CN211223102U

CN211223102U - Bidirectional wake-up circuit of battery management system, battery management system and electric vehicle

Info

Publication number: CN211223102U
Application number: CN201922494541.5U
Authority: CN
Inventors: 曲洁; 常一鸣; 杨亚坤; 沈卫林
Original assignee: Svolt Energy Technology Co Ltd
Current assignee: Svolt Energy Technology Co Ltd
Priority date: 2019-12-31
Filing date: 2019-12-31
Publication date: 2020-08-11
Anticipated expiration: 2029-12-31

Abstract

The utility model relates to a battery management system technical field discloses a two-way wake-up circuit of battery management system, battery management system and electric vehicle. The bidirectional wake-up circuit comprises a main board, N slave boards and N signal transmission circuits; the N slave boards are connected in series through a daisy chain circuit, and detection signals are transmitted between the slave boards and between the Nth slave board and the master board through the signal transmission circuit. The utility model can wake up the slave plate through the master plate and can wake up the master plate through the slave plate, under the dormant state of the master plate, the slave plate can be automatically woken up periodically, the slave plate directly collects and judges the battery state information, and the collection of the monomer is convenient and flexible; the mainboard is awakened only when the slave board judges that the battery state is abnormal, so that the power consumption of the whole battery management system is reduced; the slave board can still monitor the battery state and process in time when the mainboard sleeps, and the thermal runaway phenomenon appears when avoiding the mainboard dormancy, has improved battery system security.

Description

Bidirectional wake-up circuit of battery management system, battery management system and electric vehicle

Technical Field

The utility model relates to a battery management system technical field particularly, relates to a two-way awakening circuit of battery management system, a battery management system and an electric vehicle.

Background

The battery is one of the key components of the electric automobile, and the battery management system bms (battery management system) can monitor information such as temperature, voltage, current and the like of the battery pack in a normal working state, alarm and process in time when the battery pack is out of control due to heat, and transmit the alarm information to a vehicle control unit (vcu) of the whole vehicle controller to avoid natural or explosion of the battery.

When the BMS is in a dormant state, the related information of the battery pack cannot be monitored, and the BMS needs to be awakened for monitoring. Fig. 1 is a schematic diagram of a BMS wake-up manner of the prior art, as shown in fig. 1, the BMS includes a master board BCU and a slave board CMC, and there are two wake-up manners of the BMS master board: one is a power chip connected to the BMS mainboard through an engine ignition signal KL15, the BMS mainboard is awakened when the KL15 signal is high level, and the BMS enters a sleep state when software sends a sleep command; the other is that CANH and CANL of a CAN signal of the vehicle controller are respectively connected to two pins of a BMS mainboard power chip, the BMS mainboard is awakened when the CAN transmits an awakening instruction, and the BMS enters dormancy when a VCU of the vehicle controller sends a dormancy instruction. The existing BMS awakening mode is that the slave board is awakened by the master board, namely the master board BCU sends an awakening signal, data acquisition is started after the slave board CMC receives the signal, the master board BCU sends a dormancy instruction, the slave board CMC enters dormancy after receiving the instruction, and the slave board CMC cannot acquire information such as voltage, current and temperature of the battery pack at the moment.

The existing BMS awakening mode is unidirectional, and only a mainboard BCU (battery management unit) can awaken a slave board CMC (battery management controller), so that the following defects are realized: when the BMS is in sleep, if data acquisition is required, the main board BCU is required to be awakened first to send an information acquisition instruction, and the information acquisition steps are redundant; data acquisition cannot be directly controlled by the slave CMC, the state of a battery pack when the BMS is dormant cannot be monitored, and thermal runaway cannot be timely handled; the mainboard BCU awakens up and consumes the electric energy of the storage battery of the whole vehicle, so that the storage battery is insufficient.

SUMMERY OF THE UTILITY MODEL

The utility model aims at providing a two-way awakening circuit of battery management system to overcome the defect of foretell one-way awakening mode.

In order to achieve the above object, a first aspect of the present invention provides a bidirectional wake-up circuit for a battery management system, including a motherboard, N slave boards, and N signal transmission circuits; the N slave plates are sequentially connected through a daisy chain circuit, and detection signals are transmitted between the slave plates and between the Nth slave plate and the master plate through the signal transmission circuit; wherein N is a positive integer.

Furthermore, the signal transmission circuit comprises a photoelectric coupler and a current-limiting resistor, and the input end of the photoelectric coupler is connected with the current-limiting resistor.

Furthermore, the signal transmission circuit further comprises a bypass capacitor, one end of the bypass capacitor is connected with the input end of the photoelectric coupler and the current-limiting resistor, and the other end of the bypass capacitor is grounded.

