A parallel connection accessory, an energy storage inverter, and a parallel connection method for an energy storage inverter

Abstract

The present invention discloses a parallel connection accessory, an energy storage inverter, and a parallel connection method for an energy storage inverter. A parallel connection accessory, the parallel connection accessory includes a parallel connection main body, and a standby module, a power output interface, and a parallel connection interface are provided on the parallel connection main body; the number of parallel connection interfaces is multiple, and the parallel connection interfaces include an in-position signal connection terminal, a communication signal connection terminal, and an AC output connection terminal for respectively connecting in one-to-one correspondence with the in-position signal line, communication bus, and AC output line of the energy storage inverter. The standby module is configured to output a standby signal to the energy storage inverter when the energy storage inverter is connected to the parallel connection port, so that the energy storage inverter enters a standby state; the communication signal connection terminals of the multiple parallel connection interfaces are all electrically connected, and are used for enabling multiple energy storage inverters to communicate and detecting the level signals of the amplitude, phase, and frequency required for parallel connection to judge the synchronization information. By adopting the above solution, the problem that the energy storage inverter will malfunction or report an error after parallel connection when there is an existing AC output is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of parallel connection of energy storage inverters, and particularly to a parallel connection accessory, an energy storage inverter, and a parallel connection method for energy storage inverters. Background Art

[0002] Portable energy storage inverters provide energy to electrical appliances through AC output. In actual use, multiple portable energy storage inverters can be used by connecting their AC outputs in parallel to increase the AC output power and battery life.

[0003] For multiple portable energy storage inverters with parallel connection functions, if a user tries to connect them in parallel when one of the portable energy storage inverters already has an AC output, problems such as out-of-sync phases and amplitudes of the AC output lines of each portable energy storage inverter may cause the energy storage inverter to malfunction or report an error. Summary of the Invention

[0004] The present invention provides a parallel connection accessory, an energy storage inverter, and a parallel connection method for energy storage inverters to solve the problem that the energy storage inverter malfunctions or reports an error after parallel connection when there is already an AC output.

[0005] According to one aspect of the present invention, a parallel connection accessory for parallel connection of multiple energy storage inverters is provided. The energy storage inverter includes a connection wire harness, and the connection wire harness includes an in-position signal line, a communication bus, and an AC output line; the parallel connection accessory includes a parallel connection main body, and the parallel connection main body is provided with a standby module, a power output interface, and a parallel connection interface;

[0006] The number of the parallel connection interfaces is multiple, and the parallel connection interfaces are used to be respectively connected to the connection wire harnesses of the multiple energy storage inverters in one-to-one correspondence;

[0007] The parallel connection interface includes an in-position signal connection terminal, a communication signal connection terminal, and an AC output connection terminal, and the in-position signal connection terminal, the communication signal connection terminal, and the AC output connection terminal are used to be respectively connected to the in-position signal line, the communication bus, and the AC output line in one-to-one correspondence;

[0008] The standby module is electrically connected to the in-position signal connection terminal and is used to output a standby signal to the in-position signal line of the energy storage inverter when the energy storage inverter is connected to the parallel connection port, so that the energy storage inverter enters a standby state;

[0009] The communication signal connection terminals of the multiple parallel connection interfaces are all electrically connected and are used to enable communication between the multiple energy storage inverters when the energy storage inverters are connected to the parallel connection port, detect the level signals of amplitude, phase, and frequency required for parallel connection to judge the synchronization information, and synchronously perform AC output through the AC output line based on the synchronization information.

[0010] The AC output connection terminals of the multiple parallel connection interfaces are electrically connected to the power output interface, and the power output interface is used to connect an electrical appliance.

[0011] In an alternative embodiment of the present invention, the standby signal is a low-level signal.

[0012] In an alternative embodiment of the present invention, the energy storage inverter includes a signal ground wire, and the parallel connection interface further includes a signal ground connection terminal, and the signal ground connection terminal is used to connect the signal ground wire of the energy storage inverter;

[0013] One end of the standby module is connected to the signal ground connection terminal, and the other end is connected to the in-position signal connection terminal. The standby module is used to electrically connect the signal ground connection terminal and the in-position signal connection terminal.

[0014] In an alternative embodiment of the present invention, the standby module includes at least one of a metal wire, a mechanical switch, a relay switch, a semiconductor switch, and a digital signal control switch.

