Alternating current power supply system and alternating current power supply method
Patent Information
- Application Number
- CN202510444881.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-09
- Publication Date
- 2026-10-20
AI Technical Summary
[0004]然而，微型储能系统并不能同时通过并网口以及离网口供电，因此，为了满足关键设备(例如机房数据服务器)不间断供电的要求，用户通常需要为供电系统配备不间断电源(Uninterruptible Power Supply，UPS)，这导致了目前供电系统复杂的问题
[0044]本申请通过逆变模块将直流电源输入的直流电转换为交流电输出，并由交流输出管理模块对逆变模块输出的交流电进行管理，例如，交流输出管理模块可以控制并网端口的端口功率为逆变模块输出功率的50％，并控制离网端口的端口功率为逆变模块输出功率的50％，也就是说，交流输出管理模块可以将逆变模块50％功率的交流电通过并网端口并入电网，并逆变模块50％功率的交流电通过离网端口为负载供电，因此交流输出管理模块不仅可以通过并网端口可以接入电网实现并网，同时通过离网端口还可以接入负载并为负载提供不间断电源。
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Abstract
Description
Technical Field
[0001] This application relates to the field of power supply technology, specifically to an AC power supply system and AC power supply method. Background Technology
[0002] Currently, Micro Energy Storage Systems (MESS) can store excess electricity when there is a surplus of energy production (e.g., during the day when photovoltaic power generation exceeds immediate demand), and then release the stored energy for use when there is a shortage of energy production (e.g., at night or on cloudy days), thereby achieving the purpose of peak shaving and valley filling to balance the grid load.
[0003] In related technologies, micro energy storage systems mainly include photovoltaic panels, energy storage batteries, inverters, and relays for controlling grid connection and off-grid operation. During operation, micro energy storage systems have grid-connected and off-grid modes. In grid-connected mode, the relay controls the inverter's grid connection port to connect to the grid, thereby supplying power to the grid and reducing grid load. In off-grid mode, the relay controls the inverter's off-grid port to connect to the load, ensuring power supply to the load in the event of a grid power outage.
[0004] However, micro energy storage systems cannot be powered simultaneously through both grid-connected and off-grid ports. Therefore, in order to meet the uninterrupted power supply requirements of critical equipment (such as data servers in computer rooms), users usually need to equip the power supply system with an uninterruptible power supply (UPS), which leads to the current complex problems of power supply systems. Summary of the Invention
[0005] This application provides an AC power supply system and an AC power supply method to solve the above-mentioned technical problems.
[0006] In a first aspect, this application provides an AC power supply system, comprising:
[0007] DC power supply;
[0008] The inverter module has its input terminal connected to the output terminal of the DC power supply. The inverter module is used to output AC power based on the DC power input from the DC power supply.
[0009] An AC output management module is connected to the output of the inverter module.
[0010] The AC output management module has a grid-connected port and an off-grid port, and is used to control the port power of the grid-connected port and the off-grid port.
[0011] In some embodiments, when the port power of the off-grid port is less than the rated power of the inverter module, the grid-connected port is configured as a grid-connected output port, and the port power of the grid-connected port is less than or equal to the remaining power.
[0012] When the power of the off-grid port is greater than the rated power of the inverter module, the grid-connected port is configured as the grid-connected input port, and the power of the grid-connected port is equal to the compensation power.
[0013] Among them, the residual power is equal to the difference between the rated power of the inverter module and the port power of the off-grid port, and the compensation power is equal to the difference between the port power of the off-grid port and the rated power of the inverter module.
[0014] In some embodiments, the AC output management module includes a first current control unit;
[0015] The input terminal of the first current control unit is connected to the output terminal of the inverter module, and the output terminal of the first current control unit is connected to the grid connection port.
[0016] The sum of the current at the grid-connected port and the current at the off-grid port is equal to the current output by the inverter module. The first current control unit is used to control the current at the grid-connected port in order to change the current at the off-grid port.
[0017] In some embodiments, the AC output management module includes a second current control unit;
[0018] The input terminal of the second current control unit is connected to the output terminal of the inverter module, and the output terminal of the second current control unit is connected to the off-grid port.
[0019] The sum of the current at the grid-connected port and the current at the off-grid port is equal to the current output by the inverter module. The second current control unit is used to control the current at the off-grid port in order to change the current at the grid-connected port.
[0020] In some embodiments, the first current control unit includes a first switch, a second switch, and a first inductor;
[0021] The first terminal of the first switch is connected to the output terminal of the inverter module, the second terminal of the first switch is connected to the first terminal of the first inductor, and the second terminal of the first inductor is connected to the grid connection port.
[0022] The first end of the second switch is connected to the first node between the first switch and the first inductor, and the second end of the second switch is connected to the ground terminal.
[0023] In some embodiments, the first switch includes a first NMOS transistor and a second NMOS transistor;
[0024] The source of the first NMOS transistor is connected to the output terminal of the inverter module, the drain of the first NMOS transistor is connected to the drain of the second NMOS transistor, and the source of the second NMOS transistor is connected to the grid connection port.
[0025] In some embodiments, the second switch includes a third NMOS transistor and a fourth NMOS transistor;
[0026] The source of the third NMOS transistor is connected to the first node between the first switch and the second switch. The drain of the third NMOS transistor is connected to the drain of the fourth NMOS transistor. The source of the fourth NMOS transistor is connected to the ground terminal.
[0027] Secondly, this application provides an AC power supply method, which is applied to the AC power supply system as described in the first aspect. The AC power supply method includes:
[0028] Obtain the first port power of the off-network port;
[0029] The power of the second port of the grid-connected port is controlled based on the power of the first port and the rated power of the inverter module.
[0030] In some embodiments, when the power of the first port is less than the rated power of the inverter module, the power of the second port of the grid-connected port is less than or equal to the remaining power.
[0031] When the power of the first port is greater than the rated power of the inverter module, the power of the second port of the grid-connected port is equal to the compensation power;
[0032] The remaining power is equal to the difference between the rated power of the inverter module and the power of the first port, and the compensation power is equal to the difference between the power of the first port and the rated power of the inverter module.
[0033] In some embodiments, the step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module includes:
[0034] When the power of the first port is less than the rated power of the inverter module, the remaining power is determined based on the rated power of the inverter module and the power of the first port.
[0035] If the remaining power is less than or equal to the preset grid connection limit power, the power of the second port controlling the grid connection port is equal to the remaining power;
[0036] If the remaining power is greater than the preset grid connection limit power, the power of the second port controlling the grid connection port is equal to the grid connection limit power.
