CN211908396U

CN211908396U - Multi-group lithium battery pack parallel charging and discharging control system

Info

Publication number: CN211908396U
Application number: CN202020140810.8U
Authority: CN
Inventors: 吕天远
Original assignee: Wuxi Sumnergy Technology Co ltd
Current assignee: Wuxi Sumnergy Technology Co ltd
Priority date: 2020-01-21
Filing date: 2020-01-21
Publication date: 2020-11-10
Anticipated expiration: 2030-01-21

Abstract

The utility model discloses a charging and discharging control system with multiple groups of lithium battery packs connected in parallel, which belongs to the technical field of battery management and comprises a main control module, a communication network group module, a charging and discharging control loop module and an identity identification module, the communication network group module comprises two groups of CAN communication networks, each CAN communication network consists of an internal CAN communication network and an external CAN communication network, a plurality of external CAN communication networks are connected in parallel with each other on the communication networks of the charger and external loads, a plurality of internal CAN communication networks are connected in parallel with each other to form an independent communication circuit, the internal CAN communication network and the external CAN communication network are isolated from each other, on the basis of not adding any additional module, the communication network group module automatically identifies whether the current battery pack is in a single-group operation state or a parallel operation state, and respectively controls charging and discharging.

Description

Multi-group lithium battery pack parallel charging and discharging control system

Technical Field

The utility model relates to a battery management technical field specifically is a parallelly connected charge-discharge control system of multiunit lithium cell package.

Background

The capacity and the output power are used as important evaluation indexes of the quality of the lithium battery pack and become key factors for restricting the vigorous development of the electric motorcycle and the electric scooter gradually. In order to solve the above two problems, most of the car factories increase the capacity and output power of the battery pack by increasing the number of parallel batteries inside the battery pack. However, the method not only increases the cost, but also easily causes the capacity and output power overflow of other vehicle types, and has low flexibility. Meanwhile, some manufacturers use a distributed system to connect multiple groups of batteries in parallel through an optimized circuit design, but the method needs an additional central control system to control charging and discharging of multiple groups of battery packs, and is also too high in cost and needs additional space to install the central control system.

SUMMERY OF THE UTILITY MODEL

This section is for the purpose of summarizing some aspects of embodiments of the invention and to briefly introduce some preferred embodiments. Some simplifications or omissions may be made in this section and in the abstract of the specification and the title of the application to avoid obscuring the purpose of this section, the abstract of the specification and the title of the application, and such simplifications or omissions are not intended to limit the scope of the invention.

The present invention has been made in view of the above and/or other problems occurring in the conventional charge and discharge control system.

Therefore, the utility model aims at providing a parallelly connected charge-discharge control system of multiunit lithium cell package can not increase on the basis of any extra module, organizes the module automatic identification through communication network and shows that present group battery is in singly organizing the operation or the parallelly connected state of operation of multiunit group battery to carry out charge-discharge control respectively to this.

For solving the technical problem, according to the utility model discloses an aspect, the utility model provides a following technical scheme:

the utility model provides a parallelly connected charge-discharge control system of multiunit lithium cell package, includes host system, communication network group module, charge-discharge control circuit module and identification module, communication network group module includes two sets of CAN communication networks, CAN communication network comprises inside CAN communication network and outside CAN communication network, and is a plurality of outside CAN communication network connects in parallel each other on the communication network of machine of charging and external load, and is a plurality of inside CAN communication network connects in parallel each other and is independent communication line, inside CAN communication network and outside CAN communication network mutual isolation.

As a preferred scheme of parallelly connected charge-discharge control system of multiunit lithium cell package, wherein: the communication network group module also comprises an interface for accessing and awakening.

As a preferred scheme of parallelly connected charge-discharge control system of multiunit lithium cell package, wherein: and the plurality of charging and discharging control loops are mutually connected in parallel on the output loop of the charger or an external load.

