A switching circuit and an inverter thereof
By designing a switching circuit, the single-phase inverter circuit can be flexibly switched between single-phase and split-phase power grids, solving the problem of high inverter adaptation costs in existing technologies and reducing production and maintenance costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- NINGBO GINLONG TECH
- Filing Date
- 2024-12-31
- Publication Date
- 2026-08-04
AI Technical Summary
In existing technologies, single-phase inverters and split-phase inverters need to be manufactured separately, resulting in high production and maintenance costs.
Design a switching circuit, including an input terminal group, a grid terminal group, a load terminal group, a conversion module, and a conversion switch group, capable of switching between single-phase grid and split-phase grid, and adaptable to single-phase inverter circuits and split-phase inverter circuits.
This enables single-phase inverter circuits to adapt to both single-phase and split-phase power grids, reducing production and maintenance costs and improving circuit flexibility and efficiency.
Smart Images
Figure CN119834350B_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of new energy power generation technology, and in particular to a switching circuit and its inverter. Background Technology
[0002] In some countries and regions, residential electricity uses a single-phase two-wire power grid, which consists of only one power line and one neutral line; while in other countries and regions, the power grid has a 240 / 120V single-phase three-wire power grid, which consists of two live wires L1 and L2 and one neutral wire N. The single-phase three-wire system is also known as a phase-separated power grid.
[0003] Currently, single-phase power grids typically use single-phase inverters adapted to them, while multi-phase power grids use multi-phase inverters adapted to them. However, manufacturing different inverters to adapt to single-phase or multi-phase power grids may result in higher production and subsequent operation and maintenance costs. Summary of the Invention
[0004] One object of the present invention is to provide a switching circuit that enables a single-phase inverter circuit to be adapted to both single-phase and split-phase power grids.
[0005] Another object of the present invention is to provide an inverter including the above-described switching circuit, so that the single-phase inverter circuit of the inverter can be adapted to both single-phase power grid and split-phase power grid.
[0006] To achieve at least one of the above objectives, the present invention adopts the following technical solution: a switching circuit, comprising: an input terminal group adapted to be connected to the output side of a single-phase inverter circuit; a grid terminal group adapted to be connected to the input side of a single-phase grid or a split-phase grid; a load terminal group adapted to be connected to the input side of a single-phase load or a split-phase load, the load terminal group being connected to the input terminal group to enable the grid to supply power to the load; and a conversion module, the conversion module including an interface for connecting to the input terminal group and an output for connecting to the load terminal group. A; a transfer switch group, the transfer switch group being connected between the outlet and the load terminal group, adapted to connect or disconnect the transfer module from the load terminal group; an input switch group, the input switch group being adapted to connect the input terminal group directly to the grid terminal group and the load terminal group, or to connect the input terminal group to the grid terminal group and the load terminal group through the transfer module; wherein, under the condition that the phase-separated grid is in off-grid mode, the input terminal group is adapted to connect to the load terminal group through the transfer module, so that the single-phase inverter circuit supplies power to the phase-separated load.
[0007] Preferably, the input terminal group includes a first input terminal A1 and a second input terminal A2; the input switch group includes a first input switch K1 and a second input switch K2, the first input switch K1 is adapted to switch between neutral, position a1, and position a2, and the second input switch K2 is adapted to switch between neutral, position b1, and position b2; when the first input switch K1 is in position a2 and the second input switch K2 is in position b1, the first input terminal A1 and the second input terminal A2 are adapted to be connected to the input of the conversion module respectively; when the first input switch K1 is in position a1 and the second input switch K2 is in position b2, the first input terminal A1 and the second input terminal A2 are adapted to be directly connected to the grid terminal group; when the first input switch K1 and the second input switch K2 are in neutral, the switching circuit is disconnected from the single-phase inverter circuit.
[0008] As a preferred embodiment, the input terminal group further includes a third input terminal A3, so that the input side of the switching circuit is adapted to be connected to the output side of a single-phase inverter circuit or a split-phase inverter circuit. The switch group also includes a third input switch K3, which is adapted to switch between an open position and a closed position. By switching the first input switch K1, the second input switch K2 and the third input switch K3, the switching circuit can be connected to or disconnected from the inverter circuit.
[0009] As a preferred embodiment, the switching circuit further includes a motor terminal group and a motor switch group. The motor terminal group is adapted to be connected to a generator, and the motor switch group is connected between the motor terminal group and the input port of the conversion module, so that the motor terminal group can be connected or disconnected from the input side of the conversion module.
[0010] As a preferred embodiment, the switching circuit further includes several branches, which are adapted to connect the grid terminal group and the load terminal group accordingly; the input switch group is adapted to connect the input terminal group to the branch, or to the input port, or to disconnect the switching circuit from the inverter circuit; the conversion switch group is adapted to connect or disconnect the output port from the branch respectively, so that the conversion module is connected or disconnected from the load terminal group.
[0011] As a preferred embodiment, the input ports of the conversion module include input ports #1 and #2. When the first input switch K1 is set to position a2 and the second input switch K2 is set to position b1, the first input terminal A1 and the second input terminal A2 can be connected to input ports #1 and #2 respectively. The output ports include output ports #3, #4 and #5. The conversion switch group includes a first conversion switch K4, a second conversion switch K5 and a third conversion switch K6 adapted to switch between open and closed positions respectively. The first conversion switch K4, the second conversion switch K5 and the third conversion switch K6 can be connected to output ports #3, #4 and #5 respectively, so that the conversion module can be connected to or disconnected from the load terminal group.
