阅读说明：本技术 控制电路、方法以及系统 (Control circuit, method and system ) 是由 张龙飞 王兴昌 刘昌鑑 杨大春 余家裕 于 2020-04-09 设计创作，主要内容包括：本发明公开了一种控制电路、方法以及系统。该电路包括使能模块,使能模块的第一端与电池组的正极连接,使能模块的第二端与降压模块的控制信号输入端连接；使能模块用于在确定第一电压小于第一预设电压阈值的情况下,输出第一控制信号至降压模块；第一电压为电池组的正极的电压；第一控制信号用于禁止电压输出端输出电压；降压模块,降压模块的电压输入端与电池组的正极连接,降压模块的电压输出端与电池管理模块连接；电池管理模块用于管理电池组；降压模块用于在接收到第一控制信号的情况下,禁止电压输出端输出电压至电池管理模块。根据本发明实施例,可以避免在电池组对电池管理模块供电的场景下,电池组中的电芯过放。(The invention discloses a control circuit, a method and a system. The circuit comprises an enabling module, wherein the first end of the enabling module is connected with the anode of the battery pack, and the second end of the enabling module is connected with the control signal input end of the voltage reduction module; the enabling module is used for outputting a first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than a first preset voltage threshold; the first voltage is the voltage of the positive pole of the battery pack; the first control signal is used for forbidding the voltage output end to output voltage; the voltage input end of the voltage reduction module is connected with the anode of the battery pack, and the voltage output end of the voltage reduction module is connected with the battery management module; the battery management module is used for managing the battery pack; the voltage reduction module is used for prohibiting the voltage output end from outputting voltage to the battery management module under the condition of receiving the first control signal. According to the embodiment of the invention, the situation that the battery pack supplies power to the battery management module can be avoided, and the over-discharge of the battery cell in the battery pack can be avoided.)

1. A control circuit, the circuit comprising:

the first end of the enabling module is connected with the anode of the battery pack, and the second end of the enabling module is connected with the control signal input end of the voltage reduction module; the enabling module is used for outputting a first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than a first preset voltage threshold; the first voltage is the voltage of the anode of the battery pack; the first control signal is used for forbidding the voltage output end to output voltage;

the voltage input end of the voltage reduction module is connected with the anode of the battery pack, and the voltage output end of the voltage reduction module is connected with the battery management module; the battery management module is used for managing the battery pack; the voltage reduction module is used for prohibiting the voltage output end from outputting voltage to the battery management module under the condition of receiving the first control signal.

2. The circuit of claim 1, wherein a third terminal of the enabling module is connected to the battery management module;

the enabling module is specifically configured to output the first control signal to the voltage reducing module when it is determined that the first voltage is less than the first preset voltage threshold and a second control signal sent by the battery management module is received;

wherein the second control signal is a signal output by the battery management module when it is determined that the acquired first voltage is less than the first preset voltage threshold.

3. The circuit of claim 2, further comprising:

the voltage acquisition module is respectively connected with the voltage output end and the battery management module;

the voltage acquisition module is used for acquiring the first voltage and sending the first voltage to the battery management module.

4. The circuit of claim 1, wherein the enabling module is further configured to output a first enable signal to the voltage dropping module if it is determined that the first voltage is greater than or equal to the first preset voltage threshold; the first enable signal is used for instructing the voltage reduction module to reduce the first voltage to a second voltage and controlling the voltage output end to output the second voltage;

the voltage reduction module is further configured to reduce the first voltage to the second voltage and control the voltage output terminal to output the second voltage to the battery management module when the first enable signal is received.

5. The circuit according to any one of claims 1 to 3, wherein the enabling module is configured to output a second enabling signal to the voltage-reducing module if a third voltage is greater than a second preset voltage threshold, where the third voltage is a preset voltage output by a power supply device externally connected to the fourth terminal of the enabling module; the second enable signal is used for instructing the voltage reduction module to reduce the first voltage into a second voltage and controlling the voltage output end to output the second voltage;

the voltage reduction module is further configured to reduce the first voltage to the second voltage and control the voltage output terminal to output the second voltage to the battery management module when the second enable signal is received.

6. The circuit of claim 5, further comprising:

the voltage acquisition module is respectively connected with the voltage output end and the battery management module;

the voltage acquisition module is further used for acquiring a fourth voltage, the fourth voltage is the voltage of the first end of the switch module, the first end of the switch module is connected with a load, and the second end of the switch module is connected with the anode;

the voltage acquisition module is further used for acquiring a fifth voltage, wherein the fifth voltage is the voltage of the fourth end of the enabling module;

the voltage acquisition module is further used for sending the fourth voltage and the fifth voltage to the battery management module, so that the battery management module controls the switch module to be closed under the condition that the difference value between the fourth voltage and the fifth voltage meets a first preset condition.