[0015] In an alternative embodiment of the present invention, the parallel connection main body includes a parallel connection box. The number of the parallel connection interfaces is two, and the two parallel connection interfaces are respectively arranged on the opposite first side and second side of the parallel connection box. The power output interface is arranged on the third side of the parallel connection box, and the third side is perpendicular to the first side.

[0016] According to another aspect of the present invention, there is provided an energy storage inverter, which includes a control module and a connection wire harness. The connection wire harness includes an in-position signal wire, a communication bus, and an AC output wire;

[0017] The control module is electrically connected to both the communication bus and the in-position signal wire. The control module is used to obtain a standby signal through the in-position signal wire, and is in a standby state when the standby signal is obtained, and communicate with another energy storage inverter through the communication bus, detect the level signals of the amplitude, phase, and frequency required for parallel connection of the two to judge the synchronization information, and synchronously perform AC output through the AC output wire based on the synchronization information.

[0018] In an alternative embodiment of the present invention, the communication bus is a CAN bus.

[0019] In an alternative embodiment of the present invention, the control module is an MCU.

[0020] In an alternative embodiment of the present invention, the standby signal is a low-level signal.

[0021] According to another aspect of the present invention, there is provided a method for paralleling energy storage inverters, including:

[0022] Connect the connection harnesses of multiple energy storage inverters to the multiple parallel connection interfaces of the parallel connection accessory one by one;

[0023] The parallel connection accessory outputs a standby signal to the in-position signal line of the connection harness;

[0024] After the control module of the energy storage inverter detects the standby signal, it enters the standby state;

[0025] The control module of the energy storage inverter communicates with another energy storage inverter through a communication bus, detects the level signals of amplitude, phase, and frequency required for parallel connection between the two, judges the synchronization information, and synchronously performs AC output through the AC output line based on the synchronization information.

[0026] In the technical solution of the embodiment of the present invention, by setting a parallel connection interface and a standby module, the standby module can output a standby signal to the in-position signal line of the energy storage inverter when the energy storage inverter is connected to the parallel connection port, so that the energy storage inverter enters the standby state. Therefore, when the energy storage inverter is connected to the parallel connection accessory, even if the energy storage inverter already has AC output when connected to the parallel connection accessory, the standby module will make the energy storage inverter enter the standby state first, and no AC output is performed in the standby state. When the energy storage inverters that need to be paralleled are all connected to the parallel connection interfaces, the communication buses of the energy storage inverters will be electrically connected under the action of the parallel connection accessory, so that the energy storage inverters can communicate for data exchange, detect the level signals of amplitude, phase, and frequency required for parallel connection, judge the synchronization information, and synchronously perform AC output through their own AC output lines based on the synchronization information, realizing synchronous output after multiple energy storage inverters are paralleled, and solving the problem that faults or error reports will occur after the energy storage inverters are paralleled when there is already AC output.

[0027] It should be understood that the content described in this part is not intended to identify the key or important features of the embodiments of the present invention, nor is it used to limit the scope of the present invention. Other features of the present invention will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 FIG. is a schematic structural diagram of the connection between a parallel connection accessory and an energy storage inverter provided in Embodiment 1 of the present invention;

[0030] Figure 2 This is a schematic structural diagram of another parallel connection accessory connected to an energy storage inverter provided in the first embodiment of the present invention.

[0031] Wherein: 11, in-position signal line; 12, communication bus; 13, AC output line; 14, signal ground wire; 15, control module; 2, parallel connection accessory; 21, parallel connection main body; 211, first side; 212, second side; 213, third side; 22, standby module; 23, power output interface; 24, parallel connection interface; 241, in-position signal connection terminal; 242, communication signal connection terminal; 243, AC output connection terminal; 244, signal ground connection terminal; 3, electrical appliance. Detailed implementation manners

[0032] In order to enable those skilled in the art to better understand the solution of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0033] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and do not necessarily need to be used to describe a specific order or sequence. It should be understood that such data can be interchanged under appropriate circumstances so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device including a series of steps or units does not necessarily have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0034] Embodiment 1

[0035] Figure 1 This is a schematic structural diagram of a parallel connection accessory 2 connected to an energy storage inverter provided in the first embodiment of the present invention. This embodiment is applicable to the case of parallel connection of multiple energy storage inverters, and the energy storage inverter can specifically be a portable energy storage inverter. As Figure 1 shown, the energy storage inverter includes a connection wire harness, and the connection wire harness includes an in-position signal line 11, a communication bus 12, and an AC output line 13. Among them, the in-position signal line 11 refers to a signal line representing the in-position signal of the energy storage inverter, the communication bus 12 refers to a bus for various output transceivers of the energy storage inverter, and the AC output line 13 refers to a signal line for the AC output of the energy storage inverter.

