CN115065132B

CN115065132B - Energy storage system and method for identifying connection interface of inverter and battery pack

Info

Publication number: CN115065132B
Application number: CN202210990611.XA
Authority: CN
Inventors: 雷健华; 秦赓; 黎香壮; 张华�; 游永亮
Original assignee: Shenzhen Poweroak Newener Co Ltd
Current assignee: Shenzhen Delian Minghai New Energy Co ltd
Priority date: 2022-08-18
Filing date: 2022-08-18
Publication date: 2022-11-08
Anticipated expiration: 2042-08-18
Also published as: CN115065132A

Abstract

The invention discloses an energy storage system and a method for identifying a connection interface between an inverter and a battery pack, wherein the energy storage system comprises the inverter and a plurality of battery packs connected with the inverter, the inverter is provided with an inversion control unit and at least two inversion interface units, and each battery pack is respectively provided with a battery control unit and two battery interface units connected with each other; the inversion control unit is provided with inversion I/O interfaces with the same number as the inversion interface units, and the battery control unit is provided with battery I/O interfaces; each inversion I/O interface respectively generates an identification signal and sends the identification signal to each battery identification signal interface, and the identification signals output by each inversion I/O interface are different; each battery control unit determines interface connection information of the battery pack and the inverter according to the received identification signal and sends the interface connection information to the inverter; and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information. The invention can realize the automatic identification of the inverter and the wiring mode of the battery pack.

Description

Energy storage system and method for identifying connection interface of inverter and battery pack

Technical Field

The invention relates to the technical field of energy storage, in particular to an energy storage system and a method for identifying a connection interface between an inverter and a battery pack.

Background

With the further overcoming of the technical difficulties of lithium batteries and the like, energy storage products are developed at a high speed, the updating of the products is more and more advanced, and meanwhile, users also put forward various requirements on the energy storage products; in the market, there are mobile energy storage series products which are convenient for moving and have 1 inverter dragging several battery packs, that is, the scheme that 1 inverter drags several battery packs is adopted, two interfaces are designed and reserved for charging and discharging interfaces of the inverter, and two charging and discharging interfaces of the battery packs are also adopted, so that in the use stage, the inverter and the battery packs are connected in various ways, for example, 4 battery packs are matched for 1 inverter, and the connection way has various combination connection methods, wherein, two common connection methods are shown in fig. 1 and fig. 2. The first wiring mode: four battery packs 20 (specifically, a first battery pack 201, a second battery pack 202, a third battery pack 203, and a fourth battery pack 204) are equally divided at charging and discharging ports of the inverter 10, that is, the first battery pack 201 and the second battery pack 202 are connected to one interface of the inverter 10, the third battery pack 203 and the fourth battery pack 204 are connected to the other interface of the inverter 10, and the second connection mode: the four battery packs (including the first battery pack 201, the second battery pack 202, the third battery pack 203 and the fourth battery pack 204) are pulled by hand, that is, the first battery pack 201, the second battery pack 202, the third battery pack 203 and the fourth battery pack 204 are all connected to the same interface of the inverter. In the first connection mode, the number of the battery packs attached to the two interfaces of the inverter 10 is balanced, so that the inverter 10 can work reliably and fully; in the second connection mode, only one interface of the inverter 10 is provided with 4 battery packs to work, so that the inverter 10 cannot output full power or the connection line is easy to overload, and potential safety hazards exist. The inverter in the prior art cannot recognize which way the battery pack is connected thereto.

In order to allow the inverter to operate reliably and at full power and to fully function with the battery pack, most designers currently adopt the following method to avoid the problem that the inverter cannot identify the mode in which the battery pack is connected to the battery pack: 1. by adopting a manual instruction mode, users are informed of wiring according to a first wiring mode; 2. thickening a cable for connecting the inverter and the battery pack, wherein the key point is a current-carrying power cable so as to achieve the purpose of safe use under the full-power working condition; in the method 1, because the related users are wide, all users cannot be guaranteed to notice the problem, and potential safety hazards exist in use; in the method 2, although the potential safety hazard can be avoided, the cost of connecting the cable is high, and meanwhile, the battery pack at the tail end needs to be connected with the inverter through four connecting wires, particularly the design scheme of the low-voltage battery pack, so that the loss of the cable is not negligible. Thus, the connection result of the first connection mode is desired, and the inverter needs to be able to recognize in which mode the battery pack is connected; the advantages of the first wiring mode include: 1. the sum of the current carrying capacities of the cables respectively connected to the interface 1 and the interface 2 of the inverter is larger than the current carrying required when the inverter is fully loaded; 2. the distance from the last battery pack to the inverter is shortened, and the loss of a current-carrying wire is low. In actual use, because the products relate to a wide range of users, it is often difficult to operate all the products according to the first wiring mode.

The above background disclosure is only for the purpose of assisting understanding of the concept and technical solution of the present invention and does not necessarily belong to the prior art of the present patent application, and should not be used for evaluating the novelty and inventive step of the present application in the case that there is no clear evidence that the above content is disclosed at the filing date of the present patent application.

Disclosure of Invention

In order to solve the technical problems, the invention provides an energy storage system and a method for identifying a connection interface between an inverter and a battery pack, which can solve the problem that the existing inverter cannot identify the mode of connecting the battery pack with the inverter.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the invention discloses an energy storage system, which comprises an inverter and a plurality of battery packs connected with the inverter, wherein the inverter is provided with an inversion control unit and at least two inversion interface units, and each battery pack is respectively provided with a battery control unit and two battery interface units connected with each other; the inverter control unit is provided with inverter I/O interfaces with the same number as the inverter interface units, and the battery control unit is provided with battery I/O interfaces; each inversion interface unit comprises an inversion identification signal interface, each battery interface unit comprises a battery identification signal interface, and when the battery interface unit of the battery pack is connected to one inversion interface unit of the inverter, the battery identification signal interface is correspondingly connected with one inversion identification signal interface; each inversion I/O interface is correspondingly connected with each inversion identification signal interface respectively, and the battery I/O interface is connected with the battery identification signal interface; the inverter control unit generates identification signals through the inverter I/O interfaces respectively, and sends the identification signals to the battery identification signal interfaces of the battery packs through the inverter identification signal interfaces, wherein the identification signals output by the inverter I/O interfaces are different; the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal, and sends the interface connection information to the inverter; and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack.

