Photovoltaic converter and photovoltaic system

Abstract

The utility model discloses a photovoltaic converter and a photovoltaic system. The photovoltaic converter comprises a DC-DC module, a first connecting end, a second connecting end and a third connecting end, the DC-DC module is respectively connected with the first connecting end, the second connecting end and the third connecting end, and is used for boosting the photovoltaic voltage accessed by the first connecting end and then outputting the boosted photovoltaic voltage to the second connecting end or the third connecting end; the second connecting end is used for connecting a battery, and the third connecting end is used for connecting a grid-connected inverter. According to the technical scheme of the utility model, a new energy storage system does not need to be installed, low-cost transformation of the grid-connected inverter can be realized, coupling use of the grid-connected inverter and the energy storage battery can be realized, an existing inverter does not need to be transformed into the energy storage inverter, the problem of energy waste caused by mismatching of the energy storage inverter and the photovoltaic assembly is avoided, and the energy storage efficiency is improved. And energy can be saved.

Description

Technical Field

[0001] The utility model relates to the technical field of photovoltaic power generation, in particular to a photovoltaic converter and a photovoltaic system. Background Art

[0002] With the continuous development of society and the rapid advancement of science and technology, energy issues have gradually become a focus of attention. Photovoltaic power generation is currently the most widely used and mature technology. Specifically, photovoltaic modules convert sunlight into direct current (DC) electricity, which is then transmitted to a grid-connected inverter, where it is converted into AC power and fed into the power grid.

[0003] In existing technologies, some scenarios require storing photovoltaic power and discharging it through batteries to power loads at appropriate times. However, in existing photovoltaic systems, grid-connected inverters are not compatible with energy storage devices such as batteries.

[0004] Currently, two approaches are commonly used: installing a new energy storage system or converting an existing grid-connected inverter system into an energy storage inverter. Installing a new energy storage system typically requires dismantling the existing grid-connected system and rewiring, which is time-consuming, expensive, and wasteful. Converting an existing grid-connected inverter system into an energy storage inverter requires matching the inverter with the existing PV panels. Since the power of a single PV panel has increased significantly, installing a new energy storage inverter may result in energy waste. Utility Model Content

[0005] The utility model provides a photovoltaic converter and a photovoltaic system, which can realize the coupled use of a grid-connected inverter and an energy storage battery without installing a new energy storage system, with low cost and energy saving.

[0006] According to one aspect of the present invention, a photovoltaic converter is provided, comprising: a DC-DC module, a first connection terminal, a second connection terminal, and a third connection terminal; the DC-DC module is connected to the first connection terminal, the second connection terminal, and the third connection terminal, respectively, and is configured to boost a photovoltaic voltage connected to the first connection terminal and output the voltage to the second connection terminal or the third connection terminal;

[0007] The second connection end is used to connect to a battery, and the third connection end is used to connect to a grid-connected inverter.

[0008] Optionally, the DC-DC module includes a DC-DC circuit and a control unit, the control unit being connected to the DC-DC circuit; the control unit being configured to control the DC-DC circuit to boost the photovoltaic voltage connected to the first connection terminal to obtain a first boosted voltage according to a first control instruction inputted thereto, and output the first boosted voltage to the second connection terminal;

[0009] Alternatively, the control unit is configured to control the DC-DC circuit to boost the photovoltaic voltage connected to the first connection terminal to obtain a first boosted voltage according to the input second control instruction, and output the first boosted voltage to the third connection terminal;

[0010] or,

[0011] The grid-connected inverter is connected to a useful load; the control unit is used to control the DC-DC circuit to boost the battery voltage connected to the second connection terminal to obtain a second boosted voltage according to the input third control instruction, and output the second boosted voltage to the third connection terminal.

[0012] Optionally, the photovoltaic converter further includes at least one filter module, which is connected between the DC-DC module and the first connection end, between the DC-DC module and the second connection end, or between the DC-DC module and the third connection end.

