CN108656976B

CN108656976B - Battery management system

Info

Publication number: CN108656976B
Application number: CN201710212128.8A
Authority: CN
Inventors: 郭富强; 李帅
Original assignee: Beijing Hyperstrong Technology Co Ltd
Current assignee: Beijing Hyperstrong Technology Co Ltd
Priority date: 2017-04-01
Filing date: 2017-04-01
Publication date: 2021-04-13
Anticipated expiration: 2037-04-01
Also published as: CN108656976A

Abstract

The present invention provides a battery management system, comprising: a processor, a power circuit and a switch circuit; the processor is respectively connected with the power circuit and the switch circuit, and the switch circuit is connected between the power circuit and the low-voltage power supply; the switching circuit is used for conducting the connection between the power supply circuit and the low-voltage power supply when the wake-up signal is detected, and waking up the BMS to enter a normal working state; the processor is used for controlling the switch circuit to disconnect the power circuit from the low-voltage power supply when the wake-up signal is detected to disappear, so that the BMS enters a sleep state. According to the BMS provided by the invention, the switching circuit can automatically identify the signal input to the switching circuit, the connection between the power supply circuit and the low-voltage power supply is switched on or off, the automatic control of the awakening and sleeping of the BMS and the normal-fire power supply of the BMS are realized, and the influence of the abnormal-fire power supply mode on the BMS can be avoided while the power consumption of the system is reduced.

Description

Battery management system

Technical Field

The invention relates to a battery management technology, in particular to a battery management system, and belongs to the technical field of electric automobiles.

Background

With the rapid increase of the number of new energy automobiles in the automobile industry in China, the attention of consumers on electric automobiles is higher and higher. The battery is used as a core component in the electric automobile, and the safety performance of the battery is particularly important. Currently, a Battery Management System (BMS) is adopted in the market to monitor and manage the state of a Battery in real time.

On an electric vehicle, a BMS is typically powered by a low voltage power supply on the vehicle. When each item function of BMS was opened completely, the consumption was great, if the vehicle did not use for a long time, and BMS was in operating condition always, then consumed the electric quantity of low voltage power easily, led to electric automobile unable normal start when next use. Therefore, when the electric vehicle is not used for a long time, the electric vehicle needs to enter a sleep state to reduce system power consumption.

On present electric automobile, BMS and low voltage power supply generally adopt very fiery connected mode when being connected, and BMS inserts low voltage power supply through the switch in the car, controls BMS's power supply through the key switch of vehicle promptly. When the vehicle key is started, the BMS is electrified and works, and the BMS enters a normal working state; after the vehicle is flamed out, the BMS is powered down, and the BMS enters a dormant state. When the power battery of vehicle need charge, for the BMS power supply by filling the rifle that charges on the electric pile, awaken up BMS and get into normal operating condition.

However, when the charging gun is used for charging, the abnormal fire connection method often causes the phenomenon that the supply voltage of the BMS is inconsistent with that of the charging gun, so that the normal use of the BMS is influenced.

Disclosure of Invention

In view of this, the present invention provides a battery management system, which can automatically control the operating state of a BMS, and can reduce the power consumption of the system and avoid the influence of a very hot power supply mode on the BMS by using a hot power supply mode.

To achieve the above object, the present invention provides a battery management system BMS including: a processor, a power circuit and a switch circuit; the processor is respectively connected with the power circuit and the switch circuit, and the switch circuit is connected between the power circuit and the low-voltage power supply;

the switching circuit is used for conducting the connection between the power supply circuit and the low-voltage power supply when the wake-up signal is detected, and waking up the BMS to enter a normal working state;

the processor is used for controlling the switch circuit to disconnect the power circuit from the low-voltage power supply when the wake-up signal is detected to disappear, so that the BMS enters a sleep state.

In an embodiment of the present invention, the wake-up signal includes: controller area network CAN signals and/or hard-wired signals.

In an embodiment of the invention, the switching circuit is further configured to: when the vehicle is in a flameout state and the voltage value of the low-voltage power supply is detected to be smaller than a first preset voltage, the connection between the power supply circuit and the low-voltage power supply is conducted, so that the processor controls the power battery to charge the low-voltage.

In an embodiment of the invention, the processor is further configured to: and when the voltage value of the low-voltage power supply is detected to be equal to the second preset voltage, the switch circuit is controlled to disconnect the power supply circuit from the low-voltage power supply.