7. The circuit of claim 6, wherein the voltage collecting module is further configured to collect the first voltage and send the first voltage to the battery management module, so that the battery management module determines that the switch module fails if it is determined that a difference between the first voltage and the fourth voltage satisfies a second preset condition.

8. A control system comprising the control circuit of any one of claims 1-7 and the battery management module.

9. The control method is applied to a control circuit and is characterized in that the control circuit comprises an enabling module and a voltage reduction module, wherein a first end of the enabling module is connected with the positive electrode of a battery pack, and a second end of the enabling module is connected with a control signal input end of the voltage reduction module; the voltage input end of the voltage reduction module is connected with the anode of the battery pack, and the voltage output end of the voltage reduction module is connected with the battery management module; the battery management module is used for managing the battery pack;

wherein the method comprises the following steps:

the enabling module outputs a first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than a first preset voltage threshold; the first voltage is the voltage of the anode of the battery pack; the first control signal is used for forbidding the voltage output end to output voltage;

the voltage reduction module prohibits the voltage output end from outputting voltage to the battery management module based on the first control signal.

10. The method of claim 9, wherein a third terminal of the enabling module is connected to the battery management module;

wherein, the enabling module outputs a first control signal to the voltage-reducing module when determining that the first voltage is smaller than a first preset voltage threshold, and the enabling module includes:

the enabling module outputs the first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than the first preset voltage threshold and a second control signal sent by the battery management module is received;

wherein the second control signal is a signal output by the battery management module when it is determined that the acquired first voltage is less than the first preset voltage threshold.

11. The method of claim 9, further comprising:

the enabling module outputs a first enabling signal to the voltage reduction module under the condition that the first voltage is determined to be greater than or equal to the first preset voltage threshold; the first enable signal is used for instructing the voltage reduction module to reduce the first voltage to a second voltage and controlling the voltage output end to output the second voltage;

the voltage reduction module reduces the first voltage to the second voltage based on the received first enable signal, and controls the voltage output end to output the second voltage to the battery management module.

12. The method of claim 9, further comprising:

the enabling module outputs a second enabling signal to the voltage reduction module when a third voltage is greater than a second preset voltage threshold, wherein the third voltage is a preset voltage output by a power supply device externally connected to a fourth end of the enabling module; the second enable signal is used for instructing the voltage reduction module to reduce the first voltage into a second voltage and controlling the voltage output end to output the second voltage;

the voltage reduction module reduces the first voltage to the second voltage and controls the voltage output end to output the second voltage to the battery management module under the condition that the second enabling signal is received.

Technical Field

The invention relates to the field of new energy, in particular to a control circuit, a method and a system.

Background

The electric vehicle replaces the fuel vehicle and has become a trend of industry development. The service life and the use safety of the battery pack are particularly important for the use of electric vehicles, and the electric vehicles comprise not only electric vehicles, but also other two-wheeled vehicles, tricycles and the like powered by the battery pack.

Currently, battery packs may be employed to power the battery management modules. However, in the process of supplying power to the battery management module by the battery pack, if the battery cell is over-discharged, irreversible damage to the battery cell may be caused, which greatly affects the service life of the battery cell and the service efficiency of the battery pack.

Disclosure of Invention

The embodiment of the invention provides a control circuit, a method and a system, which can solve the problem of over-discharge of a battery core.

In a first aspect, an embodiment of the present invention provides a control circuit, where the control circuit includes:

the first end of the enabling module is connected with the anode of the battery pack, and the second end of the enabling module is connected with the control signal input end of the voltage reducing module; the enabling module is used for outputting a first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than a first preset voltage threshold; the first voltage is the voltage of the positive pole of the battery pack; the first control signal is used for forbidding the voltage output end to output voltage;

the voltage input end of the voltage reduction module is connected with the anode of the battery pack, and the voltage output end of the voltage reduction module is connected with the battery management module; the battery management module is used for managing the battery pack; the voltage reduction module is used for prohibiting the voltage output end from outputting voltage to the battery management module under the condition of receiving the first control signal.

In a second aspect, an embodiment of the present invention provides a control system, which includes the control circuit and the battery management module as described in the first aspect.

In a third aspect, an embodiment of the present invention provides a control method, which is applied to a control circuit, where the control circuit includes an enabling module and a voltage-reducing module, a first end of the enabling module is connected to a positive electrode of a battery pack, and a second end of the enabling module is connected to a control signal input end of the voltage-reducing module; the voltage input end of the voltage reduction module is connected with the anode of the battery pack, and the voltage output end of the voltage reduction module is connected with the battery management module; the battery management module is used for managing the battery pack;

wherein, the method comprises the following steps:

the enabling module outputs a first control signal to the voltage reduction module under the condition that the first voltage is determined to be smaller than a first preset voltage threshold; the first voltage is the voltage of the anode of the battery pack; the first control signal is used for forbidding the voltage output end to output voltage;

the voltage reduction module prohibits the voltage output end from outputting voltage to the battery management module based on the first control signal.