In some embodiments, the inverter identification signal interface comprises an inverter identification signal pin, the battery identification signal interface comprises a battery identification signal pin, the battery identification signal pin is correspondingly connected with the inverter identification signal pin when the battery pack is connected with the inverter, and the inverter identification signal pin is correspondingly connected with the inverter I/O interface; wherein, the difference of the identification signals output by the inverting I/O interfaces at least comprises the difference of the identification signal frequency respectively generated by the inverting I/O interfaces.

In other embodiments, the number of the inverter interface units in the inverter is n, the inverter identification signal interface and the battery identification signal interface respectively include n inverter identification signal pins and n battery identification signal pins, the n inverter identification signal pins are respectively a first to nth inverter identification signal pins, the n battery identification signal pins are respectively a first to nth battery identification signal pins, and the first to nth inverter identification signal pins are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner; each inversion I/O interface is correspondingly connected with one inversion identification signal pin in each inversion identification signal interface, and the serial numbers of the inversion identification signal pins connected with each inversion I/O interface are different; in the first to nth inversion identification signal pins in each inversion identification signal interface, except the inversion identification signal pin with the corresponding serial number connected with the inversion I/O interface, the inversion identification signal pins with other serial numbers are all grounded, wherein n is an integer greater than or equal to 2, and the difference of the identification signals output by each inversion I/O interface at least comprises the different serial numbers of the inversion identification signal pins connected with each inversion I/O interface.

Furthermore, the number of the n battery I/O interfaces is set in the battery control unit, the n battery I/O interfaces are respectively the first to nth battery I/O interfaces, and the first to nth battery I/O interfaces are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner.

Further, the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

Furthermore, each battery pack is also provided with isolation units with the same number as the battery I/O interfaces, and each battery I/O interface is connected with the battery identification signal interface through the isolation unit.

In a second aspect, the invention discloses a method for identifying a connection interface between an inverter and a battery pack, which is applied to the energy storage system and comprises the following steps:

s1: the inverter establishes communication connection with all the connected battery packs;

s2: the inversion control unit respectively generates identification signals through each inversion I/O interface and sends the identification signals to the battery identification signal interfaces of the battery packs through the inversion identification signal interfaces, wherein the identification signals output by the inversion I/O interfaces are different;

s3: the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal, and sends the interface connection information to the inverter;

s4: and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack.

In some embodiments, the inverter identification signal interface comprises an inverter identification signal pin, the battery identification signal interface comprises a battery identification signal pin, the battery identification signal pin is correspondingly connected with the inverter identification signal pin when the battery pack is connected with the inverter, and the inverter identification signal pin is correspondingly connected with the inverter I/O interface; in the step S2, the positions where the identification signals output by the inverting I/O interfaces are different at least include different frequencies of the identification signals respectively generated by the inverting I/O interfaces; and in step S3, the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the frequency of the received identification signal.

In other embodiments, the number of the inverter interface units in the inverter is n, the inverter identification signal interface and the battery identification signal interface respectively include n inverter identification signal pins and n battery identification signal pins, the n inverter identification signal pins are respectively first to nth inverter identification signal pins, the n battery identification signal pins are respectively first to nth battery identification signal pins, and the first to nth inverter identification signal pins are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner; each inversion I/O interface is correspondingly connected with one inversion identification signal pin in each inversion identification signal interface, and the serial numbers of the inversion identification signal pins connected with each inversion I/O interface are different; in the first to nth inversion identification signal pins in each inversion identification signal interface, except the inversion identification signal pin with the corresponding serial number connected with the inversion I/O interface, the inversion identification signal pins with other serial numbers are all grounded; the battery control unit is provided with n battery I/O interfaces, the n battery I/O interfaces are respectively a first battery I/O interface to an nth battery I/O interface, the first battery I/O interface to the nth battery I/O interface are respectively connected with a first battery identification signal pin to an nth battery identification signal pin in a one-to-one correspondence mode, wherein n is an integer greater than or equal to 2; in the step S2, the difference between the identification signals output by the inverting I/O interfaces at least includes the difference between the serial numbers of the inverting identification signal pins connected to the inverting I/O interfaces; and in step S3, the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

Further, the method for identifying the connection interface between the inverter and the battery pack further comprises the following steps: calculating the number of the battery packs respectively connected to each inversion interface unit in the inverter, calculating the difference value of the number of the battery packs connected to each two inversion interface units, and if all the difference values are less than or equal to 1, judging that the inverter provides output for a normal mode; and if the difference value is larger than 1, judging that the inverter provides output for the abnormal mode.

Compared with the prior art, the invention has the advantages that: the energy storage system and the method for identifying the connection interface between the inverter and the battery pack are applied to the energy storage system with the split design of the inverter and the battery pack, wherein the energy storage system with the split design can realize flexible expansion of the energy storage system by increasing or decreasing the number of the battery packs; based on the energy storage system, the inversion control unit respectively generates identification signals through each inversion I/O interface and sends the identification signals to the battery identification signal interfaces of each battery pack, wherein the identification signals output by each inversion I/O interface are different; the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal and sends the interface connection information to the inverter; the inverter can finally determine the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack, so that the inverter can automatically identify the connection interface with the battery pack.

Further, the method for identifying the connection interface between the inverter and the battery pack calculates the number of the battery packs respectively connected to each inversion interface unit in the inverter, calculates the difference value of the number of the battery packs connected to each two inversion interface units, and judges that the inverter provides output for a normal mode if all the difference values are less than or equal to 1; if the difference value is larger than 1, judging that the inverter provides output for the abnormal mode; therefore, whether the connection mode between the interfaces meets the requirement or not is judged.

Drawings

FIG. 1 is a schematic diagram of a first wiring method of an inverter with four battery packs in the prior art;

FIG. 2 is a schematic diagram of a second connection mode of an inverter with four battery packs in the prior art;

fig. 3 is a schematic diagram of an inverter of an energy storage system with four battery packs according to an embodiment of the invention;

FIG. 4 is an enlarged schematic view of the wiring structure at the inverter of FIG. 3;

fig. 5a is an enlarged schematic view of a wiring structure of the first battery pack in fig. 3;

fig. 5b is an enlarged schematic view of a wiring structure of the third battery pack in fig. 3;

fig. 6 is a flowchart of an inverter and battery pack connection interface identification method of an energy storage system according to a second embodiment of the present invention;

fig. 7 is a schematic diagram of an inverter of an energy storage system with four battery packs according to a third embodiment of the present invention;

FIG. 8 is an enlarged schematic view of the wiring structure at the inverter of FIG. 7;

fig. 9a is an enlarged schematic view of a wiring structure of the first battery pack in fig. 7;

fig. 9b is an enlarged schematic view of a wiring structure of the third battery pack in fig. 7;

fig. 10 is a flowchart of an inverter and battery pack connection interface identification method of an energy storage system according to a fourth embodiment of the present invention.