[0036] The parallel connection accessory 2 includes a parallel connection main body 21, on which a standby module 22, a power output interface 23 and a parallel connection interface 24 are provided; the number of the parallel connection interfaces 24 is multiple, and the multiple parallel connection interfaces 24 are used for corresponding connection with the connection wire bundles of multiple energy storage inverters one by one. The parallel connection interface 24 includes an in-position signal connection terminal 241, a communication signal connection terminal 242 and an AC output connection terminal 243, and the in-position signal connection terminal 241, the communication signal connection terminal 242 and the AC output connection terminal 243 are used for corresponding connection with an in-position signal wire 11, a communication bus 12 and an AC output wire 13 one by one.

[0037] Among them, the parallel connection interface 24 refers to a port that can be connected and matched with the connection wire bundle. When the connection wire bundle is connected to the parallel connection interface 24, the in-position signal wire 11, the communication bus 12 and the AC output wire 13 on the connection wire bundle will be automatically electrically connected to the in-position signal connection terminal 241, the communication signal connection terminal 242 and the AC output connection terminal 243 on the parallel connection interface 24, so as to realize the connection between the energy storage inverter and the parallel connection accessory 2.

[0038] The standby module 22 is electrically connected to the in-position signal connection terminal 241 and is used for outputting a standby signal to the in-position signal wire 11 of the energy storage inverter when the energy storage inverter is connected to the parallel connection port, so that the energy storage inverter enters the standby state. Among them, the standby state refers to a state without AC output, and the standby module 22 refers to a module that can output a standby signal to the in-position signal wire 11. When the in-position signal wire 11 of the energy storage inverter receives the standby signal, it will enter the standby state.

[0039] The communication signal connection terminals 242 of the multiple parallel connection interfaces 24 are all electrically connected and are used for enabling multiple energy storage inverters to communicate when the energy storage inverters are connected to the parallel connection port, detecting the level signals of the amplitude, phase and frequency required for parallel connection, so as to judge the synchronization information, and synchronously performing AC output through the AC output wire 13 based on the synchronization information. Among them, since the communication signal connection terminals 242 of the multiple parallel connection interfaces 24 are all electrically connected, and the communication signal connection terminal 242 is used for connecting the communication bus 12 of the energy storage inverter, when the connection wire bundles of the multiple energy storage inverters are connected to the parallel connection port, the communication buses 12 of the multiple energy storage inverters will be electrically connected, so that the multiple energy storage inverters can communicate. When the multiple energy storage inverters communicate with each other, the output voltage, phase and frequency between the multiple energy storage inverters can be adjusted, and the two can be in a synchronous state through communication, so as to meet the condition of simultaneous output.

[0040] The AC output connection terminals 243 of multiple parallel connection interfaces 24 are electrically connected to the power output interface 23, and the power output interface 23 is used to connect to the electrical appliance 3. Among them, when in use, the electrical appliance 3 can be electrically connected to the power output interface 23 through an electric wire. Since the AC output connection terminal 243 of the parallel connection interface 24 is electrically connected to the AC output line 13 of the energy storage inverter, when the energy storage inverter performs AC output through the AC output line 13, the AC output can pass through the AC output connection terminal 243 and finally be transmitted to the electrical appliance 3 by the power output interface 23. Since the AC output connection terminals 243 of multiple parallel connection interfaces 24 are electrically connected to the power output interface 23, when multiple energy storage inverters are all connected to the parallel connection interface 24, the AC outputs of multiple energy storage inverters are finally all transmitted to the electrical appliance 3 by the power output interface 23, achieving the effect of parallel connection.