[0037] In some embodiments, the step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module includes:
[0038] Obtain indoor power consumption;
[0039] When the power of the first port is less than the rated power of the inverter module, and the sum of the indoor power consumption and the power of the first port is greater than or equal to the rated power of the inverter module, the remaining power is determined based on the rated power of the inverter module and the power of the first port, and the power of the second port of the grid-connected port is controlled to be equal to the remaining power.
[0040] When the power of the first port is less than the rated power of the inverter module, and the sum of the indoor power consumption and the power of the first port is less than the rated power of the inverter module, the remaining power is determined based on the output power of the inverter module and the power of the first port. If the remaining power is less than or equal to the preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the indoor power consumption; if the remaining power is greater than the preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the grid connection limit power.
[0041] In some embodiments, the step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module further includes:
[0042] When the power of the first port is greater than the rated power of the inverter module but less than the off-grid limit power, the compensation power is determined based on the power of the first port and the rated power of the inverter module, and the power of the second port of the grid-connected port is controlled to be equal to the compensation power.
[0043] When the power of the first port exceeds the off-grid limit, the control inverter module and the AC output management module stop working.
[0044] This application uses an inverter module to convert DC power input into AC power output, and an AC output management module manages the AC power output from the inverter module. For example, the AC output management module can control the port power of the grid-connected port to 50% of the inverter module's output power, and control the port power of the off-grid port to 50% of the inverter module's output power. In other words, the AC output management module can connect 50% of the inverter module's AC power to the grid through the grid-connected port, and supply 50% of the inverter module's AC power to the load through the off-grid port. Therefore, the AC output management module can not only connect to the grid through the grid-connected port to achieve grid connection, but also connect to the load through the off-grid port and provide uninterruptible power to the load.
[0045] In other words, this application uses an AC output management module to replace the traditional grid-connected relay and off-grid relay. Since the AC output management module can manage the port power of the grid-connected port and the off-grid port, the grid-connected port and the off-grid port can work at the same time, thereby realizing the grid connection and uninterrupted power supply functions simultaneously. Compared with the traditional power supply system composed of a micro energy storage system and an uninterruptible power supply, this application can simplify the structure of the power supply system while realizing the grid connection and uninterrupted power supply functions simultaneously. Attached Figure Description
[0046] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0047] Figure 1 This is a schematic diagram of a power supply system in related technologies;
[0048] Figure 2 This is a schematic diagram illustrating an AC power supply system according to an embodiment of this application;
[0049] Figure 3 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0050] Figure 4 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0051] Figure 5 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0052] Figure 6 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0053] Figure 7 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0054] Figure 8 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0055] Figure 9 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0056] Figure 10 This is a schematic diagram illustrating another AC power supply system in an embodiment of this application;
[0057] Figure 11This is a schematic diagram illustrating the first control signal, the second control signal, and the third control signal in an embodiment of this application;
[0058] Figure 12 This is a schematic flowchart illustrating an AC power supply method in an embodiment of this application;
[0059] Figure 13 This is a schematic diagram illustrating a process for controlling the power of the second port in an embodiment of this application;
[0060] Figure 14 This is a schematic diagram illustrating a process for controlling the power of the second port in an embodiment of this application;
[0061] Figure 15 This is a schematic diagram illustrating a process for controlling the power of the second port in an embodiment of this application.
[0062] Among them, 10 is a DC power supply, 11 is a photovoltaic panel, 12 is a first DC-DC converter, 13 is an energy storage battery, 14 is a second DC-DC converter, 15 is an anti-reverse circuit, 20 is an inverter module, 30 is an AC output management module, 301 is a grid-connected port, 302 is an off-grid port, 311 is a first switch, and 312 is a second switch.
[0063] First inductor L1, first capacitor C1, capacitor C0, first node m1, first NMOS transistor M1, second NMOS transistor M2, third NMOS transistor M3, fourth NMOS transistor M4;
[0064] Rated power P, first port power Poff, second port power Pon, remaining power Ps, compensation power Pc, grid-connected limiting power Pon_Lim, off-grid limiting power Poff_Lim, indoor power Phouse. Detailed Implementation
[0065] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0066] In the description of this invention, the term "exemplary" is used to mean "serving as an example, illustration, or description." Any embodiment described as "exemplary" in this application is not necessarily to be construed as being more preferred or advantageous than other embodiments. The following description is provided to enable any person skilled in the art to make and use the invention. Details are set forth in the following description for purposes of explanation. It should be understood that those skilled in the art will recognize that the invention can be made without using these specific details. In other instances, well-known structures and processes will not be described in detail to avoid obscuring the description of the invention with unnecessary detail. Therefore, the invention is not intended to be limited to the embodiments shown, but is consistent with the broadest scope of the principles and features disclosed in this application.
[0067] Micro energy storage systems are a type of energy storage and management system primarily used for miniaturized, distributed energy storage. (See also...) Figure 1 , Figure 1 The diagram illustrates a micro energy storage system in the related art. The micro energy storage system includes a photovoltaic panel, a storage battery, an inverter, a grid-connected relay, and an off-grid relay. The input terminal of the inverter is connected to the output terminals of the photovoltaic panel and the storage battery. The inverter can convert the DC voltage output by the photovoltaic panel and / or the storage battery into AC voltage. One end of the grid-connected relay is connected to the output terminal of the inverter, and the other end is connected to the grid connection port, which is connected to the power grid. Therefore, the grid-connected relay can be used to determine whether the AC voltage output by the inverter is connected to the power grid. One end of the off-grid relay is connected to the output terminal of the inverter, and the other end is connected to the off-grid connection port, which is connected to the load. Therefore, the off-grid relay can be used to supply power to the load using the AC voltage output by the inverter.
[0068] During the operation of the micro energy storage system, the micro energy storage system has a grid-connected operating mode and an off-grid operating mode. In the grid-connected operating mode, the grid-connected relay is closed and the off-grid relay is open, so the AC voltage output by the inverter can be connected to the grid through the grid-connected port. In the off-grid operating mode, the grid-connected relay is open and the off-grid relay is closed, so the AC voltage output by the inverter supplies power to the load through the off-grid port, so as to ensure that the load is powered in the event of a grid power outage.
[0069] However, micro energy storage systems cannot be powered simultaneously through both grid-connected and off-grid ports. Therefore, in order to meet the uninterrupted power supply requirements of critical equipment (such as data servers in computer rooms), users usually need to equip the power supply system with an uninterruptible power supply (UPS), which leads to the current complex problems of power supply systems.
[0070] Therefore, this application provides an AC power supply system and an AC power supply method, which will be described in detail below.
[0071] First, refer to Figure 2 , Figure 2 A schematic diagram of an AC power supply system according to an embodiment of this application is shown, wherein the AC power supply system includes a DC power supply 10, an inverter module 20, and an AC output management module 30.