[0012] As a preferred embodiment, the switching circuit further includes a grid-connected switch group connected between the input switch group and the grid terminal group to enable the grid to switch between off-grid mode and grid-connected mode.
[0013] As a preferred embodiment, the grid-connected switch group includes a first grid-connected switch K7 and a second grid-connected switch K8, which are adapted to switch between an open position and a closed position, respectively, so as to connect or disconnect the switching circuit from the power grid.
[0014] As a preferred embodiment, the conversion module includes a coupling transformer or an isolation transformer.
[0015] To achieve at least one of the above objectives, the technical solution adopted by the present invention is as follows: an inverter, comprising: a switching circuit as described above; a power conversion circuit, wherein the output side of the power conversion circuit is connected to the input side of the switching circuit.
[0016] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0017] (1) The input terminal of the switching circuit is adapted to be connected to the output side of the single-phase inverter circuit, and the grid terminal group is adapted to be connected to the input side of the single-phase grid and / or split-phase grid, so that the single-phase inverter circuit can be adapted to both single-phase grid and split-phase grid at the same time.
[0018] (2) The load terminal group is suitable for connection to the input side of a single-phase load or a split-phase load, thereby enabling the single-phase inverter circuit to simultaneously adapt to both single-phase and split-phase loads. Furthermore, the load terminal group is connected to the input terminal group so that the power grid can supply power to the load. That is, under the condition of grid connection, the power grid and the single-phase inverter circuit can supply power to the load simultaneously, and under the condition of grid off-grid mode, the single-phase inverter circuit can supply power to the load. Attached Figure Description
[0019] Figure 1 This is a schematic diagram showing the connection between the switching circuit and the power conversion circuit, the power grid, and the load in some embodiments of this application.
[0020] Figure 2 This is a schematic diagram showing the connection between the switching circuit and a single-phase circuit, a single-phase power grid, and a single-phase load in some embodiments of this application.
[0021] Figure 3 This is a schematic diagram showing the connection between the switching circuit and a single-phase circuit and a single-phase load in some embodiments of this application.
[0022] Figure 4 This is a schematic diagram showing the connection between the switching circuit and a single-phase circuit, a split-phase power grid, and a split-phase load in some embodiments of this application.
[0023] Figure 5 This is a schematic diagram showing the connection between the switching circuit and the single-phase circuit and the split-phase load in some embodiments of this application.
[0024] Figure 6 This is a schematic diagram showing the connection between the switching circuit and a single-phase circuit, a split-phase power grid, and a split-phase load in some other embodiments of this application.
[0025] Figure 7 This is a schematic diagram of a single-phase inverter circuit according to some embodiments of this application.
[0026] Figure 8 This is a schematic diagram showing the connection between the switching circuit and the generator, the phased power grid and the phased load in some embodiments of this application.
[0027] Figure 9 This is a schematic diagram showing the connection between the switching circuit and the generator and the phase load in some embodiments of this application.
[0028] Figure 10 This is a schematic diagram showing the connection between the switching circuit and a single / phase circuit, a single-phase power grid, and a single-phase load in some embodiments of this application.
[0029] Figure 11 This is a schematic diagram showing the connection between the switching circuit and the phase-splitting circuit, the single-phase power grid, and the single-phase load in some embodiments of this application.
[0030] Figure 12 This is a schematic diagram showing the connection between the switching circuit, the phase-splitting circuit, and the single-phase load in some embodiments of this application.
[0031] Figure 13 This is a schematic diagram showing the connection between the switching circuit and a single / phase circuit, a phased power grid, and a phased load in some embodiments of this application.
[0032] Figure 14 This is a schematic diagram showing the connection between the switching circuit and the phase circuit, the phase power grid and the phase load in some embodiments of this application.
[0033] Figure 15 This is a schematic diagram showing the connection between the switching circuit, the phase-splitting circuit, and the phase-splitting load in some embodiments of this application.
[0034] Figure 16 This is a schematic diagram showing the connection between the switching circuit and the phase circuit, the phase power grid, and the phase load in some other embodiments of this application.
[0035] Figure 17 This is a schematic diagram of a phase-split inverter circuit according to some embodiments of this application.
[0036] Figure 18 This is a schematic diagram of the conversion module in some embodiments of this application.
[0037] In the diagram: 101, Inverter; 102, Power conversion circuit; 103, Switching circuit; 104, Conversion module; 201, First branch; 202, Second branch; 203, Third branch. Detailed Implementation
[0038] The present invention will now be further described in conjunction with specific embodiments. It should be noted that, without conflict, the various embodiments or technical features described below can be arbitrarily combined to form new embodiments.
[0039] It should be noted that the terms "first," "second," etc., in the specification and claims of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.
[0040] The terms “comprising” and “having”, and any variations thereof, in the specification and claims of this application are intended to cover non-exclusive inclusion, 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 that are explicitly listed, but may include other steps or units that are not explicitly listed or that are inherent to such process, method, product, or device.
[0041] A switching circuit 103, such as Figures 1-6As shown, the system includes: an input terminal group, a grid terminal group, a load terminal group, a conversion module 104, a transfer switch group, and an input switch group. The input terminal group is adapted to connect to the output side of a single-phase inverter circuit. The grid terminal group is adapted to connect to the input side of a single-phase grid or a split-phase grid. The load terminal group is adapted to connect to the input side of a single-phase load or a split-phase load. The load terminal group is connected to the input terminal group to allow the grid to supply power to the load. The conversion module 104 includes an input port for connecting to the input terminal group and an output port for connecting to the load terminal group. The transfer switch group is connected between the output port and the load terminal group to allow the conversion module 104 to connect or disconnect from the load terminal group. The input switch group is adapted to allow the input terminal group to be directly connected to the grid terminal group and the load terminal group, or to be connected to the grid terminal group and the load terminal group through the conversion module 104. Wherein, under the condition that the split-phase grid is in off-grid mode, the input terminal group is adapted to be connected to the load terminal group through the conversion module 104 to allow the single-phase inverter circuit to supply power to the split-phase load.