[0041] In the above solution, by setting the parallel connection interface 24 and the standby module 22, the standby module 22 can output a standby signal to the in-position signal line 11 of the energy storage inverter when the energy storage inverter is connected to the parallel connection port, so that the energy storage inverter enters the standby state. Therefore, when the energy storage inverter is connected to the parallel connection accessory 2, even if the energy storage inverter already has an AC output when connected to the parallel connection accessory 2, the standby module 22 will also cause the energy storage inverter to enter the standby state first, and no AC output is performed in the standby state. When the energy storage inverters that need to be paralleled are all connected to the parallel connection interface 24, the communication buses 12 of the energy storage inverters will be electrically connected under the action of the parallel connection accessory 2, so that the energy storage inverters can communicate for data exchange, detect the level signals of amplitude, phase, and frequency required for parallel connection to judge the synchronization information, and synchronously perform AC output through their own AC output lines 13 based on the synchronization information, realizing synchronous output after multiple energy storage inverters are paralleled, and solving the problem that the energy storage inverter will malfunction or report an error after paralleling when there is already an AC output.

[0042] In an alternative embodiment of the present invention, the standby signal is a low-level signal. Among them, when the energy storage inverter detects that the in-position signal is a high level, it is in the working state, and when the energy storage inverter is at a low level, it will enter the standby state. By making the standby signal a low-level signal, no matter whether there is an AC output when the energy storage inverter is connected to the parallel connection accessory 2, the standby module 22 will output a low-level signal to the in-position signal line 11 of the energy storage inverter, making the in-position signal a low level, so that the energy storage inverter will enter the standby state and stop AC output, solving the problem that the energy storage inverter will malfunction or report an error after paralleling when there is already an AC output.

[0043] Based on the above embodiments, the energy storage inverter includes a signal ground wire 14, and the parallel connection interface 24 further includes a signal ground connection terminal 244, and the signal ground connection terminal 244 is used to connect the signal ground wire 14 of the energy storage inverter; one end of the standby module 22 is connected to the signal ground connection terminal 244, and the other end is connected to the in-position signal connection terminal 241, and the standby module 22 is used to electrically connect the signal ground connection terminal 244 and the in-position signal connection terminal 241.

[0044] Among them, the signal ground wire 14 of the energy storage inverter represents the signal ground. When the in-position signal wire 11 is connected to the signal ground wire 14, the in-position signal will become low level under the action of the signal ground, causing the energy storage inverter to enter the standby state. Since one end of the standby module 22 is connected to the signal ground connection terminal 244 and the other end is connected to the in-position signal connection terminal 241, and the standby module 22 is used to electrically connect the signal ground connection terminal 244 and the in-position signal connection terminal 241, so when the signal ground connection terminal 244 and the in-position signal connection terminal 241 are electrically connected, since when the energy storage inverter is connected to the parallel connection accessory 2, the signal ground connection terminal 244 is connected to the signal ground wire 14 and the in-position signal connection terminal 241 is connected to the in-position signal wire 11, so at this time the signal ground wire 14 will be connected to the signal ground wire 14, realizing outputting a low level signal to the signal ground wire 14 to make the energy storage inverter enter the standby state.

[0045] Exemplarily, the standby module 22 includes at least one of a metal wire, a mechanical switch, a relay switch, a semiconductor switch, and a digital signal control switch. Among them, the metal wire, the mechanical switch, the relay switch, the semiconductor switch, and the digital signal control switch can all conduct the circuit. Since one end of the standby module 22 is connected to the signal ground connection terminal 244 and the other end is connected to the in-position signal connection terminal 241, so by making the standby module 22 include at least one of a metal wire, a mechanical switch, a relay switch, a semiconductor switch, and a digital signal control switch, the effect of electrically connecting the signal ground connection terminal 244 and the in-position signal connection terminal 241 can be realized.

[0046] In an alternative embodiment of the present invention, the parallel connection main body 21 includes a parallel connection box, the number of the parallel connection interfaces 24 is two, and the two parallel connection interfaces 24 are respectively arranged on the opposite first side 211 and second side 212 of the parallel connection box, and the power output interface 23 is arranged on the third side 213 of the parallel connection box, and the third side 213 is perpendicular to the first side 211.

[0047] Among them, since the two parallel connection interfaces 24 are respectively arranged on the opposite first side 211 and second side 212 of the parallel connection box, and the power output interface 23 is arranged on the third side 213 of the parallel connection box perpendicular to the first side 211, so when the parallel connection box is connected to the energy storage inverter and the electrical appliance 3, the energy storage inverter and the electrical appliance 3 are located in different orientations, and it is not easy to interfere with each other, and the connection is relatively convenient.