According to the embodiment of the invention, under the scene that the battery management module is powered by the battery pack, the electric quantity of the battery cell in the battery pack is detected by detecting the first voltage of the anode of the battery pack, in order to prevent the over-discharge of the battery cell, a first preset voltage threshold value is set, when the first voltage is smaller than the threshold value, the electric quantity of the battery cell in the battery pack is less, and if the battery pack continues to discharge, the over-discharge of the battery cell is caused. At this moment, the enabling module outputs the first control signal to the voltage reduction module, and then the voltage reduction module prohibits the voltage output end from outputting voltage based on the first control signal, so that the over-discharge of the battery cell in the battery pack can be avoided, and the service life and the safety of the battery are improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments of the present invention will be briefly described below, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic structural diagram of a control circuit according to a first embodiment of the present invention;

fig. 2 is a schematic structural diagram of a control circuit according to a second embodiment of the present invention;

fig. 3 is a schematic structural diagram of a control circuit according to a third embodiment of the present invention;

fig. 4 is a schematic structural diagram of a control circuit according to a fourth embodiment of the present invention;

fig. 5 is a schematic diagram illustrating a control circuit according to a fifth embodiment of the present invention;

fig. 6 is a schematic structural diagram of a control circuit according to a sixth embodiment of the present invention;

fig. 7 is a flowchart illustrating a control method according to an embodiment of the present invention.

Detailed Description

Features and exemplary embodiments of various aspects of the present invention will be described in detail below, and in order to make objects, technical solutions and advantages of the present invention more apparent, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not to be construed as limiting the invention. It will be apparent to one skilled in the art that the present invention may be practiced without some of these specific details. The following description of the embodiments is merely intended to provide a better understanding of the present invention by illustrating examples of the present invention.

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

At present, a lead-acid storage battery can be used for independently supplying power to a battery management module, and a battery pack is used for supplying power to a load (such as a high-power device like a motor). The battery pack comprises a plurality of battery packs and a battery management module, and in order to simplify the structure of the battery pack and save resources, a special lead-acid storage battery is not required to be arranged for the battery management module to supply power, and the battery packs can be used for supplying power to the battery management module.

However, if the battery management module is powered by the battery pack, there may be a problem of over-discharging of the battery cells in the battery pack, and based on this, embodiments of the present invention provide a control circuit, a method, and a system, where by setting a first preset voltage threshold, when the voltage of the positive electrode of the battery pack is smaller than the threshold, the enabling module outputs a first control signal to the voltage reducing module. The voltage reduction module prohibits the voltage output end from outputting voltage based on the first control signal, namely, the battery pack is prohibited from supplying power to the whole vehicle, so that the over-discharge of the battery cell in the battery pack can be avoided, and the service life and the safety of the battery are improved. The following detailed description is made with reference to the accompanying drawings and examples.

Fig. 1 shows a schematic structural diagram of a control circuit according to a first embodiment of the present invention. As shown in fig. 1, the control circuit includes:

and the first end of the enabling module E is connected with the anode of the battery pack P, and the second end of the enabling module E is connected with the control signal input end of the voltage reducing module D. The enabling module E is configured to output a first control signal to the voltage dropping module D when it is determined that the first voltage is less than the first preset voltage threshold. The first voltage is a voltage of the positive electrode of the battery P. The first control signal is used for forbidding the voltage output end to output the voltage.

And the voltage input end of the voltage reduction module D is connected with the anode of the battery pack P, and the voltage output end of the voltage reduction module D is connected with the battery management module M. The battery management module M is used to manage the battery pack P. The voltage reduction module D is used for prohibiting the voltage output end from outputting voltage to the battery management module M under the condition of receiving the first control signal.

It can be understood that the voltage output end of the voltage-reducing module D also needs to provide working voltage for other electric devices, modules or units of the entire vehicle, and is not limited to providing working voltage for the battery management module M.

It should be noted that, the line connecting the voltage output end of the voltage reduction module D and the battery management module M refers to: and the voltage output end of the voltage reduction module D is connected with a power supply circuit of the battery management module M. That is, the voltage output terminal of the voltage dropping module D may output the voltage VDD to the battery management module M to supply power to the battery management module M. However, if the voltage-reducing module D receives the first control signal, the voltage output terminal is prohibited from outputting VDD to the battery management module M, that is, the battery management module M is no longer powered.