[0072] Specifically, the DC power supply 10 can output DC power so that the inverter module 20 can convert the DC power output by the DC power supply 10 into AC power output. In some embodiments of this application, the DC power supply 10 may include a power generation device that provides DC power. For example, the DC power supply 10 may include a photovoltaic panel 11, which includes, but is not limited to, photovoltaic panels 11 batteries such as monocrystalline silicon batteries, polycrystalline silicon batteries, and amorphous silicon batteries that can convert solar energy into electrical energy. In some embodiments of this application, the DC power supply 10 may include an energy storage device that provides DC power. For example, the DC power supply 10 may include energy storage batteries 13 such as lead-acid batteries, lithium-ion batteries, sodium-sulfur batteries, nickel-metal hydride batteries, and nickel-cadmium batteries.
[0073] As an exemplary embodiment of the DC power supply 10, see [reference]. Figure 3 , Figure 3 This illustration shows another schematic diagram of the AC power supply system in an embodiment of this application. The DC power supply 10 includes a photovoltaic panel 11, a first DC-DC converter 12, an energy storage battery 13, and a second DC-DC converter 14. The input terminal of the first DC-DC converter 12 is connected to the photovoltaic panel 11, and its output terminal is connected to the input terminal of the inverter module 20. The first DC-DC converter 12 can boost or buck the DC power output from the photovoltaic panel 11, ensuring that the DC voltage provided by the photovoltaic panel 11 meets the DC input voltage requirements of the inverter module 20. The input terminal of the second DC-DC converter 14 is connected to the energy storage battery 13, and its output terminal is connected to the input terminal of the inverter module 20. The second DC-DC converter 14 can boost or buck the DC voltage output from the energy storage battery 13, ensuring that the DC voltage provided by the energy storage battery 13 meets the DC input voltage requirements of the inverter module 20.
[0074] For example, the first DC-DC converter 12 and the second DC-DC converter 14 may include, but are not limited to, a BOOST boost circuit, a BUCK buck circuit, or a BOOST-BUCK buck-boost circuit.
[0075] As another exemplary embodiment of the DC power supply 10, see [reference]. Figure 4 , Figure 4This illustration shows another schematic diagram of the AC power supply system in an embodiment of this application. The DC power supply 10 includes a photovoltaic panel 11, an energy storage battery 13, and an anti-reverse circuit 15. The input terminal of the anti-reverse circuit 15 is connected to the photovoltaic panel 11, and the output terminal of the anti-reverse circuit 15 is connected to the input terminal of the inverter module 20. The DC power output by the photovoltaic panel 11 can charge the energy storage battery 13 through the anti-reverse circuit 15. After the energy storage battery 13 is fully charged, it then provides DC power to the inverter module 20.
[0076] As another exemplary embodiment of the DC power supply 10, see [reference]. Figure 5 , Figure 5 This illustration shows another schematic diagram of the AC power supply system in an embodiment of this application. The DC power supply 10 includes a photovoltaic panel 11, an anti-reverse circuit 15, an energy storage battery 13, and a second DC-DC converter 14. The input terminal of the anti-reverse circuit 15 is connected to the photovoltaic panel 11, and the output terminal of the anti-reverse circuit 15 is connected to the input terminal of the inverter module 20. The input terminal of the second DC-DC converter 14 is connected to the energy storage battery 13, and the output terminal of the second DC-DC converter 14 is connected to the input terminal of the inverter module 20. The DC power output from the photovoltaic panel 11 can charge the energy storage battery 13 via the anti-reverse circuit 15. After the energy storage battery 13 is fully charged, the second DC-DC converter 14 boosts or bucks the DC voltage output from the energy storage battery 13, so that the DC voltage provided by the energy storage battery 13 meets the DC input voltage requirements of the inverter module 20.
[0077] The input terminal of inverter module 20 is connected to the output terminal of DC power supply 10. Inverter module 20 can convert the DC voltage input from DC power supply 10 into AC power (e.g., single-phase AC, three-phase AC, etc.) for output, so that the AC power can be input to AC output management module 30, which manages grid-connected power and off-grid power. Generally, inverter module 20 includes multiple switching transistors (e.g., thyristors, IGBTs, etc.). By controlling the on and off states of the switching transistors, the output voltage waveform is adjusted, thereby realizing DC to AC conversion.
[0078] For example, the inverter module 20 may include, but is not limited to, a half-bridge inverter circuit, a full-bridge inverter circuit, or a push-pull inverter circuit.
[0079] Understandably, in some possible embodiments, the inverter module 20 may also convert the AC power input from the grid into DC power and charge the energy storage battery. For example, the energy storage battery provides DC power to the inverter module 20 during the day, while the inverter module 20 converts the AC power input from the grid into DC power and charges the energy storage battery at night, thereby realizing the function of peak shaving and valley filling of the grid.
[0080] The input terminal of the AC output management module 30 is connected to the output terminal of the inverter module 20. The AC output management module 30 has a grid-connected port 301 and an off-grid port 302. The grid-connected port 301 of the AC output management module 30 can be connected to the power grid, and the off-grid port 302 of the AC output management module 30 can be connected to the load. The AC output management module 30 can manage the port power of the grid-connected port 301 and the off-grid port 302, so that the grid-connected port 301 can output AC power to the power grid or input AC power from the power grid, while the off-grid port 302 can be used as an uninterruptible power supply (UPS) output port for the load.
[0081] It should be noted that port power refers to the power of the AC output / input at the corresponding port. Generally, the power of AC power can be calculated based on the magnitude of AC voltage and AC current. For example, the port power of grid-connected port 301 refers to the power of AC output / input at grid-connected port 301, which can be calculated based on the magnitude of AC voltage and AC current at grid-connected port 301. Similarly, the port power of off-grid port 302 refers to the power of AC output / input at off-grid port 302, which can be calculated based on the magnitude of AC voltage and AC current at off-grid port 302.
[0082] In some embodiments of this application, the AC output management module 30 can control the current of the grid-connected port 301 and / or the off-grid port 302. When the AC voltage amplitude remains constant, it can control the power of the grid-connected port 301 and the off-grid port 302, thereby enabling the current output management module to manage the port power of the grid-connected port 301 and the off-grid port 302. In other embodiments of this application, the AC output management module 30 can control the voltage of the grid-connected port 301 and / or the off-grid port 302. When the AC current amplitude remains constant, it can control the power of the grid-connected port 301 and the off-grid port 302, thereby enabling the current output management module to manage the port power of the grid-connected port 301 and the off-grid port 302.
