit diagram of a bidirectional DC-DC conversion unit DDD1. However, the present utility model is not limited thereto.

[0048] The current conversion device 100 for a photovoltaic device according to an embodiment of the present utility model further includes a DC-AC conversion unit DAC, which is electrically connected to the at least one single-direction DC-DC conversion unit SDD1 and the at least one bidirectional DC-DC conversion unit DDD1 and is used to provide an AC output.

[0049] Specifically, the current conversion device 100 further includes a parallel-connected capacitor C ap etc., and through the DC-AC conversion unit DAC, it is used to convert direct current into alternating current to be provided to the power grid GD.

[0050] The current conversion device 100 for a photovoltaic device according to an embodiment of the present utility model further includes a control unit CMD, which is used to control the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the photovoltaic panel PVn or the energy storage device BT.

[0051] The current conversion device 100 for a photovoltaic device according to an embodiment of the present utility model, the control unit CMD is further used to control the electrical connection between the at least one single-direction DC-DC conversion unit SDD1 and the photovoltaic panel PV1.

[0052] The current conversion device 100 for a photovoltaic device according to an embodiment of the present utility model, the control unit CMD electrically connects the single-direction DC-DC conversion unit SDD1 / SDD2 and the corresponding photovoltaic panel PV1 / PV2 when the photovoltaic panels PV1 to PVn are installed.

[0053] Specifically, the control unit CMD can charge the energy storage device BT by controlling the electrical connection between the at least one single-direction DC-DC conversion unit SDD1 and the photovoltaic panel PV1 and controlling the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the energy storage device BT, or supply alternating current to the power grid GD by the energy storage device BT through the at least one bidirectional DC-DC conversion unit DDD1 and the DC-AC conversion unit DAC.

[0054] The current conversion device 100 for a photovoltaic device according to an embodiment of the present invention further includes a first switch unit S1 for switching the electrical connection between the at least one single-direction DC-DC conversion unit SDD1 and the photovoltaic panel PV1.

[0055] Specifically, the first switch unit S1 can be a power switch or a manual switch. The power switch can be controlled by the control unit CMD. The manual switch is operated by the user. Specifically, the first switch unit S1 is mainly used to protect the current conversion device 100 and cut off the electrical connection with the photovoltaic panel PV1 to avoid harm to personnel during installation or disassembly.

[0056] The current conversion device 100 for a photovoltaic device according to an embodiment of the present invention further includes a second switch unit S2 for switching the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the photovoltaic panel PVn or the energy storage device BT.

[0057] Specifically, the second switch unit S2 can be a power switch or a manual switch. The power switch can be controlled by the control unit CMD. The manual switch is operated by the user. Specifically, when the second terminal unit T2 is electrically connected to the photovoltaic panel PVn, the second switch unit S2 is mainly used to protect the current conversion device 100 and cut off the electrical connection with the photovoltaic panel PVn to avoid harm to personnel during installation or disassembly. When the second terminal unit T2 is electrically connected to the energy storage device BT, the second switch unit S2 is mainly used to switch to supply power from the energy storage device BT to the current conversion device 100 or charge the energy storage device BT by the current conversion device 100.

[0058] Refer to Figure 2a , Figure 2a which is a schematic structural diagram of the current conversion device 200 for a photovoltaic device according to another embodiment of the present invention. The current conversion device 200 for a photovoltaic device according to an embodiment of the present invention further includes at least one third terminal unit T3 electrically connected to the at least one bidirectional DC-DC conversion unit DDD1, wherein the at least one third terminal unit T3 is adapted to be electrically connected to the energy storage device BT, and the at least one second terminal unit T2 is adapted to be electrically connected to the photovoltaic panel PVn.

[0059] Specifically, in order to prevent the user from incorrectly connecting the energy storage device BT or the photovoltaic panel PVn, the at least one third terminal portion T3 may have a different shape, structure, or color from the at least one second terminal portion T2.

[0060] The current conversion device 200 for a photovoltaic device according to an embodiment of the present invention further includes a control unit CMD for controlling the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the photovoltaic panel PVn or between the at least one bidirectional DC-DC conversion unit DDD1 and the energy storage device BT.

[0061] Specifically, when at least one third terminal portion T3 is electrically connected to the energy storage device BT and at least one second terminal portion T2 is electrically connected to the photovoltaic panel PVn, since both at least one third terminal portion T3 and at least one second terminal portion T2 are electrically connected to the at least one bidirectional DC-DC conversion unit DDD1, it is necessary to control such that only one of the energy storage device BT and the photovoltaic panel PVn can be electrically connected to the at least one bidirectional DC-DC conversion unit DDD1 to avoid the situation where the energy storage device BT supplies power to the photovoltaic panel PVn. Or when the user wants to charge the energy storage device BT through the at least one bidirectional DC-DC conversion unit DDD1, the situation where power is mis-supplied to the photovoltaic panel PVn.