[0042] It should be understood that the input terminal group of the switching circuit 103 is adapted to be connected to the output side of the single-phase inverter circuit. The grid terminal group of the switching circuit 103 is adapted to be connected to the input side of the single-phase grid and also to the input side of the split-phase grid, thereby enabling the single-phase inverter circuit to be adapted to both single-phase grids and split-phase grids simultaneously.
[0043] Furthermore, the load terminal group of the switching circuit 103 is adapted to be connected to the input side of a single-phase load or a split-phase load, thereby enabling the single-phase inverter circuit to simultaneously adapt to both single-phase and split-phase loads. Even further, the load terminal group is connected to the input terminal group so that the power grid can supply power to the load. That is, under grid-connected conditions, the power grid and the single-phase inverter circuit can simultaneously supply power to the load; under off-grid conditions, the single-phase inverter circuit can supply power to the load.
[0044] It should be understood that the specific structure and working principle of the single-phase inverter circuit are well known to those skilled in the art, and therefore will not be described in detail here. This application does not impose specific restrictions on the specific structure of the single-phase inverter circuit.
[0045] Specifically, with Figure 7 Taking the single-phase inverter circuit shown as an example, the input side of the single-phase inverter circuit is suitable for connection with a power generation module or an energy storage module, etc., and this application does not impose specific limitations on this. The output side of the single-phase inverter circuit includes terminals A1' and A2'.
[0046] It is worth mentioning that the input terminal group of the switching circuit 103 includes at least two input terminals for one-to-one connection with terminals A1' and A2'. The grid terminal group includes at least three grid terminals for connection with the input side of a single-phase grid or a split-phase grid. The load terminal group includes at least three load terminals for connection with the input side of a single-phase load or a split-phase load.
[0047] Under the condition that the power grid is a single-phase power grid, such as Figure 2 and Figure 3 As shown, two of the three grid terminals are adapted to be connected one-to-one with the phase line Gird_L and neutral line Gird_N of the single-phase grid, and the input switch group is adapted to connect the phase line Gird_L and neutral line Gird_N one-to-one with the A1' and A2' terminals of the single-phase inverter circuit. Furthermore, the load is a single-phase load, and two of the three load terminals are adapted to be connected one-to-one with the phase line Buckup_L and neutral line Buckup_N of the single-phase load, and the input switch group is adapted to connect the phase line Buckup_L and neutral line Buckup_N one-to-one with the A1' and A2' terminals of the single-phase inverter circuit. It should be understood that because the load terminal group is connected to the input terminal group, the phase line Gird_L and neutral line Gird_N of the single-phase grid are thus connected one-to-one with the phase line Buckup_L and neutral line Buckup_N of the single-phase load, allowing the single-phase inverter circuit and the single-phase load circuit to jointly supply power to the single-phase load.
[0048] Under the condition that the power grid is a phase-separated power grid, such as Figure 4 As shown, the three grid terminals are adapted to be connected one-to-one with the phase lines Gird_L1, Gird_L2 and neutral line Gird_N of the split-phase grid, and the input switch group is adapted to connect the phase lines Gird_L1 and Gird_L2 one-to-one with the A1' and A2' terminals of the single-phase inverter circuit. Furthermore, the load is a split-phase load, and the three load terminals are adapted to be connected one-to-one with the phase lines Buckup_L1, Buckup_L2 and neutral line Buckup_N of the split-phase load, and the input switch group is adapted to connect the phase lines Buckup_L1 and Buckup_L2 one-to-one with the A1' and A2' terminals of the single-phase inverter circuit. It should be understood that, since the load terminal group is connected to the input terminal group, the phase lines Gird_L1, Gird_L2 and neutral line Gird_N of the phase grid can be connected one-to-one with the phase lines Buckup_L1, Buckup_L2 and neutral line Buckup_N of the phase load, so that the single-phase inverter circuit and the phase load circuit can jointly supply power to the phase load.
[0049] It is worth mentioning that, such as Figure 5 As shown, under the condition that the split-phase power grid is in off-grid mode, the input switch group is adapted to connect the A1' and A2' terminals of the single-phase inverter circuit to the corresponding input of the conversion module 104, and the conversion switch group is adapted to connect the phase lines Buckup_L1, Buckup_L2 and neutral line Buckup_N of the split-phase load to the corresponding output of the conversion module 104, so that the single-phase inverter circuit can supply power to the split-phase load.
[0050] In some embodiments, such as Figures 2-5 As shown, the input terminal group includes a first input terminal A1 and a second input terminal A2, wherein the first input terminal A1 is connected to the A1' terminal of the single-phase inverter circuit, and the second input terminal A2 is connected to the A2' terminal of the single-phase inverter circuit. Further, the input switch group includes a first input switch K1 and a second input switch K2. The first input switch K1 is adapted to switch between neutral, position a1, and position a2, and the second input switch K2 is adapted to switch between neutral, position b1, and position b2. When the first input switch K1 is in position a2 and the second input switch K2 is in position b1, the first input terminal A1 and the second input terminal A2 are adapted to be connected to the input ports of the conversion module 104, respectively. When the first input switch K1 is in position a1 and the second input switch K2 is in position b2, the first input terminal A1 and the second input terminal A2 are adapted to be directly connected to the grid terminal group. When the first input switch K1 and the second input switch K2 are in neutral, the switching circuit 103 is disconnected from the single-phase inverter circuit.