As a preferred scheme of parallelly connected charge-discharge control system of multiunit lithium cell package, wherein: the identity identification module is independently arranged on a communication network group module of a single battery pack.

Compared with the prior art: the beneficial effects in this document are as follows:

(21) the parallel charging and discharging control system of the multiple groups of lithium battery packs automatically identifies the running state of the current battery pack, not only can realize the single-group running of the battery packs, but also supports the parallel running of the multiple groups of battery packs, improves the universality of the battery packs and reduces the weight of the single battery pack;

(2) the charging and discharging control system for the multiple groups of lithium battery packs in parallel determines whether each battery pack meets the charging and discharging conditions according to the working state of each battery pack, so that the phenomenon of energy transfer among the battery packs is avoided, and the safety and the reliability of the battery packs are improved;

(3) when the battery pack is in a state that the plurality of groups of battery packs are connected in parallel (not awakened), after the battery management system is awakened, the multi-group lithium battery pack parallel charging and discharging control system can automatically identify and distribute identity information of each group of battery packs, the flexibility of the battery packs is improved by the strategy, each battery pack can be a host or a slave, and the parallel operation of the plurality of groups of battery packs is realized on the premise of not adding additional equipment;

(4) when the battery pack is in single-group operation (awakened), other battery packs are connected at the moment, the multi-group lithium battery pack parallel charging and discharging control system automatically identifies the connection state of other battery packs and automatically switches to the multi-group battery pack parallel operation state;

(5) when the battery pack is in a state of parallel operation (awakened) of the multiple groups of battery packs, the connection of other battery packs is disconnected at the moment, and the parallel charging and discharging control system of the multiple groups of lithium battery packs automatically identifies the connection states of other battery packs and automatically switches to a single group operation state.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the present invention will be described in detail with reference to the accompanying drawings and detailed embodiments, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive labor. Wherein:

fig. 1 is a schematic diagram of a system structure of a parallel charging and discharging control system for multiple groups of lithium battery packs according to the present invention;

fig. 2 is the utility model relates to a parallelly connected charge-discharge circuit schematic diagram of charge-discharge control system of multiunit lithium cell package.

Detailed Description

In order to make the above objects, features and advantages of the present invention more comprehensible, embodiments of the present invention are described in detail below with reference to the accompanying drawings.

In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention, but the present invention may be implemented in other ways than those specifically described herein, and one skilled in the art may similarly generalize the present invention without departing from the spirit of the present invention, and therefore the present invention is not limited to the specific embodiments disclosed below.

Next, the present invention will be described in detail with reference to the schematic drawings, and in the detailed description of the embodiments of the present invention, for convenience of explanation, the sectional view showing the device structure will not be enlarged partially according to the general scale, and the schematic drawings are only examples, and should not limit the scope of the present invention. In addition, the three-dimensional dimensions of length, width and depth should be included in the actual fabrication.

In order to make the objects, technical solutions and advantages of the present invention clearer, embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.

The utility model provides a parallelly connected charge-discharge control system of multiunit lithium cell package please refer to figure 1, including host system, communication network group module, charge-discharge control circuit module and identification module, communication network group module includes two sets of CAN communication network, CAN communication network comprises inside CAN communication network and outside CAN communication network, and is a plurality of outside CAN communication network connects in parallel each other on the communication network who charges machine and external load, and is a plurality of inside CAN communication network connects in parallel each other and is independent communication line, inside CAN communication network and outside CAN communication network are kept apart each other.

Referring to fig. 1 again, the communication network module further includes an interface for wake-up access.

Referring to fig. 1 again, a plurality of the charge and discharge control loops are connected in parallel to the output loop of the charger or the external load.

Referring again to fig. 1, the identification module is a communication network module separately installed on a single battery pack.