[0048] As shown Figure 2 below, a specific embodiment is used to illustrate the specific process of multiple energy storage inverters paralleling through the paralleling accessory 2. In this embodiment, the number of energy storage inverters is two, namely A and B. The AC output of energy storage inverter A is L1 / N1, the signal ground is GND1, the communication bus 12 is CANL1 / CANH1, and the on-site signal is S1. The AC output of energy storage inverter B is L2 / N2, the signal ground is GND2, the communication bus 12 is CANL2 / CANH2, and the on-site signal is S2. CANL1 / CANH1 is used for various data transceiver of energy storage inverter A, and CANL2 / CANH2 is used for various data transceiver of energy storage inverter B. At the same time, in this embodiment, the standby module 22 is a metal wire.

[0049] When energy storage inverter A is connected to the paralleling accessory 2, since the metal wire electrically connects the signal ground connection terminal 244 and the on-site signal connection terminal 241 of the paralleling accessory 2, the S1 of the portable energy storage inverter A is shorted to GND1 to be at a low level. After the energy storage inverter A internally recognizes that S1 is a low-level signal, the portable energy storage inverter A immediately stops the AC output and enters the standby state.

[0050] When energy storage inverter B is not connected to the paralleling accessory 2, its output state is not controlled by the paralleling accessory 2. When the portable energy storage inverter B is connected to the paralleling accessory 2, the S2 of the energy storage inverter B is shorted to GND2 to be at a low level. After the energy storage inverter B recognizes that S2 is a low-level signal, the portable energy storage inverter B immediately stops the AC output and enters the standby state. At this time, the paralleling accessory 2 connects the CANL1 / CANH1 of the energy storage inverter A to the CANL2 / CANH2 of the energy storage inverter B, and the status data of the energy storage inverter A and the energy storage inverter B communicate through CANL1 / CANH1 and CANL2 / CANH2 respectively, achieving equal voltage, the same phase, equal frequency, and synchronously performing AC output.

[0051] Assume that in this case, the parameters of energy storage inverter A are: 2.2 KWh, the inverter output parameters are 230VAC / 50Hz / 10A, and the parameters of energy storage inverter B are: 2.2 KWh, the inverter output parameters are 230VAC / 50Hz / 10A. After passing through the paralleling accessory 2, 4.4 KWh can be obtained, and the inverter output is 230VAC / 50Hz / 20A.

[0052] Assume that in this case, the parameters of energy storage inverter A are: 1 KWh, the inverter output parameters are 230VAC / 50Hz / 5A, and the parameters of energy storage inverter B are: 2.2 KWh, the inverter output parameters are 230VAC / 50Hz / 10A. After passing through the paralleling accessory 2, 3.2 KWh can be obtained, and the inverter output is 230VAC / 50Hz / 15A.

[0053] From the above principle analysis, the following conclusion can be drawn: After the energy storage inverter products are paralleled through the parallel connection accessory 2, the output power can be increased to meet the user's needs.

[0054] In addition, whether the energy storage inverter A or the energy storage inverter B is connected to the parallel connection accessory 2 first, regardless of whether there is an AC output when the energy storage inverter A and the energy storage inverter B are connected, when the energy storage inverter is connected to the parallel connection accessory 2, the parallel connection accessory 2 will make the energy storage inverter enter the standby state first. When both the energy storage inverter A and the energy storage inverter B are connected to the parallel connection accessory 2, their status data communicate through CANL1 / CANH1 and CANL2 / CANH2 respectively, achieving equal voltage, the same phase, equal frequency, and synchronously performing AC output, solving the problem that faults or error reports may occur after paralleling when the energy storage inverter already has an AC output.

[0055] Embodiment 2

[0056] Embodiment 2 of the present invention provides an energy storage inverter, as Figure 1 shown. The energy storage inverter includes a control module 15 and a connection wire harness. The connection wire harness includes an in-position signal line 11, a communication bus 12, and an AC output line 13. The control module 15 is electrically connected to both the communication bus 12 and the in-position signal line 11. The control module 15 is used to obtain a standby signal through the in-position signal line 11 and be in the standby state when the standby signal is obtained, and communicate with another energy storage inverter through the communication bus 12 to detect the level signals of the amplitude, phase, and frequency required for paralleling the two, so as to judge the synchronization information, and synchronously perform AC output through the AC output line 13 based on the synchronization information.