[0062] The current conversion device 200 for a photovoltaic device according to an embodiment of the present invention further includes a second switch unit S2 for switching the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the photovoltaic panel PVn.

[0063] The current conversion device 200 for a photovoltaic device according to an embodiment of the present invention further includes a third switch unit S3 for switching the electrical connection between the at least one bidirectional DC-DC conversion unit DDD1 and the energy storage device BT, wherein the second switch unit S2 and the third switch unit S3 are linked in a mutually exclusive manner.

[0064] Refer to Figure 2b , Figure 2b FIG. is a schematic structural diagram of a current conversion device 300 for a photovoltaic device according to another embodiment of the present invention. The current conversion device 300 for a photovoltaic device according to an embodiment of the present invention, wherein the energy storage device BT includes a third switch unit S3 and a rechargeable battery pack CL, and the third switch unit S3 is used to switch the electrical connection between the rechargeable battery pack CL and the at least one bidirectional DC-DC conversion unit DDD1, wherein the second switch unit S2 and the third switch unit S3 are linked in a mutually exclusive manner.

[0065] Specifically, the second switch unit S2 or the third switch unit S3 can be a power switch or a manual switch. The power switch can be controlled by the control unit CMD. The manual switch is operated by the user. Among them, in order to avoid the situation that the energy storage device BT supplies power to the photovoltaic panel PVn, the second switch unit S2 and the third switch unit S3 are interlocked mutually exclusively. That is, when the second switch unit S2 is connected (on), the third switch unit S3 is disconnected (off), and when the second switch unit S2 is disconnected (off), the third switch unit S3 is connected (on).

[0066] Compared with the previous case, the present utility model uses a bidirectional DC-DC conversion unit to replace part of the unidirectional DC-DC conversion unit, making the configuration of the solar modules and the energy storage device in the solar power generation site more flexible, taking up less space, and having a lower cost.

[0067] The present utility model can be modified by those skilled in the art in various ways, but all modifications shall not exceed the scope protected by the appended claims.

Claims

1. A current conversion device for photovoltaic equipment, characterized in that: include: At least one unidirectional DC-to-DC converter; At least one first terminal portion is electrically connected to the at least one unidirectional DC-DC converter portion and the at least one first terminal portion is suitable for being electrically connected to a photovoltaic panel; At least one bidirectional DC-DC converter is connected in parallel with the output of the unidirectional DC-DC converter; At least one second terminal portion is electrically connected to the at least one bidirectional DC-DC converter portion and the at least one second terminal portion is suitable for being electrically connected to a photovoltaic panel or an energy storage device; and A shell covers the at least one unidirectional DC-DC conversion unit and the at least one bidirectional DC-DC conversion unit and exposes the at least one first terminal unit and the at least one second terminal unit.

2. The current conversion device for photovoltaic equipment according to claim 1, characterized in that: It also includes a DC to AC conversion unit electrically connected to the at least one unidirectional DC to DC conversion unit and the at least one bidirectional DC to DC conversion unit and used to provide an AC output.

3. The current conversion device for photovoltaic equipment according to claim 1, characterized in that: It also includes a control unit for controlling the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel or the energy storage device.

4. The current conversion device for photovoltaic equipment according to claim 3, characterized in that: The control unit is also used to control the electrical connection between the at least one unidirectional DC-DC conversion unit and the photovoltaic panel.

5. The current conversion device for photovoltaic equipment according to claim 4, characterized in that: The invention also includes a first switch unit for switching the electrical connection between the at least one unidirectional DC-DC conversion unit and the photovoltaic panel.

6. The current conversion device for photovoltaic equipment according to claim 3, characterized in that: It also includes a second switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel or the energy storage device.

7. The current conversion device for photovoltaic equipment according to claim 1, characterized in that: It also includes at least one third terminal portion electrically connected to the at least one bidirectional DC-DC conversion portion, wherein the at least one third terminal portion is suitable for being electrically connected to the energy storage device, and the at least one second terminal portion is suitable for being electrically connected to the photovoltaic panel.

8. The current conversion device for photovoltaic equipment according to claim 7, characterized in that: It also includes a control unit for controlling the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel or the at least one bidirectional DC-DC conversion unit and the energy storage device.

9. The current conversion device for photovoltaic equipment according to claim 7, characterized in that: The invention also includes a second switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the photovoltaic panel.

10. The current conversion device for photovoltaic equipment according to claim 9, characterized in that: It also includes a third switch unit for switching the electrical connection between the at least one bidirectional DC-DC conversion unit and the energy storage device, wherein the second switch unit and the third switch unit are mutually exclusive.

11. The current conversion device for photovoltaic equipment according to claim 9, characterized in that: The energy storage device includes a third switch unit and a rechargeable battery pack, wherein the third switch unit is used to switch the electrical connection between the rechargeable battery pack and the at least one bidirectional DC-DC conversion unit, wherein the second switch unit and the third switch unit are mutually exclusive.

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