It should be noted that the battery management module M may be used to manage data such as voltage, temperature, fault information, etc. of the battery pack P to monitor the state of the battery pack P. Under the condition that the vehicle stops using or is not used for a long time, the battery management module M can enter a sleep state and can wake up automatically according to the preset time in the sleep state to monitor data.

In some embodiments, the enabling module E may have an acquisition unit and a control unit. The acquisition unit is used for acquiring the voltage of the positive pole (namely P +) of the battery pack P, namely a first voltage. It is worth mentioning that the first voltage represents the sum of the voltages of all the cells inside the battery pack P. The control unit is used for judging whether the first voltage is smaller than a first preset voltage threshold value or not. When the control unit determines that the first voltage is smaller than the first preset threshold, the control unit outputs a first control signal to the voltage reduction module D.

In some embodiments, the first preset voltage threshold is related to an overdischarge threshold voltage of each cell in the battery pack. As an example, the first preset voltage threshold is slightly larger than the sum of the overdischarge threshold voltages of each cell in the battery pack. The over-discharge threshold voltage of the battery cell can be determined based on chemical property parameters of electrolyte of the battery cell and electrical property parameters of a pole of the battery cell.

In other embodiments, the enabling module E may also implement the determination whether the first voltage is smaller than the first preset voltage threshold through a hardware circuit, for example, the determination may be implemented by a voltage comparator.

When the first voltage is lower than the first preset voltage threshold, the enabling module E outputs a first control signal to the voltage-reducing module D, so that the voltage output end of the voltage-reducing module D prohibits outputting the voltage. As one example, the first control signal may be low level.

The overdischarge of the cells in the battery pack P may cause damage to the electrode active material, lose the reaction capability, and shorten the life of the battery. Therefore, in an application scenario where the battery pack P is used to supply power to the battery management module M, in order to prevent the over-discharge of the battery cell, a first preset voltage threshold is set in the present application, and when the first voltage is smaller than the threshold, it indicates that the electric quantity of the battery cell in the battery pack P is less, and if the battery pack P continues to discharge, the over-discharge of the battery cell may be caused. At this time, the enabling module E outputs the first control signal to the voltage-decreasing module D. The voltage reduction module D prohibits the voltage output end from outputting voltage to the battery management module M based on the first control signal, namely, the battery pack P is prohibited from supplying power to the battery management module M, so that the battery management module M enters a dormant state, the over-discharge of the battery cell in the battery pack P can be avoided, and the service life and the safety of the battery are improved.

In the embodiment of the present invention, the battery pack P may supply power not only to the battery management module M but also to a load. Fig. 2 shows a schematic structural diagram of a control circuit according to a second embodiment of the present invention. Referring to fig. 2, the positive pole of the battery pack P is generally connected to one end of a load through a switching module K, and the other end of the load is connected to the negative pole (i.e., P-) of the battery pack P. When the battery pack P is sufficiently charged, the battery pack P can supply power to the battery management module M. When the battery management module M is powered on and then works normally, the battery management module M can control the switch module K to be closed. When the switch module K is closed, the battery pack P can supply power to the load.

However, when the enabling module E determines that the first voltage is less than the first voltage threshold, the enabling module E outputs the first control signal to the voltage dropping module D. The voltage reduction module D prohibits outputting voltage to the battery management module M based on the first control signal, namely, the battery management module M is powered off and enters a dormant state. When the battery management module M enters the sleep state, the switch module K is automatically turned off, and the battery pack P stops outputting externally, that is, stops supplying power to the external load.

Fig. 3 shows a schematic structural diagram of a control circuit according to a third embodiment of the present invention. The difference from the control circuit of fig. 1 is that the enable module E in the control circuit of fig. 3 further has a third terminal, and the third terminal of the enable module E is connected with the battery management module M.

The enabling module E is specifically configured to output the first control signal to the voltage reducing module D when it is determined that the first voltage is less than the first preset voltage threshold and the second control signal sent by the battery management module M is received.

The second control signal is a signal output by the battery management module M when it is determined that the acquired first voltage is smaller than the first preset voltage threshold.

In some embodiments, the battery management module M may itself have the function of collecting the first voltage.

After the battery management module M obtains the first voltage, it is determined whether the first voltage is smaller than a first preset voltage threshold. When the battery management module M determines that the first voltage is smaller than the first preset voltage threshold, the battery management module M determines that the battery cells in the battery pack P are about to be overdischarged. The battery management module M outputs a second control signal to the third terminal of the enable module E.

As one example, the second control signal may be a low level signal.

In order to solve the influence of instability of the voltage of the positive electrode of the battery pack P in a scenario where the battery pack P supplies power to the battery management module M, the accuracy of determining whether the battery cell of the battery pack reaches an overdischarge condition, that is, the accuracy of outputting the first control signal, may be improved by determining whether the acquired first voltage is smaller than the first voltage threshold value by using the battery management module M and the enabling module E, respectively.