In an embodiment of the present invention, the BMS further includes: a timing circuit; the timing circuit is respectively connected with the switch circuit and the low-voltage power supply, and the timing circuit is used for sending a conducting signal to the switch circuit according to first preset time when the vehicle is in a flameout state, so that the switch circuit conducts connection between the power supply circuit and the low-voltage power supply according to the conducting signal.

In an embodiment of the invention, the timing circuit is further configured to send an off signal to the switching circuit according to a second preset time after sending the on signal, so that the switching circuit disconnects the power supply circuit from the low-voltage power supply according to the off signal.

In one embodiment of the invention, the timing circuit is integrated on the processor.

According to the BMS provided by the embodiment of the invention, the switching circuit can automatically identify the signal input to the switching circuit, the connection between the power supply circuit and the low-voltage power supply is switched on or off, the automatic control of the awakening and sleeping of the BMS and the normal-fire power supply of the BMS are realized, and the influence of the abnormal-fire power supply mode on the BMS can be avoided while the power consumption of the system is reduced.

Drawings

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

fig. 2 is a schematic view illustrating a flow direction of BMS signals provided by the present invention;

fig. 3 is a schematic structural diagram of a BMS according to a second embodiment of the present invention.

Description of reference numerals:

10-a processor;

20-a power supply circuit;

30-a switching circuit;

40-a low voltage power supply;

50-an in-vehicle switch;

60-a vehicle control unit;

70-timing circuit.

Detailed Description

Aiming at the technical problems that the conventional BMS is generally connected with a low-voltage power supply by adopting an abnormal fire connection mode, and the normal use of the BMS is influenced due to the fact that the power supply voltage of the BMS is inconsistent with the power supply voltage of the charging gun when the charging gun is used for charging, the embodiment of the invention provides the BMS.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

Fig. 1 is a schematic structural diagram of a first BMS provided by the present invention, and as shown in fig. 1, the BMS provided by the present embodiment includes: a processor 10, a power supply circuit 20, and a switch circuit 30; the processor 10 is respectively connected with the power circuit 20 and the switch circuit 30, and the switch circuit 30 is connected between the power circuit 20 and the low-voltage power supply 40; the switching circuit 30 is used for conducting the connection between the power circuit 20 and the low voltage power supply 40 when detecting the wake-up signal, and waking up the BMS to enter a normal working state; the processor 10 is configured to control the switch circuit 30 to disconnect the power circuit 20 from the low voltage power source 40 when the wake-up signal is detected to disappear, so that the BMS enters a sleep state.

Specifically, the processor 10 may be a Micro Controller Unit (MCU), and the power circuit 20 is used to power various circuits in the BMS by power supplied from a low voltage power supply 40 on the vehicle. When the power circuit 20 is connected to the low voltage power source 40, the entire BMS enters a normal operating state, and the processor 10 can control various circuits in the BMS to monitor and manage the power battery.

The switch circuit 30 is connected between the power supply circuit 20 and the low-voltage power supply 40, and can control on/off between the power supply circuit 20 and the low-voltage power supply 40. When the BMS enters the sleep state, the low voltage power supply 40 supplies power to the switching circuit 30, and the switching circuit 30 may be connected to an in-vehicle switch, a vehicle controller, a charging interface, etc. in the vehicle to detect the wake-up signal. When the switching circuit 30 detects the wake-up signal and wakes up the BMS by turning on the connection between the power circuit 20 and the low voltage power supply 40, the BMS enters a normal operating state and the processor 10 starts to operate normally; when the processor 10 detects that the wake-up signal disappears, a control signal may be sent to the switching circuit 30 to control the switching circuit 30 to disconnect the power circuit 20 from the low voltage power source 40, so that the BMS enters a sleep state. The wake-up signal may specifically include: controller Area Network (CAN) signals and/or hard-wired signals, etc.

Fig. 2 is a schematic flow diagram of BMS signals according to the present invention, in which a switching circuit 30 is connected to an in-vehicle switch 50 and a vehicle controller 60 in a vehicle, and a wake-up signal includes a CAN signal and a hard-wire signal for exemplary illustration.

