Battery pack parallel system

Abstract

The utility model discloses a battery pack parallel connection system which comprises a direct current bus, a DC-DC converter, a battery pack and a monitor. The DC-DC converter is arranged between the direct current bus and the battery pack; the plurality of battery packs are connected in parallel; and the DC-DC converter is in communication connection with the monitor. Based on the battery pack parallel system in the technical scheme, the influence of the wooden barrel effect of a single battery pack and the high coupling degree between the battery packs on the whole battery pack is greatly reduced, the service life of the battery packs is prolonged, waste of battery resources is reduced, and meanwhile the problem that batteries of different manufacturers cannot be compatible is solved.

Description

Technical Field

[0001] The present application relates to the technical field of battery charging and discharging, and in particular to a battery pack parallel system. Background Art

[0002] With the advancement of technology and the development of social informatization, the stability of power systems, the continuity of communication networks, and the uninterrupted operation of important facilities such as data centers are becoming increasingly important. The performance and capacity status of battery packs as backup power sources directly determine the emergency response capabilities and sustained operation capabilities of these systems.

[0003] The backup battery packs of the traditional DC power supply system are connected in series, so the capacity of the entire battery pack is determined by the battery pack with the smallest capacity. Due to the different internal resistance of the batteries, the voltage of the battery pack with a lower capacity will be higher than the general voltage during charging, and it is easier to be fully charged. On the contrary, the battery pack with a higher capacity is not easy to be fully charged. Therefore, when the total voltage remains unchanged, the high-capacity battery pack will often not be fully charged, and the low-capacity battery pack will often be overcharged, going to two extremes at the same time. Although the rectifier will regularly balance the battery pack. However, since the entire group is balanced, it still cannot completely solve the problem of individual batteries lagging behind. In actual operation, if a group of batteries has a problem, it is often necessary to replace all the batteries on the same DC bus, resulting in a relatively large waste.

[0004] In view of this, a new technical solution is urgently needed to solve the above technical problems. Utility Model Content

[0005] The main purpose of the present application is to provide a battery pack parallel system, aiming to solve the technical problem that the existing battery pack system has a high degree of coupling and is prone to waste battery resources.

[0006] To achieve the above objectives, the battery pack parallel connection system proposed in this application includes:

[0007] DC bus, DC-DC converter, battery pack and monitor;

[0008] The DC-DC converter is arranged between the DC bus and the battery pack;

[0009] A plurality of the battery packs are connected in parallel;

[0010] The DC-DC converter is communicatively connected to the monitor.

[0011] Optionally, the battery pack parallel system further includes:

[0012] Backend terminal;

[0013] The monitor is in communication connection with the background terminal.

[0014] Optionally, the monitor is connected to the backend terminal via RJ45 communication.

[0015] Optionally, the battery pack parallel system further includes: a DC load;

[0016] The DC load is connected in parallel with the DC-DC converter on the DC bus.

[0017] Optionally, the battery pack includes a plurality of single cells connected in series.

[0018] Optionally, the single battery is electrically connected to a battery collection module.

[0019] Optionally, a plurality of the battery collection modules are cascaded to form a battery collection module group.

[0020] Optionally, the battery collection module group is electrically connected to the battery pack management module.

[0021] Optionally, the battery pack management module is communicatively connected to the monitor.

[0022] Optionally, the battery pack management module is connected to the monitor via RS485 communication.

[0023] The beneficial effects of the present application are as follows: by setting a matching DC-DC converter between each DC bus and each battery pack in the battery pack parallel system of the present application, the number of battery packs in parallel can be increased and the number of battery packs in series can be reduced. The DC-DC converter steps down the voltage from the DC bus to the battery pack to fully charge the battery, and steps up the voltage from the battery pack to the DC bus to fully supply power to the load and discharge the battery, which greatly reduces the influence of the barrel effect of a single battery pack and the high coupling degree between battery packs on the entire battery pack, thereby increasing the service life of the battery pack and reducing the waste of battery resources. At the same time, it also solves the problem of incompatibility between batteries from different manufacturers. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying any creative work.