[0083] In this embodiment, the DC power input from the DC power supply 10 is converted into AC power output by the inverter module 20, and the AC output management module 30 manages the AC power output by the inverter module 20. For example, the AC output management module 30 can control the port power of the grid-connected port 301 to 50% of the output power of the inverter module 20, and control the port power of the off-grid port 302 to 50% of the output power of the inverter module 20. That is, the AC output management module 30 can connect the AC power output by the inverter module 20 to the power grid through the grid-connected port 301, and supply the load with the AC power output by the inverter module 20 through the off-grid port 302. Therefore, the AC output management module 30 can not only connect to the power grid through the grid-connected port 301 to achieve grid connection, but also connect to the load through the off-grid port 302 and provide uninterrupted power to the load.
[0084] In other words, this application uses an AC output management module 30 to replace the traditional grid-connected relay and off-grid relay. Since the AC output management module 30 can manage the port power of the grid-connected port 301 and the off-grid port 302, the grid-connected port 301 and the off-grid port 302 can work simultaneously, thereby realizing both grid connection and uninterrupted power supply to the load. Compared with the traditional power supply system composed of a micro energy storage system and an uninterruptible power supply, this application can simplify the structure of the power supply system while simultaneously realizing both grid connection and uninterrupted power supply functions.
[0085] In some embodiments of this application, when the port power of the off-grid port 302 is less than the rated power of the inverter module 20, the grid-connected port 301 is configured as a grid-connected output port, and the port power of the grid-connected port 301 is less than or equal to the residual power; when the port power of the off-grid port 302 is greater than the rated power of the inverter module 20, the grid-connected port 301 is configured as a grid-connected input port, and the port power of the grid-connected port 301 is equal to the compensation power, wherein the residual power is equal to the difference between the rated power of the inverter module 20 and the port power of the off-grid port 302, and the compensation power is equal to the difference between the port power of the off-grid port 302 and the rated power of the inverter module 20.
[0086] For example, taking the rated power of inverter module 20 as 2000W, if the port power of off-grid port 302 is 1500W, the remaining power is 500W. AC output management module 30 can configure grid-connected port 301 as a grid-connected output port and control its port power to be equal to 500W, thus connecting the remaining 500W of AC power into the grid. If the port power of off-grid port 302 is 2500W, the compensation power is 500W. AC output management module 30 can configure grid-connected port 301 as a grid-connected input port, inputting 500W of AC power from the grid to off-grid port 302, thereby ensuring the power supply to off-grid port 302.
[0087] It can be seen that when the port power of the off-grid port 302 is less than the rated power of the inverter module 20, the AC output management module 30 can input the remaining AC power into the grid, which can not only ensure the normal power supply of the load, but also reduce the load of the grid. When the port power of the off-grid port 302 is greater than the rated power of the inverter module 20, the AC output management module 30 can input AC power as compensation power from the grid, and use the grid and the inverter module to supply power to the load at the same time, thereby ensuring the normal power supply of the load.
[0088] In some embodiments of this application, when the remaining power is less than or equal to the preset grid connection limit power, the AC output management module 30 can control the port power of the grid connection port 301 to be equal to the remaining power; when the remaining power is greater than the preset grid connection limit power, the AC output management module 30 can control the port power of the grid connection port 301 to be equal to the grid connection limit power.
[0089] It should be noted that the grid connection limit power refers to the port power limit value of the grid connection port 301. In different regions, the grid connection limit power is determined according to local regulations. The grid connection limit power can limit the power connected to the grid through the grid connection port 301 to prevent the phenomenon of excessive AC power being connected to the grid.
[0090] For example, taking an inverter module 20 with a rated power of 2000W and a grid-connected power limit of 800W, if the power of the off-grid port 302 is 1600W, the remaining power is 400W. Since the remaining power is less than the grid-connected power limit, the AC output management module 30 can control the power of the grid-connected port 301 to equal the remaining power of 400W, thus connecting the remaining 400W of AC power into the grid. If the power of the off-grid port 302 is 1100W, the remaining power is 900W. Since the remaining power exceeds the grid-connected power limit, the AC output management module 30 can control the power of the grid-connected port 301 to equal 800W, thus connecting the remaining 800W of AC power into the grid and changing the operating mode of the inverter module 20 to constant voltage mode, so that the inverter module 20 no longer outputs at the rated power of 2000W, but outputs AC power at 1900W.
[0091] As can be seen, the AC output management module 30 of this application can not only allocate port power to the grid-connected port 301 and the off-grid port 302, but also limit the output power of the grid-connected port 301 to prevent excessive AC power from being connected to the grid.
[0092] In some embodiments of this application, see Figure 6 , Figure 6 This paper shows another schematic diagram of an AC power supply system in an embodiment of the present application, wherein the AC output management module 30 includes a first current control unit 31; the input terminal of the first current control unit 31 is connected to the output terminal of the inverter module 20, and the output terminal of the first current control unit 31 is connected to the grid connection port 301.
[0093] It should be noted that the first current control unit 31 can control the current magnitude of the grid-connected port 301. Since the sum of the current of the grid-connected port 301 and the current of the off-grid port 302 equals the current output by the inverter module 20, the first current control unit 31 can indirectly control the current magnitude of the off-grid port 302. For example, when the first current control unit 31 decreases the current of the grid-connected port 301, it can increase the current of the off-grid port 302. With the amplitude of the output AC voltage remaining unchanged, this is equivalent to decreasing the port power of the grid-connected port 301 while increasing the port power of the off-grid port 302. Conversely, when the first current control unit 31 increases the current of the grid-connected port 301, it can decrease the current of the off-grid port 302. With the amplitude of the output AC voltage remaining unchanged, this is equivalent to increasing the port power of the grid-connected port 301 while decreasing the port power of the off-grid port 302.
[0094] As can be seen, the AC output management module 30 controls the current of the grid-connected port 301 by setting the first current control unit 31 at the grid-connected port 301, thereby achieving the purpose of controlling the port power of the grid-connected port 301 and the off-grid port 302.
[0095] In some embodiments of this application, see Figure 7 , Figure 7 This paper shows another schematic diagram of an AC power supply system in an embodiment of this application, wherein the AC output management module 30 includes a second current control unit 32; the input terminal of the second current control unit 32 is connected to the output terminal of the inverter module 20, and the output terminal of the second current control unit 32 is connected to the off-grid port 302.
