Photovoltaic inverter and photovoltaic inverter system
By using a parallel structure of multiple independent MPPT modules and inverter power modules, the problems of slow delivery and high cost of high power density photovoltaic inverter modules are solved, realizing the flexibility and low cost output of high power photovoltaic inverters.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHENZHEN SENERGY TECHNOLOGY CO LTD
- Filing Date
- 2025-06-24
- Publication Date
- 2026-06-16
Smart Images
Figure CN224367542U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the technical field of photovoltaic inverters, and more particularly to a photovoltaic inverter and a photovoltaic inverter system. Background Technology
[0002] With the increasing global demand for energy, there are more and more scenarios requiring high power for photovoltaic inverters. However, the production and delivery process of a single high-power-density photovoltaic inverter module that meets the current demand is long and costly, making it difficult to widely meet the demand for high-power photovoltaic inverters in different scenarios. Utility Model Content
[0003] The main objective of this application is to provide a photovoltaic inverter that aims to improve the output capability of the photovoltaic inverter to meet larger power demands.
[0004] To achieve the above objectives, this application proposes a photovoltaic inverter, which includes:
[0005] Parallel output terminals;
[0006] A total output terminal is electrically connected to the parallel output terminals, and the total output terminal is used to connect to external devices.
[0007] Multiple MPPT modules are provided, with their input terminals connected to a photovoltaic panel and the voltage output from the photovoltaic panel boosted before being output through their own output terminals.
[0008] Multiple inverter power modules are provided, and the output terminals of the multiple inverter power modules are electrically connected to parallel output terminals respectively; each inverter power module is used to invert the voltage connected to its own input terminal and then output it to the parallel output terminal through its own output terminal;
[0009] Wherein, the input terminal of the inverter power module is connected to the output terminal of at least one of the MPPT modules, and the output terminal of the MPPT module is connected to the input terminal of only one of the inverter power modules; or,
[0010] The input terminals of all the inverter power modules are electrically connected to the bus, and the output terminals of all the MPPT modules are electrically connected to the bus.
[0011] Optionally, the inverter power module includes a three-phase inverter power unit and three inverter inductors. The three output terminals of the three-phase inverter power unit are respectively connected to the first terminals of the three inverter inductors. The input terminal of the inverter power module includes the input terminal of the three-phase inverter power unit, and the output terminal of the inverter power module includes the second terminals of the three inverter inductors.
[0012] Optionally, the three-phase inverter power unit is composed of multiple discrete power devices.
[0013] Optionally, the three-phase inverter power unit is at least one of a full-bridge inverter topology, a half-bridge inverter topology, a T-type three-level inverter topology, and an I-type three-level inverter topology.
[0014] Optionally, the inverter power module further includes an output filter circuit, which is electrically connected to the path between the parallel output terminal and the total output terminal.
[0015] Optionally, the inverter power module further includes: multiple output filter circuits, each of which is electrically connected to a path between the output terminal and the parallel output terminal of the multiple inverter power modules.
[0016] Optionally, the inverter power module further includes a switching circuit, which is connected in series in the path between the output terminals of the plurality of inverter power modules and the total output terminal.
[0017] Optionally, the switching circuit is connected in series in the path between the parallel output terminal and the total output terminal;
[0018] The switching circuit is used to connect or disconnect the path between the parallel output terminal and the total output terminal.
[0019] Optionally, the switching circuit includes multiple switching units, and the switching unit is provided in the path between the output terminal of each inverter power module and the parallel output terminal;
[0020] The switching unit is used to connect or disconnect the path between the corresponding output terminal of the inverter power module and the parallel output terminal.
[0021] This application also proposes a photovoltaic inverter system, including a photovoltaic inverter as described in any of the preceding claims.