[0025] Figure 1 A schematic diagram of the battery pack parallel system structure of the battery pack of the present application and in connection with a unified embodiment;

[0026] Figure 2 A schematic diagram of charging a battery pack of the present application and in connection with a unified embodiment;

[0027] Figure 3 A discharge schematic diagram of a battery pack of the present application and in connection with a unified embodiment.

[0028] Description of Figure Numbers:

[0029] Label name Label name 1 DC bus 2 DC-DC Converters 3 Battery Pack 4 Battery Management Module 5 Monitor 6 Backstage terminal

[0030] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] It should be noted that all directional indications in the embodiments of the present application (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0033] In addition, the descriptions of "first", "second", etc. in this application are only for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, "and / or" in the full text includes three solutions. Taking A and / or B as an example, it includes technical solution A, technical solution B, and technical solution that satisfies both A and B; in addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by this application.

[0034] Please refer to Figure 1 to Figure 3 As shown in the figure, the battery pack parallel system includes:

[0035] DC bus 1, DC-DC converter 2, battery pack 3 and monitor 5;

[0036] The DC-DC converter 2 is arranged between the DC bus 1 and the battery pack 3;

[0037] A plurality of battery packs 3 are connected in parallel;

[0038] The DC-DC converter 2 is in communication connection with the monitor 5 .

[0039] In this embodiment, the voltage at one end of the DC-DC converter 2 connected to the DC bus 1 is consistent with the voltage of the DC bus 1, and the voltage at one end connected to the battery pack 3 can be determined according to the number of batteries connected in series in the corresponding battery pack 3. Generally, the voltage level of the battery pack 3 is ≤ the voltage of the DC bus 1.

[0040] The DC-DC converter 2 is arranged between the DC bus 1 and the battery pack 3, so that multiple battery packs 3 can be connected in parallel, thereby replacing the traditional connection mode of multiple battery packs 3 in series. If there are N battery packs 3, there are N DC-DC converters 2, that is, one battery pack 3 is connected to one DC-DC converter 2, so that each battery pack 3 can correspond to a different DC-DC converter 2 based on the different voltages, so that each battery pack 3 can be charged and discharged evenly, and there will be no situation where some battery packs 3 are overcharged and some battery packs 3 are undercharged. The battery pack 3 includes a plurality of single cells connected in series.

[0041] The DC-DC converter 2 is connected to the monitor 5 for communication. The monitor 5 has an electrical signal acquisition module and an electrical signal transmission module, which can detect the battery parameters such as the current, voltage, internal resistance, capacity and temperature of the battery pack 3. When the battery needs to be charged, the monitor 5 can use the DC-DC converter 2 to draw power from the DC bus 1 and step down the voltage to charge the battery pack 3 sequentially or simultaneously; when the capacity needs to be increased or the DC bus 1 loses power, the DC-DC converter 2 will increase the voltage, and the battery pack 3 will supply power to the DC load on the DC bus 1. The DC-DC converter 2 and the monitor 5 can be connected to each other for communication via a CAN (Controller Area Network) bus.

[0042] By setting a matching DC-DC converter 2 between each DC bus 1 and each battery pack 3 in the battery pack parallel system of the present application, the number of battery packs 3 connected in parallel can be increased and the number of battery packs 3 connected in series can be reduced. The DC-DC converter 2 steps down the voltage from the DC bus 1 to the battery pack 3 to fully charge the battery, and steps up the voltage from the battery pack 3 to the DC bus 1 to fully supply power to the load and discharge the battery, which greatly reduces the influence of the barrel effect of a single battery group and the high coupling degree between the battery groups 3 on the entire battery group, thereby increasing the service life of the battery group 3 and reducing the waste of battery resources. At the same time, it also solves the problem of incompatibility between batteries from different manufacturers.

[0043] Optionally, in one embodiment, the battery pack parallel system further includes:

[0044] Backstage terminal 6;

[0045] The monitor 5 is in communication connection with the background terminal 6 .