[0013] Optionally, the DC-DC module includes an input end, an output end, and an input-output end; the input end of the DC-DC module is connected to the first connection end, the output end of the DC-DC module is connected to the third connection end, and the input-output end of the DC-DC module is connected to the second connection end;

[0014] The DC-DC module is used to boost the photovoltaic voltage connected to the input end to obtain the first boosted voltage, and output it to the second connection end through the input and output end;

[0015] Alternatively, the DC-DC module is used to boost the photovoltaic voltage connected to the input end, simulate a photovoltaic curve to match the characteristics of photovoltaic module power generation, obtain the first boosted voltage, and output it to the third connection end through the input and output ends.

[0016] Optionally, the photovoltaic converter further comprises: a DC transformer;

[0017] The input end of the DC transformer is connected to the output end of the DC-DC module, and the output end of the DC transformer is connected to the third connection end. The DC transformer is used to boost the voltage of the output end of the DC-DC module to a third boost voltage and output it to the grid-connected inverter.

[0018] Optionally, the photovoltaic converter further comprises: at least one of a wired communication module, a wireless communication module, a rectifier module, and a display module;

[0019] The wired communication module is connected to the communication terminal of the photovoltaic converter, and the wired communication module is used to connect to the battery or the grid-connected inverter;

[0020] The wireless communication module is used to communicate with the terminal device;

[0021] The rectifier module is connected between the AC interface of the photovoltaic converter and the battery, and is used to rectify the AC power input by the AC interface;

[0022] The display module is connected to the meter interface of the photovoltaic converter, the meter interface is used to connect to the meter, and the display module is used to display the amount of electricity transmitted by the grid-connected inverter to the power grid.

[0023] Optionally, the DC-DC module and the rectifier module are arranged in a first area inside the photovoltaic converter, and the wired communication module and the wireless communication module are arranged in a second area inside the photovoltaic converter, and the first area and the second area are isolated from each other.

[0024] Optionally, the photovoltaic converter further comprises: a housing, wherein the first connection terminal, the third connection terminal, and the AC interface are arranged on a first side of the housing, and the second connection terminal, the communication terminal, and the electric meter interface are arranged on a second side of the housing;

[0025] The first side is opposite to the second side.

[0026] Optionally, the photovoltaic converter further includes an outer mounting bracket and / or a back-mounted plate arranged on the outer side of the housing.

[0027] According to another aspect of the present invention, a photovoltaic system is provided, comprising a photovoltaic module, a battery, a grid-connected inverter, and the photovoltaic converter provided by any one of the above embodiments;

[0028] The photovoltaic converter is connected to the photovoltaic assembly, the battery and the grid-connected inverter respectively.

[0029] The technical solution of the present embodiment of the utility model comprises a DC-DC module, a first connection terminal, a second connection terminal, and a third connection terminal. The first connection terminal allows access to the photovoltaic voltage, so that the DC-DC module can boost the photovoltaic voltage and output it to the battery through the second connection terminal, or to the grid-connected inverter through the third connection terminal. The boosting by the DC-DC module ensures that the photovoltaic voltage matches the battery voltage, improving charging efficiency and battery life. The boosted voltage is output to the grid-connected inverter through the third connection terminal, which then converts the DC power generated by the photovoltaic module into AC power that meets grid standards for integration into the grid. The boosted voltage ensures that the input voltage of the grid-connected inverter is within its operating range, thereby improving the overall efficiency and stability of the system. This configuration eliminates the need to install a new energy storage system, enabling compatibility between the grid-connected inverter and the battery, thereby improving system flexibility and reliability while reducing modification costs. It also eliminates the need to convert existing inverters into energy storage inverters, avoiding energy waste caused by mismatch between the energy storage inverter and the photovoltaic modules, thereby saving energy. It can also enable photovoltaic converters to flexibly adapt to different application requirements, thereby improving the functionality and economic benefits of photovoltaic systems.

[0030] It should be understood that the content described in this section is not intended to identify the key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 A schematic structural diagram of a photovoltaic converter provided by an embodiment of the present utility model;

[0033] Figure 2 A schematic structural diagram of another photovoltaic converter provided by an embodiment of the present utility model;

[0034] Figure 3 A schematic structural diagram of another photovoltaic converter provided by an embodiment of the present utility model;

[0035] Figure 4 A schematic structural diagram of another photovoltaic converter provided by an embodiment of the present utility model;

[0036] Figure 5 A schematic structural diagram of another photovoltaic converter provided by an embodiment of the present utility model;

[0037] Figure 6 A right side view of a photovoltaic converter provided by an embodiment of the present utility model;

[0038] Figure 7 A left side view of a photovoltaic converter provided by an embodiment of the present utility model;

[0039] Figure 8 A top view of a photovoltaic converter provided by an embodiment of the present utility model;

[0040] Figure 9 A schematic structural diagram of a photovoltaic system provided in an embodiment of the present utility model. DETAILED DESCRIPTION

[0041] In order to help those skilled in the art better understand the present invention, the following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts should fall within the scope of protection of the present invention.