[0057] Among them, the in-position signal line 11 refers to the line representing the in-position signal of the energy storage inverter, the communication bus 12 refers to the bus used for various output transmissions and receptions of the energy storage inverter, and the AC output line 13 refers to the line for the energy storage inverter to perform AC output. When the control module 15 obtains the standby signal, it is in the standby state, and at this time, the AC output of the AC output line 13 is cut off. When the energy storage inverter is connected to the parallel connection accessory 2, even if the energy storage inverter already has an AC output when connecting to the parallel connection accessory 2, the energy storage inverter will first obtain the standby signal and enter the standby state, and no AC output is performed in the standby state. When the energy storage inverters to be paralleled are all connected to the parallel connection interface 24, the communication buses 12 of the energy storage inverters will be electrically connected under the action of the parallel connection accessory 2, so that the energy storage inverters can communicate for data exchange, detect the level signals of the amplitude, phase, and frequency required for paralleling, so as to judge the synchronization information, and synchronously perform AC output through their own AC output lines 13 based on the synchronization information, realizing synchronous output after paralleling of multiple energy storage inverters, and solving the problem that faults or error reports may occur after paralleling when the energy storage inverter already has an AC output.

[0058] In an alternative embodiment of the present invention, the communication bus 12 is a CAN bus. Herein, CAN is the abbreviation of Controller Area Network, and it is one of the most widely used field buses in the world. It has many characteristics such as high communication rate, easy implementation, and high cost performance. Therefore, using the CAN bus facilitates the communication interaction between energy storage inverters.

[0059] In an alternative embodiment of the present invention, the control module 15 is an MCU. The microcontroller unit (MCU), also known as a single-chip microcomputer or a microcontroller, is a computer-on-a-chip that appropriately reduces the frequency and specifications of the central processing unit (CPU) and integrates peripherals such as memory, timer, USB, A / D converter, UART, PLC, DMA, and even the LCD driver circuit on a single chip to perform different combined controls for different application scenarios.

[0060] In an alternative embodiment of the present invention, the standby signal is a low-level signal. When the energy storage inverter detects that the in-position signal is high, it is in the working state. When the energy storage inverter is low, it will enter the standby state. By making the standby signal a low-level signal, regardless of whether there is an AC output when the energy storage inverter is connected to the parallel connection accessory 2, when the in-position signal line 11 of the energy storage inverter obtains the standby signal, the in-position signal will be low, and thus the energy storage inverter will enter the standby state and stop the AC output, solving the problem that the energy storage inverter may malfunction or report an error after parallel connection when there is already an AC output.

[0061] Embodiment III

[0062] Embodiment III of the present invention provides a method for parallel connection of energy storage inverters. The method for parallel connection of energy storage inverters includes:

[0063] S1. Connect the connection harnesses of multiple energy storage inverters to the multiple parallel connection interfaces of the parallel connection accessory one by one. Herein, the one-by-one connection means that the connection harness of one energy storage inverter is connected to one parallel connection port, and the connection harness can be cooperated with some electronic connectors to achieve the connection and cooperation with the parallel connection interface.

[0064] S2. The parallel connection accessory outputs a standby signal to the in-position signal line of the connection harness. The standby signal is a signal indicating that the energy storage inverter enters the standby state.

[0065] S3. After the control module of the energy storage inverter detects the standby signal, it enters the standby state. Among them, in the standby state, the control module turns off the AC output.

[0066] S4. The control module of the energy storage inverter communicates with another energy storage inverter through the communication bus, detects the level signals of amplitude, phase, and frequency required for parallel operation of the two, judges the synchronization information, and synchronously performs AC output through the AC output line based on the synchronization information.

[0067] Among them, when the energy storage inverters that need to be paralleled are all connected to the parallel operation interface, the communication buses of the energy storage inverters will be electrically connected under the action of the parallel operation accessories, so that the energy storage inverters can communicate for data exchange, detect the level signals of amplitude, phase, and frequency required for parallel operation, judge the synchronization information, and synchronously perform AC output through their own AC output lines based on the synchronization information, realizing synchronous output after multiple energy storage inverters are paralleled, and solving the problem that the energy storage inverter will malfunction or report an error after paralleling when there is an existing AC output.

[0068] It should be understood that the various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps described in the present invention can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solution of the present invention can be achieved, and no limitation is imposed herein.