[0046] The background terminal 6 can be a data processing terminal such as a server, a computer, or a smart phone. By connecting the monitor 5 to the background terminal 6, various operating parameters of the battery pack parallel system can be remotely monitored and controlled in the background. For example, the monitor 5 can send the monitored battery parameters such as the current, voltage, internal resistance, capacity, and temperature of the battery pack 3 to the background for remote monitoring. For another example, the entire charging, discharging, and capacity verification process can be executed remotely in the background. For this embodiment, the efficiency of operation and maintenance is greatly improved by remotely verifying the capacity and discharging and charging of multiple groups of batteries in parallel. The operation and maintenance personnel do not need to go to the site to connect the wires, but only need to operate in the background, saving a lot of time and cost. Among them, the monitor 5 can be connected to the background terminal 6 through an RJ45 interface.

[0047] It should be pointed out that the capacity test of traditional batteries is usually carried out through offline discharge tests, which require regular on-site manual inspections to evaluate the health status and actual charge capacity of the battery. However, this method is time-consuming, inefficient, has a long test cycle, and has certain damage to the battery itself (frequent deep discharge may cause accelerated battery aging), and cannot reflect the actual working status of the battery in real time. In addition, as the number of batteries and battery capacity increase, the cost and difficulty of manual maintenance also increase.

[0048] Optionally, in one embodiment, the battery pack parallel system further includes: a DC load;

[0049] The DC load is connected in parallel with the DC-DC converter 2 and is arranged on the DC bus 1 .

[0050] For this embodiment, the remote nuclear capacitor discharge load is an actual load, which saves energy to a certain extent compared with the dummy load used in the traditional offline nuclear capacitor.

[0051] Optionally, in one embodiment, the single battery is electrically connected to a battery collection module.

[0052] The purpose of such a design is to enable the battery acquisition module to monitor the health status and working condition of each single battery, so as to detect battery abnormalities in a timely manner and avoid adverse effects on the battery pack 3 and the entire system.

[0053] Optionally, in one embodiment, a plurality of the battery collection modules are cascaded to form a battery collection module group.

[0054] It is also called that the single cell sampling modules corresponding to each group of batteries are connected hand in hand, which can be regarded as a serial communication connection method.

[0055] Optionally, in one embodiment, the battery collection module group is electrically connected to the battery group management module 4 .

[0056] The battery pack management module 4 is in communication connection with the monitor 5 .

[0057] In this embodiment, each battery group can be uniformly managed by the corresponding battery group management module 4, and the battery group management module 4 can summarize the battery information monitored by the battery collection module group and send it to the monitor 5. The battery group management module 4 is connected to the monitor 5 via RS485 communication.

[0058] The above description is only a preferred embodiment of the present application, and does not limit the patent scope of the present application. All equivalent structural changes made by using the contents of the present application specification and drawings under the application concept of the present application, or directly / indirectly used in other related technical fields are included in the patent protection scope of the present application.

Claims

1. A battery pack parallel system, characterized in that: The battery pack parallel system comprises: DC bus, DC-DC converter, battery pack and monitor; The DC-DC converter is arranged between the DC bus and the battery pack; A plurality of the battery packs are connected in parallel; The DC-DC converter is communicatively connected with the monitor; The battery pack includes a plurality of single cells connected in series; The single battery is electrically connected to the battery collection module.

2. The battery pack parallel system according to claim 1, characterized in that: The battery pack parallel system also includes: Backend terminal; The monitor is in communication connection with the background terminal.

3. The battery pack parallel connection system according to claim 2, characterized in that: The monitor is connected to the backend terminal via RJ45 communication.

4. The battery pack parallel system according to claim 1, characterized in that: The battery pack parallel system also includes: a DC load; The DC load is connected in parallel with the DC-DC converter on the DC bus.

5. The battery pack parallel connection system according to claim 1, characterized in that: A plurality of the battery collection modules are cascaded to form a battery collection module group.

6. The battery pack parallel connection system as claimed in claim 5, characterized in that: The battery collection module group is electrically connected to the battery group management module.

7. The battery pack parallel connection system according to claim 6, characterized in that: The battery pack management module is in communication connection with the monitor.

8. The battery pack parallel connection system according to claim 7, characterized in that: The battery pack management module is connected to the monitor via RS485 communication.

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