[0022] This photovoltaic inverter includes: a parallel output terminal, a total output terminal, multiple MPPT modules, and multiple inverter power modules. The total output terminal and the parallel output terminal are electrically connected, and the total output terminal is used to connect to external equipment. The input terminal of each MPPT module is connected to a photovoltaic panel, and the voltage output from the photovoltaic panel is boosted and then output through its own output terminal. The output terminals of the multiple inverter power modules are electrically connected to the parallel output terminal. Each inverter power module inverts the voltage connected to its own input terminal and then outputs it to the parallel output terminal through its own output terminal. Specifically, the input terminal of each inverter power module is connected to the output terminal of at least one MPPT module, and the output terminal of each MPPT module is connected to the input terminal of only one inverter power module; alternatively, the input terminals of all inverter power modules are electrically connected to the bus, and the output terminals of all MPPT modules are also electrically connected to the bus. Therefore, in practical applications, in scenarios requiring high-power photovoltaic inverters, this photovoltaic inverter, composed of multiple individual inverter modules and multiple individual MPPT modules, can meet the demand for high-power photovoltaic inverters, thereby effectively improving the output capacity of the photovoltaic inverter. Meanwhile, compared with highly integrated, high-power-density photovoltaic inverter modules, the photovoltaic inverter of this application not only has a simpler architecture and lower cost, but also is easier to maintain when facing the failure of a single module or multiple modules. The individual modules are highly replaceable, suitable for the needs of high-power photovoltaic inverters in different scenarios, and easy to promote. Attached Figure Description
[0023] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0024] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0025] Figure 1 This is a schematic diagram of a circuit module of a photovoltaic inverter according to an embodiment of this application;
[0026] Figure 2 This is a schematic diagram of a circuit module of another embodiment of the photovoltaic inverter of this application;
[0027] Figure 3 This is a schematic diagram of a circuit module of another embodiment of the photovoltaic inverter of this application;
[0028] Figure 4 This is a schematic diagram of a circuit module of another embodiment of the photovoltaic inverter of this application;
[0029] Figure 5 This is a circuit module schematic diagram of another embodiment of the photovoltaic inverter of this application;
[0030] Figure 6 This is a schematic diagram of a circuit module of another embodiment of the photovoltaic inverter of this application;
[0031] Figure 7 For this application Figure 1 A schematic diagram of a specific circuit of an embodiment of a photovoltaic inverter is shown.
[0032] Figure 8 For this application Figure 4 The diagram shows a specific circuit diagram of one embodiment of a photovoltaic inverter.
[0033] Label Explanation:
[0034]
[0035] The purpose, features, and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation
[0036] It should be understood that the specific embodiments described herein are merely illustrative of the technical solutions of this application and are not intended to limit this application.
[0037] To better understand the technical solutions of this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.
[0038] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in the embodiments of this application are only used to explain the relative positional relationships and movement of the components in a specific posture (as shown in the attached figures). If the specific posture changes, the directional indicators will also change accordingly. It should be understood that although the steps in the flowcharts of the embodiments of this application are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders.
[0039] With the increasing global demand for energy, there are more and more scenarios requiring high power for photovoltaic inverters. However, the production and delivery process of a single high-power-density photovoltaic inverter module that meets the current demand is long and costly, making it difficult to widely meet the demand for high-power photovoltaic inverters in different scenarios.
[0040] Therefore, this application proposes a photovoltaic inverter, which includes:
[0041] Parallel output terminal 10;
[0042] A total output terminal 20 is electrically connected to the parallel output terminal 10, and the total output terminal 20 is used to connect to an external device.
[0043] Multiple MPPT modules 30 are provided. The input terminals of each MPPT module 30 are used to connect to a photovoltaic panel, and the voltage output by the photovoltaic panel is boosted and then output through its own output terminal.
[0044] Multiple inverter power modules 40 are provided, and the output terminals of the multiple inverter power modules 40 are electrically connected to the parallel output terminal 10 respectively; each inverter power module 40 is used to invert the voltage connected to its own input terminal and output it to the parallel output terminal 10 through its own output terminal.