Furthermore, the mainboard comprises a microcontroller, a power chip and an isolation network transceiver, wherein the power chip supplies power to the microcontroller, and the microcontroller is connected with the daisy chain circuit through the isolation network transceiver.

Furthermore, a current-limiting resistor of a signal transmission circuit between the nth slave board and the master board is connected with a signal output end of the nth slave board, and an output end of a photoelectric coupler of the signal transmission circuit between the nth slave board and the master board is connected with the power supply chip and a general input/output interface of the microcontroller.

Further, a photoelectric coupler and a power supply chip of a signal transmission circuit between the Nth slave board and the main board are powered by a storage battery.

Furthermore, a current limiting resistor of a signal transmission circuit between the first slave board and the second slave board is connected with a general input/output interface of the microcontroller, and an output end of a photoelectric coupler of the signal transmission circuit between the first slave board and the second slave board is connected with a signal input end of the first slave board.

Further, in the master board sleep state, the slave board can be automatically awakened periodically through a program instruction.

The utility model discloses the second aspect provides a battery management system, including the two-way awakening circuit of foretell battery management system.

A third aspect of the present invention provides an electric vehicle including the above battery management system.

The utility model discloses embodiment provides a two-way wake-up circuit not only can awaken up the slave plate through the mainboard, can awaken up the mainboard through the slave plate moreover. The slave board can be automatically awakened periodically in a sleeping state of the main board, the slave board directly acquires and judges the battery state information, the state of each single battery is conveniently acquired, and the acquisition mode is flexible; the mainboard is awakened only when the slave board judges that the battery state is abnormal, so that the power consumption of the whole battery management system is reduced; the slave board can still monitor the battery state and process in time when the mainboard sleeps, and the thermal runaway phenomenon appears when avoiding the mainboard dormancy, has improved battery system security.

Other features and advantages of embodiments of the present invention will be described in detail in the detailed description which follows.

Drawings

The accompanying drawings, which are included to provide a further understanding of the embodiments of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the embodiments of the invention, but do not constitute a limitation of the embodiments of the invention. In the drawings:

fig. 1 is a schematic diagram of a related art BMS wake-up mode;

fig. 2 is a block diagram of a BMS bidirectional wake-up circuit according to an embodiment of the present invention;

fig. 3 is a schematic block diagram of a motherboard wake-up slave circuit of a BMS bidirectional wake-up circuit according to an embodiment of the present invention;

fig. 4 is a schematic block diagram of a slave board wake-up motherboard circuit of the BMS bidirectional wake-up circuit according to an embodiment of the present invention;

fig. 5 is a circuit diagram of a signal transmission circuit of a BMS bidirectional wake-up circuit according to an embodiment of the present invention.

Detailed Description

The following detailed description of the embodiments of the present invention will be made with reference to the accompanying drawings. It is to be understood that the description of the embodiments herein is for purposes of illustration and explanation only and is not intended to limit the invention.

Fig. 2 is a block diagram of a BMS bidirectional wake-up circuit according to an embodiment of the present invention; fig. 3 is a schematic block diagram of a motherboard wake-up slave circuit of a BMS bidirectional wake-up circuit according to an embodiment of the present invention; fig. 4 is a schematic block diagram of a slave board wake-up main board circuit of the BMS bidirectional wake-up circuit according to an embodiment of the present invention.

As shown in fig. 2, an embodiment of the present invention provides a battery management system BMS bidirectional wake-up circuit, which includes a main board BCU and N (N is a positive integer) slave boards CMC, and further includes N signal transmission circuits. The N slave boards (CMC #1 to CMC # N) are connected in series by a daisy chain circuit, and detection signals (fault signals) are transmitted between the slave boards (for example, between CMC #1 and CMC #2, between CMC #2 and CMC #3, between … CMC # N-1 and CMC # N) and between the nth slave board and the master board (between CMC # N and BCU) by the signal transmission circuit.

As shown in fig. 3, the main board BCU includes a microcontroller MCU, a power chip SBC, and an isolation network transceiver MC33664, the power chip SBC supplies power to the microcontroller MCU, and the microcontroller MCU is connected to a daisy chain circuit through the isolation network transceiver MC 33664. The power chip SBC receives a vehicle control unit CAN signal or a KL15 signal to enter a working mode, the MCU is powered on and sends a wake-up command in an SPI communication mode, the SPI signal is converted into a daisy chain signal through the isolation network transceiver MC33664, the daisy chain signal is transmitted between the CMC step by step, the CMC is awakened in sequence, and the function of awakening the slave board by the mainboard is realized.