Detailed Description

The embodiments of the present invention will be described in detail below. It should be emphasized that the following description is merely exemplary in nature and is in no way intended to limit the scope of the invention or its applications.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element. In addition, the connection may be for either a fixed or circuit/signal communication role.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or to implicitly indicate the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the embodiments of the present invention, "a plurality" means two or more unless specifically limited otherwise.

In order to make the inverter work reliably and make the battery pack function sufficiently, the connection result of the first connection mode shown in fig. 1 is expected, and the inverter needs to be able to identify the mode in which the battery pack is connected; the first wiring mode has the advantages that: (1) The sum of the current carrying capacities of the cables respectively connected to the interface 1 and the interface 2 of the inverter is larger than the current carrying required when the inverter is fully loaded; (2) The distance from the last 1 battery pack to the inverter is shortened, and the loss of a current-carrying line is low. In actual use, because the products relate to a wide range of users, the first wiring mode is difficult to operate in all cases, and therefore, the automatic identification wiring mode of the inverter and the battery PACK is needed.

In order to enable the connection mode of the inverter and the battery pack to be adjusted according to actual conditions under any conditions, the embodiment of the invention provides a specific wiring structure of the inverter and the battery pack of the energy storage system and a corresponding identification method.

The invention discloses an energy storage system, which comprises an inverter and a plurality of battery packs connected with the inverter, wherein the inverter is provided with an inversion control unit and at least two inversion interface units, and each battery pack is respectively provided with a battery control unit and two battery interface units connected with each other; the inversion control unit is provided with inversion I/O interfaces with the same number as the inversion interface units, and the battery control unit is provided with battery I/O interfaces; each inversion interface unit comprises an inversion identification signal interface, each battery interface unit comprises a battery identification signal interface, and when the battery interface unit of the battery pack is connected with one inversion interface unit of the inverter, the battery identification signal interface is correspondingly connected with one inversion identification signal interface; each inversion I/O interface is correspondingly connected with each inversion identification signal interface, and the battery I/O interface is connected with the battery identification signal interface; the inverter control unit respectively generates identification signals through each inverter I/O interface and sends the identification signals to the battery identification signal interfaces of each battery pack through the inverter identification signal interfaces, wherein the identification signals output by the inverter I/O interfaces are different; the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal, and sends the interface connection information to the inverter; and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack.

Corresponding to the energy storage system of the embodiment, the invention discloses a method for identifying a connection interface between an inverter and a battery pack, which comprises the following steps:

s2: the inversion control unit respectively generates identification signals through each inversion I/O interface and sends the identification signals to the battery identification signal interfaces of each battery pack through the inversion identification signal interfaces, wherein the identification signals output by the inversion I/O interfaces are different;

In the energy storage system of some embodiments, the inverter identification signal interface includes an inverter identification signal pin, the battery identification signal interface includes a battery identification signal pin, and when the battery pack is connected to the inverter, the battery identification signal pin is correspondingly connected to the inverter identification signal pin, and the inverter identification signal pin is correspondingly connected to the inverter I/O interface; wherein, the different positions of the identification signals output by the inversion I/O interfaces at least comprise different frequencies of the identification signals respectively generated by the inversion I/O interfaces. Furthermore, each battery pack is also provided with isolation units with the same number as the battery I/O interfaces, and each battery I/O interface is connected with the battery identification signal interface through the isolation unit.

Corresponding to the energy storage system of the above embodiment, in the method for identifying the connection interface between the inverter and the battery pack disclosed by the invention, the difference of the identification signals output by the inverter I/O interfaces in the step S2 at least comprises the difference of the frequencies of the identification signals respectively generated by the inverter I/O interfaces; and the battery control unit of each battery pack in step S3 determines the interface connection information between the battery pack and the inverter according to the frequency of the received identification signal.

In the energy storage system of some embodiments, the number of the inversion interface units in the inverter is n, the inversion identification signal interface and the battery identification signal interface respectively include n inversion identification signal pins and n battery identification signal pins, the n inversion identification signal pins are respectively a first inversion identification signal pin to an nth inversion identification signal pin, the n battery identification signal pins are respectively a first battery identification signal pin to an nth battery identification signal pin, and the first inversion identification signal pin to the nth inversion identification signal pin are respectively connected with the first battery identification signal pin to the nth battery identification signal pin in a one-to-one correspondence manner; wherein, each inversion I/O interface is correspondingly connected with one inversion identification signal pin in each inversion identification signal interface, and the serial numbers of the inversion identification signal pins connected with each inversion I/O interface are different; in the first to nth inversion identification signal pins in each inversion identification signal interface, except the inversion identification signal pin with the corresponding serial number connected with the inversion I/O interface, the inversion identification signal pins with other serial numbers are all grounded, wherein n is an integer greater than or equal to 2, and the different positions of the identification signals output by each inversion I/O interface at least comprise different serial numbers of the inversion identification signal pins connected with each inversion I/O interface.

Furthermore, the number of n battery I/O interfaces is set in the battery control unit, the n battery I/O interfaces are respectively the first to nth battery I/O interfaces, and the first to nth battery I/O interfaces are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner.

Furthermore, the battery control unit of each battery pack determines the interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

Corresponding to the energy storage system of the embodiment, in the method for identifying the connection interface between the inverter and the battery pack, the identification signals output by the inverting I/O interfaces in the step S2 are different at least in the positions including the different serial numbers of the inverting identification signal pins connected with the inverting I/O interfaces; and in step S3, the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

Further, the method for identifying the connection interface between the inverter and the battery pack further comprises the following steps: calculating the number of battery packs respectively connected to each inversion interface unit in the inverter, calculating the difference value of the number of battery packs connected to every two inversion interface units, and judging that the inverter provides output for a normal mode if all the difference values are less than or equal to 1; and if the difference value is larger than 1, judging that the inverter provides output for the abnormal mode.

The energy storage system and the inverter and battery pack connection interface identification method disclosed by the invention are further described in a plurality of specific embodiments.