[0051] Furthermore, the grid terminal group includes a first grid terminal B1, a second grid terminal B2 and a third grid terminal B3, the load terminal includes a first load terminal C1, a second load terminal C2 and a third load terminal C3, the input of the conversion module 104 includes inputs #1 and #2, and the output of the conversion module 104 includes outputs #3, #4 and #5.
[0052] In at least one embodiment, such as Figure 2 As shown, under the conditions of a single-phase power grid and a single-phase load, the first power grid terminal B1 is connected to the phase line Gird_L of the single-phase power grid, the second power grid terminal B2 is connected to the neutral line Gird_N of the single-phase power grid, and the third power grid terminal B3 is left floating. Simultaneously, the first power grid terminal B1 is connected to the first input terminal A1 via the first input switch K1 located at position a1, and the second power grid terminal B2 is connected to the second input terminal A2 via the second input switch K2 located at position b2. This connects the phase line Gird_L to terminal A1' and the neutral line Gird_N to terminal A2'.
[0053] Furthermore, the first load terminal C1 is connected to the phase line Buckup_L of the single-phase load, the second load terminal C2 is connected to the neutral line Buckup_N of the single-phase load, and the third load terminal C3 is left floating. Simultaneously, the first load terminal C1 is connected to the first input terminal A1 via the first input switch K1 located at position a1, and the second load terminal C2 is connected to the second input terminal A2 via the second input switch K2 located at position b2, thereby connecting the phase line Buckup_L to terminal A1' and the neutral line Buckup_N to terminal A2'.
[0054] Furthermore, the first grid terminal B1 is connected to the first load terminal C1, and the second grid terminal B2 is connected to the second load terminal C2, so that the phase line Gird_L of the single-phase grid is connected to the phase line Buckup_L of the single-phase load, and the neutral line Gird_N of the single-phase grid is connected to the neutral line Buckup_N of the single-phase load, thereby enabling the single-phase inverter circuit and the single-phase grid to supply power to the single-phase load simultaneously.
[0055] This should be understandable, such as Figure 3 As shown, under the condition that the single-phase power grid is in off-grid mode, the A1' terminal of the single-phase inverter 101 can be connected to the phase line Buckup_L of the single-phase load through the first input terminal A1, the first input switch K1 set to position a1, and the first load terminal C1. Similarly, the A2' terminal of the single-phase inverter 101 can be connected to the neutral line Buckup_N of the single-phase load through the second input terminal A2, the second input switch K2 set to position b2, and the second load terminal C2, thereby enabling the single-phase inverter circuit to supply power to the single-phase load.
[0056] In at least one embodiment, such as Figure 4 As shown, under the condition that the power grid is a phase-separated power grid and the load is a phase-separated load, the first power grid terminal B1 is connected to the phase line Gird_L1 of the phase-separated power grid, the second power grid terminal B2 is connected to the phase line Gird_L2 of the phase-separated power grid, and the third power grid terminal B3 is connected to the neutral line Gird_N of the phase-separated power grid. The first power grid terminal B1 is connected to the first input terminal A1 through the first input switch K1 located at position a1, and the second power grid terminal B2 is connected to the second input terminal A2 through the second input switch K2 located at position b2, thereby connecting the phase line Gird_L1 to the A1' terminal and the phase line Gird_L2 to the A2' terminal.
[0057] Furthermore, the first load terminal C1 is connected to the phase line Buckup_L1 of the split-phase load, the second load terminal C2 is connected to the phase line Buckup_L2 of the split-phase load, and the third load terminal C3 is connected to the neutral line Buckup_N of the split-phase load. Simultaneously, the first load terminal C1 is connected to the first input terminal A1 via the first input switch K1 located at position a1, and the second load terminal C2 is connected to the second input terminal A2 via the second input switch K2 located at position b2. This connects phase line Buckup_L1 to terminal A1' and phase line Buckup_L2 to terminal A2'.
[0058] Furthermore, the first grid terminal B1 is connected to the first load terminal C1, the second grid terminal B2 is connected to the second load terminal C2, and the third grid terminal B3 is connected to the third load terminal C3. This ensures that the phase lines Gird_L1 and Gird_L2 of the phase-segment grid are connected one-to-one with the phase lines Buckup_L1 and Buckup_L2 of the phase-segment load, and the neutral line Gird_N of the phase-segment grid is connected to the neutral line Buckup_N of the phase-segment load. Thus, the single-phase inverter circuit and the phase-segment grid can simultaneously supply power to the phase-segment load. It is worth noting that the input terminal group is directly connected to the grid terminal group and the load terminal group, meaning the single-phase inverter circuit is directly connected to the phase-segment grid and the phase-segment load, which helps reduce power loss.
[0059] This should be understandable, such as Figure 5 As shown, under the condition that the split-phase power grid is in off-grid mode, the first input switch K1 is set to position a2, so that the first input terminal A1 is connected to the input port #1 of the conversion module 104, and the second input switch K2 is set to position b1, so that the second input terminal A2 is connected to the input port #2 of the conversion module 104. At the same time, the output ports #3, #4 and #5 are connected to the phase lines Buckup_L1, Buckup_L2 and neutral line Buckup_N of the split-phase load respectively through the conversion switch group, thereby enabling the single-phase inverter circuit to supply power to the split-phase load.