[0042] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and their variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0043] Figure 1 A schematic diagram of a photovoltaic converter according to an embodiment of the present invention is provided. Figure 1The photovoltaic converter 100 includes: a DC-DC module 10, a first connection terminal 101, a second connection terminal 102 and a third connection terminal 103; the DC-DC module 10 is connected to the first connection terminal 101, the second connection terminal 102 and the third connection terminal 103 respectively, and is used to boost the photovoltaic voltage connected to the first connection terminal 101 and output it to the second connection terminal 102 or the third connection terminal 103; the second connection terminal 102 is used to connect to a battery, and the third connection terminal 103 is used to connect to a grid-connected inverter.

[0044] The first connection terminal 101 is used to connect to a photovoltaic module, and input the photovoltaic voltage output by the photovoltaic module into the DC-DC module 10. Exemplarily, the first connection terminal 101 can be connected to the photovoltaic module by directly connecting the connection wire that originally connected the photovoltaic module to the grid-connected inverter to the first connection terminal 101. The first connection terminal 101 is compatible with all photovoltaic connection terminals. Then, a new photovoltaic connection wire is added and connected to the photovoltaic input interface position of the grid-connected inverter through the third connection terminal 103. Alternatively, the connection between the original photovoltaic module and the grid-connected inverter is cut, the photovoltaic converter 100 is installed in the middle position, and the two ends of the cut wire are respectively pressed into terminals and connected to the first connection terminal 101 and the third connection terminal 103. The DC-DC module 10 is a device that converts electrical energy of one voltage value into electrical energy of another voltage value in a direct current circuit.

[0045] Specifically, when photovoltaic voltage is input to DC-DC module 10 through first connection terminal 101, DC-DC module 10 boosts the photovoltaic voltage and outputs it to second connection terminal 102 or third connection terminal 103. The voltage is then output to a battery through second connection terminal 102 or to a grid-connected inverter through third connection terminal 103. When output to a battery through second connection terminal 102, the photovoltaic voltage can be used to charge the battery. When output to a grid-connected inverter through third connection terminal 103, the photovoltaic voltage can be used to power household loads or be fed into the grid.

[0046] The technical solution of the present embodiment of the utility model comprises a DC-DC module, a first connection terminal, a second connection terminal, and a third connection terminal. The first connection terminal allows access to the photovoltaic voltage, so that the DC-DC module can boost the photovoltaic voltage and output it to the battery through the second connection terminal, or to the grid-connected inverter through the third connection terminal. The boosting by the DC-DC module ensures that the photovoltaic voltage matches the battery voltage, improving charging efficiency and battery life. The boosted voltage is output to the grid-connected inverter through the third connection terminal, which then converts the DC power generated by the photovoltaic module into AC power that meets grid standards for integration into the grid. The boosted voltage ensures that the input voltage of the grid-connected inverter is within its operating range, thereby improving the overall efficiency and stability of the system. This configuration eliminates the need to install a new energy storage system, enabling compatibility between the grid-connected inverter and the battery, thereby improving system flexibility and reliability while reducing modification costs. It also eliminates the need to convert existing inverters into energy storage inverters, avoiding energy waste caused by mismatch between the energy storage inverter and the photovoltaic modules, thereby saving energy. It can also enable photovoltaic converters to flexibly adapt to different application requirements, thereby improving the functionality and economic benefits of photovoltaic systems.

