WO2022041662A1

WO2022041662A1 - Bms control method and system, electronic device and storage medium

Info

Publication number: WO2022041662A1
Application number: PCT/CN2021/076775
Authority: WO
Inventors: 葛厚艺
Original assignee: 江苏博强新能源科技股份有限公司
Priority date: 2020-08-27
Filing date: 2021-02-19
Publication date: 2022-03-03
Also published as: CN112260359B; CN112260359A

Abstract

The present invention relates to a BMS control method and system, an electronic device, and a storage medium. Said method is used for safety control of a charge and discharge circuit and an external circuit, and comprises the following steps: acquiring a voltage V₁ between an external positive electrode and an external negative electrode and a current I₁ at the external positive electrode or the external negative electrode in the charge and discharge circuit; acquiring a voltage V₂ between an internal positive electrode and an internal negative electrode and a current I₂ at the internal positive electrode or the internal negative electrode in the charge and discharge circuit; and selecting a corresponding control policy according to a real-time state of the charge and discharge circuit, and performing safety control on the charge and discharge circuit and the external circuit on the basis of the voltages V₁ and V₂ and the currents I₁ and I₂. Compared with the prior art, in the present invention, by acquiring currents and voltages inside and outside an BMS and performing safety control on the BMS by means of a corresponding safety control policy, fault determination of a lithium battery, a charge and discharge circuit, a load, etc. can be realized, and the safety of the entire BMS is ensured.

Description

A BMS control method, system, electronic device and storage medium

technical field

The invention belongs to the technical field of battery management, and in particular relates to a BMS control method, system, electronic device and storage medium.

Background technique

The battery management system (BMS, BATTERY MANAGEMENT SYSTEM) is the link between the battery and the user, which can improve the utilization rate of the battery and prevent the battery from being overcharged and overdischarged.

The existing battery management system (BMS) collects relevant battery information (voltage, current, temperature, etc.), controls the charge and discharge MOS after processing by the MCU, cuts off the charge and discharge circuit, and achieves the purpose of protecting the battery, and then passes the dynamic loop monitoring system (FSU) Monitor the status of the battery.

However, the existing technology only samples the voltage and current entering the battery, and only performs simple processing on the collected voltage, current, temperature, etc., and cannot perform comprehensive safety detection, nor can it predict the problems of the battery itself in time, and cannot be completely avoided. security incident.

Therefore, in view of the above technical problems, it is necessary to provide improvements to the existing BMS control technology.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a BMS control method, system, electronic device and storage medium with high control accuracy and comprehensive safety control in order to overcome the above-mentioned defects in the prior art.

The object of the present invention can be realized through the following technical solutions:

A BMS control method, which is used to safely control a charging and discharging circuit and an external circuit, comprising the following steps:

Collect the voltage V ₁ between the external positive electrode and the external negative electrode and the current I ₁ at the external positive electrode or the external negative electrode in the charge-discharge loop;

Collect the voltage V ₂ between the internal positive electrode and the internal negative electrode and the current I ₂ at the internal positive electrode or the internal negative electrode in the charge-discharge loop;

According to the real-time state of the charging and discharging circuit, the corresponding control strategy is selected, and the charging and discharging circuit and the external circuit are safely controlled based on the voltages V ₁ and V ₂ and the currents I ₁ and I ₂ .

Further, the control strategy includes:

In the standby state, the currents I ₁ and I ₂ are 0. When V ₁ ≤ V _UV , the output voltage of the charging and discharging circuit is judged to be abnormal. When V _UV < V ₁ <V _OV and V ₁ ≥ V ₂ , the charging is turned on. When ₁ ≥V _OV , it is determined that the lithium battery is abnormal, where V _UV is the under-voltage protection value of the charging and discharging circuit, V _OV is the over-voltage protection value of the charging and discharging circuit, and V _UV <V _OV ;

In the charging state, when I ₁ >I ₂ , it is determined that the charging and discharging circuit is faulty, and when the variation range of V ₁ is greater than the first preset threshold and reaches the first preset number of times, it is determined that the lithium battery is faulty and the charging is turned off;

In the discharge state, when I ₁ < I ₂ , it is determined that the charging and discharging circuit is abnormal and the discharge is closed; when I ₁ =I ₂ and the variation range of I ₁ is greater than the second preset threshold for a second preset number of times, it is determined that the external load abnormal and turn off the discharge.