Example one

As shown in fig. 3, an interface structure and a wiring diagram of an energy storage system provided in this embodiment are provided, where the energy storage system includes an inverter 10 and four battery packs 20 (specifically, a first battery pack 201, a second battery pack 202, a third battery pack 203, and a fourth battery pack 204) connected to the inverter 10.

Referring to fig. 4, the inverter 10 is provided with an inverter control unit 11 and two inverter interface units (the two inverter interface units specifically include an a interface unit 12 and a B interface unit 13), in this embodiment, the inverter control unit 11 is specifically an inverter MCU (micro control unit), and the inverter control unit 11 is provided with two inverter I/O interfaces (the two inverter I/O interfaces specifically include an I/O1 interface 111 and an I/O2 interface 112). Specifically, the a interface unit 12 includes an a current-carrying interface 121 and an a interface 122 (the a interface 122 includes a communication interface, a power interface, and an identification signal interface), where the a current-carrying interface 121 has 1 and 2 pins (the 1 pin is correspondingly connected to BAT +, the 2 pin is correspondingly connected to BAT-), the a interface 122 has 1, 2, 3, 4, 5, and 6 pins, where the 1 and 2 pins of the a interface 122 are CAN communication pins (the 1 pin is corresponding to CANH pin, and the 2 pin is corresponding to CANL pin, that is, the 1 and 2 pins are communication interfaces), the 3 and 4 pins of the a interface 122 are VCC power pins (where the 3 pin is connected to VCC, and the 4 pins are grounded, that is, the 3 and 4 pins are grounded, and the 5 and 6 pins of the a interface 122 are identification signal pins (where the 5 pin outputs a 1KHz square wave signal, the duty ratio is 50%, and the 6 pins are grounded, that is, the 5 and 6 pins are identification signal interfaces). The B interface unit 13 includes a B current-carrying interface 131 and a B interface 132 (the B interface 132 includes a communication interface, a power interface and an identification signal interface), where the B current-carrying interface 131 has 1 and 2 pins (the 1 pin is correspondingly connected to BAT +, the 2 pin is correspondingly connected to BAT-), the B interface 132 has 1, 2, 3, 4, 5 and 6 pins, where the 1 and 2 pins of the B interface 132 are CAN communication pins (the 1 pin is corresponding to CANH pin, the 2 pin is corresponding to CANL pin, that is, the 1 and 2 pins are communication interfaces), the 3 and 4 pins of the B interface 132 are VCC power pins (where the 3 pin is VCC, the 4 pin is grounded, that is, the 3 and 4 pins are power interfaces), the 5 and 6 pins of the B interface 132 are identification signal pins (where the 5 pin is grounded, the 6 pin outputs a 1.5KHz square wave signal, and the duty ratio is 50%, that is, the 5 and 6 pins are identification signal interfaces. In this embodiment, the pin 5 of the a interface 122 is connected to the I/O1 interface 111 to output a square wave signal with a duty ratio of 50% and a frequency of 1KHz, and the pin 6 of the B interface 123 is connected to the I/O2 interface 112 to output a square wave signal with a duty ratio of 50% and a frequency of 1.5 KHz. Wherein, the pins 1 and 2 of the a interface 122 are respectively connected with the pins 1 and 2 of the B interface 132 to form a CAN communication bus of the inverter 10, the pins 3 and 4 of the a interface 122 are respectively connected with the pins 3 and 4 of the B interface 132 to form a power bus of the inverter 10, the pins 6 of the a interface 122 and the pins 5 of the B interface 132 CAN be connected with each other because of being grounded, but the pins 5 of the a interface 122 and the pins 6 of the B interface 132 are independent and are not connected with each other.

Referring to fig. 5a and 5b, fig. 5a is a schematic connection diagram of a first battery pack 201, fig. 5b is a schematic connection diagram of a third battery pack 203, and in this embodiment, a wiring structure of a second battery pack 202 is the same as that of the first battery pack 201, and a wiring structure of a fourth battery pack 204 is the same as that of the third battery pack 203. As can be seen from fig. 5a and fig. 5b, each battery pack 20 is respectively provided with a battery control unit 21 and two battery interface units connected to each other (the two battery interface units specifically include a C interface unit 22 and a D interface unit 23), in this embodiment, the battery control unit 21 is specifically a battery pack MCU, and the battery control unit 21 is provided with two battery I/O interfaces (including an I/O3 interface 211 and an I/O4 interface 212). Specifically, the C interface unit 22 includes a C current-carrying interface 221 and a C interface 222 (the C interface 222 includes a communication interface, a power interface and an identification signal interface), the C current-carrying interface 221 has 1 and 2 pins (the 1 pin corresponds to BAT +, the 2 pin corresponds to BAT-), the C interface 222 has 1, 2, 3, 4, 5, and 6 pins (the 1 and 2 pins are communication interfaces, the 3 and 4 pins are power interfaces, and the 5 and 6 pins correspond to BAT-), correspondingly, the D interface unit 23 includes a D current-carrying interface 231 and a D interface 232 (the D interface 232 includes a communication interface, a power interface, and an identification signal interface), the D current-carrying interface 231 has 1 and 2 pins (the 1 pin corresponds to BAT +, the 2 pin corresponds to BAT-), the D interface 232 has 1, 2, 3, 4, 5, and 6 pins (the 1 and 2 pins correspond to BAT-), the 3 and 4 pins are power interfaces, and the 5 and 6 pins are identification signal interfaces); wherein, the 1 and 2 pins of the C interface 222 and the D interface 232 are both CAN communication pins (the 1 pin corresponds to a CANH pin, the 2 pin corresponds to a CANL pin), the 3 and 4 pins of the C interface 222 and the D interface 232 are both VCC power pins, and the 5 and 6 pins of the C interface 222 and the D interface 232 are both identification signal pins; since the C interface unit 22 and the D interface unit 23 are connected to each other, pins 1 and 2 of the C current-carrying interface 221 are correspondingly connected to pins 1 and 2 of the D current-carrying interface 231, respectively, and pins 1, 2, 3, 4, 5, and 6 of the C interface 222 are correspondingly connected to pins 1, 2, 3, 4, 5, and 6 of the D interface 232, respectively.