[0047] Figure 2 This is a schematic diagram of another photovoltaic converter provided by an embodiment of the present invention, referring to Figure 2 Based on the above embodiment, the DC-DC module 10 includes a DC-DC circuit 11 and a control unit 12, and the control unit 12 is connected to the DC-DC circuit 11; the control unit 12 is used to control the DC-DC circuit 11 to boost the photovoltaic voltage connected to the first connection terminal 101 to obtain a first boosted voltage according to an input first control instruction, and output the first boosted voltage to the second connection terminal 102; or, the control unit 12 is used to control the DC-DC circuit 11 to boost the photovoltaic voltage connected to the first connection terminal to obtain a first boosted voltage according to an input second control instruction, and output the first boosted voltage to the third connection terminal 103; or, if the grid-connected inverter is connected to a useful load, the control unit 12 is used to control the DC-DC circuit 11 to boost the battery voltage connected to the second connection terminal 102 to obtain a second boosted voltage according to an input third control instruction, and output the second boosted voltage to the third connection terminal 103.

[0048] The first control instruction, the second control instruction and the third control instruction may be provided by an external device terminal.

[0049] Specifically, when there is sufficient sunlight and there is no need to power the household load, the external terminal device outputs a first control instruction to the control unit 12. After responding to the first control instruction, the control unit 12 controls the output voltage of the DC-DC circuit 11 to be the first boosted voltage, and outputs the first boosted voltage to the second connection terminal 102 for battery charging; when it is necessary to power the household load or to perform grid-connected operation, the external terminal device outputs a second control instruction to the control unit 12. After responding to the second control instruction, the control unit 12 controls the output voltage of the DC-DC circuit 11 to be the first boosted voltage, and outputs the first boosted voltage to the third connection terminal 103, so that the grid-connected inverter can The first boosted voltage is converted into alternating current that meets the grid standard so that the electricity can be integrated into the grid, or the grid-connected inverter converts the first boosted voltage into alternating current with the same power type as the household load so as to supply power to the household load; when the weather conditions are bad and power cannot be supplied by the photovoltaic voltage, and the battery has power, the external terminal device outputs a third control instruction to the control unit 12. After responding to the third control instruction, the control unit 12 controls the output voltage of the DC-DC circuit 11 to be the second boosted voltage, and outputs the second boosted voltage to the third connection terminal 103, and then converts the second boosted voltage into alternating current with the same power type as the household load through the grid-connected inverter so as to supply power to the household load.

[0050] The technical solution of the present invention embodiment, by providing a DC-DC circuit and a control unit, enables the control unit to control different operating modes of the DC-DC circuit according to different control instructions to meet different needs. This improves the efficiency, stability, and flexibility of the photovoltaic system. Furthermore, this configuration enables the system to adapt to a variety of application scenarios, enhancing the overall performance and applicability of the system.

[0051] Figure 3 This is a schematic diagram of another photovoltaic converter provided by an embodiment of the present invention, referring to Figure 3 Based on the above embodiments, the photovoltaic converter 100 further includes at least one filter module, which is connected between the DC-DC module 10 and the first connection terminal 101, between the DC-DC module 10 and the second connection terminal 102, or between the DC-DC module 10 and the third connection terminal 103.

[0052] In which, the photovoltaic converter 100 includes three filter modules as an example. For example, one filter module is connected between the DC-DC module 10 and the first connection terminal 101, and is used to filter the photovoltaic voltage input through the first connection terminal 101; one filter module is connected between the DC-DC module 10 and the second connection terminal 102, and is used to filter the first boost voltage output by the DC-DC module 10 to the second connection terminal 102; and one filter module is connected between the DC-DC module 10 and the third connection terminal 103, and is used to filter the first boost voltage output by the DC-DC module 10 to the third connection terminal 103.

[0053] Specifically, the filter modules are connected to the input and output terminals of the DC-DC module 10, respectively, and are used to filter the input and output voltages of the DC-DC module 10. By providing the filter modules, noise and ripple in the input and output voltages can be reduced, thereby improving power quality and providing more stable power output.

[0054] Optionally, continue to refer to Figure 3 The DC-DC module 10 includes an input terminal 13, an output terminal 14 and an input-output terminal 15; the input terminal 13 of the DC-DC module 10 is connected to the first connection terminal 101, the output terminal 14 of the DC-DC module 10 is connected to the third connection terminal 103, and the input-output terminal 15 of the DC-DC module 10 is connected to the second connection terminal 102; the DC-DC module 10 is used to boost the photovoltaic voltage connected to the input terminal 13 to obtain a first boosted voltage, and output it to the second connection terminal 102 through the input-output terminal 15; or, the DC-DC module 10 is used to boost the photovoltaic voltage connected to the input terminal 13, simulate the photovoltaic curve to match the characteristics of photovoltaic module power generation, obtain the first boosted voltage, and output it to the third connection terminal 103 through the input-output terminal 14.