For convenience of description, a signal transfer circuit between a first slave board and a second slave board (CMC #1 and CMC #2) is defined as a first signal transfer circuit, a signal transfer circuit between the second slave board and a third slave board (CMC #2 and CMC #3) is defined as a second signal transfer circuit, and so on, and a signal transfer circuit between an nth slave board and a master board (CMC # N and BCU) is defined as an nth signal transfer circuit. Fig. 5 is a circuit diagram of a signal transmission circuit of a BMS bidirectional wake-up circuit according to an embodiment of the present invention, and the circuit diagram shown in fig. 5 is a signal transmission circuit diagram between an nth slave board and a master board (between a CMC # N and a BCU), that is, an nth signal transmission circuit. The signal transmission circuit comprises a photoelectric coupler, a current-limiting resistor R1 and a bypass capacitor C1, wherein the input end of the photoelectric coupler is connected with the current-limiting resistor R1, one end of the bypass capacitor C1 is connected with the input end of the photoelectric coupler and the current-limiting resistor R1, and the other end of the bypass capacitor C1 is grounded. The photoelectric coupler plays a role in voltage isolation, avoids high voltage from being introduced into a low-voltage system, and has the principle that a high-level signal is input to enable an internal light-emitting diode to emit light, and a triode is conducted in a photosensitive mode to transmit the high-level signal to a low-voltage end. The bypass capacitor C1 plays a role in filtering out noise waves, and the signal stability is further improved.

Referring to fig. 4 and 5 (the current limiting resistor R1 and the bypass capacitor C1 of the signal transfer circuit are not shown in fig. 4), the current limiting resistor R1 of the nth signal transfer circuit is connected to the signal output terminal (Fault _ out) of the nth slave board CMC # N, and the output terminal of the photocoupler of the nth signal transfer circuit is connected to the power supply chip SBC (Fault _ in) and to the general input/output interface GPIO of the microcontroller MCU. The slave CMC is powered by the battery module, and the active front end AFE rectifying unit is controlled by software program instructions to realize periodic automatic awakening of the slave CMC. For example, the MC33771 battery controller may be set by software to automatically wake up the slave board CMC every 0.1s, 0.2s, 1.0s, 2.0s, 4.0s or 8.0 s. When the slave board detects that the state of the battery core is abnormal, the slave board sends out a fault signal, and the fault signal is transmitted between the slave boards through the photoelectric coupler. After receiving the FAULT signal from the GPIO port of the slave board, the FAULT signal is sent out through the FAULT port, the FAULT signal is transmitted to the next slave board until the FAULT port of the last slave board lights a light emitting diode inside the photoelectric coupler, and a triode inside the photoelectric coupler is conducted. And a triode inside the photoelectric coupler connected with the last slave plate FAULT port is powered by a 12V storage battery, so that a FAULT signal can be transmitted to the MCU and the power chip SBC. The power supply chip SBC is supplied power by the 12V storage battery, and Fault signal transmission to SBC awakens SBC and gets into mode, and SBC provides power to MCU, awakens MCU, realizes the function that the mainboard was awakened to the slave board. The photoelectric coupler and the power chip of the Nth signal transmission circuit are powered by the storage battery, so that the immunity of the circuit can be improved, and false alarm is avoided.

The current limiting resistor R1 of the first signal transmission circuit is connected with a general input/output interface GPIO of the microcontroller MCU, and the output end of a photoelectric coupler of the first signal transmission circuit is connected with the signal input end (Fault _ in) of the first slave board CMC # 1. The first signal transmission circuit is used as a fault signal self-checking circuit, before the BMS is in a sleep state, a GPIO port of the MCU sends a high-level signal to the photoelectric coupler, the high-level signal is input into the first slave plate CMC #1 as a fault signal, the fault signal is sequentially transmitted among the slave plates (CMC #1 to CMC # N), if the MCU can receive the returned fault signal, the signal transmission circuits are normal, and if the MCU cannot receive the returned fault signal, the signal transmission circuits have failed nodes. The fault signal self-checking circuit can ensure the normal execution of the function of awakening the mainboard from the slave board.