[0045] In this configuration, the input terminal of the inverter power module 40 is connected to the output terminal of at least one of the MPPT modules 30, and the output terminal of the MPPT module 30 is connected to the input terminal of only one of the inverter power modules 40; or,
[0046] The input terminals of all the inverter power modules 40 are electrically connected to the bus, and the output terminals of all the MPPT modules 30 are electrically connected to the bus.
[0047] In this embodiment, the external device may include an external power receiving device, an external power source, an external power grid, or an external energy storage device, etc. The MPPT (Maximum Power Point Tracking) module can be implemented using an MPPT chip and a boost circuit. The MPPT chip can adjust the operating point of the photovoltaic panel, allowing it to output maximum power under different conditions; the boost circuit can be formed using a boost chip and its related peripheral circuits, or by constructing it from electronic components such as inductors and switching transistors. For example, see reference... Figure 7 and Figure 8 As shown, the MPPT module 30 includes an MPPT chip (not shown) for connecting to a photovoltaic panel and a boost circuit for boosting the voltage output from the photovoltaic panel via the MPPT chip. The boost circuit consists of discrete components: an inductor, a switching transistor, and a diode. Thus, using discrete components to construct the boost circuit in the MPPT module 30 effectively improves the maintenance convenience and scalability of the MPPT module 30.
[0048] Optionally, the inverter power module 40 can be a three-phase inverter power module 40, which inverts the voltage received at its input terminal into the required three-phase AC voltage before outputting it. In one embodiment, refer to Figure 1 , Figure 7 and Figure 8 As shown, the inverter power module 40 includes a three-phase inverter power unit 41 and three inverter inductors. The three output terminals of the three-phase inverter power unit 41 are respectively connected to the first terminals of the three inverter inductors. The input terminal of the inverter power module 40 includes the input terminal of the three-phase inverter power unit 41, and the output terminal of the inverter power module 40 includes the second terminals of the three inverter inductors. In this embodiment, the three-phase inverter power unit 41 can be implemented by a three-phase inverter chip, or it can be composed of multiple discrete power devices, such as those shown in the reference diagram. Figure 7 The three-phase inverter power unit 41 consists of twelve switching transistors, which can be implemented using MOSFETs, IGBTs, power transistors, etc. This configuration, compared to highly integrated three-phase inverter chips, not only makes the three-phase inverter power unit 41 easier to maintain and dissipate heat, but also provides higher power flexibility and lower cost. Optionally, the three-phase inverter power unit 41 can be at least one of a full-bridge inverter topology, a half-bridge inverter topology, a T-type three-level inverter topology, or an I-type three-level inverter topology.
[0049] Alternatively, in another embodiment, the inverter power module 40 may also be a single-phase inverter power module 40.
[0050] Optionally, refer to Figure 1 and Figure 7 As shown, in one embodiment, the input terminals of all the inverter power modules 40 are electrically connected to the bus, and the output terminals of all the MPPT modules 30 are electrically connected to the bus. In this embodiment, the output terminals of all MPPT modules 30 and the input terminals of all the inverter power modules 40 are connected to the same DC bus. This arrangement allows multiple MPPT modules 30 to share the same output bus capacitor, thereby simplifying the circuit architecture and reducing the circuit construction cost while meeting the high-power requirements of photovoltaic inverters. (Reference) Figure 1 ,by Figure 1Taking this as an example, the number of MPPT modules 30 can be N (N greater than or equal to 2), and the number of inverter power modules 40 can be M (M greater than or equal to 2). The number of MPPT modules 30 can be greater than, less than, or equal to the number of inverter power modules 40. In practical operation, up to N MPPT modules 30 and up to M inverter power modules 40 can work together, allowing multiple MPPT modules to operate simultaneously to increase the overall output power of the photovoltaic panel. Simultaneously, multiple inverter power modules 40 operate simultaneously and output in parallel to achieve high-power output. Thus, the photovoltaic inverter of this application can meet the needs of high-power photovoltaic inverters by outputting multiple MPPT modules 30 in parallel and multiple inverter power modules 40 in parallel.