When the enabling module E determines that the first voltage is smaller than the first preset voltage threshold and the battery management module M also determines that the first voltage is smaller than the first preset voltage threshold, even if the enabling module E determines that the first voltage is smaller than the first preset voltage threshold and receives the second control signal, it may be determined that the electric core of the battery pack P is about to enter the overdischarge state, and then the first control signal is output to the voltage reducing module D, and the voltage reducing module D does not output voltage externally and does not supply power to the vehicle, and meanwhile, the battery management module M also enters the sleep state, so that the electric core is prevented from entering the overdischarge state.

In the embodiment of the present invention, when the battery management module M determines that the first voltage is smaller than the first voltage threshold, the battery management module M sends a turn-off instruction to the switch module K to turn off the switch module K, so that the battery pack P stops outputting to the outside, and thus the circuit of the electric core in the battery pack P is prevented from being overdischarged. After the battery management module M sends a disconnection command to the switch module K, a second control signal is output to the enable module E, so that the battery management module M enters a sleep state.

Fig. 4 is a schematic structural diagram of a control circuit according to a fourth embodiment of the present invention. The difference with the control circuit of fig. 3 is that the control circuit of fig. 4 further comprises a voltage acquisition module C.

The voltage acquisition module C is respectively connected with the voltage output end and the battery management module M.

The voltage acquisition module C is connected with the positive electrode of the battery pack P and used for acquiring a first voltage and sending the first voltage to the battery management module M.

That is, the battery management module M may obtain the first voltage from the voltage collecting module C. It should be noted that, referring to fig. 4, the dotted line between the battery management module M and the voltage acquisition module C in fig. 4 represents a communication connection therebetween, which may be a wired communication connection or a wireless communication connection.

It should be noted that, the line connecting the voltage output end of the voltage reduction module D and the voltage acquisition module C means: and the voltage output end of the voltage reduction module D is connected with a power supply line of the voltage acquisition module C. That is to say, the voltage output end of the voltage reduction module D can output the voltage VDD to the voltage acquisition module C to supply power to the voltage acquisition module C.

In the embodiment of the present invention, when the electric quantity of the battery pack P is sufficient, the voltage output end of the voltage reduction module D may output the voltage VDD to the battery management module M and the voltage acquisition module C, respectively, so that the battery pack P supplies power to the battery management module M and the voltage acquisition module C.

However, if the voltage-reducing module D receives the first control signal, the voltage output terminal is prohibited from outputting VDD to the battery management module M and the voltage acquisition module C, that is, the battery pack P does not supply power to the battery management module M and the voltage acquisition module C any more.

In the embodiment of the invention, the voltage acquisition module C is used for acquiring the first voltage of the positive electrode of the battery pack P, so that the battery management module M without the function of acquiring the first voltage can be adapted, and the application range is wider.

As can be seen from the above description, in the embodiment of the present invention, it can be determined not only by the enabling module E whether the battery management module M needs to enter the sleep state, but also by the enabling module E and the battery management module M together whether the battery management module M needs to enter the sleep state, so as to avoid the over-discharge of the battery cell in the battery pack P. In other embodiments, the battery management module M may also determine whether it needs to enter the sleep state.

Specifically, the battery management module M may obtain a first voltage of the positive electrode of the battery pack P, and then determine whether the first voltage is less than a first preset voltage threshold. And under the condition that the battery management module M determines that the first voltage is smaller than the first preset voltage threshold, outputting a second control signal to the enabling module E. The enabling module E outputs the first control signal to the voltage reducing module D after receiving the second control signal. After receiving the first control signal, the voltage reduction module D prohibits the voltage output end thereof from supplying power to the battery management module M, thereby preventing the electric core in the battery pack P from being over-discharged.

It should be noted that the battery management module M may acquire the first voltage of the positive electrode of the battery pack P by itself, or may acquire the first voltage of the positive electrode of the battery pack P from the voltage acquisition module C in fig. 4. Under the condition that the battery management module M acquires the first voltage from the voltage acquisition module C, after the voltage reduction module D receives the first control signal, the voltage output end of the voltage reduction module D is forbidden to output the voltage to the battery management module M and the voltage acquisition module C, namely, the battery pack P stops supplying power to the battery management module M and the voltage acquisition module C, and therefore the phenomenon that the battery cells in the battery pack P are overdischarged is avoided.

The specific working process of the control circuit for preventing the over-discharge of the battery cell in the scenario of supplying power to the battery management module M by the battery pack P is described above. The following describes a specific operation process of the control circuit when the battery pack P is used to supply power to the battery management module M when the battery pack P is full.