[0060] It is worth mentioning that, such as Figure 6 As shown, the phase-splitting power grid can also be connected to the single-phase inverter circuit via the conversion module 104. Specifically, the first input switch K1 is set to position a2, connecting the first input terminal A1 to input port #1 of the conversion module 104, and the second input switch K2 is set to position b1, connecting the second input terminal A2 to input port #2 of the conversion module 104. Simultaneously, output ports #3, #4, and #5 are connected to the phase lines Gird_L1, Gird_L2, and neutral line Gird_N of the phase-splitting circuit, respectively. It should be understood that when both the phase-splitting power grid and the phase-splitting load are connected to the single-phase inverter circuit via the conversion module 104, the input switches K1 and K2, and some of the conversion switches, can be omitted, simplifying the control of the switching circuit 103.
[0061] In some embodiments, such as Figure 8 and Figure 9 As shown, the switching circuit 103 also includes a motor terminal group and a motor switch group. The motor terminal group is adapted to be connected to the generator, and the motor switch group is connected between the motor terminal group and the input of the conversion module 104, so that the motor terminal group can be connected or disconnected from the input side of the conversion module 104.
[0062] Specifically, such as Figure 8 and Figure 9As shown, the motor terminal group includes a first motor terminal D1 and a second motor terminal D2. The first motor terminal D1 is connected to the generator's phase line Gen_L, and the second motor terminal D2 is connected to the generator's neutral line Gen_N. Further, the motor switch group includes a first motor switch K9 and a second motor switch K10. The first motor switch K9 is connected between the first motor terminal D1 and the input port #1 of the conversion module 104, and the second motor switch K10 is connected between the second motor terminal D2 and the input port #2 of the conversion module 104. It is worth noting that the first motor switch K9 and the second motor switch K10 are adapted to directly switch between open and closed positions, respectively, so that the motor's phase line Gen_L and neutral line Gen_N are disconnected or connected to the input ports #1 and #2 of the conversion module 104. It should be understood that the output ports #3, #4 and #5 of the conversion module 104 are connected one-to-one with the phase lines Buckup_L1, Buckup_L2 and neutral line Buckup_N of the load, thereby enabling the generator to supply power to the split-phase load.
[0063] In some embodiments, such as Figures 8-16 As shown, the input terminal group also includes a third input terminal A3, so that the input side of the switching circuit 103 is adapted to be connected to the output side of a single-phase inverter circuit or a split-phase inverter circuit. The switch group also includes a third input switch K3, which is adapted to switch between an open position and a closed position. By switching the first input switch K1, the second input switch K2 and the third input switch K3, the switching circuit 103 can be connected to or disconnected from the inverter circuit.
[0064] This should be understandable, such as Figure 8 and Figure 13 As shown, the input terminal group of the switching circuit 103 is adapted to be connected to the output side of the split-phase inverter circuit, and the grid terminal group is adapted to be connected to the input side of a single-phase grid or a split-phase grid, thereby enabling the split-phase inverter circuit to simultaneously adapt to both single-phase and split-phase grids. Furthermore, the load terminal group is adapted to be connected to the input side of a single-phase load or a split-phase load, thereby enabling the split-phase inverter circuit to simultaneously adapt to both single-phase and split-phase loads. Even further, the load terminal group is connected to the input terminal group so that the grid can supply power to the load.
[0065] It should be understood that the specific structure and working principle of the phase-splitting inverter circuit are well-known to those skilled in the art, and therefore will not be described in detail here. This application does not impose specific restrictions on the specific structure of the phase-splitting inverter circuit.
[0066] Specifically, with Figure 17 Taking the split-phase inverter circuit shown as an example, the input side of the split-phase inverter circuit is suitable for connection with a power generation module or an energy storage module, etc., and this application does not impose specific limitations on this. The output side of the split-phase inverter circuit includes terminals A1", A2", and A3".
[0067] It should be noted that, under the condition that the inverter circuit is a single-phase inverter circuit, the first input terminal A1 is connected to the A1' terminal of the single-phase inverter circuit, the second input terminal A2 is connected to the A2' terminal of the single-phase inverter circuit, and the third input terminal A3 is left floating. The specific connection method is as described above.
[0068] When the inverter circuit is a split-phase inverter circuit, the first input terminal A1 is connected to the A1” terminal of the split-phase inverter circuit, the second input terminal A2 is connected to the A2” terminal of the split-phase inverter circuit, and the third input terminal A3 is connected to the A3” terminal of the split-phase inverter circuit.
[0069] In at least one embodiment, such as Figure 11 As shown, under the conditions of a single-phase power grid and a single-phase load, the first power grid terminal B1 is connected to the phase line Gird_L of the single-phase power grid, the second power grid terminal B2 is connected to the neutral line Gird_N of the single-phase power grid, and the third power grid terminal B3 is left floating. Simultaneously, the first power grid terminal B1 is connected to the first input terminal A1 via the first input switch K1 located at position a1, and the second power grid terminal B2 is connected to the second input terminal A2 via the second input switch K2 located at position b2. This connects the phase line Gird_L to the A1” terminal and the neutral line Gird_N to the A2” terminal. It is worth noting that the input switch K3 is in the open-circuit position, thus allowing the A3” terminal of the split-phase inverter circuit to be left floating.
[0070] Furthermore, the first load terminal C1 is connected to the phase line Buckup_L of the single-phase load, the second load terminal C2 is connected to the neutral line Buckup_N of the single-phase load, and the third load terminal C3 is left floating. Simultaneously, the first load terminal C1 is connected to the first input terminal A1 via the first input switch K1 located at position a1, and the second load terminal C2 is connected to the second input terminal A2 via the second input switch K2 located at position b2, thereby connecting the phase line Buckup_L to the A1” terminal and the neutral line Buckup_N to the A2” terminal.