[0051] Optionally, refer to Figure 4 and Figure 8 As shown, in another embodiment of this application, the input terminal of the inverter power module 40 is connected to the output terminal of at least one of the MPPT modules 30, and the output terminal of the MPPT module 30 is connected to the input terminal of only one of the inverter power modules 40. For example, see Reference Figure 8 In the specific circuit shown, the input terminal of each inverter power module 40 is electrically connected to the output terminals of two MPPT modules 30. With this configuration, the input bus of each power module is independent, making the MPPT module 30 at the front end of each power module easy to adjust and maintain, thus offering high flexibility. (Reference) Figure 4 ,by Figure 4 Taking this as an example, the number of MPPT modules 30 connected in parallel to the input terminal of each inverter power module 40 can be N (N is greater than or equal to 2), and the number of inverter power modules 40 can be M (M is greater than or equal to 2). The number of MPPT modules 30 can be greater than, less than, or equal to the number of inverter power modules 40. In practical operation, each inverter power module 40 can have up to N MPPT modules 30, and up to M inverter power modules 40 working together. This allows multiple MPPT modules 30 to work together, increasing the overall output power of the photovoltaic panel. Simultaneously, multiple inverter power modules 40 work simultaneously and output in parallel to achieve high-power output. Therefore, the photovoltaic inverter of this application can meet the needs of high-power photovoltaic inverters by outputting multiple MPPT modules 30 in parallel and multiple inverter power modules 40 in parallel.
[0052] In summary, the photovoltaic inverter of this application includes: a parallel output terminal 10, a total output terminal 20, multiple MPPT modules 30, and multiple inverter power modules 40. The total output terminal 20 and the parallel output terminal 10 are electrically connected, and the total output terminal 20 is used to connect to external devices. The input terminal of each MPPT module 30 is used to connect to a photovoltaic panel, and the voltage output from the photovoltaic panel is boosted and then output through its own output terminal. The output terminals of the multiple inverter power modules 40 are respectively electrically connected to the parallel output terminal 10. Each inverter power module 40 is used to invert the voltage connected to its own input terminal and then output it to the parallel output terminal 10 through its own output terminal. Specifically, the input terminal of each inverter power module 40 is connected to the output terminal of at least one MPPT module 30, and the output terminal of each MPPT module 30 is connected to the input terminal of only one inverter power module 40; alternatively, the input terminals of all inverter power modules 40 are respectively electrically connected to the bus, and the output terminals of all MPPT modules 30 are respectively electrically connected to the bus. Therefore, in practical applications, when facing scenarios requiring high-power photovoltaic (PV) inverters, the PV inverter of this application, composed of multiple individual inverter modules and multiple individual MPPT modules 30, can meet the demand for high-power PV inverters. Specifically, by using multiple MPPT modules 30 connected in parallel and multiple inverter power modules 40 outputting in parallel, the output capacity of the PV inverter is effectively improved, thus enabling it to meet the requirements of high-power PV inverters. Furthermore, compared to highly integrated, high-power-density PV inverter modules, the PV inverter of this application not only has a simpler architecture, lower cost, and is easier to construct, but also facilitates maintenance in the event of malfunctions in a single or multiple modules, and offers strong replaceability for individual modules.
[0053] Optionally, refer to Figure 1 and Figure 4 In one embodiment of this application, the inverter power module 40 further includes an output filter circuit 50, which is electrically connected to the parallel output terminal 10 and the total output terminal 20. In this embodiment, the output filter circuit 50 can be implemented using a capacitor. For example, refer to... Figure 1 and Figure 4 For the three-phase photovoltaic inverter shown in the figure, the output filter circuit 50 includes three capacitors. The first terminals of the three capacitors are electrically connected one-to-one with the three parallel connection points in the parallel output terminal 10 and the three output points in the total output terminal 20. The second terminals of the three capacitors are all grounded, for example, to the ground of the power grid to which the total output terminal 20 is connected. This configuration not only filters the three-phase AC voltage output from multiple inverter power modules 40 in parallel to reduce noise, but also saves on output filter capacitors, thus effectively simplifying the circuit structure.