[0096] It should be noted that the second current control unit 32 can control the current magnitude of the off-grid port 302. Since the sum of the current of the grid-connected port 301 and the current of the off-grid port 302 equals the current output by the inverter module 20, the second current control unit 32 can indirectly control the current magnitude of the grid-connected port 301. For example, when the second current control unit 32 decreases the current of the off-grid port 302, it can increase the current of the grid-connected port 301. With the amplitude of the output AC voltage remaining unchanged, this is equivalent to decreasing the port power of the off-grid port 302 while increasing the port power of the grid-connected port 301. Conversely, when the second current control unit 32 increases the current of the off-grid port 302, it can decrease the current of the grid-connected port 301. With the amplitude of the output AC voltage remaining unchanged, this is equivalent to increasing the port power of the off-grid port 302 while decreasing the port power of the grid-connected port 301.
[0097] It can be seen that the AC output management module 30 controls the current of the off-grid port 302 through the second current control unit 32 set at the off-grid port 302, and can also achieve the purpose of controlling the port power of the grid-connected port 301 and the off-grid port 302.
[0098] It should be noted that in some possible embodiments, the AC output management module 30 may also include both a first current control unit 31 and a second current control unit 32, for example, see [reference]. Figure 8 , Figure 8 This illustration shows another schematic diagram of an AC power supply system in an embodiment of this application. The AC output management module 30 includes a first current control unit 31 and a second current control unit 32. The AC output management module 30 controls the current magnitude of the grid-connected port 301 and the off-grid port 302 respectively by setting the first current control unit 31 at the grid-connected port 301 and setting the second current control unit 32 at the off-grid port 302. This can also achieve the purpose of controlling the port power of the grid-connected port 301 and the off-grid port 302.
[0099] In some embodiments of this application, see Figure 9 , Figure 9 A schematic diagram of a first current control unit 31 in an embodiment of this application is shown. The first current control unit 31 includes a first switch 311, a second switch 312, and a first inductor L1. The first terminal of the first switch 311 is connected to the output terminal of the inverter module 20, and the second terminal of the first switch 311 is connected to the first terminal of the first inductor L1. The second terminal of the first inductor L1 is connected to the grid-connected port 301. The first terminal of the second switch 312 is connected to a first node m1 between the first switch 311 and the first inductor L1, and the second terminal of the second switch 312 is connected to the ground terminal. It should be noted that the first switch 311 and the second switch 312 can be sinusoidally controlled by the AC current at the off-grid port 302. Due to the characteristic that the first inductor L1 passes DC and blocks AC, by controlling the closing and opening times of the first switch 311 and the second switch 312, the current flowing through the first inductor L1 and the power at the grid-connected port 301 can be controlled, ultimately achieving the purpose of controlling the port power of the off-grid port 302.
[0100] Understandably, such as Figure 9 As shown, the first current control unit 31 may also include a capacitor C0 connected between the output terminal and the ground terminal of the inverter module 20, and a capacitor C1 connected between the grid connection port 301 and the ground terminal. The capacitors C0 and C1 serve as energy storage elements in the circuit to ensure the smoothness of the AC power.
[0101] In some embodiments of this application, see Figure 10 , Figure 10 Another schematic diagram of the first current control unit 31 in this application embodiment is shown, wherein the first switch 311 includes a first NMOS transistor M1 and a second NMOS transistor M2; the source of the first NMOS transistor M1 is connected to the output terminal of the inverter module 20, the drain of the first NMOS transistor M1 is connected to the drain of the second NMOS transistor M2, and the source of the second NMOS transistor M2 is connected to the grid connection port 301.
[0102] It should be noted that since the drains of the first NMOS transistor M1 and the second NMOS transistor M2 are interconnected, the conduction directions of the body diodes of the first NMOS transistor M1 and the second NMOS transistor M2 are opposite. The body diode of the first NMOS transistor M1 can prevent the current from the grid-connected port 301 from flowing to the output terminal of the inverter module 20, and the body diode of the second NMOS transistor M2 can prevent the current from the output terminal of the inverter module 20 from flowing to the grid-connected port 301. Therefore, when the first NMOS transistor M1 and the second NMOS transistor M2 are turned off, the phenomenon of unidirectional current in the off state of either the first NMOS transistor M1 or the second NMOS transistor M2 is avoided.
[0103] In some embodiments of this application, see further reference. Figure 10 The second switch 312 includes a third NMOS transistor M3 and a fourth NMOS transistor M4. The source of the third NMOS transistor M3 is connected to the first node m1 between the first switch 311 and the second switch 312, the drain of the third NMOS transistor M3 is connected to the drain of the fourth NMOS transistor M4, and the source of the fourth NMOS transistor M4 is connected to the ground terminal. Similarly, since the drains of the third NMOS transistor M3 and the fourth NMOS transistor M4 are interconnected, the conduction directions of the body diodes of the third NMOS transistor M3 and the fourth NMOS transistor M4 are opposite. The body diode of the fourth NMOS transistor M4 can prevent the current from flowing from the first node m1 to the ground terminal, and the body diode of the third NMOS transistor M3 can prevent the current from flowing from the ground terminal to the first node m1, thereby avoiding the phenomenon of unidirectional current when the third NMOS transistor M3 or the fourth NMOS transistor M4 is turned off.
[0104] It should be noted that the first current control unit 31 in the above embodiment, by employing the first NMOS transistor M1, the second NMOS transistor M2, the third NMOS transistor M3, and the fourth NMOS transistor M4, can not only control the current flowing through the first inductor L1 through the first NMOS transistor M1, the second NMOS transistor M2, the third NMOS transistor M3, and the fourth NMOS transistor M4, and not only control the port power of the grid-connected port 301 and the off-grid port 302 by controlling the current, but also use the first NMOS transistor M1, the second NMOS transistor M2, the third NMOS transistor M3, and the fourth NMOS transistor M4 as switches to control the disconnection of the AC power supply system from the power grid. For example, when an abnormal grid voltage is detected, controlling the first NMOS transistor M1, the second NMOS transistor M2, the third NMOS transistor M3, and the fourth NMOS transistor M4 to turn off can achieve the function of disconnecting the power grid. Compared with the power supply system in conventional applications where relays are used as disconnecting switches, this application is advantageous in avoiding the problems of arcing and delayed turn-off that exist with relays.
[0105] In some embodiments of this application, see Figure 10 The gates of the first NMOS transistor M1 and the second NMOS transistor M2 can be connected to the first control signal, the gate of the fourth NMOS transistor M4 can be connected to the second control signal, and the third NMOS transistor M3 can be connected to the third control signal.
[0106] Specifically, see Figure 11 , Figure 11 This diagram illustrates a first control signal, a second control signal, and a third control signal in an embodiment of this application. During the positive half-cycle of the alternating current, the third control signal is at a high level, controlling the third NMOS transistor M3 to remain in the on state. The first and second control signals respectively control the first NMOS transistor M1 and the second NMOS transistor M2 to conduct complementaryly with the fourth NMOS transistor M4. The dead time between the first NMOS transistor M1, the second NMOS transistor M2, and the fourth NMOS transistor is t. delay .