[0071] Furthermore, the first grid terminal B1 is connected to the first load terminal C1, and the second grid terminal B2 is connected to the second load terminal C2, so that the phase line Gird_L of the single-phase grid is connected to the phase line Buckup_L of the single-phase load, and the neutral line Gird_N of the single-phase grid is connected to the neutral line Buckup_N of the single-phase load, thereby enabling the split-phase inverter circuit and the single-phase grid to supply power to the single-phase load simultaneously.
[0072] This should be understandable, such as Figure 12As shown, under the condition that the single-phase power grid is in off-grid mode, the A1” terminal of the split-phase inverter circuit can be connected to the phase line Buckup_L of the single-phase load through the first input terminal A1, the first input switch K1 set to position a1, and the first load terminal C1. Similarly, the A2” terminal of the split-phase inverter circuit can be connected to the neutral line Buckup_N of the single-phase load through the second input terminal A2, the second input switch K2 set to position b2, and the second load terminal C2, thereby enabling the split-phase inverter circuit to supply power to the single-phase load.
[0073] In at least one embodiment, such as Figure 14 As shown, under the conditions of a phase-separated power grid and a phase-separated load, the first power grid terminal B1 is connected to the phase line Gird_L1 of the phase-separated power grid, the second power grid terminal B2 is connected to the phase line Gird_L2 of the phase-separated power grid, and the third power grid terminal B3 is connected to the neutral line Gird_N of the phase-separated power grid. Simultaneously, the first power grid terminal B1 is connected to the first input terminal A1 via the first input switch K1 in position a1, the second power grid terminal B2 is connected to the second input terminal A2 via the second input switch K2 in position b2, and the third power grid terminal B3 is connected to the third input terminal A3 via the third input switch K3 in the closed position. This results in the phase line Gird_L1 being connected to the A1” terminal, the phase line Gird_L2 being connected to the A2” terminal, and the neutral line Gird_N being connected to the A3” terminal.
[0074] Furthermore, the first load terminal C1 is connected to the phase line Buckup_L1 of the phase-splitting load, the second load terminal C2 is connected to the phase line Buckup_L2 of the phase-splitting load, and the third load terminal C3 is connected to the neutral line Buckup_N of the phase-splitting load. Simultaneously, the first load terminal C1 is connected to the first input terminal A1 via the first input switch K1 in position a1, the second load terminal C2 is connected to the second input terminal A2 via the second input switch K2 in position b2, and the third load terminal C3 is connected to the third input terminal A3 via the third input switch K3 in the closed position. This connects the phase line Buckup_L1 to the A1” terminal, the phase line Buckup_L2 to the A2” terminal, and the neutral line Buckup_N to the A3” terminal.
[0075] Furthermore, as mentioned above, the phase line Gird_L1 of the split-phase power grid is connected to the phase line Buckup_L1 of the split-phase load, the phase line Gird_L2 of the split-phase power grid is connected to the phase line Buckup_L2 of the split-phase load, and the neutral line Gird_N of the split-phase power grid is connected to the neutral line Buckup_N of the split-phase load. Thus, the single-phase inverter circuit and the single-phase power grid can simultaneously supply power to the single-phase load.
[0076] This should be understandable, such as Figure 15As shown, under off-grid conditions, the A1” terminal of the phase inverter circuit is connected to the phase line Buckup_L1 of the phase load via the first input terminal A1, the first input switch K1 in position a1, and the first load terminal C1. The A2” terminal of the phase inverter circuit is connected to the phase line Buckup_L1 of the phase load via the second input terminal A2, the second input switch K2 in position b2, and the second load terminal C2. The A3” terminal of the phase inverter circuit is connected to the neutral line Buckup_N of the phase load via the third input terminal A3, the third input switch K3 in the closed position, and the third load terminal C3, thereby enabling the phase inverter circuit to supply power to the phase load.
[0077] It is worth mentioning that, such as Figure 16 As shown, under the condition that the phase inverter circuit is connected to the phase grid and the phase load, the conversion module 104 can be omitted, so that the switching circuit 103 is simpler.
[0078] In some embodiments, the switching circuit 103 further includes several branches, which are adapted to connect the grid terminal group and the load terminal group respectively, so that the grid can supply power to the load. Further, the input switch group is adapted to connect the input terminal group to the branch, or to the input port, or to disconnect the switching circuit 103 from the inverter circuit; the changeover switch group is adapted to connect or disconnect the output port from the branch respectively, so that the conversion module 104 is connected or disconnected from the load terminal group.
[0079] Specifically, such as Figures 2-5 and Figures 8-15 As shown, the plurality of branches include a first branch 201, a second branch 202 and a third branch 203. The first branch 201 is adapted to connect a first input terminal A1, a first power grid terminal B1 and a first load terminal C1; the second branch 202 is adapted to connect a second input terminal A2, a second power grid terminal B2 and a second load terminal C2; and the third branch 203 is adapted to connect a third input terminal A3, a third power grid terminal B3 and a third load terminal C3.
[0080] Furthermore, the first input switch K1 is disposed between the first input terminal A1, the first branch 201 and the input port #1 of the conversion module 104, so that the first input terminal A1 is adapted to be connected to the first branch 201 or the input port #1; the second input switch K2 is disposed between the second input terminal A2, the second branch 202 and the input port #2 of the conversion module 104, so that the second input terminal A2 is adapted to be connected to the second branch 202 or the input port #2; and the third input switch K3 is disposed between the third input terminal A3 and the third branch 203.