In the specific use process: the method comprises the following steps: connecting a plurality of groups of battery packs together in parallel, connecting the battery packs to an external load or a charger, and awakening the plurality of groups of battery packs through connecting an awakening interface; step two: after the multiple groups of battery packs are awakened, the multiple groups of lithium battery packs are connected in parallel with the charge-discharge control system to perform identity recognition through an internal CAN communication network and an identity recognition module, and a host and a slave in the multiple groups of battery packs are distinguished, wherein only one host is provided, and one or more slave CAN be provided; step three: after the host is identified, the host reads the battery pack voltage, current, fault state and other information of other slave machines through an internal CAN communication network, and determines which battery packs of the plurality of battery packs can be discharged according to the information, when discharging, the host machine firstly shields the battery packs which can not be discharged due to faults, selecting the battery pack with the highest battery voltage from the rest battery packs for discharging, when the voltage of the battery pack with the highest voltage is reduced to the voltage of the battery pack with the next highest voltage to be consistent, the next highest voltage battery is also discharged, and in such a ratio, the battery that cannot be charged due to a failure is first shielded during charging, then, the charging MOS of all the rechargeable battery packs are opened, and when each battery pack confirms the charging information and then opens the discharging MOS, the charging and discharging loop can avoid the energy transfer problem caused by inconsistent battery voltage during charging, as shown in FIG. 2; step four: after the host is identified, only the host CAN communicate with the charger or an external load through an external CAN communication network, and the host integrates the information of all the battery packs and integrates the information and sends the information to the charger and the external load; step five: when the battery pack is in single-group operation and is awakened, no matter the identity information identified by the identity identification module of the battery pack is a host or a slave, the battery pack is forcibly set as the host, if other battery packs are connected, the multi-group lithium battery pack parallel charging and discharging control system automatically identifies that other battery packs are connected through an internal CAN communication network, at the moment, the battery packs connected later are forcibly set as the slave, no matter the identity information identified by the identity identification module of the battery packs is the host or the slave, and all the battery packs are automatically switched into a multi-group battery pack parallel operation state; step six: when the battery pack is in a state that the multiple groups of battery packs are in parallel operation, namely the battery pack is awakened, if the connection of the slave battery packs is disconnected at the moment, the multi-group lithium battery pack parallel charging and discharging control system automatically identifies the connection state of the slave battery packs through an internal CAN communication network, the host machine automatically switches to a single group operation state, the external output of the multiple groups of battery packs is kept in the middle of switching, and the slave machine disconnects the external output.

The parallel charging and discharging control method of the multiple groups of battery packs is divided into five states according to the functional requirements: initialization, standby, charge, discharge, and off states. And designing a multi-group battery pack parallel charging and discharging control strategy and each state transition strategy through stateflow, and establishing a multi-group battery pack parallel charging and discharging control model according to the strategies. And after the modeling is completed, verifying each state switching. After the verification is finished, a code is generated through Simulink.

While the invention has been described above with reference to an embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In particular, as long as there is no structural conflict, the various features of the disclosed embodiments of the present invention can be used in any combination with each other, and the non-exhaustive description of these combinations in this specification is merely for the sake of brevity and resource conservation. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the appended claims.

Claims

1. The utility model provides a parallelly connected charge-discharge control system of multiunit lithium cell package which characterized in that: the intelligent charging and discharging system comprises a master control module, a communication network group module, a charging and discharging control loop module and an identity recognition module, wherein the communication network group module comprises two groups of CAN communication networks, each CAN communication network consists of an internal CAN communication network and an external CAN communication network, the external CAN communication networks are connected in parallel with each other on the communication networks of a charger and an external load, the internal CAN communication networks are connected in parallel with each other to form an independent communication line, and the internal CAN communication networks are isolated from the external CAN communication networks.

2. The system of claim 1, wherein the system comprises: the communication network group module also comprises an interface for accessing and awakening.

3. The system of claim 1, wherein the system comprises: and the plurality of charging and discharging control loops are mutually connected in parallel on the output loop of the charger or an external load.

4. The system of claim 1, wherein the system comprises: the identity identification module is independently arranged on a communication network group module of a single battery pack.