[0107] Since the first NMOS transistor M1, the second NMOS transistor M2, and the fourth NMOS transistor M4 are complementary in conducting during the positive half-cycle of the AC current, when the first NMOS transistor M1 and the second NMOS transistor M2 are conducting, the fourth NMOS transistor M4 is turned off. At this time, the first node m1 is connected to the output terminal of the inverter module 20, and the path between the first node m1 and the ground terminal is broken, and the first inductor L1 is charged. When the first NMOS transistor M1 and the second NMOS transistor M2 are turned off, the fourth NMOS transistor M4 is conducted. At this time, the path between the first node m1 and the output terminal of the inverter module 20 is broken, and the first node m1 is connected to the ground terminal, and the first inductor L1 generates an induced electromotive force to discharge. Due to the characteristic of the first inductor L1 to pass DC and block AC, the current of the grid-connected port 301 can be reduced during the positive half-cycle of the AC current, thereby reducing the power of the grid-connected port 301.
[0108] During the negative half-cycle of the AC voltage, the second control signal is high, and the fourth NMOS transistor M4 remains in the on state. The first and third control signals respectively control the first NMOS transistor M1, the second NMOS transistor M2, and the third NMOS transistor M3 to conduct complementaryly. The dead time between the conduction of the first NMOS transistor M1, the second NMOS transistor M2, and the third NMOS transistor is t. delay .
[0109] Since the first NMOS transistor M1, the second NMOS transistor M2, and the third NMOS transistor M3 are complementary in conducting during the negative half-cycle of the AC voltage, when the first NMOS transistor M1 and the second NMOS transistor M2 are turned off, the third NMOS transistor M3 is turned on. At this time, the path between the first node m1 and the output terminal of the inverter module 20 is broken, and the path between the first node m1 and the ground terminal is connected. Since it is the negative half-cycle of the AC power, the first inductor L1 is charged through the ground terminal. When the first NMOS transistor M1 and the second NMOS transistor M2 are turned on, the fourth NMOS transistor M4 is turned off. At this time, the path between the first node m1 and the output terminal of the inverter module 20 is connected, and the first node m1 is disconnected from the ground terminal. The first inductor L1 generates an induced electromotive force and discharges. Due to the characteristic of the first inductor L1 to pass DC and block AC, the current of the grid-connected port 301 can be reduced during the negative half-cycle of the AC power, thereby reducing the power of the grid-connected port 301.
[0110] It should be noted that the above embodiment takes the grid-connected port 301 as the grid-connected output port to output AC power to the circuit as an example to illustrate how to control the port power of the grid-connected port 301. When the grid-connected port 301 is connected to the grid AC power as the grid-connected input port, the first NMOS transistor M1 and the second NMOS transistor M2 can be directly controlled to be turned on, and the third NMOS transistor M3 and the fourth NMOS transistor M4 can be controlled to be turned off.
[0111] Furthermore, to better implement the AC power supply system in the embodiments of this application, this application also provides an AC power supply method based on the AC power supply system. The AC power supply method can be applied to the AC power supply system described in any of the above embodiments. (See reference...) Figure 12 , Figure 12 This paper illustrates a flowchart of an AC power supply method according to an embodiment of the present application, wherein the AC power supply method includes:
[0112] Step S1201: Obtain the first port power Poff of the off-grid port 302;
[0113] Step S1202: Based on the first port power Poff and the rated power P of the inverter module 20, control the second port power Pon of the grid-connected port 301.
[0114] Specifically, the first port power Poff of the off-grid port 302 can be calculated by measuring the voltage and / or current. For example, when the amplitude of the AC voltage output by the off-grid port 302 remains constant, the first port power Poff of the off-grid port 302 can be calculated by measuring the current of the off-grid port 302 using a current sensor; or, for another example, when the amplitude of the AC current output by the off-grid port 302 remains constant, the first port power Poff of the off-grid port 302 can be calculated by measuring the voltage of the off-grid port 302 using a voltage sensor.
[0115] After obtaining the first port power Poff, the second port power Pon of the grid-connected port 301 can be controlled by combining the rated power P of the inverter module 20. For example, assuming the inverter module 20 outputs AC power at its rated power P of 2000W, if the first port power Poff is 1500W, the second port power Pon of the grid-connected port 301 can be controlled to be 500W. As another example, assuming the inverter module 20 outputs AC power at its rated power P of 1800W, if the first port power Poff is 1500W, the second port power Pon of the grid-connected port 301 can be controlled to be 300W. This application controls the port power of both the grid-connected port 301 and the off-grid port 302, thus simultaneously achieving grid connection and uninterrupted power supply to the load. Compared to traditional power supply systems composed of micro-energy storage systems and uninterruptible power supplies, this application simplifies the power supply system structure while simultaneously achieving grid connection and uninterrupted power supply functions.
[0116] In some embodiments of this application, when the first port power Poff is less than the rated power P of the inverter module 20, the second port power Pon of the grid-connected port 301 is less than or equal to the residual power Ps; when the first port power Poff is greater than the rated power P of the inverter module 20, the second port power Pon of the grid-connected port 301 is equal to the compensation power Pc; wherein, the residual power Ps is equal to the difference between the rated power P of the inverter module 20 and the first port power Poff, and the compensation power Pc is equal to the difference between the first port power Poff and the rated power P of the inverter module 20.
[0117] For example, taking the rated power P of inverter module 20 as 2000W, if the power Poff of the first port of off-grid port 302 is 1500W, and the remaining power Ps is 500W, AC output management module 30 can configure grid-connected port 301 as a grid-connected output port and control the power Pon of the second port of grid-connected port 301 to be equal to 500W, thereby connecting the remaining 500W of AC power into the grid. If the power Poff of the first port of off-grid port 302 is 2500W, and the compensation power Pc is 500W, AC output management module 30 can configure grid-connected port 301 as a grid-connected input port, inputting 500W of AC power from the grid to off-grid port 302, thereby ensuring the power supply to off-grid port 302.
[0118] It can be seen that when the power Poff of the first port of the off-grid port 302 is less than the rated power P of the inverter module 20, the AC output management module 30 can input the remaining power Ps of AC power into the grid, which can not only ensure the normal power supply of the load, but also reduce the load of the grid. When the power Poff of the first port of the off-grid port 302 is greater than the rated power P of the inverter module 20, the AC output management module 30 can input AC power as compensation power Pc from the grid, and use the grid and the inverter module 20 to supply power to the load at the same time, thereby ensuring the normal power supply of the load.