In which each battery pack 20 is connected to the inverter 10, that is, the C interface unit 22 on the battery pack 20 is directly or indirectly connected to the a interface unit 12 or the B interface unit 13 on the inverter 10, in the present embodiment, as shown in fig. 3, the C interface units 22 on the first battery pack 201 and the second battery pack 202 are directly or indirectly connected to the a interface unit 12 on the inverter 10, and the C interface units 22 of the third battery pack 203 and the fourth battery pack 204 are directly or indirectly connected to the B interface unit 13 on the inverter 10. The specific structure and the subsequent identification method of the energy storage system disclosed by the invention are used for identifying which specific interface unit on the inverter 10 each battery pack is connected with.

In this embodiment, each battery pack 20 is further provided with two isolation units (the two isolation units specifically include a C isolation circuit 24 and a D isolation circuit 25), where the C isolation circuit 24 is connected between pins 5 of the I/O3 interface 211 and the C interface 222, and the D isolation circuit 25 is connected between pins 6 of the I/O4 interface 212 and the D interface 232.

In this embodiment, the I/O1 interface 111 is correspondingly connected to the 5 pins of the a interface 122, and the I/O2 interface 112 is correspondingly connected to the 6 pins of the B interface 123, that is, each of the inverting I/O interfaces (I/O1 interface 111 and I/O2 interface 112) is correspondingly connected to one of the inverting identification signal pins of each of the inverting identification signal interfaces, and the serial numbers of the inverting identification signal pins connected to each of the inverting I/O interfaces are different; in other embodiments, the difference between the identification signals output by the inverting I/O interfaces (I/O1 interface 111 and I/O2 interface 112) may only include the difference between the serial numbers of the inverting identification signal pins connected to the inverting I/O interfaces.

Example two

As shown in fig. 6, the method for identifying an interface between an inverter and a battery pack of an energy storage system disclosed in this embodiment is based on the interface structure and the wiring structure of the inverter and the battery pack of the energy storage system according to the first embodiment, in this embodiment, a pin 5 of an a interface 122 of an inverter 10 outputs a square wave signal with a duty ratio of 50% and a frequency of 1KHz, and a pin 6 is low, and a pin 5 of a B interface 132 outputs a square wave signal with a duty ratio of 50% and a frequency of 1.5KHz, and two types of square waves are adopted, so that there is a frequency difference, so that the inverter 10 can have more data when identifying the battery pack 20, and the result is more accurate, and the specific working steps are as follows:

a1: the inverter establishes communication connection with all the battery packs connected with the inverter;

specifically, the pins 1 and 2 in the a interface 122 of the inverter 10 and the pins 1 and 2 in the B interface 132 are correspondingly connected, so that the pins 1 and 2 in the C interface 222 in the first battery pack 201, the second battery pack 202, the third battery pack 203 and the fourth battery pack 204 are simultaneously and correspondingly connected with the pins 1 and 2 in the a interface 122 and the B interface 132, so that the inverter 10 simultaneously establishes the CAN communication connection with all the battery packs 20.

A2: the inversion control unit respectively generates identification signals through each inversion I/O interface and sends the identification signals to the battery identification signal interfaces of each battery pack through the inversion identification signal interfaces, wherein the identification signals output by each inversion I/O interface are different, and the positions where the identification signals output by each inversion I/O interface are different at least comprise different serial numbers of inversion identification signal pins connected with each inversion I/O interface;

specifically, the inversion control unit 11 generates identification signals through the I/O1 interface 111 and the I/O2 interface 112, respectively, wherein the I/O1 interface 111 generates a square wave signal with a duty ratio of 50% and a frequency of 1KHz, and the I/O2 interface 112 generates a square wave signal with a duty ratio of 50% and a frequency of 1.5 KHz; the I/O1 interface 111 transmits the identification signal (square wave signal with 50% duty ratio and 1KHz frequency) to 5 pins of the C interface 222 and 5 pins of the D interface 232 in the first battery pack 201 and the second battery pack 202 through 5 pins of the a interface 122, and the I/O2 interface 112 transmits the identification signal (square wave signal with 50% duty ratio and 1.5KHz frequency) to 6 pins of the

C interface

222 and 6 pins of the D interface 232 in the third battery pack 203 and the fourth battery pack 204 through 6 pins of the B interface 123.

In the present embodiment, wherein 5 pins of the a interface 122 of the inverter 10 are simultaneously and correspondingly connected with 5 pins of the C interface 222 and 5 pins of the D interface 232 in the first battery pack 201 and the

second battery pack

202, 6 pins of the a interface 122 of the inverter 10 are simultaneously and correspondingly connected with 6 pins of the

C interface

222 and 6 pins of the D interface 232 in the first battery pack 201 and the second battery pack 202; the 5 pins of the B interface 132 of the inverter 10 are simultaneously connected to the 5 pins of the C interface 222 and the 5 pins of the D interface 232 of the third battery pack 203 and the fourth battery pack 204, respectively, and the 6 pins of the B interface 132 of the inverter 10 are simultaneously connected to the 6 pins of the C interface 222 and the 6 pins of the D interface 232 of the third battery pack 203 and the fourth battery pack 204, respectively.

A3: the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal, and sends the interface connection information to the inverter;

specifically, the battery control units 21 of the first battery pack 201 and the second battery pack 202 determine interface connection information between the battery packs and the inverter (the first battery pack 201 and the second battery pack 202 are respectively connected to the a interface unit 12 of the inverter) according to the received identification signal (the square wave signal with the duty ratio of 50% and the frequency of 1 KHz) and the serial numbers (I/O3 interfaces 211) of the battery I/O interfaces corresponding to the received identification signal, and send the interface connection information (the first battery pack 201 and the second battery pack 202 are respectively connected to the a interface unit 12 of the inverter) to the inverter 10. The battery control units 21 of the third battery pack 203 and the fourth battery pack 204 determine interface connection information between the battery pack and the inverter (the third battery pack 203 and the fourth battery pack 204 are respectively connected to the B interface unit 13 of the inverter) according to the received identification signal (the square wave signal with the duty ratio of 50% and the frequency of 1.5 KHz) and the serial number (I/O4 interface 212) of the battery I/O interface corresponding to the received identification signal, and send the interface connection information (the third battery pack 203 and the fourth battery pack 204 are respectively connected to the B interface unit 13 of the inverter) to the inverter 10.

A4: and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack.

The inverter determines that the first battery pack 201 and the second battery pack 202 are respectively connected with the a interface unit 12 of the inverter according to the interface connection information (the first battery pack 201 and the second battery pack 202 are respectively connected with the a interface unit 12 of the inverter), and determines that the third battery pack 203 and the fourth battery pack 204 are respectively connected with the B interface unit 13 of the inverter according to the interface connection information (the third battery pack 203 and the fourth battery pack 204 are respectively connected with the B interface unit 13 of the inverter).