For any of the control circuits in fig. 1 to 3, the enabling module E is further configured to output a first enabling signal to the voltage dropping module D when the first voltage is determined to be greater than or equal to the first preset voltage threshold. The first enable signal is used for instructing the voltage reduction module D to reduce the first voltage into the second voltage and controlling the voltage output end to output the second voltage.

The voltage reduction module D is further configured to reduce the first voltage to a second voltage and control the voltage output terminal to output the second voltage to the battery management module M when the first enable signal is received.

In the embodiment of the present invention, if the first voltage is greater than or equal to the first preset voltage threshold, it indicates that the electric quantity of the battery pack P is relatively sufficient, and the battery management module M and the load may be continuously powered. The enabling module E outputs a first enabling signal to the voltage reducing module D to supply power to the battery management module M when it is determined that the first voltage is greater than or equal to the first preset voltage threshold.

As one example, if the first control signal is a low level signal, the first enable signal may be a high level signal.

Because the voltage ratio of the battery pack P is high, and the battery management module M generally operates at a low voltage, after receiving the first enable signal, the voltage reduction module D reduces the first voltage of the positive electrode of the battery pack P to the second voltage based on the first enable signal, and outputs the second voltage to the battery management module M through the voltage output terminal to supply power to the battery management module M, i.e., awakens the battery management module M. After the battery management module M is powered on, the switch module K may be controlled to be closed to supply power to the load.

It should be noted that, for the control circuit in fig. 4, when the voltage reduction module D receives the first enable signal, the first voltage is reduced to the second voltage, and the voltage output terminal is controlled to output the second voltage to the battery management module M and the voltage collection module C, respectively.

That is to say, the battery pack P not only supplies power to the battery management module M, but also supplies power to the voltage acquisition module C, so that the voltage acquisition module C can continuously acquire the first voltage, and send the first voltage to the battery management module M, so that the battery management module M determines whether the first voltage is the first preset voltage threshold. That is, the battery management module M monitors whether the electric quantity of the battery pack P reaches the over-discharge condition based on the first voltage, so as to prevent the cells in the battery pack P from being over-discharged.

In some embodiments of the present invention, if the battery management module M enters a sleep state due to a reduction of the power in the battery pack P, the battery pack P needs to be charged in order for the battery pack P to normally supply power to the load and the battery management module M. However, when the battery pack P is to be charged, the battery management module M needs to be awakened so that the battery management module M closes the switch module K, and the battery pack P can be charged by the charging device.

Therefore, in order to wake up the battery management module M in the sleep state to charge the battery pack P, the enabling module E provided by the embodiment of the present invention further has a fourth terminal E4. Fig. 5 is a schematic structural diagram of a control circuit according to a fifth embodiment of the present invention. Referring to fig. 5, the enabling module E has a fourth end E4, and the fourth end E4 can be regarded as a signal access end.

In an embodiment of the invention, the enabling module E is configured to output a second enabling signal to the voltage-reducing module D when the third voltage is greater than a second preset voltage threshold. The third voltage is a preset voltage output by power supply equipment externally connected with a fourth terminal E4 of the enabling module E; the second enable signal is used for instructing the voltage reduction module D to reduce the first voltage into a second voltage and controlling the voltage output end to output the second voltage.

The voltage reduction module D is further configured to reduce the first voltage to a second voltage and control the voltage output terminal to output the second voltage to the battery management module M when the second enable signal is received.

In the embodiment of the present invention, the third voltage may be applied to the enable module E by an external power supply device. As an example, the power supply device may be a power source capable of outputting a fixed voltage, for example, the power supply device may be a charging pile.

After the fourth terminal E4 of the enabling module E receives the third voltage output by the external power supply device, it is determined whether the third voltage is greater than a second preset voltage threshold. If the enabling module E determines that the third voltage is greater than the second preset voltage threshold, a second enabling signal is output to the voltage reducing module D.

It should be noted that the second enable signal may be a high level signal.

If the control circuit does not include the voltage acquisition module C, after the voltage reduction module D receives the second enable signal, the voltage output end of the voltage reduction module D outputs a second voltage to the battery management module M to supply power to the battery management module M, i.e., awaken the battery management module M.

If the control circuit comprises the voltage acquisition module C, the voltage output end of the voltage reduction module D outputs a second voltage to the battery management module M and the voltage acquisition module C so as to supply power to the battery management module M and the voltage acquisition module C, namely, the battery management module M and the voltage acquisition module C are awakened.

When the battery management module M is awakened, that is, after the battery management module M is powered on, the battery management module M controls the switch module K to be closed. Because one end of the charging device is connected with the P +, and the other end of the charging device is connected with the P-, if the switch module K is closed, the charging device can charge the battery pack P.