[0119] In some embodiments of this application, see Figure 13 , Figure 13 This paper illustrates a flowchart of controlling the power Pon of the second port in an embodiment of this application. The steps for controlling the power Pon of the second port of the grid-connected port 301 based on the power Poff of the first port and the rated power P of the inverter module 20 include:
[0120] Step S1301: When the power Poff at the first port is less than the rated power P of the inverter module 20, the remaining power Ps is determined based on the rated power P of the inverter module 20 and the power Poff at the first port.
[0121] Step S1302: If the remaining power Ps is less than or equal to the preset grid connection limit power Pon_Lim, control the second port power Pon of the grid connection port 301 to be equal to the remaining power Ps.
[0122] Step S1303: When the remaining power Ps is greater than the preset grid connection limit power Pon_Lim, the power Pon of the second port of the grid connection port 301 is controlled to be equal to the grid connection limit power Pon_Lim.
[0123] For example, taking inverter module 20 with a rated power P of 2000W and a grid-connected power limit Pon_Lim of 800W as an example, if the power Poff of the first port of off-grid port 302 is 1600W, the remaining power Ps is 400W. Since the remaining power Ps is less than the grid-connected power limit Pon_Lim, the power Pon of the second port of grid-connected port 301 can be controlled to be equal to 400W, thereby connecting the remaining 400W of AC power into the grid. If the power Poff of the first port of off-grid port 302 is 1100W, the remaining power Ps is 900W. Since the remaining power Ps exceeds the grid-connected power limit Pon_Lim, the power Pon of the second port of grid-connected port 301 can be controlled to be equal to 800W, thereby connecting the remaining 800W of AC power into the grid.
[0124] As can be seen, this application can not only realize the port power allocation of the grid-connected port 301 and the off-grid port 302, but also limit the output power of the grid-connected port 301 to prevent the phenomenon of excessively high power AC power from being connected to the grid.
[0125] In some embodiments of this application, see Figure 14 , Figure 14 This paper illustrates another flowchart of controlling the power Pon of the second port in an embodiment of this application. The steps for controlling the power Pon of the second port of the grid-connected port 301 based on the power Poff of the first port and the rated power P of the inverter module 20 include:
[0126] Step S1401: Obtain the indoor power consumption Phouse;
[0127] Step S1402: When the power Poff of the first port is less than the rated power P of the inverter module 20, and the sum of the indoor power Phouse and the power Poff of the first port is greater than or equal to the rated power P of the inverter module 20, the remaining power Ps is determined according to the rated power P of the inverter module 20 and the power Poff of the first port, and the power Pon of the second port of the grid-connected port 301 is controlled to be equal to the remaining power Ps.
[0128] Step S1402: When the power Poff of the first port is less than the rated power P of the inverter module 20, and the sum of the indoor power Phouse and the power Poff of the first port is less than the rated power P of the inverter module 20, the remaining power Ps is determined based on the output power of the inverter module 20 and the power Poff of the first port. If the remaining power Ps is less than or equal to the preset grid connection limit power Pon_Lim, the power Pon of the second port of the grid connection port 301 is controlled to be equal to the indoor power Phouse; if the remaining power Ps is greater than the preset grid connection limit power Pon_Lim, the power Pon of the second port of the grid connection port 301 is controlled to be equal to the grid connection limit power Pon_Lim.
[0129] It should be noted that the indoor power consumption Phouse can be calculated by measuring it with sensors (such as current sensors and voltage sensors), or it can be calculated by the power of the corresponding port. For example, the indoor power consumption Phouse can be calculated using the output power of the meter box and the power Pon of the second port according to the following formula:
[0130] Phouse = Pg - Pon
[0131] Where Pg is the output power of the meter box, and Pon is the power of the second port.
[0132] In the above embodiment, after obtaining the indoor power consumption Phouse, the power Pon of the second port of the grid-connected port 301 can be controlled in conjunction with the indoor power consumption Phouse. For example, taking the rated power P of the inverter module 20 as 2000W and the grid-connected limiting power Pon_Lim as 800W, if the power Poff of the first port of the off-grid port 302 is 1600W and the indoor power consumption Phouse is 800W, since the power Poff of the first port is less than the rated power P of the inverter module 20, and the sum of the indoor power consumption Phouse and the power Poff of the first port is greater than the rated power P of the inverter module 20, the inverter module 20 can be controlled to output AC power at the rated power P, and the remaining power Ps is determined to be 400W based on the rated power P of the inverter module 20 and the power Poff of the first port, thereby controlling the power Pon of the second port of the grid-connected port 301 to be equal to the remaining power Ps 400W.
[0133] If the first port power Poff of the off-grid port 302 is 1300W and the indoor power Phouse is 400W, since the first port power Poff is less than the rated power P of the inverter module 20, and the sum of the indoor power Phouse and the first port power Poff is less than the rated power P of the inverter module 20, the inverter module 20 can be controlled to output 1700W AC power in constant voltage mode. Based on the output power of the inverter module 20 and the first port power Poff, the remaining power Ps is determined to be 400W. At this time, the remaining power Ps is less than or equal to the preset grid-connected limit power Pon_Lim. Therefore, the second port power Pon of the grid-connected port 301 can be controlled to be equal to 400W.
[0134] If the first port power Poff of the off-grid port 302 is 1100W and the indoor power Phouse is 850W, since the first port power Poff is less than the rated power P of the inverter module 20, and the sum of the indoor power Phouse and the first port power Poff is less than the rated power P of the inverter module 20, the inverter module 20 can be controlled to output 1950W AC power in constant voltage mode. Therefore, the remaining power Ps is determined to be 850W based on the output power of the inverter module 20 and the first port power Poff. At this time, the remaining power Ps is greater than the preset grid connection limit power Pon_Lim, so the second port power Pon of the grid connection port 301 is controlled to be equal to 800W.
[0135] In some embodiments of this application, see Figure 15 , Figure 15 This paper illustrates another flowchart of controlling the power Pon of the second port in an embodiment of this application. The step of controlling the power Pon of the second port of the grid-connected port 301 based on the power Poff of the first port and the rated power P of the inverter module 20 further includes:
[0136] Step S1501: When the first port power Poff is greater than the rated power P of the inverter module 20 and less than the off-grid limit power Poff_Lim, the compensation power Pc is determined according to the first port power Poff and the rated power P of the inverter module 20, and the second port power Pon of the grid-connected port 301 is controlled to be equal to the compensation power Pc.
[0137] Step S1502: When the power Poff of the first port is greater than the off-grid limit power Poff_Lim, control the inverter module 20 and the AC output management module 30 to stop working.