[0055] Specifically, the input / output terminals 15 of the DC-DC module 10 can be understood as ports that can be used as both input and output terminals. For example, when the input / output terminals 15 of the DC-DC module 10 are used as input terminals, the battery can be charged through these terminals; when the input / output terminals 15 of the DC-DC module 10 are used as output terminals, the battery can be discharged through these terminals. In other words, both charging and discharging of the battery are achieved through the input / output terminals 15 of the DC-DC module 10. For example, the DC-DC module 10 can be an isolated DC-DC converter. An isolated DC-DC converter is a special type of DC-DC converter that features electrical isolation between its input and output. This converter uses a high-frequency transformer to achieve electrical isolation between its input and output, allowing a single port to function as both an input and an output. The simulated photovoltaic curve can be understood as the DC-DC module 10 regulating the photovoltaic voltage output by the photovoltaic module to a voltage range suitable for the grid-connected inverter input, thereby ensuring more stable power quality at the grid-connected inverter input. For example, assume that the PV panel output voltage is 400V, while the grid-connected inverter input voltage range is 450V to 550V. Therefore, the DC-DC module 10 needs to simulate the photovoltaic curve and increase the output voltage of the PV panel to the range of 450V to 550V to ensure that the grid-connected inverter can safely and efficiently convert electrical energy into the grid or power other household loads.

[0056] Specifically, when the battery needs to be charged, the DC-DC module 10 boosts the photovoltaic voltage inputted from the input terminal 13 to obtain a first boosted voltage, and then charges the battery through the input / output terminal 15. When the photovoltaic voltage needs to be used to power household loads or when grid-connected operation is required, the DC-DC module 10 boosts the photovoltaic voltage inputted from the input terminal 13, simulates a photovoltaic curve to match the power generation performance of the photovoltaic module, and obtains a first boosted voltage. The first boosted voltage is then output to the third connection terminal 103 through the output terminal 14. When the battery needs to be discharged, the DC-DC module 10 boosts the battery voltage through the input / output terminal 15, simulates a photovoltaic curve to match the power generation performance of the photovoltaic module, and obtains a second boosted voltage. The second boosted voltage is then output to the third connection terminal 103 through the output terminal 14. This configuration is compatible with the battery's charge and discharge characteristics.

[0057] Figure 4 This is a schematic diagram of another photovoltaic converter provided by an embodiment of the present invention, referring to Figure 4Based on the above embodiments, the photovoltaic converter 100 further includes: a DC transformer 30; the input end of the DC transformer 30 is connected to the output end 14 of the DC-DC module 10, and the output end of the DC transformer 30 is connected to the third connection end 103. The DC transformer 30 is used to boost the voltage of the output end 14 of the DC-DC module 10 to a third boosted voltage and output it to the grid-connected inverter.

[0058] Specifically, the DC transformer 30 is used to adjust the input voltage to match the operating range of the grid-connected inverter. For example, if the first boost voltage output by the DC-DC module 10 is 300V and the second boost voltage is 350V, and the input voltage range of the grid-connected inverter is 450V to 550V, to effectively match the grid-connected inverter, the DC transformer can boost the voltage output by the DC-DC module 10 from 300V or 350V to a voltage suitable for the inverter's input range. This ensures that the grid-connected inverter can operate stably and convert DC power into AC power, allowing it to maintain efficient operation.

[0059] Figure 5 This is a schematic diagram of another photovoltaic converter provided by an embodiment of the present invention, referring to Figure 5 Based on the above embodiments, the photovoltaic converter 100 further includes: at least one of a wired communication module 40, a wireless communication module 50, a rectifier module 60, and a display module 70; the wired communication module 40 is connected to the communication terminal 104 of the photovoltaic converter 100 and is used to connect to a battery or a grid-connected inverter; the wireless communication module 50 is used to communicate with a terminal device; the rectifier module 60 is connected between the AC interface 105 of the photovoltaic converter and the battery and is used to rectify the AC power input by the AC interface 105; the display module 70 is connected to the meter interface 106 of the photovoltaic converter 100 and is used to connect to an electric meter; and the display module 70 is used to display the amount of electricity supplied by the grid-connected inverter to the grid.