[0054] Optionally, refer to Figure 2 , Figure 3 , Figure 5 and Figure 6 In another embodiment of this application, the inverter power module 40 further includes: a plurality of output filter circuits 50, wherein each of the plurality of output filter circuits 50 is electrically connected to a path between the output terminal and the parallel output terminal 10 of the plurality of inverter power modules 40. In this embodiment, the output filter circuits 50 can be implemented using the same capacitors as in the above embodiments. For example, refer to... Figure 2 , Figure 3 , Figure 5 and Figure 6 As shown in the diagram, the output filter circuit 50 is equipped with three capacitors for each inverter power module 40. The first terminals of the three capacitors are electrically connected one-to-one with the three paths between the three inverter inductors in each inverter power module 40 and the three parallel connection points in the parallel output terminal 10. This arrangement not only filters the three-phase AC voltage output by each inverter power module 40 to reduce noise, but also achieves a better output filtering effect for the entire photovoltaic inverter because the output voltage of each inverter power module 40 is filtered.
[0055] Based on any of the above embodiments, refer to Figures 1-8 In one embodiment of this application, the inverter power module 40 further includes a switching circuit 60, which is connected in series in the path between the output terminals of the plurality of inverter power modules 40 and the total output terminal 20.
[0056] In this embodiment, the switching circuit 60 can be implemented using multiple switching transistors, such as MOSFETs, IGBTs, power transistors, or other switching devices like relays and contactors. By controlling the state of the switching circuit 60, the connection and disconnection between the multiple inverter power modules 40 and the total output terminal 20 can be controlled, thereby controlling the output capacity of the photovoltaic inverter.
[0057] Optionally, in one embodiment, reference is made to... Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the switching circuit 60 is connected in series in the path between the parallel output terminal 10 and the total output terminal 20; the switching circuit 60 is used to connect or disconnect the path between the parallel output terminal 10 and the total output terminal 20.
[0058] In this embodiment, the switching circuit 60 is connected in series in the path between the parallel output terminal 10 and the total output terminal 20, thereby enabling output control of all inverter power modules 40. For example, refer to... Figure 1 , Figure 1The circuit includes three sets of switches connected in series at three parallel connection points in the parallel output terminal 10 and three output points in the total output terminal 20, forming three paths. Each set of switches includes two switches connected in series, providing redundancy and reducing the probability of protection failure due to switch sticking when protection is required. In practical operation, controlling the state of the switch circuit 60 is sufficient to control the output state of all inverter power modules 40. When the switch circuit 60 is open, the path between all inverter power modules 40 and the total output terminal 20 is broken, and the photovoltaic inverter stops outputting. When the switch circuit 60 is closed, the path between all inverter power modules 40 and the total output terminal 20 is closed, and the photovoltaic inverter resumes outputting. This configuration effectively reduces the number of switch circuits 60 used for output control, simplifies the circuit structure, and lowers circuit costs.
[0059] Alternatively, in another embodiment, reference is made to... Figure 3 and Figure 6 The switching circuit 60 includes a plurality of switching units 61, and each of the inverter power modules 40 is provided with a switching unit 61 in the path between the output terminal and the parallel output terminal 10; the switching unit 61 is used to turn on or off the path between the corresponding output terminal of the inverter power module 40 and the parallel output terminal 10.