[0138] It should be noted that the off-grid limit power Poff_Lim refers to the maximum output power of the off-grid port 302. If the first port power Poff is greater than the off-grid limit power Poff_Lim, it indicates that there is a load overload or a short circuit in the off-grid port 302. Therefore, when the first port power Poff is greater than the off-grid limit power Poff_Lim, the inverter module 20 and the AC output management module 30 can be controlled to stop to protect the AC management system. When the first port power Poff is greater than the rated power P of the inverter module 20 but less than the off-grid limit power Poff_Lim, it indicates that there is no abnormality in the off-grid port 302. The AC output management module 30 uses AC power input from the grid as compensation power Pc to simultaneously supply power to the load through the grid and the inverter module 20, thereby ensuring normal power supply to the load.
[0139] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the detailed descriptions of other embodiments above, which will not be repeated here.
[0140] The basic concepts have been described above. Obviously, for those skilled in the art, the detailed disclosure above is merely illustrative and does not constitute a limitation of this application. Although not explicitly stated herein, those skilled in the art may make various modifications, improvements, and corrections to this application. Such modifications, improvements, and corrections are suggested in this application, and therefore remain within the spirit and scope of the exemplary embodiments of this application.
[0141] The AC power supply system and AC power supply method provided in the embodiments of this application have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.
Claims
1. An AC power supply system, characterized in that, include: DC power supply; An inverter module, the input terminal of which is connected to the output terminal of the DC power supply, is used to output AC power according to the DC power input from the DC power supply; An AC output management module, wherein the input terminal of the AC output management module is connected to the output terminal of the inverter module; The AC output management module has a grid-connected port and an off-grid port, and is used to control the port power of the grid-connected port and the off-grid port.
2. The AC power supply system as described in claim 1, characterized in that, When the power of the off-grid port is less than the rated power of the inverter module, the grid-connected port is configured as a grid-connected output port, and the power of the grid-connected port is less than or equal to the remaining power. When the power of the off-grid port is greater than the rated power of the inverter module, the grid-connected port is configured as a grid-connected input port, and the power of the grid-connected port is equal to the compensation power. Wherein, the remaining power is equal to the difference between the rated power of the inverter module and the port power of the off-grid port, and the compensation power is equal to the difference between the port power of the off-grid port and the rated power of the inverter module.
3. The AC power supply system as described in claim 1, characterized in that, The AC output management module includes a first current control unit; The input terminal of the first current control unit is connected to the output terminal of the inverter module, and the output terminal of the first current control unit is connected to the grid connection port; Wherein, the sum of the current at the grid-connected port and the current at the off-grid port is equal to the current output by the inverter module, and the first current control unit is used to control the current magnitude at the grid-connected port to change the current magnitude at the off-grid port.
4. The AC power supply system as described in claim 1, characterized in that, The AC output management module includes a second current control unit; The input terminal of the second current control unit is connected to the output terminal of the inverter module, and the output terminal of the second current control unit is connected to the off-grid port; Wherein, the sum of the current at the grid-connected port and the current at the off-grid port is equal to the current output by the inverter module, and the second current control unit is used to control the magnitude of the current at the off-grid port in order to change the magnitude of the current at the grid-connected port.
5. The AC power supply system as described in claim 3, characterized in that, The first current control unit includes a first switch, a second switch, and a first inductor; The first end of the first switch is connected to the output end of the inverter module, the second end of the first switch is connected to the first end of the first inductor, and the second end of the first inductor is connected to the grid connection port. The first end of the second switch is connected to the first node between the first switch and the first inductor, and the second end of the second switch is connected to the ground terminal.
6. The AC power supply system as described in claim 5, characterized in that, The first switch includes a first NMOS transistor and a second NMOS transistor; The source of the first NMOS transistor is connected to the output terminal of the inverter module, the drain of the first NMOS transistor is connected to the drain of the second NMOS transistor, and the source of the second NMOS transistor is connected to the grid-connected port.
7. The AC power supply system as described in claim 5, characterized in that, The second switch includes a third NMOS transistor and a fourth NMOS transistor; The source of the third NMOS transistor is connected to the first node between the first switch and the second switch, the drain of the third NMOS transistor is connected to the drain of the fourth NMOS transistor, and the source of the fourth NMOS transistor is connected to the ground terminal.
8. An AC power supply method, characterized in that, The AC power supply method is applied to the AC power supply system as described in any one of claims 1 to 7, wherein the AC power supply method comprises: Obtain the first port power of the off-network port; The power of the second port of the grid-connected port is controlled based on the power of the first port and the rated power of the inverter module.
9. The AC power supply method as described in claim 8, characterized in that, When the power of the first port is less than the rated power of the inverter module, the power of the second port of the grid-connected port is less than or equal to the remaining power; When the power of the first port is greater than the rated power of the inverter module, the power of the second port of the grid-connected port is equal to the compensation power; Wherein, the remaining power is equal to the difference between the rated power of the inverter module and the power of the first port, and the compensation power is equal to the difference between the power of the first port and the rated power of the inverter module.
10. The AC power supply method as described in claim 8, characterized in that, The step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module includes: When the power of the first port is less than the rated power of the inverter module, the remaining power is determined based on the rated power of the inverter module and the power of the first port. If the remaining power is less than or equal to the preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the remaining power; If the remaining power is greater than the preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the grid connection limit power.
11. The AC power supply method as described in claim 8, characterized in that, The step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module includes: Obtain indoor power consumption; When the power of the first port is less than the rated power of the inverter module, and the sum of the indoor power consumption and the power of the first port is greater than or equal to the rated power of the inverter module, the remaining power is determined according to the rated power of the inverter module and the power of the first port, and the power of the second port of the grid-connected port is controlled to be equal to the remaining power. When the power of the first port is less than the rated power of the inverter module, and the sum of the indoor power consumption and the power of the first port is less than the rated power of the inverter module, the remaining power is determined based on the output power of the inverter module and the power of the first port. If the remaining power is less than or equal to a preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the indoor power consumption; if the remaining power is greater than the preset grid connection limit power, the power of the second port of the grid connection port is controlled to be equal to the grid connection limit power.
12. The AC power supply method as described in claim 10 or 11, characterized in that, The step of controlling the power of the second port of the grid-connected port based on the power of the first port and the rated power of the inverter module further includes: When the power of the first port is greater than the rated power of the inverter module and less than the off-grid limit power, the compensation power is determined based on the power of the first port and the rated power of the inverter module, and the power of the second port of the grid-connected port is controlled to be equal to the compensation power. When the power of the first port exceeds the off-grid limit power, the inverter module and the AC output management module are controlled to stop working.