[0060] Specifically, when the wired communication module 40 is connected to a grid-connected inverter, it can obtain the parameters of the grid-connected inverter. When the wired communication module 40 is connected to a battery, it can communicate with the battery and obtain relevant battery parameters, such as battery charge, battery voltage, or battery cell temperature. The wireless communication module 50 communicates with a terminal device and can output control instructions through the terminal device to control the operating mode of the DC-DC module 10. When charging the battery via AC power, the AC power is connected to the AC interface 105, and the AC power is rectified by the rectifier module 60 to meet the charging voltage of the battery pack.

[0061] Optionally, continue to refer to Figure 5The DC-DC module 10 and the rectifier module 60 are arranged in the first area inside the photovoltaic converter 100, and the wired communication module 40 and the wireless communication module 50 are arranged in the second area inside the photovoltaic converter. The first area and the second area are isolated from each other.

[0062] It is understood that the DC-DC module 10, rectifier module 60, wired communication module 40, and wireless communication module 50 shown in the figure are all arranged on a circuit board, and corresponding functions are achieved through corresponding circuit structures. The isolation of the first and second regions mentioned above also corresponds to the isolation operation on the circuit board. Exemplarily, the method of isolating the first and second regions includes arranging the circuit structure of the first region and the circuit structure of the second region away from each other; or isolating the first and second regions by providing a protective circuit. By isolating the first and second regions, the low-voltage module can be protected from the influence of high voltage, thereby improving the overall reliability and safety of the system.

[0063] Figure 6 This is a right side view of a photovoltaic converter provided by an embodiment of the present utility model. Figure 7 This is a left view of a photovoltaic converter provided by an embodiment of the present utility model. Figure 8 A top view of a photovoltaic converter provided by an embodiment of the present invention, specifically a three-view structure of the photovoltaic converter provided by any of the above embodiments, with reference to Figure 6-Figure 8 Based on the above embodiments, the photovoltaic converter further includes: a housing 200, a first connection terminal 101, a third connection terminal 103, and an AC interface 105 are arranged on a first side of the housing, and a second connection terminal 102, a communication terminal 104, and an electric meter interface 106 are arranged on a second side of the housing; wherein the first side is opposite to the second side.

[0064] Specifically, by setting the wiring terminal on the outside of the shell 200, different on-site installation conditions can be met. At the same time, the photovoltaic converter also supports forward and reverse installation. When the photovoltaic component input position is on the left, the wiring connection can be installed in the forward direction. When the photovoltaic component is on the right, the device can be rotated 180 degrees for installation to meet the wiring requirements.

[0065] Optionally, the photovoltaic converter further includes an external mounting bracket and / or a back-mounted plate disposed on the housing 200 .

[0066] Specifically, the mounting bracket allows for stacking the photovoltaic converter on the battery pack, or for wall-mounting the photovoltaic converter after securing the backing plate to the wall with expansion bolts, meeting installation requirements in a variety of scenarios.

[0067] Figure 9 A schematic diagram of a photovoltaic system according to an embodiment of the present invention is provided. Figure 9Based on the above embodiments, the photovoltaic system includes a photovoltaic module 300, a battery 500, a grid-connected inverter 400 and a photovoltaic converter 100 provided in any of the above embodiments; the photovoltaic converter 100 is respectively connected to the photovoltaic module 300, the battery 500 and the grid-connected inverter 400.

[0068] Specifically, the photovoltaic module 300 is connected to the photovoltaic converter 100 via a first connection terminal, the battery 500 is connected to the photovoltaic converter 100 via a second connection terminal, and the grid-connected inverter 400 is connected to the photovoltaic converter 100 via a third connection terminal. Therefore, the photovoltaic system also has the beneficial effects of any of the above embodiments.

[0069] It should be understood that the various forms of the processes shown above can be used to reorder, add, or delete steps. For example, the steps described in this utility model can be performed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of this utility model can be achieved. This is not limited herein.