[0069] The above specific embodiments do not constitute a limitation to the protection scope of the present invention. Those skilled in the art should understand that various modifications, combinations, sub - combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims

1. A parallel connection accessory for parallel connection of multiple energy storage inverters. The energy storage inverters are connected to the parallel connection accessory through connection wire harnesses. The connection wire harnesses include in-position signal lines (11), communication buses (12), and AC output lines (13); Characterized in that, the parallel connection accessory includes a parallel connection main body (21), and a standby module (22), a power output interface (23), and a parallel connection interface (24) are provided on the parallel connection main body (21); the number of the parallel connection interfaces (24) is multiple, and the parallel connection interfaces (24) are used to be correspondingly connected to the multiple connection wire harnesses one by one; the parallel connection interface (24) includes an in-position signal connection terminal (241), a communication signal connection terminal (242), and an AC output connection terminal (243). The in-position signal connection terminal (241), the communication signal connection terminal (242), and the AC output connection terminal (243) are used to be correspondingly connected to the in-position signal line (11), the communication bus (12), and the AC output line (13) one by one; the standby module (22) is electrically connected to the in-position signal connection terminal (241), and is used to output a standby signal to the in-position signal line (11) of the energy storage inverter when the energy storage inverter is connected to the parallel connection interface, so that the energy storage inverter enters a standby state; the communication signal connection terminals (242) of the multiple parallel connection interfaces (24) are all electrically connected, and are used to enable communication between the multiple energy storage inverters when the energy storage inverters are connected to the parallel connection ports, detect the level signals of amplitude, phase, and frequency required for parallel connection to judge synchronization information, and perform AC output synchronously through the AC output line (13) based on the synchronization information; the AC output connection terminals (243) of the multiple parallel connection interfaces (24) are electrically connected to the power output interface (23), and the power output interface (23) is used to connect to an electrical appliance (3).

2. The parallel connection accessory according to claim 1, Characterized in that, the standby signal is a low-level signal.

3. The parallel connection accessory according to claim 2, Characterized in that, the energy storage inverter includes a signal ground wire (14), and the parallel connection interface (24) further includes a signal ground connection terminal (244). The signal ground connection terminal (244) is used to connect the signal ground wire (14) of the energy storage inverter; one end of the standby module (22) is connected to the signal ground connection terminal (244), and the other end is connected to the in-position signal connection terminal (241). The standby module (22) is used to electrically connect the signal ground connection terminal (244) and the in-position signal connection terminal (241).

4. The parallel connection accessory according to claim 3, Characterized in that, the standby module (22) includes at least one of a metal wire, a mechanical switch, a relay switch, a semiconductor switch, and a digital signal control switch.

5. The parallel connection accessory according to any one of claims 1 to 4, Characterized in that, The parallel connection main body (21) includes a parallel connection box. The number of the parallel connection interfaces (24) is two, and the two parallel connection interfaces (24) are respectively arranged on the opposite first side (211) and second side (212) of the parallel connection box. The power output interface (23) is arranged on the third side (213) of the parallel connection box, and the third side (213) is perpendicular to the first side (211).

6. A energy storage inverter, characterized in that, the energy storage inverter includes a control module (15) and a connection wire harness. The connection wire harness includes an in-position signal wire (11), a communication bus (12) and an AC output wire (13); the control module (15) is electrically connected to both the communication bus (12) and the in-position signal wire (11). The control module (15) is used to obtain a standby signal through the in-position signal wire (11), and be in a standby state when the standby signal is obtained, and communicate with another energy storage inverter through the communication bus (12), detect the level signals of the amplitude, phase and frequency required for parallel connection of the two, so as to judge the synchronization information, and synchronously perform AC output through the AC output wire (13) based on the synchronization information.

7. The energy storage inverter according to claim 6, characterized in that, the communication bus (12) is a CAN bus.

8. The energy storage inverter according to claim 6 or 7, characterized in that, the control module (15) is an MCU.

9. The energy storage inverter according to claim 6 or 7, characterized in that, the standby signal is a low-level signal.

10. A parallel connection method for an energy storage inverter, characterized in that, it includes: making the connection wire harnesses of multiple energy storage inverters be correspondingly connected to multiple parallel connection interfaces of a parallel connection accessory one by one; the parallel connection accessory outputs a standby signal to the in-position signal wire of the connection wire harness; the control module of the energy storage inverter enters a standby state after detecting the standby signal; the control module of the energy storage inverter communicates with another energy storage inverter through a communication bus, detects the level signals of the amplitude, phase and frequency required for parallel connection of the two, so as to judge the synchronization information, and synchronously perform AC output through an AC output wire based on the synchronization information.

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