It should be noted that, during the charging of the battery pack P by the charging apparatus, the voltage of the positive electrode of the battery pack P gradually increases. Therefore, when the voltage of the anode of the battery P is greater than the first preset voltage threshold, the enabling module E outputs the first enabling signal to the voltage-reducing module D. At this time, since the third voltage received by the fourth terminal E4 of the enable module E is also greater than the second preset voltage threshold, the enable module E outputs the second enable signal to the voltage-decreasing module D. When the first voltage is greater than the first preset voltage threshold and the third voltage is greater than the second preset voltage threshold, the first enable signal and the second enable signal may be the same signal.

In the embodiment of the present invention, if the first voltage of the battery P is greater than or equal to the first preset voltage threshold, it indicates that the electric quantity of the battery P is sufficient, and if the battery P is to be used to supply power to the load, it needs to first determine whether the switch module K is normally connected to the external load. And under the condition that the switch module K is normally connected with the external load, the battery management module M controls the switch module K to be closed again so that the battery pack P supplies power to the load.

Whether the external load is normally connected or not can be determined by using the voltage of the fourth terminal E4 of the enable module E and the voltage of the first terminal of the switch module K. The first end of the switch module K is connected with the load, and the second end of the switch module K is connected with the positive pole.

It should be noted that, when charging the battery pack P, it is necessary to output a third voltage to the fourth terminal E4 of the enabling module E by using the external power supply device. However, when the load needs to be supplied with power, the first terminal (i.e., the P + terminal) of the switch module K and the fourth terminal E4 of the enable module E need to be connected to the vehicle-mounted terminal. Therefore, when the load needs to be powered, the fourth terminal E4 of the enable module E is not connected to the voltage output by the external power supply device.

When the external load is normally connected, the external short-circuit device connects the first terminal of the switch module K and the fourth terminal E4 of the enable module E, i.e. the fourth terminal E4 of the enable module E is short-circuited with the first terminal of the switch module K. That is, the difference between the voltage at the fourth terminal E4 of the enable module E and the voltage at the first terminal of the switch module K is within a small voltage difference range.

Therefore, the voltage sampling module may be used to collect the voltage of the fourth terminal E4 of the enable module E and the voltage of the first terminal of the switch module K, and use the difference between the two voltages to determine whether the external load is normally connected to the switch module K.

Referring to fig. 6, the voltage collecting module C is further configured to collect a fourth voltage, where the fourth voltage is a voltage of the first end of the switch module K. The voltage collecting module C is further configured to collect a fifth voltage, where the fifth voltage is a voltage at the fourth terminal E4 of the enabling module E.

The voltage acquisition module C is also used for sending the fourth voltage and the fifth voltage to the battery management module M. After the battery management module M receives the fourth voltage and the fifth voltage, it is determined whether a difference between the fourth voltage and the fifth voltage satisfies a first preset condition, so as to determine whether the external load is normally connected to the switch module K. Under the condition that the battery management module M determines that the difference between the fourth voltage and the fifth voltage meets the first preset condition, the switch module K is controlled to be closed, and then the battery pack P can supply power to the load.

As an example, the first preset condition is that a difference between the fourth voltage and the fifth voltage is within a first preset voltage range.

In the embodiment of the invention, under the working condition that the battery pack P supplies power to the load, before the battery management module M controls the switch module K to be closed, whether the external load is normally connected with the switch module K is judged according to the fourth voltage and the fifth voltage acquired by the voltage acquisition module C, so that the use safety of the battery pack P can be improved.

In some embodiments of the present invention, before the battery pack P is charged by the charging device, the battery management module M needs to control the switch module K to be closed, and in order to improve the safety of charging the battery pack P, it is necessary to determine whether the switch module K is already closed, that is, determine whether the switch module K fails.

In some embodiments of the present invention, referring to fig. 6, the voltage collecting module C is further configured to collect a first voltage and a fourth voltage, and send the first voltage and the fourth voltage to the battery management module M, so that the battery management module M determines that the switch module K fails when it is determined that a difference between the first voltage and the fourth voltage satisfies a second preset condition.

If the battery management module M determines that the difference between the first voltage and the fourth voltage meets the second preset condition, it represents that the switch module K is not normally closed, and it represents that the switch module K has a fault, and the battery management module M may output fault information of the switch module K to remind a user that the switch module K has a fault and the battery pack P cannot be charged.

After the battery management module M receives the first voltage and the fourth voltage, if it is determined that the difference between the first voltage and the fourth voltage does not satisfy the second preset condition, it represents that the switch module K is normally closed, and it represents that the charging state of the battery pack P is normal.

As an example, the second preset condition may be that a difference between the first voltage and the fourth voltage is not within a second preset voltage range.