[0081] In some embodiments, such as Figures 2-5 and Figures 8-15As shown, the changeover switch group includes a first changeover switch K4, a second changeover switch K5, and a third changeover switch K6, which are adapted to switch between open and closed positions respectively. The first changeover switch K4, the second changeover switch K5, and the third changeover switch K6 can be connected to the outlet #3, the outlet #4, and the outlet #5 respectively, so that the changeover module 104 can be connected to or disconnected from the load end group.
[0082] In at least one embodiment, a first changeover switch K4 is disposed between outlet #4 and the first branch 201, so that outlet #4 is adapted to be connected to the first load terminal C1; a second changeover switch K5 is disposed between outlet #5 and the second branch 202, so that outlet #5 is adapted to be connected to the second load terminal C2; and a third changeover switch K6 is disposed between outlet #6 and the third branch 203, so that outlet #6 is adapted to be connected to the third load terminal C3.
[0083] It should be understood that by connecting each input terminal, each power grid terminal, and each load terminal one by one through the first branch 201, the second branch 202, and the third branch 203, and by connecting each output of the conversion module 104 to each load terminal one by one through the first branch 201, the second branch 202, and the third branch 203, the circuit of the switching circuit 103 is made simpler, thereby improving the reliability of the switching circuit 103.
[0084] It is worth mentioning that other branches can also be set up so that the outlets #4, #5, and #6 are connected one-to-one with the first load terminal C1, the second load terminal C2, and the third load terminal C3. That is to say, the outlets of the conversion module 104 are not connected to branches, but are connected one-to-one with each load terminal through other branches. This application does not impose specific restrictions on this.
[0085] In some embodiments, such as Figures 2-5 and Figures 8-15 As shown, the switching circuit 103 also includes a grid-connected switch group, which is connected between the input switch group and the grid terminal group to enable the grid to switch between off-grid mode and grid-connected mode. Specifically, the grid-connected switch group is connected between the branch and the grid resistor, and is adapted to switch between open and closed positions.
[0086] In practical terms, if the grid-connected switch group is in the closed position, the power grid is in grid-connected mode, and the inverter circuit and the power grid can supply power to the load simultaneously, as described above. If the grid-connected switch group is in the open position, the power grid is in off-grid mode, allowing the inverter circuit to supply power to the load independently, as described above.
[0087] In at least one embodiment, such as Figures 2-5 and Figures 8-15As shown, the grid-connected switch group includes a first grid-connected switch K7 and a second grid-connected switch K8. The first grid-connected switch K7 and the second grid-connected switch K8 are adapted to switch between an open position and a closed position, respectively, so that the switching circuit 103 is connected to or disconnected from the power grid. Specifically, the first grid-connected switch K7 is connected between the first branch 201 and the first power grid terminal B1, and the second grid-connected switch K8 is connected between the second branch 202 and the second power grid terminal B2.
[0088] It should be understood that, under the condition that the switching circuit 103 is connected to the single-phase power grid, as mentioned above, the first power grid terminal B1 is connected to the phase line Gird_L of the single-phase power grid, the second power grid terminal B2 is connected to the neutral line Gird_N of the single-phase power grid, and the third power grid terminal B3 is left floating. Furthermore, by setting the first grid-connected switch K7 and the second grid-connected switch K8 to the open position, the single-phase phase line Gird_L and the neutral line Gird_N are disconnected from the first branch 201 and the second branch 202. That is, the single-phase power grid's phase line Gird_L and neutral line Gird_N are disconnected from the load's phase line Buckup_L and neutral line Buckup_N, and also disconnected from the inverter circuit, allowing the power grid to be in off-grid mode.
[0089] With the switching circuit 103 connected to the phase-connected power grid, as described above, the first grid terminal B1 is connected to the phase line Gird_L1 of the phase-connected power grid, the second grid terminal B2 is connected to the phase line Gird_L2 of the phase-connected power grid, and the third grid terminal B3 is connected to the neutral line Gird_N of the phase-connected power grid. Furthermore, by setting the first grid-connected switch K7 and the second grid-connected switch K8 to the open position, the phase lines Gird_L1 and Gird_L2 of the phase-connected power grid are disconnected from the first branch 201 and the second branch 202. That is, the phase lines Gird_L1 and Gird_L2 of the phase-connected power grid are disconnected from the phase lines Buckup_L1 and Buckup_L2 of the load, and also disconnected from the inverter circuit, allowing the power grid to be in off-grid mode.
[0090] In other embodiments, the grid-connected switch group may further include a third grid-connected switch, which is connected between the third branch 203 and the third grid terminal B3. It should be understood that, under the condition that the switching circuit 103 is connected to the phase grid, the third grid-connected switch can disconnect the neutral wire Gird_N of the phase grid from the third branch 203. That is, based on the fact that the phase wires Gird_L1 and Gird_L2 of the phase grid are disconnected from the phase wires Buckup_L1 and Buckup_L2 of the load, the neutral wire Gird_N of the phase grid is further disconnected from the neutral wire Buckup_N of the load, which is beneficial to further improve the safety and reliability of the system.
[0091] In some embodiments, such as Figure 18As shown, the conversion module 104 includes, but is not limited to, a non-isolation transformer, an isolation transformer, and a coupling transformer. In at least one embodiment, the conversion module 104 is implemented as a two-input, three-output non-isolation transformer, which helps to reduce the size of the switching circuit 103 and lower its manufacturing cost. In at least one embodiment, the conversion module 104 is implemented as a two-input, three-output isolation transformer, which helps to achieve electrical isolation and improve the safety and stability of the system.