Therefore, in the above steps A3 and A4, the identification step can be directly performed in the following manner: after the I/O3 interface 211 and the I/O4 interface 212 of each battery pack 20 respectively receive the square wave signals with different frequencies, the serial number of the battery I/O interface and the corresponding square wave frequency are returned to the inverter 10 through CAN communication, the I/O3 interface 211 is a 1kHz square wave signal, the I/O4 interface 212 is low level, and the corresponding battery pack is connected with the a interface unit 12 of the inverter 10; the I/O3 interface 211 is at low level, and the I/O4 interface 212 is a 1.5kHz square wave signal, and the corresponding battery pack is connected to the B interface unit 13 of the inverter 10. In some other embodiments, the square wave signals output by the I/O1 interface 111 and the I/O2 interface 112 may also be the same, and the interface units connected to the battery pack can be identified only by the square wave signal or the low level signal, and the square wave signals with different frequencies are used, so that the distinguishing effect can be further enhanced.

In other embodiments, the signal mode may also be a level signal, where a pin 5 of the a interface 122 of the inverter outputs a high level signal and a pin 6 outputs a low level signal, and a pin 5 of the B interface 123 outputs a low level signal and a pin 6 outputs a high level signal; the MCU of each battery pack encodes an I/O interface (for example, defined as I/O3 and I/O4) for receiving the identification signal, after the I/O3 and the I/O4 receive the level, the I/O interface encodes and the level state corresponding to the I/O interface is returned to the inverter through CAN communication, the I/O3 is high level, the I/O4 is low level, and the corresponding battery pack is connected with an A interface 122 (namely, an A interface unit 12) of the inverter; I/O3 is low and I/O4 is high, then the corresponding battery pack is connected to the B interface 132 (i.e., B interface unit 13) of the inverter. Thus, the inverter 10 can receive the interfaces connected to the battery packs 20, and make corresponding actions by judging whether the connection mode of the battery packs meets the preset rules; for example, when the number difference of the battery packs connected with the A/B interface exceeds 1, an alarm prompt is sent out or the output power of the inverter is reduced.

In practical application, the mode of 50% of square wave duty ratio adopted in the embodiment of the invention is more advantageous than the level mode, so that the condition that a receiving circuit device in the battery pack is damaged can be eliminated, the I/O interface of the battery pack MCU receives a certain specific level and is misjudged to be connected with the interface A or the interface B, and the reliability of identification is improved.

In the embodiment, the CAN communication is adopted as the communication mode between the inverter and the battery pack, so that the CAN communication has higher communication speed and more reliable communication quality, and the time required by automatic identification CAN be shortened; and secondly, under the working condition that the number of the inverters is one, the communication between the inverters and the battery pack is more reliable, and meanwhile, the condition of an interface can be identified on line.

After the connection mode of the inverter and the battery pack is identified through the invention, the connection mode is judged to be the first connection mode shown in fig. 1 or a corresponding desired connection mode, the inverter of the energy storage system provides output according to a normal mode, and if the connection mode is not the first connection mode or is not the corresponding desired connection mode (for example, the number difference of the battery packs connected by the interface A and the interface B is more than 1), corresponding derating limit output can be set, and corresponding measures such as abnormal connection prompt alarm and the like are synchronously output to inform a user of correcting the connection mode. The specific workflow steps may be: calculating the number of the battery packs respectively connected to each inversion interface unit in the inverter, calculating the difference value of the number of the battery packs connected to each two inversion interface units, and judging that the inverter provides output for a normal mode if all the difference values are less than or equal to 1; if the difference value is larger than 1, the inverter is judged to provide output for the abnormal mode, and an alarm prompt is sent out or the output power of the inverter is reduced.

Example three:

as shown in fig. 7, an interface structure and a wiring diagram of an energy storage system provided in this embodiment are provided, where the energy storage system includes an inverter 10 and four battery packs 20 (specifically, a first battery pack 201, a second battery pack 202, a third battery pack 203, and a fourth battery pack 204) connected to the inverter 10.

With reference to fig. 8, at the inverter 10 end, the only difference between the first embodiment and the second embodiment is that only 5 pins are respectively disposed on the a interface 122 and the B interface 132, where only one pin is disposed on the identification signal interface, that is, 5 pins are identification signal pins, 5 pins of the a interface 122 correspondingly output a square wave signal with a duty cycle of 50% and a frequency of 1KHz, and 5 pins of the B interface 132 correspondingly output a square wave signal with a duty cycle of 50% and a frequency of 1.5 KHz. And the 5 pin of the a interface 122 is connected to the I/O1 interface 111 to be able to output a square wave signal with a duty ratio of 50% and a frequency of 1KHz, and the 5 pin of the B interface 123 is connected to the I/O2 interface 112 to be able to output a square wave signal with a duty ratio of 50% and a frequency of 1.5 KHz.

It should be noted that, in this embodiment, the interface connected to the battery pack is identified by the different identification signals of the 5 pins of the a interface 122 and the B interface 132, so that, unlike the embodiment, in this embodiment, the difference between the identification signals output by the respective inverted I/O interfaces (I/O1 interface 111 and I/O2 interface 112) includes the difference in frequency of the identification signals, that is, the frequencies of the signals output by the 5 pins of the a interface 122 and the B interface 132 must be different, for example, the signals may be square wave signals with different frequencies, or level signals with different frequencies, or one square wave signal, one level signal, and the like.

Referring to fig. 9a and 9b, fig. 9a is a schematic connection diagram of a first battery pack 201, fig. 9b is a schematic connection diagram of a third battery pack 203, and in this embodiment, the wiring structure of a second battery pack 202 is the same as that of the first battery pack 201, and the wiring structure of a fourth battery pack 204 is the same as that of the third battery pack 203. As can be seen from fig. 9a and 9b, at the end of the battery 20, the present embodiment differs from the first embodiment in the following two points: first, the C interface 222 and the D interface 232 are respectively provided with only 5 pins, wherein the identification signal interface has only one pin, that is, 5 pins are identification signal pins; secondly, in this embodiment, since the identification signal interface has only one pin, correspondingly, the battery control unit 21 only needs to be provided with one battery I/O interface (I/O3 interface 211), and correspondingly, only needs to be provided with one isolation unit (C isolation circuit 24), where the C isolation circuit 24 is connected between the I/O3 interface 211 and the 5 pins of the C interface 222.