Further, when V _UV < V ₁ <V _OV and V ₁ ≥ V ₂ after charging is turned on, if V ₁ < V ₂ +V ₀ , and I ₁ and I ₂ are 0, it is determined that the lithium battery is faulty, and V ₀ is a pre-charge Set the voltage value.

Further, the preset voltage value V ₀ is 0.1V-0.3V.

Further, the preset voltage value V ₀ is 0.2V.

Further, the first preset threshold is greater than or equal to 5V/s, the first preset number of times is greater than or equal to 1 time, the second preset threshold value is greater than or equal to 10V/s, and the second preset number of times is greater than or equal to 10 times .

The present invention also provides a BMS control system for safely controlling the charging and discharging circuit and external circuits, including:

an external data acquisition unit, including a first voltage acquisition unit for acquiring the voltage V ₁ between the external positive electrode and the external negative electrode and a first current acquisition unit for acquiring the current I ₁ at the external positive electrode or the external negative electrode;

an internal data acquisition unit, including a second voltage acquisition unit for acquiring the voltage V ₂ between the internal positive electrode and the internal negative electrode, and a second current acquisition unit for acquiring the current I ₂ at the internal positive electrode or the internal negative electrode;

The BMS control unit is connected to the internal data acquisition unit, the external data acquisition unit and the charging and discharging circuit, and is used to select the corresponding control strategy according to the real-time state of the charging and discharging circuit, and based on the voltages V ₁ , V ₂ and the currents I ₁ , I _2. Safely control the charging and discharging circuit and external circuits.

Further, the control strategy includes:

In the discharge state, when I ₁ <I ₂ , it is determined that the charging and discharging circuit is abnormal and the discharge is closed; when I ₁ =I ₂ and the variation range of I ₁ is greater than the second preset threshold for a second preset number of times, it is determined that the external load abnormal and turn off the discharge.

The present invention also provides an electronic device, comprising:

one or more processors;

memory; and

One or more programs stored in memory, the one or more programs including instructions for executing the BMS control method as described.

The present invention also provides a computer-readable storage medium, comprising one or more programs for execution by one or more processors of an electronic device, the one or more programs including a program for executing any one of claims 1-6 Instructions for the BMS control method.

Compared with the prior art, the present invention has the following beneficial effects:

1. By collecting the internal and external currents and voltages of the charging and discharging circuit, and controlling the BMS system safely through the corresponding security control strategy, fault judgments such as lithium batteries, charging and discharging circuits, and loads can be realized, ensuring the safety of the entire BMS system. sex.

2. Considering the different states of the charging and discharging circuit, such as standby state, charging state, discharging state, etc., and adopting different control strategies for safety control in different states, the accuracy of fault judgment is higher.

3. The method is simple and effective, and can be easily applied to embedded devices.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments described in the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

1 is a schematic diagram of a module of a BMS control system in a specific embodiment of the present invention;

FIG. 2 is a schematic flowchart of a BMS control method in a specific embodiment of the present invention.

detailed description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. This embodiment is implemented on the premise of the technical solution of the present invention, and provides a detailed implementation manner and a specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

Example 1

As shown in FIG. 1 , this embodiment provides a BMS control system for safely controlling a charging and discharging circuit and an external circuit. The charging and discharging circuit includes a lithium battery 10 , a charging unit 21 and a discharging unit 22 , and the charging and discharging circuit includes a lithium battery 10 , a charging unit 21 and a discharging unit 22 . The positive and negative electrodes of the lithium battery are external positive electrodes (P+) and external negative electrodes (P-), and the positive and negative electrodes of lithium batteries are internal positive electrodes (B+) and internal negative electrodes (B-). The BMS control system includes:

The external data acquisition unit includes a first voltage acquisition unit 31 for acquiring the voltage V ₁ between the external positive electrode (P+) and the external negative electrode (P-) and a first current for acquiring the current I ₁ at the external positive electrode or the external negative electrode collection unit 32;

An internal data acquisition unit, including a second voltage acquisition unit 41 for acquiring the voltage V ₂ between the internal positive pole (B+) and the internal negative pole (B-) and a second current for acquiring the current I ₂ at the internal positive pole or the internal negative pole collection unit 42;

The BMS control unit 50 is connected to the internal data acquisition unit, the external data acquisition unit and the charging and discharging circuit, and is used for the safety control of the charging and discharging circuit and the external circuit according to the data collected by the internal data acquisition unit and the external data acquisition unit.

Preferably, the charging unit is a charging MOS tube, and the discharging unit is a discharging MOS tube.

In this embodiment, the first voltage collection unit 31 and the second voltage collection unit 41 directly collect the voltages between the lithium batteries B+ and B- and between the charge and discharge circuits P+ and P-. The first current collection unit 32 and the second voltage collection unit The current collecting unit 42 collects the voltages U ₁ and U ₂ across the resistors R ₁ and R ₂ , and converts them into currents I ₁ and I ₂ flowing through the resistors R ₁ and R ₂ , I ₁ =U ₁ /R ₁ , I ₂ =U ₂ /R ₂ .

Correspondingly, as shown in FIG. 2 , the BMS control method based on current and voltage sampling in this embodiment includes:

S1, collecting the voltage V ₁ between the external positive electrode (P+) and the external negative electrode (P-) and the current I ₁ at the external positive electrode or the external negative electrode in the charging and discharging circuit;

S2, collecting the voltage V ₂ between the internal positive electrode (B+) and the internal negative electrode (B-) and the current I ₂ at the internal positive electrode or the internal negative electrode in the charge-discharge loop;

S3. Select a corresponding control strategy according to the real-time state of the charging and discharging circuit, and perform safety control on the charging and discharging circuit and the external circuit based on the voltages V ₁ and V ₂ and the currents I ₁ and I ₂ .

In this embodiment, the security control policy in step S3 is specifically:

Strategy 1: The BMS control unit is in the standby state (both the charging unit and the discharging unit are turned off), the currents I ₁ and I ₂ are 0, the charging unit and the discharging unit are turned off, and when V ₁ ≤ V _UV , the output voltage of the charging and discharging circuit is determined Abnormal, when V _UV < V ₁ < V _OV and V ₁ ≥V ₂ turns on the charging unit for charging, when V ₁ ≥ V _OV , it is determined that the lithium battery is abnormal, where V _UV is the under-voltage protection value of the charging and discharging circuit, V _OV is the overvoltage protection value of the charging and discharging circuit, and V _UV <V _OV .

In another preferred embodiment, when V _UV < V ₁ <V _OV and V ₁ ≥V ₂ turns on the charging unit for charging, if V ₁ <V ₂ +V ₀ , and I ₁ and I ₂ are 0, it is determined that Lithium battery failure, where V ₀ is the preset voltage value, which is 0.1V-0.3V. The preset voltage value V ₀ in this embodiment is 0.2V.

Strategy 2: The BMS control unit is in the charging state (the charging MOS tube is turned on, and the discharging MOS tube is turned off), when I ₁ >I ₂ , it is determined that the charging and discharging circuit is faulty, and when the variation of V ₁ is greater than the first preset threshold value reaches the first After a preset number of times, it is determined that the lithium battery is faulty and the charging unit is turned off.