The utility model discloses embodiment provides a two-way wake-up circuit's of BMS theory of operation does: when BMS dormancy, mainboard BCU is out of work, and the automatic slave plate CMC that awakens up of initiative front end AFE through software setting periodicity is automatic, carries out battery state information acquisition and judgement from the slave plate CMC, if CMC detects battery state unusual (voltage, electric current, the temperature value of battery electricity core exceed the threshold value of settlement), the fault signal of AFE becomes the high level, and the fault signal passes through optoelectronic coupler and transmits step by step. Finally, simultaneously transmitting the Fault signal to a GPIO port of the power chip SBC and the MCU, and after the MCU is awakened, determining whether the MCU is awakened by the Fault signal by detecting the high and low levels of the GPIO port; if so, the MCU executes a corresponding program to command the slave board CMC to reacquire the battery state information, the reacquired battery state information is transmitted to the MCU through the daisy chain, and the MCU analyzes and processes the battery state information; if the MCU judges that the battery state information is normal and the fault signal is in error report, the MCU returns to the dormant state to wait for the next awakening. In the embodiment, the fault signal of the AFE is used as the wake-up signal of the power chip, so that the working mode of waking up the mainboard from the slave board is realized. The mainboard has Fault signal reception and confirms the function, and the Fault signal also transmits to MCU's GPIO mouth when transmitting to power chip promptly, and MCU is awaken up by the Fault signal through detecting affirmation, awakens up with CAN signal and KL15 signal and awakens up to distinguish.

The parameters of the signal transmission circuit are selected as follows: the photoelectric coupler needs to bear the voltage of the battery module, and the withstand voltage of the photoelectric coupler is 1.2-1.5 times of the voltage of the module. The current limiting resistor R1 is preferably a resistor with a resistance of 330 Ω and a power of 0.1W. The bypass capacitor C1 preferably has a capacitance of 47nF and a withstand voltage of 100V.

The utility model discloses embodiment still provides a battery management system, including the two-way awakening circuit of foretell battery management system.

The utility model discloses the embodiment still provides an electric vehicle, including foretell battery management system.

The present invention has been described in detail with reference to the accompanying drawings, but the embodiments of the present invention are not limited to the details of the above embodiments, and the technical idea of the embodiments of the present invention can be within the scope of the present invention, and can be modified to various simple modifications, and these simple modifications all belong to the protection scope of the embodiments of the present invention. It should be noted that the various features described in the above embodiments may be combined in any suitable manner without departing from the scope of the invention. In order to avoid unnecessary repetition, the embodiments of the present invention do not separately describe various possible combinations.

In addition, various embodiments of the present invention can be combined arbitrarily, and the embodiments of the present invention should be considered as disclosed in the present invention as long as they do not violate the idea of the embodiments of the present invention.

Claims

1. A bidirectional wake-up circuit of a battery management system comprises a main board and N slave boards, and is characterized by also comprising N signal transmission circuits;

the N slave plates are sequentially connected through a daisy chain circuit, and detection signals are transmitted between the slave plates and between the Nth slave plate and the master plate through the signal transmission circuit;

wherein N is a positive integer.

2. The bidirectional wake-up circuit for battery management system according to claim 1, wherein the signal transmission circuit comprises a photo coupler and a current-limiting resistor, and an input terminal of the photo coupler is connected to the current-limiting resistor.

3. The bidirectional wake-up circuit for battery management system according to claim 2, wherein the signal transmission circuit further comprises a bypass capacitor, one end of the bypass capacitor is connected to the input terminal of the photocoupler and the current-limiting resistor, and the other end of the bypass capacitor is grounded.

4. The battery management system bi-directional wake-up circuit of claim 2, wherein the motherboard includes a microcontroller, a power chip and an isolated network transceiver, the power chip supplying power to the microcontroller, the microcontroller being connected to the daisy chain circuit through the isolated network transceiver.

5. The bidirectional wake-up circuit of battery management system according to claim 4, wherein the current-limiting resistor of the signal transmission circuit between the nth slave board and the master board is connected to the signal output terminal of the nth slave board, and the output terminal of the photocoupler of the signal transmission circuit between the nth slave board and the master board is connected to the general input/output interface of the power chip and the microcontroller.

6. The bidirectional wake-up circuit for battery management system according to claim 5, wherein the photocoupler and the power chip of the signal transmission circuit between the Nth slave board and the master board are powered by the storage battery.

7. The bidirectional wake-up circuit of claim 4, wherein a current limiting resistor of the signal transmission circuit between the first slave board and the second slave board is connected to the general input/output interface of the microcontroller, and an output terminal of an opto-coupler of the signal transmission circuit between the first slave board and the second slave board is connected to a signal input terminal of the first slave board.

8. The bi-directional wake-up circuit for battery management system according to claim 1, wherein in the sleep state of the master board, the slave board can wake up automatically and periodically by program instructions.

9. A battery management system comprising the battery management system bidirectional wake-up circuit of any of claims 1-8.

10. An electric vehicle characterized by comprising the battery management system of claim 9.