[0092] An inverter 101, such as Figure 1 As shown, it includes a power conversion circuit 102 and the aforementioned switching circuit 103, with the output side of the power conversion circuit 102 connected to the input side of the switching circuit 103. It should be understood that the power conversion circuit is suitable for implementation as a single-phase inverter circuit or a split-phase inverter circuit, and the power conversion circuit can be connected to a single-phase power grid or a split-phase power grid, as well as to a single-phase load or a split-phase load, via the switching circuit 103.
[0093] It is worth mentioning that the switching circuit 103 is suitable for connection with existing single-phase inverter circuits or split-phase inverter circuits to form inverter 101. Inverter 101 is suitable for connection with single-phase grid or split-phase grid, as well as with single-phase load or split-phase load, which helps to reduce the manufacturing cost of inverter 101.
[0094] The basic principles, main features, and advantages of this invention have been described above. Those skilled in the art should understand that this invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely principles of the invention. Various changes and modifications can be made without departing from the spirit and scope of the invention, and all such changes and modifications fall within the scope of the invention as claimed. The scope of protection claimed by this invention is defined by the appended claims and their equivalents.
Claims
1. A switching circuit, characterized by, include: An input terminal group, the input terminal group being adapted to be connected to the output side of a single-phase inverter circuit; A power grid terminal assembly, which is adapted to be connected to the input side of a single-phase power grid or a split-phase power grid; A load terminal group, the load terminal group being adapted to be connected to the input side of a single-phase load or a split-phase load, the load terminal group being connected to the input terminal group so that the power grid can supply power to the load; Several branches, said branches being adapted to connect the grid terminal group and the load terminal group accordingly; A conversion module, the conversion module including an input port for connecting to the input terminal group and an output port for connecting to the load terminal group; A changeover switch group is connected between the outlet and the load terminal group to enable or disable the switching module from the load terminal group; the changeover switch group is also configured to enable or disable the outlet from the branch, thereby enabling or disabling the switching module from the load terminal group. An input switch group is configured to connect the input terminal group directly to the grid terminal group and the load terminal group, or to connect the input terminal group and the load terminal group through the conversion module; the input switch group is also configured to connect the input terminal group to the branch, or to the inlet, or to disconnect the switching circuit from the inverter circuit. In the case of a split-phase power grid in off-grid mode, the input terminal group is adapted to be connected to the load terminal group through the conversion module so that the single-phase inverter circuit supplies power to the split-phase load.
2. The switching circuit of claim 1, wherein The input terminal group includes a first input terminal A1 and a second input terminal A2; the input switch group includes a first input switch K1 and a second input switch K2, wherein the first input switch K1 is adapted to switch between neutral, position a1 and position a2, and the second input switch K2 is adapted to switch between neutral, position b1 and position b2; When the first input switch K1 is in position a2 and the second input switch K2 is in position b1, the first input terminal A1 and the second input terminal A2 are adapted to be connected to the input of the conversion module respectively; when the first input switch K1 is in position a1 and the second input switch K2 is in position b2, the first input terminal A1 and the second input terminal A2 are adapted to be directly connected to the power grid terminal group; when the first input switch K1 and the second input switch K2 are in the neutral position, the switching circuit is disconnected from the single-phase inverter circuit.
3. The switching circuit of claim 2, wherein, The input terminal group further includes a third input terminal A3, so that the input side of the switching circuit is adapted to be connected to the output side of a single-phase inverter circuit or a split-phase inverter circuit. The switch group also includes a third input switch K3, which is adapted to switch between an open position and a closed position. By switching the first input switch K1, the second input switch K2 and the third input switch K3, the switching circuit can be connected to or disconnected from the inverter circuit.
4. The switching circuit according to any one of claims 1-3, characterized in that, The switching circuit further includes a motor terminal group and a motor switch group. The motor terminal group is adapted to be connected to a generator, and the motor switch group is connected between the motor terminal group and the input port of the conversion module, so that the motor terminal group can be connected or disconnected from the input side of the conversion module.
5. The switching circuit according to claim 3, characterized in that, The input ports of the conversion module include input ports #1 and #2. When the first input switch K1 is set to position a2 and the second input switch K2 is set to position b1, the first input terminal A1 and the second input terminal A2 can be connected to input ports #1 and #2 respectively. The input outlets include input outlets #3, #4, and #5. The changeover switch group includes a first changeover switch K4, a second changeover switch K5, and a third changeover switch K6, which are adapted to switch between open and closed positions, respectively. The first changeover switch K4, the second changeover switch K5, and the third changeover switch K6 can be connected to input outlets #3, #4, and #5, respectively, so that the conversion module can be connected to or disconnected from the load terminal group.
6. The switching circuit according to any one of claims 1-3, characterized in that, The switching circuit also includes a grid-connected switch group, which is connected between the input switch group and the grid terminal group to enable the grid to switch between off-grid mode and grid-connected mode.
7. The switching circuit according to claim 6, characterized in that, The grid-connected switch group includes a first grid-connected switch K7 and a second grid-connected switch K8, which are adapted to switch between an open position and a closed position, respectively, so as to connect or disconnect the switching circuit from the power grid.
8. The switching circuit according to any one of claims 1-3, characterized in that, The conversion module includes a coupling transformer or an isolation transformer.
9. An inverter, characterized in that, include: The switching circuit as described in any one of claims 1-8; A power conversion circuit, wherein the output side of the power conversion circuit is connected to the input side of the switching circuit.