[0060] In this embodiment, the switching unit 61 is implemented using multiple switching transistors, such as MOSFETs, IGBTs, power transistors, etc., or other switching devices such as relays and contactors. A switching unit 61 is provided at the output terminal of each inverter power module 40, enabling the photovoltaic inverter to adaptively select an appropriate number of inverter power modules 40 to perform parallel output tasks based on current power demand or health conditions, thereby further improving the flexibility of photovoltaic inverter operation. For example, refer to... Figure 6 In each of the three paths corresponding to the output terminal of each inverter power module 40 and the parallel output terminal 10, two switches are connected in series. With this configuration, the output and input of each inverter power module 40 are set independently, thereby further improving the flexibility of photovoltaic inverter operation.
[0061] This application also proposes a photovoltaic inverter system, including a photovoltaic inverter as described in any of the preceding claims.
[0062] It is worth noting that since the photovoltaic inverter system of this application includes the aforementioned photovoltaic inverter, the photovoltaic inverter system of this application also includes all embodiments of the aforementioned photovoltaic inverter and the effects brought about by each embodiment, which will not be repeated here.
[0063] The above description is only a part of the embodiments of this application and does not limit the patent scope of this application. All equivalent structural transformations made under the technical concept of this application and using the contents of the specification and drawings of this application, or direct / indirect applications in other related technical fields, are included in the patent protection scope of this application.
Claims
1. A photovoltaic inverter, characterized in that, The photovoltaic inverter includes: Parallel output terminals; A total output terminal is electrically connected to the parallel output terminals, and the total output terminal is used to connect to external devices. Multiple MPPT modules are provided, with their input terminals connected to a photovoltaic panel and the voltage output from the photovoltaic panel boosted before being output through their own output terminals. Multiple inverter power modules are provided, and the output terminals of the multiple inverter power modules are electrically connected to parallel output terminals respectively; each inverter power module is used to invert the voltage connected to its own input terminal and then output it to the parallel output terminal through its own output terminal; Wherein, the input terminal of the inverter power module is connected to the output terminal of at least one of the MPPT modules, and the output terminal of the MPPT module is connected to the input terminal of only one of the inverter power modules; or, The input terminals of all the inverter power modules are electrically connected to the bus, and the output terminals of all the MPPT modules are electrically connected to the bus.
2. The photovoltaic inverter as described in claim 1, characterized in that, The inverter power module includes a three-phase inverter power unit and three inverter inductors. The three output terminals of the three-phase inverter power unit are respectively connected to the first terminals of the three inverter inductors. The input terminal of the inverter power module includes the input terminal of the three-phase inverter power unit, and the output terminal of the inverter power module includes the second terminals of the three inverter inductors.
3. The photovoltaic inverter as described in claim 2, characterized in that, The three-phase inverter power unit is composed of multiple discrete power devices.
4. The photovoltaic inverter as described in claim 2, characterized in that, The three-phase inverter power unit is at least one of the following: full-bridge inverter topology, half-bridge inverter topology, T-type three-level inverter topology, and I-type three-level inverter topology.
5. The photovoltaic inverter as described in claim 1, characterized in that, The inverter power module further includes an output filter circuit, which is electrically connected to the parallel output terminal and the total output terminal.
6. The photovoltaic inverter as described in claim 1, characterized in that, The inverter power module further includes: multiple output filter circuits, each of which is electrically connected to a path between the output terminal and the parallel output terminal of the inverter power module.
7. The photovoltaic inverter according to any one of claims 1-6, characterized in that, The inverter power module further includes a switching circuit, which is connected in series in the path between the output terminals of the multiple inverter power modules and the total output terminal.
8. The photovoltaic inverter as described in claim 7, characterized in that, The switching circuit is connected in series in the path between the parallel output terminal and the total output terminal; The switching circuit is used to connect or disconnect the path between the parallel output terminal and the total output terminal.
9. The photovoltaic inverter as described in claim 7, characterized in that, The switching circuit includes multiple switching units, and the switching unit is provided in the path between the output terminal of each inverter power module and the parallel output terminal. The switching unit is used to connect or disconnect the path between the corresponding output terminal of the inverter power module and the parallel output terminal.
10. A photovoltaic inverter system, characterized in that, Including the photovoltaic inverter as described in any one of claims 1-9.