In the embodiment of the invention, in the process of charging the battery pack P, whether the switch module K has a fault is judged by utilizing the difference value between the first voltage and the fourth voltage acquired by the battery acquisition module and the second preset condition, so that the charging state of the battery pack P can be timely reminded to a user, and the user can be timely reminded when the switch module K has a fault.

The embodiment of the invention also provides a control system, which comprises the control circuit and the battery management module M.

For a specific implementation manner of the control system, reference may be made to the description part of the control circuit, and details are not described herein.

Fig. 7 is a flow chart of a control method according to some embodiments of the present invention, which is used in the control circuits shown in fig. 1 to fig. 6. The control method provided by the embodiment of the invention comprises the following steps:

in step 710, the enabling module E outputs a first control signal to the voltage-reducing module D when it is determined that the first voltage is smaller than the first preset voltage threshold. The first voltage is the voltage of the anode of the battery pack P; the first control signal is used for indicating the voltage output end to stop outputting the voltage.

In step 720, the voltage-reducing module D controls the voltage output terminal to stop outputting the voltage to the battery management module M based on the first control signal.

According to the embodiment of the invention, under the scene that the battery pack P is used for supplying power to the battery management module M, the quantity of electric quantity of a battery cell in the battery pack P is detected by detecting the first voltage of the anode of the battery pack P, in order to prevent the over-discharge of the battery cell, a first preset voltage threshold value is set, when the first voltage is smaller than the threshold value, the electric quantity of the battery cell in the battery pack P is less, and if the battery pack P continues to discharge, the over-discharge of the battery cell can be caused. At this moment, the enabling module E outputs a first control signal to the voltage reducing module D, and then the voltage reducing module D prohibits the voltage output end from outputting voltage to the battery management module M based on the first control signal, so that the battery management module M is prohibited from being powered by the battery pack P, and the battery management module M is made to sleep, thereby preventing the electric core in the battery pack P from being over-discharged, and improving the service life and safety of the battery.

In some embodiments of the present invention, in order to improve the accuracy of determining whether the battery cell is about to generate the over-discharge of the electric quantity, the third end of the enabling module E is connected to the battery management module M; wherein, step 710 includes:

the enabling module E outputs a first control signal to the voltage reducing module D when determining that the first voltage is less than the first preset voltage threshold and receiving a second control signal sent by the battery management module M.

The second control signal is a signal output by the battery management module M when it is determined that the acquired first voltage is smaller than the first preset voltage threshold.

In some embodiments of the present invention, the control method provided in the embodiments of the present invention further includes:

in step 730, the enabling module E outputs a first enabling signal to the voltage decreasing module D when it is determined that the first voltage is greater than or equal to the first preset voltage threshold. The first enable signal is used for instructing the voltage reduction module D to reduce the first voltage into the second voltage and controlling the voltage output end to output the second voltage.

In step 740, the voltage reduction module D reduces the first voltage to a second voltage based on the received first enable signal, and controls the voltage output terminal to output the second voltage to the battery management module M.

It should be noted that, if the battery pack P has enough power during the initial use, step 730 and step 740 may be executed before step 710.

When the voltage of the positive electrode of the battery P is greater than the first preset voltage threshold after the battery P is charged, the steps 730 and 740 may also be performed after the step 720.

In some embodiments of the present invention, the control method provided in the embodiments of the present invention further includes:

in step 750, the enabling module E outputs a second enabling signal to the voltage reducing module D when the third voltage is greater than the second preset voltage threshold.

The third voltage is a preset voltage output by a power supply device externally connected to the fourth terminal E4 of the enable module E. The second enable signal is used for instructing the voltage reduction module D to reduce the first voltage into a second voltage and controlling the voltage output end to output the second voltage.

In step 760, the voltage reducing module D reduces the first voltage to a second voltage and controls the voltage output terminal to output the second voltage to the battery management module M when receiving the second enable signal.

It should be noted that, steps 750 and 760 may be executed after step 720, that is, when the battery pack P has a low capacity, that is, when the battery management module M is in a sleep state, the preset voltage output by the external power supply device connected to the fourth terminal E4 of the enabling module E may be used to wake up the battery management module M so as to charge the battery pack P.

It should be clear that the embodiments in this specification are described in a progressive manner, and the same or similar parts in the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. For the control method embodiments, reference may be made to the description of the control circuit for relevant points. The present invention is not limited to the specific steps and structures described above and shown in the drawings. Those skilled in the art may make various changes, modifications and additions or change the order between the steps after appreciating the spirit of the invention. Also, a detailed description of known process techniques is omitted herein for the sake of brevity.

As will be apparent to those skilled in the art, for convenience and brevity of description, the specific working processes of the systems, modules and units described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again. It should be understood that the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive various equivalent modifications or substitutions within the technical scope of the present invention, and these modifications or substitutions should be covered within the scope of the present invention.