The operating principle of the BMS shown in fig. 2 is specifically: when the vehicle is started in a flameout state, the vehicle controller 60 and the switch 50 on the vehicle start to work to respectively generate a CAN signal and a hard-wire signal; when the switching circuit 30 detects a CAN signal or a hard wire signal (wake-up signal), the connection between the power supply circuit 20 and the low voltage power supply 40 is turned on, the power supply circuit 20 operates, and the entire BMS enters a normal operating state. When the vehicle is flamed out, the vehicle controller 60 and the in-vehicle switch 50 on the vehicle stop working, and the CAN signal and the hard wire signal disappear; when the processor 10 detects that the CAN signal or the hard wire signal disappears, it sends a control signal to the switch circuit 30, controls the switch circuit 30 to disconnect the power circuit 20 from the low voltage power supply 40, stops the power circuit 20, and the whole BMS enters a sleep state, at which time the switch circuit 30 continues to detect whether there is a wake-up signal.

In the above fig. 2, the hard wire signal is generated as the in-vehicle switch 50, and the hard wire signal may be inputted to the BMS from the outside of the vehicle, for example, when the vehicle is charged by the charging post, the charging gun may generate the hard wire signal. In addition, the wake-up signal may be other signals for waking up the BMS, and the embodiment is not particularly limited.

In this embodiment, switching circuit can automatic identification input to its signal, switches on or cuts off the connection between power supply circuit and the low voltage power supply, realizes waking up the automatic control with the dormancy to can not use for a long time at the vehicle, control BMS gets into the dormancy state, with reduction system power consumption. And, BMS realizes the automatic control of BMS power supply through its inside switch circuit, directly links between BMS and the low voltage power supply (adopt the normal fire power supply mode promptly), when adopting the rifle that charges to charge the power battery of vehicle, BMS can be according to the hard wire signal (awakening signal) of the rifle that charges automatic awakening BMS entering normal operating condition, and BMS is supplied power by the low voltage power supply always, therefore does not have BMS and the inconsistent phenomenon of rifle supply voltage that charges to can avoid producing the influence to BMS.

The BMS that this embodiment provided, switch circuit can automatic identification input to its signal, switches on or cuts off the connection between power supply circuit and the low voltage power supply, realizes awakening the automatic control with the dormancy and the normal fire power supply of BMS to BMS, can avoid the influence that the power supply mode of abnormal fire produced BMS when reducing system's consumption.

Fig. 3 is a schematic structural diagram of a second BMS embodiment according to the present invention, which is a further optimization supplement to the embodiment shown in fig. 1. As shown in fig. 3, on the basis of the embodiment shown in fig. 1, the BMS provided by the present embodiment further includes: a timing circuit 70; the timing circuit 70 is connected to the switching circuit 30 and the low voltage power source 40, respectively, and the timing circuit 70 is configured to send a turn-on signal to the switching circuit 30 according to a first preset time when the vehicle is in a key-off state, so that the switching circuit 30 turns on the connection between the power source circuit 20 and the low voltage power source 40 according to the turn-on signal. The timing circuit 70 is further configured to send an off signal to the switching circuit 30 according to a second preset time after sending the on signal, so that the switching circuit 30 disconnects the power circuit 20 from the low voltage power source 40 according to the off signal.

Specifically, when the vehicle was not used for a long time, BMS was in the power failure state (promptly dormancy state) all the time, if power battery had abnormal conditions when this period, BMS can not timely detection to can have certain risk. In this embodiment, the timing circuit 70 is added in the BMS, and when the vehicle is in a flameout state for a long time, the timing circuit 70 can send a conduction signal to the switching circuit 30 at a timing according to a set first preset time, so that the switching circuit 30 conducts the connection between the power supply circuit 20 and the low voltage power supply 40 according to the conduction signal, thereby waking up the BMS to monitor the state of the power battery and solving the risk problem caused by the long-time power failure of the BMS.

When the timing circuit 70 finishes sending the on signal, and the BMS monitors the power battery for a period of time (a second preset time), the timing circuit 70 may send an off signal to the switching circuit 30 again, so that the switching circuit 30 disconnects the connection between the power circuit 20 and the low voltage power supply 40 according to the off signal, and the BMS enters a sleep state to save energy.

It should be noted that the on signal and the off signal may be repeatedly transmitted, that is, when the vehicle is not used for a relatively long time, the timing circuit 70 may transmit the on signal to the switch circuit 30 every first preset time, and transmit the off signal to the switch circuit 30 after a second preset time elapses after each transmission of the on signal. The first preset time and the second preset time may be specifically set according to needs, and this embodiment is not particularly limited. As with the switching circuit 30, the timing circuit 70 may be powered by the low voltage power supply 40, consuming a small amount of power.