Example four

As shown in fig. 10, the method for identifying an interface between an inverter and a battery pack of an energy storage system disclosed in this embodiment is based on the interface structure and the wiring structure of the inverter and the battery pack of the energy storage system in the third embodiment, in this embodiment, a pin 5 of an a interface 122 of the inverter 10 outputs a square wave signal with a duty ratio of 50% and a frequency of 1KHz, and a pin 5 of a B interface 132 outputs a square wave signal with a duty ratio of 50% and a frequency of 1.5KHz, two types of square waves are adopted, and there is a frequency difference, so that the inverter 10 can perform a determination according to frequency data of the received square wave signal when identifying the battery pack 20, and the specific working steps are as follows:

b1: the inverter establishes communication connection with all the battery packs connected with the inverter;

the communication connection in this embodiment is the same as that in the embodiment, and is not described herein again.

B2: the inversion control unit respectively generates identification signals through each inversion I/O interface and sends the identification signals to the battery identification signal interfaces of each battery pack through the inversion identification signal interfaces, wherein the identification signals output by each inversion I/O interface are different, and the different positions of the identification signals output by each inversion I/O interface at least comprise different frequencies of the identification signals respectively generated by each inversion I/O interface;

in this embodiment, the inversion control unit 11 of the inverter 10 generates a square wave signal with a duty ratio of 50% and a frequency of 1KHz through the I/O1 interface 111, and generates a square wave signal with a duty ratio of 50% and a frequency of 1.5KHz through the I/O2 interface 112; since the I/O1 interface 111 is connected to the 5 pins of the a interface 122, the square wave signal generated by the I/O1 interface 111 is sent to the 5 pins of the C interface 222 and the 5 pins of the D interface 232 in the first battery pack 201 and the second battery pack 202 through the 5 pins of the a interface 122; since the I/O2 interface 112 is connected to the 5 pins of the B interface 123, the square wave signal generated by the I/O2 interface 112 is transmitted to the 5 pins of the C interface 222 and the 5 pins of the D interface 232 in the third battery pack 203 and the fourth battery pack 204 through the 5 pins of the B interface 123.

B3: the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the frequency of the received identification signal, and sends the interface connection information to the inverter;

specifically, the battery control units 21 of the first battery pack 201 and the second battery pack 202 determine interface connection information between the battery packs and the inverter (the first battery pack 201 and the second battery pack 202 are respectively connected to the a interface unit 12 of the inverter) according to the received identification signal (a square wave signal having a duty ratio of 50% and a frequency of 1 KHz), and transmit the interface connection information (the first battery pack 201 and the second battery pack 202 are respectively connected to the a interface unit 12 of the inverter) to the inverter 10. The battery control units 21 of the third battery pack 203 and the fourth battery pack 204 determine interface connection information between the battery packs and the inverter (the third battery pack 203 and the fourth battery pack 204 are respectively connected to the B interface unit 13 of the inverter) according to the received identification signals (square wave signals with a duty ratio of 50% and a frequency of 1.5 KHz), and transmit the interface connection information (the third battery pack 203 and the fourth battery pack 204 are respectively connected to the B interface unit 13 of the inverter) to the inverter 10.

B4: the inverter identifies which inversion interface unit of the inverter each battery pack is connected to according to the received identification signal.

Therefore, in the above steps B3 and B4, the I/O1 interface 111 and the I/O2 interface 112 output identification signals with different frequencies, after the I/O3 interface 211 of each battery pack 20 receives the corresponding identification signal, the corresponding identification signal is returned to the inverter 10 through CAN communication, and the inverter determines whether the corresponding battery pack is connected to the a interface unit 12 or the B interface unit 13 of the inverter 10 according to information such as the corresponding frequency of the received identification signal.

After the connection mode of the inverter and the battery pack is identified by the invention, the connection mode is determined to be the first connection mode shown in fig. 1 or a corresponding desired connection mode, the inverter of the energy storage system provides output according to a normal mode, and if the connection mode is not the first connection mode or the corresponding desired connection mode (for example, the difference between the number of the battery packs connected by the interface A and the number of the battery packs connected by the interface B is more than 1), corresponding measures such as derating limit output, synchronous output abnormal connection prompt alarm and the like can be set, so that a user is informed to correct the connection mode. The specific workflow steps may be: calculating the number of battery packs respectively connected to each inversion interface unit in the inverter, calculating the difference value of the number of battery packs connected to every two inversion interface units, and judging that the inverter provides output for a normal mode if all the difference values are less than or equal to 1; if the difference value is larger than 1, the inverter is judged to provide output for the abnormal mode, and an alarm prompt is sent out or the output power of the inverter is reduced.

In the energy storage system disclosed in the first and third embodiments, only two inversion interface units are provided in the inverter 10, and in other embodiments, if three or more inversion interface units are provided in the inverter. The following two schemes can be adopted for setting: first, the identification signal interface in each inversion interface unit in the inverter may also be correspondingly provided with three or more identification signal pins, and correspondingly, the identification signal interface in each battery interface unit in each battery pack may also be correspondingly provided with three or more identification signal pins, and the specific identification method thereof is similar to that in the second embodiment, and is not described herein again; secondly, only one identification signal pin is still arranged on the identification signal interface in each inversion interface unit in the inverter, correspondingly, only one identification signal pin may be arranged on the identification signal interface in each battery interface unit in each battery pack, and only the signals output by the I/O interfaces connected to the identification signal pins of the identification signal interfaces in each inversion interface unit need to be different.

The background of the invention may contain background information related to the problem or environment of the present invention rather than the prior art described by others. Accordingly, the inclusion in this background section is not an admission by the applicant that prior art is available.

The foregoing is a more detailed description of the invention in connection with specific/preferred embodiments and is not intended to limit the practice of the invention to those descriptions. It will be apparent to those skilled in the art that various substitutions and modifications can be made to the described embodiments without departing from the spirit of the invention, and these substitutions and modifications should be considered to fall within the scope of the invention. In the description herein, references to the description of the term "one embodiment," "some embodiments," "preferred embodiments," "an example," "a specific example," or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Moreover, various embodiments or examples and features of various embodiments or examples described in this specification can be combined and combined by one skilled in the art without being mutually inconsistent. Although embodiments of the present invention and its advantages have been described in detail, it should be understood that various changes, substitutions and alterations can be made herein without departing from the scope of the invention as defined by the appended claims.