[0070] The above specific embodiments do not limit the scope of protection of this utility model. Those skilled in the art will appreciate that various modifications, combinations, sub-combinations, and substitutions may be made based on design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model shall be included within the scope of protection of this utility model.

Claims

1. A photovoltaic converter, characterized in that: include: a DC-DC module, a first connection terminal, a second connection terminal, and a third connection terminal; the DC-DC module is connected to the first connection terminal, the second connection terminal, and the third connection terminal, respectively, and is used to boost the photovoltaic voltage connected to the first connection terminal and output it to the second connection terminal or the third connection terminal; The second connection end is used to connect to a battery, and the third connection end is used to connect to a grid-connected inverter.

2. The photovoltaic converter according to claim 1, wherein: The DC-DC module includes a DC-DC circuit and a control unit, wherein the control unit is connected to the DC-DC circuit; the control unit is configured to control the DC-DC circuit to boost the photovoltaic voltage connected to the first connection terminal to obtain a first boosted voltage according to a first control instruction input, and output the first boosted voltage to the second connection terminal; Alternatively, the control unit is configured to control the DC-DC circuit to boost the photovoltaic voltage connected to the first connection terminal to obtain a first boosted voltage according to the input second control instruction, and output the first boosted voltage to the third connection terminal; or, The grid-connected inverter is connected to a useful load; the control unit is used to control the DC-DC circuit to boost the battery voltage connected to the second connection terminal to obtain a second boosted voltage according to the input third control instruction, and output the second boosted voltage to the third connection terminal.

3. The photovoltaic converter according to claim 1, wherein: It also includes at least one filter module, which is connected between the DC-DC module and the first connection end, between the DC-DC module and the second connection end, or between the DC-DC module and the third connection end.

4. The photovoltaic converter according to claim 2, characterized in that The DC-DC module includes an input end, an output end, and an input-output end; the input end of the DC-DC module is connected to the first connection end, the output end of the DC-DC module is connected to the third connection end, and the input-output end of the DC-DC module is connected to the second connection end; The DC-DC module is used to boost the photovoltaic voltage connected to the input end to obtain the first boosted voltage, and output it to the second connection end through the input and output end; Alternatively, the DC-DC module is used to boost the photovoltaic voltage connected to the input end, simulate a photovoltaic curve to match the characteristics of photovoltaic module power generation, obtain the first boosted voltage, and output it to the third connection end through the input and output ends.

5. The photovoltaic converter according to claim 1, wherein: Also includes: DC transformer; The input end of the DC transformer is connected to the output end of the DC-DC module, and the output end of the DC transformer is connected to the third connection end. The DC transformer is used to boost the voltage of the output end of the DC-DC module to a third boost voltage and output it to the grid-connected inverter.

6. The photovoltaic converter according to claim 1, wherein: Also includes: At least one of a wired communication module, a wireless communication module, a rectifier module, and a display module; The wired communication module is connected to the communication terminal of the photovoltaic converter, and the wired communication module is used to connect to the battery or the grid-connected inverter; The wireless communication module is used to communicate with the terminal device; The rectifier module is connected between the AC interface of the photovoltaic converter and the battery, and is used to rectify the AC power input by the AC interface; The display module is connected to the meter interface of the photovoltaic converter, the meter interface is used to connect to the meter, and the display module is used to display the amount of electricity transmitted by the grid-connected inverter to the power grid.

7. The photovoltaic converter according to claim 6, characterized in that The DC-DC module and the rectifier module are arranged in a first area inside the photovoltaic converter, and the wired communication module and the wireless communication module are arranged in a second area inside the photovoltaic converter. The first area and the second area are isolated from each other.

8. The photovoltaic converter according to claim 6, wherein: Also includes: A housing, wherein the first connection end, the third connection end, and the AC interface are arranged on a first side of the housing, and the second connection end, the communication end, and the electric meter interface are arranged on a second side of the housing; The first side is opposite to the second side.

9. The photovoltaic converter according to claim 8, characterized in that It also includes an outer mounting bracket and / or a back-hanging plate arranged on the shell.

10. A photovoltaic system, characterized in that: Comprising a photovoltaic module, a battery, a grid-connected inverter and the photovoltaic converter according to any one of claims 1 to 9; The photovoltaic converter is connected to the photovoltaic assembly, the battery and the grid-connected inverter respectively.

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