In addition, the timing circuit 70 may be integrated on the processor 10, that is, the processor 10 sends the on signal and the off signal to the switch circuit 30 at regular time. In specific implementation, if the existing processor has a timing function, the timing function can be directly added to the processor; otherwise, a processor-independent timing circuit 70 may be additionally provided in the BMS, and may be specifically set as needed.

As an optional implementation manner, in this embodiment, the switch circuit 30 is further configured to: when the vehicle is in a flameout state and the voltage value of the low-voltage power supply 40 is detected to be smaller than the first preset voltage, the connection between the power supply circuit 20 and the low-voltage power supply 40 is conducted, so that the processor 10 controls the power battery to charge the low-voltage. The processor 10 is further configured to: when detecting that the voltage value of the low-voltage power supply 40 is equal to the second preset voltage, the control switch circuit 30 disconnects the power supply circuit 20 from the low-voltage power supply 40.

Specifically, when the vehicle was not used for a long time, the BMS was in the power down state all the time, and the state of low voltage power supply 40 can not be confirmed to the BMS, and if the low voltage power supply 40 for the BMS power supply was when undervoltage, then the BMS can not in time charge to low voltage power supply 40 to the start-up of vehicle may be influenced. In this embodiment, when the vehicle is in a flameout state, the switch circuit 30 may detect the magnitude of the voltage value of the low voltage power supply 40 supplying power to the switch circuit, when the voltage value is smaller than a first preset voltage (for example, the normal operating voltage is 12V, the first preset voltage may be 10V), the connection between the power circuit 20 and the low voltage power supply 40 is conducted, the power circuit 20 of the BMS operates, the whole BMS enters the normal operating state, the processor 10 may detect that the voltage value of the low voltage power supply 40 is lower in real time, at this time, the power battery may be controlled to charge the low voltage power supply 40, and the power is timely supplemented to the low voltage power supply 40, so as to avoid affecting the start-up of the vehicle.

When the processor 10 detects that the voltage value of the low voltage power supply 40 is equal to a second preset voltage (e.g., 13V), it may send a control signal to the switching circuit 30, and control the switching circuit 30 to disconnect the power circuit 20 from the low voltage power supply 40, so that the BMS enters a sleep state to save energy.

The BMS that this embodiment provided, through timing circuit and switch circuit, can in time detect the abnormal condition of battery and the undervoltage condition of low voltage power supply when the vehicle does not use for a long time, avoid the long-time system of BMS to fall the influence that the electricity brought.

Those of ordinary skill in the art will understand that: all or a portion of the steps of implementing the above-described method embodiments may be performed by hardware associated with program instructions. The program may be stored in a computer-readable storage medium. When executed, the program performs steps comprising the method embodiments described above; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and the modifications or the substitutions do not make the essence of the corresponding technical solutions depart from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A Battery Management System (BMS), comprising: a processor, a power circuit and a switch circuit; the processor is respectively connected with the power circuit and the switch circuit, and the switch circuit is connected between the power circuit and a low-voltage power supply;

the switching circuit is used for conducting the connection between the power circuit and the low-voltage power supply when a wake-up signal is detected, and waking up the BMS to enter a normal working state;

the processor is used for controlling the switch circuit to disconnect the power circuit from the low-voltage power supply when the wake-up signal disappears, so that the BMS enters a sleep state;

the switching circuit is connected with an in-vehicle switch, a vehicle controller and a charging interface of the vehicle to detect the awakening signal;

the wake-up signal comprises: a controller area network CAN signal and/or a hard wire signal;

the switching circuit is further configured to: when the vehicle is in a flameout state and the voltage value of the low-voltage power supply is detected to be smaller than a first preset voltage, the connection between the power circuit and the low-voltage power supply is conducted, so that the processor controls the power battery to charge the low-voltage;

the processor is further configured to: and when the voltage value of the low-voltage power supply is detected to be equal to a second preset voltage, controlling the switch circuit to disconnect the power supply circuit from the low-voltage power supply.

2. The BMS of claim 1, further comprising: a timing circuit; the timing circuit is respectively connected with the switch circuit and the low-voltage power supply, and the timing circuit is used for sending a conducting signal to the switch circuit according to first preset time when a vehicle is in a flameout state, so that the switch circuit conducts connection between the power supply circuit and the low-voltage power supply according to the conducting signal.

3. The BMS of claim 2, wherein the timing circuit is further configured to send an off signal to the switching circuit according to a second preset time after sending the on signal to cause the switching circuit to disconnect the power circuit from the low voltage power supply according to the off signal.

4. The BMS of claim 2 or 3, wherein the timing circuit is integrated on the processor.