Preferably, the first preset threshold is greater than or equal to 5V/s, and the first preset number of times is greater than or equal to 1 time. In this embodiment, the first preset threshold is 5V/s, and the first preset number of times is 1 time.

Strategy 3: The BMS control unit is in the discharge state (discharge MOS tube is turned on, charging MOS tube is turned off), when I ₁ < I ₂ , it is determined that the charging and discharging circuit is abnormal and the discharge unit is closed, when I ₁ =I ₂ and I ₁ changes When the magnitude is greater than the second preset threshold for a second preset number of times, it is determined that the external load is abnormal and the discharge unit is turned off.

Preferably, the second preset threshold is greater than or equal to 10V/s, and the second preset number of times is greater than or equal to 10 times. In this embodiment, the second preset threshold is 10V/s, and the second preset number of times is 10 times.

Further, the voltage and current data collected in the present invention and the state of the charging and discharging circuit, lithium battery, and external circuit determined according to the voltage and current are also reported to the dynamic loop monitoring system (FSU) at the same time, and the FSU is the current state in the BMS control. There are technologies, and details are not repeated here.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically alone, or two or more units may be integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as stand-alone products, may be stored in a computer-readable storage medium. Based on such understanding, the technical solution of the present invention can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, Read-Only Memory (ROM, Read-Only Memory), Random Access Memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes .

Example 2

This embodiment provides a BMS control method for safely controlling a charging and discharging circuit and _an external circuit, including the following steps: collecting the voltage V1 between the external positive electrode and the external negative electrode in the charging and discharging circuit and the voltage V1 between the external positive electrode or the external negative electrode and the external positive electrode or the external negative electrode. current I ₁ ; collect the voltage V ₂ between the internal positive electrode and the internal negative electrode in the charging and discharging loop and the current I ₂ at the internal positive electrode or the internal negative electrode; according to the real-time state of the charging and discharging loop, select the corresponding control strategy, and based on the voltage V ₁ , V ₂ and currents I ₁ and I ₂ perform safety control on the charging and discharging circuit and external circuits. The control strategy is as described in Embodiment 1.

In the BMS control method of this embodiment, the specific parameters of the control strategy are selected as follows: the preset voltage value V ₀ is 0.1V, the first preset threshold value is 8V/s, the first preset number of times is 3 times, and the second preset value is 3 times. The threshold is 12V/s, and the second preset number of times is 15 times.

It will be apparent to those skilled in the art that the present invention is not limited to the details of the above-described exemplary embodiments, but that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments are to be regarded in all respects as illustrative and not restrictive, and the scope of the invention is to be defined by the appended claims rather than the foregoing description, which are therefore intended to fall within the scope of the claims. All changes within the meaning and scope of the equivalents of , are included in the present invention. Any reference signs in the claims shall not be construed as limiting the involved claim.

In addition, it should be understood that although this specification is described according to embodiments, not every embodiment only includes an independent technical solution, and this description in the specification is only for the sake of clarity, and those skilled in the art should take the specification as a whole , the technical solutions in each embodiment can also be appropriately combined to form other implementations that can be understood by those skilled in the art.

Claims

A BMS control method, characterized in that, the method is used to safely control a charging and discharging circuit and an external circuit, comprising the following steps:

Collect the voltage V 1 between the external positive electrode and the external negative electrode and the current I 1 at the external positive electrode or the external negative electrode in the charge-discharge loop;

Collect the voltage V 2 between the internal positive electrode and the internal negative electrode and the current I 2 at the internal positive electrode or the internal negative electrode in the charge-discharge loop;

According to the real-time state of the charging and discharging circuit, the corresponding control strategy is selected, and the charging and discharging circuit and the external circuit are safely controlled based on the voltages V 1 and V 2 and the currents I 1 and I 2 .
The BMS control method according to claim 1, wherein the control strategy comprises:

In the standby state, the currents I 1 and I 2 are 0. When V 1 ≤ V UV , the output voltage of the charging and discharging circuit is judged to be abnormal. When V UV < V 1 <V OV and V 1 ≥ V 2 , the charging is turned on. When 1 ≥V OV , it is determined that the lithium battery is abnormal, where V UV is the under-voltage protection value of the charging and discharging circuit, V OV is the over-voltage protection value of the charging and discharging circuit, and V UV <V OV ;

In the charging state, when I 1 >I 2 , it is determined that the charging and discharging circuit is faulty, and when the variation range of V 1 is greater than the first preset threshold and reaches the first preset number of times, it is determined that the lithium battery is faulty and the charging is turned off;

In the discharge state, when I 1 <I 2 , it is determined that the charging and discharging circuit is abnormal and the discharge is closed; when I 1 =I 2 and the variation range of I 1 is greater than the second preset threshold for a second preset number of times, it is determined that the external load abnormal and turn off the discharge.
The BMS control method according to claim 2, wherein, when V UV < V 1 <V OV and V 1 ≥ V 2 after charging is turned on, if V 1 <V 2 +V 0 , and I 1 , I 2 If it is 0, it is judged that the lithium battery is faulty, and V 0 is the preset voltage value.
The BMS control method according to claim 3, wherein the preset voltage value V 0 is 0.1V-0.3V.
The BMS control method according to claim 4, wherein the preset voltage value V 0 is 0.2V.
The BMS control method according to claim 1, wherein the first preset threshold value is greater than or equal to 5V/s, the first preset number of times is greater than or equal to 1 time, and the second preset threshold value is greater than or equal to 10V/s s, the second preset number of times is greater than or equal to 10 times.
A BMS control system, characterized in that it is used to safely control a charging and discharging circuit and an external circuit, including:

an external data acquisition unit, including a first voltage acquisition unit for acquiring the voltage V 1 between the external positive electrode and the external negative electrode and a first current acquisition unit for acquiring the current I 1 at the external positive electrode or the external negative electrode;

an internal data acquisition unit, including a second voltage acquisition unit for acquiring the voltage V 2 between the internal positive electrode and the internal negative electrode, and a second current acquisition unit for acquiring the current I 2 at the internal positive electrode or the internal negative electrode;

The BMS control unit is connected to the internal data acquisition unit, the external data acquisition unit and the charging and discharging circuit, and is used to select the corresponding control strategy according to the real-time state of the charging and discharging circuit, and based on the voltages V 1 , V 2 and the currents I 1 , I 2. Safely control the charging and discharging circuit and external circuits.
The BMS control system according to claim 7, wherein the control strategy comprises:

In the standby state, the currents I 1 and I 2 are 0. When V 1 ≤ V UV , the output voltage of the charging and discharging circuit is judged to be abnormal. When V UV < V 1 <V OV and V 1 ≥ V 2 , the charging is turned on. When 1 ≥V OV , it is determined that the lithium battery is abnormal, where V UV is the under-voltage protection value of the charging and discharging circuit, V OV is the over-voltage protection value of the charging and discharging circuit, and V UV <V OV ;

In the charging state, when I 1 >I 2 , it is determined that the charging and discharging circuit is faulty, and when the variation range of V 1 is greater than the first preset threshold and reaches the first preset number of times, it is determined that the lithium battery is faulty and the charging is turned off;

In the discharge state, when I 1 < I 2 , it is determined that the charging and discharging circuit is abnormal and the discharge is closed; when I 1 =I 2 and the variation range of I 1 is greater than the second preset threshold for a second preset number of times, it is determined that the external load abnormal and turn off the discharge.
An electronic device, comprising:

one or more processors;

memory; and

One or more programs stored in a memory, the one or more programs comprising instructions for performing the BMS control method of any one of claims 1-6.
A computer-readable storage medium, characterized in that it includes one or more programs for execution by one or more processors of an electronic device, the one or more programs including a program for executing any one of claims 1-6 Instructions for the BMS control method.