Claims

1. An energy storage system is characterized by comprising an inverter and a plurality of battery packs connected with the inverter, wherein the inverter is provided with an inversion control unit and at least two inversion interface units, and each battery pack is respectively provided with a battery control unit and two battery interface units connected with each other; the inverter control unit is provided with inverter I/O interfaces with the same number as the inverter interface units, and the battery control unit is provided with battery I/O interfaces;

each inversion interface unit comprises an inversion identification signal interface, each battery interface unit comprises a battery identification signal interface, and when the battery interface unit of the battery pack is connected to one inversion interface unit of the inverter, the battery identification signal interface is correspondingly connected with one inversion identification signal interface;

each inversion I/O interface is correspondingly connected with each inversion identification signal interface respectively, and the battery I/O interface is connected with the battery identification signal interface;

the inverter control unit generates identification signals through the inverter I/O interfaces respectively, and sends the identification signals to the battery identification signal interfaces of the battery packs through the inverter identification signal interfaces, wherein the identification signals output by the inverter I/O interfaces are different;

the battery control unit of each battery pack determines interface connection information of the battery pack and the inverter according to the received identification signal, and sends the interface connection information to the inverter;

and the inverter determines the connection condition of each battery pack and each inversion interface unit according to the interface connection information sent by each battery pack.

2. The energy storage system of claim 1, wherein the inverter identification signal interface comprises an inverter identification signal pin, the battery identification signal interface comprises a battery identification signal pin, the battery identification signal pin is correspondingly connected with the inverter identification signal pin, and the inverter identification signal pin is correspondingly connected with the inverter I/O interface when the battery pack is connected with the inverter; wherein, the difference of the identification signals output by the inverting I/O interfaces at least comprises the difference of the identification signal frequency respectively generated by the inverting I/O interfaces.

3. The energy storage system according to claim 1, wherein the number of the inverter interface units in the inverter is n, the inverter identification signal interface and the battery identification signal interface respectively include n inverter identification signal pins and n battery identification signal pins, the n inverter identification signal pins are respectively a first to an nth inverter identification signal pin, the n battery identification signal pins are respectively a first to an nth battery identification signal pin, and the first to nth inverter identification signal pins are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner; each inversion I/O interface is correspondingly connected with one inversion identification signal pin in each inversion identification signal interface, and the serial numbers of the inversion identification signal pins connected with each inversion I/O interface are different; in the first to nth inversion identification signal pins in each inversion identification signal interface, except the inversion identification signal pin with the corresponding serial number connected with the inversion I/O interface, the inversion identification signal pins with other serial numbers are all grounded, wherein n is an integer greater than or equal to 2, and the difference of the identification signals output by each inversion I/O interface at least comprises the different serial numbers of the inversion identification signal pins connected with each inversion I/O interface.

4. The energy storage system according to claim 3, wherein the battery control unit includes n battery I/O interfaces, the n battery I/O interfaces are respectively a first battery I/O interface to an nth battery I/O interface, and the first battery I/O interface to the nth battery I/O interface are respectively connected to the first battery identification signal pin to the nth battery identification signal pin in a one-to-one correspondence manner.

5. The energy storage system of claim 4, wherein the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

6. The energy storage system of any one of claims 1 to 5, wherein each battery pack is further provided with an isolation unit with the same number of I/O interfaces as the number of the battery I/O interfaces, and each battery I/O interface is connected with the battery identification signal interface through the isolation unit.

7. An identification method for a connection interface between an inverter and a battery pack is applied to the energy storage system of claim 1, and is characterized by comprising the following steps of:

8. The inverter-to-battery pack connection interface recognition method according to claim 7,

the battery pack comprises a battery pack identification signal pin, an inverter I/O interface and an inverter identification signal interface, wherein the inverter identification signal interface comprises an inverter identification signal pin, the battery identification signal pin is correspondingly connected with the inverter identification signal pin when the battery pack is connected with the inverter, and the inverter identification signal pin is correspondingly connected with the inverter I/O interface;

in the step S2, the positions where the identification signals output by the inverting I/O interfaces are different at least include different frequencies of the identification signals respectively generated by the inverting I/O interfaces; and in step S3, the battery control unit of each battery pack determines interface connection information between the battery pack and the inverter according to the frequency of the received identification signal.

9. The method of claim 7, wherein the step of identifying the connection interface between the inverter and the battery pack,

the number of the inversion interface units in the inverter is n, the inversion identification signal interface and the battery identification signal interface respectively comprise n inversion identification signal pins and n battery identification signal pins, the n inversion identification signal pins are respectively first to nth inversion identification signal pins, the n battery identification signal pins are respectively first to nth battery identification signal pins, and the first to nth inversion identification signal pins are respectively connected with the first to nth battery identification signal pins in a one-to-one correspondence manner; each inversion I/O interface is correspondingly connected with one inversion identification signal pin in each inversion identification signal interface, and the serial numbers of the inversion identification signal pins connected with the inversion I/O interfaces are different; in the first to nth inversion identification signal pins in each inversion identification signal interface, except the inversion identification signal pin with the corresponding serial number connected with the inversion I/O interface, the inversion identification signal pins with other serial numbers are all grounded; the battery control unit is provided with n battery I/O interfaces, the n battery I/O interfaces are respectively a first battery I/O interface to an nth battery I/O interface, the first battery I/O interface to the nth battery I/O interface are respectively connected with a first battery identification signal pin to an nth battery identification signal pin in a one-to-one correspondence mode, wherein n is an integer greater than or equal to 2;

in the step S2, the positions where the identification signals output by the inversion I/O interfaces are different at least comprise different serial numbers of the inversion identification signal pins connected with the inversion I/O interfaces; and in step S3, the battery control unit of each battery pack determines the interface connection information between the battery pack and the inverter according to the received identification signal and the serial number of the battery I/O interface corresponding to the received identification signal.

10. The method for identifying the connection interface between the inverter and the battery pack according to any one of claims 7 to 9, further comprising the steps of: calculating the number of the battery packs respectively connected to each inversion interface unit in the inverter, calculating the difference value of the number of the battery packs connected to each two inversion interface units, and if all the difference values are less than or equal to 1, judging that the inverter provides output for a normal mode; and if the difference value is larger than 1, judging that the inverter provides output for the abnormal mode.