Battery cell monitoring circuit of battery management system for automobile

Abstract

The utility model discloses a battery cell monitoring circuit of a battery management system for an automobile, which comprises a control center and a microprocessor, the microprocessor is electrically connected with a battery cell, the control center and the microprocessor are electrically connected and interacted, the control center comprises a battery cell state detector, the battery cell state detector is electrically connected with a monitoring timer, and the monitoring timer is electrically connected with the microprocessor. The monitoring timer is electrically connected with the reset and time calibrator, the reset and time calibrator is electrically connected with the reset generator, the reset generator is electrically connected with the first interface and the seventh interface, the first interface is a manual reset interface, and the seventh interface is a reset signal output port. The battery cell state detector is electrically connected with a sixth interface, and the sixth interface is a signal connection unit and is electrically connected with an I / O pin of the microprocessor. The overall performance of the automobile battery management system is improved through the highly integrated design.

Description

Technical Field

[0001] The utility model relates to the field of circuits, and particularly to a core monitoring circuit for an automotive battery management system. Background Art

[0002] In traditional automotive battery management systems, core monitoring usually relies on scattered sensors and relatively independent control modules. Such a layout may lead to problems such as untimely data acquisition, slow system response, low overall efficiency, and poor reliability. Especially in the context of the increasing popularity of electric vehicles, with the increase in the scale of battery packs and the number of cores, how to efficiently and accurately monitor the state of each core has become the key to improving the performance of the battery management system. Previous technologies often lack an efficient reset mechanism and precise signal conditioning means, are easily affected by electromagnetic interference, resulting in the accumulation of measurement errors, and affecting the accuracy of battery management and battery life.

[0003] Therefore, the technical solution of this application is proposed on the basis of solving the problems in the prior art such as insufficient core monitoring accuracy, poor system stability, high maintenance complexity, and low power management efficiency, aiming to improve the overall performance of the automotive battery management system through a highly integrated design. Summary of the Utility Model

[0004] To achieve the above object, the utility model provides the following technical solution:

[0005] A core monitoring circuit for an automotive battery management system includes a control center and a microprocessor. The microprocessor is electrically connected to the core, and the control center and the microprocessor are electrically connected for interaction. The control center includes a core state detector, which is electrically connected to a monitoring timer. The monitoring timer is electrically connected to a reset and time calibrator, and the reset and time calibrator is electrically connected to a reset generator. The reset generator is electrically connected to a first interface and a seventh interface. The first interface is a manual reset interface, and the seventh interface is a reset signal output port.

[0006] Further, the core state detector is electrically connected to a sixth interface. The sixth interface is a signal connection unit, and the sixth interface is electrically connected to the I / O pin of the microprocessor.

[0007] Further, both the reset generator and the monitoring timer are electrically connected to an eighth interface. The eighth interface is a signal output interface. After the eighth interface is electrically connected to a diode D1, it is respectively electrically connected to a diode D2 and the first interface. The diode D2 is electrically connected to a fifth interface, and the fifth interface is a main output interface.

[0008] Further, the VCC pin of the microcontroller is electrically connected to the second interface of the control center. The second interface is a VCC interface, and the second interface is electrically connected to the positive input of an amplifier U1. The output end of the amplifier U1 is electrically connected to the reset generator.

[0009] Further, it further includes a power supply module. The power supply module includes a +5V power supply and a +3.3V power supply. The VCC pin of the microcontroller is electrically connected to the +3.3V voltage to supply power to the microcontroller.

[0010] Further, the control center further includes an amplifier U2. The positive input end of the amplifier U2 is electrically connected to a resistor R1 and a resistor R2 respectively. The resistor R1 is connected to the +5V voltage, and the resistor R2 is grounded. The +5V voltage provided by the power supply module provides the main power supply for the entire circuit. After voltage division by the resistor R1 and R2, a bias voltage is provided for the amplifier U2.

[0011] Further, the output end of the amplifier U2 is electrically connected to the fifth interface, and the fifth interface is electrically connected to the first interface.

[0012] Working principle: In this application, the battery cell state detector is responsible for detecting the state of the battery cell and converting it into an electrical signal. The output signal is transmitted to the microcontroller through the sixth interface so that the microcontroller can obtain real-time battery cell state information. The monitoring timer sets a predefined time period for periodically checking the battery cell state. The output signal of the timer is transmitted to the reset generator and the microcontroller through the eighth interface. The reset and time calibrator generates a reset command according to the signal of the monitoring timer. The reset command is sent to the microcontroller through the seventh interface to cause the microcontroller to re-initialize at a specified time interval to ensure the accuracy of the measurement. The reset generator generates a reset pulse according to the signal of the reset and time calibrator. The pulse is used as a manual reset interface through the first interface, and can also be sent to the microcontroller through the seventh interface. The amplifier U1 receives the power supply from the VCC interface and adjusts it to a voltage suitable for the use of the reset generator. The output of the amplifier U1 is connected to the reset generator to provide a stable power supply for it. The amplifier U2 receives the voltage signals from the resistor R1 and R2 and amplifies them. The amplified signal is sent to the microcontroller through the fifth interface as the main output signal.

[0013] The microcontroller receives the signals from the battery cell state detector and the amplifier U2 and makes corresponding control decisions according to these signals. The VCC pin of the microcontroller is connected to the VCC interface of the control center to ensure stable power supply.

[0014] The signal transmission path of this application:

[0015] The 8th interface connects the reset generator and the monitoring timer to form a signal loop. The 5th interface connects the amplifier U2 and the 1st interface to form the main output signal path.

[0016] This circuit can achieve precise monitoring of the cell state in the automotive battery management system. When the monitoring timer issues a reset instruction, the reset generator generates a reset signal and sends it to the microcontroller through the 7th interface to re-initialize it. At the same time, the cell state detector continuously monitors the cell state and sends the signal to the microcontroller through the 6th interface for its analysis and decision-making.

[0017] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0018] The technical solution proposed in this application realizes efficient and precise monitoring of the cell state by designing a cell monitoring circuit for an automotive battery management system with a compact structure and high functional integration. The specific technical effects are reflected in the following aspects:

[0019] Real-time monitoring and precise control: The cell state detector is directly connected to the microprocessor, which can collect key parameters such as the voltage, current, and temperature of the cell in real time, ensuring the immediacy and accuracy of data collection, helping the microprocessor to make a quick response, timely adjust the battery charging and discharging strategy, extend the battery life, and ensure driving safety.

[0020] Automatic reset and time calibration mechanism: The monitoring timer, in cooperation with the reset and time calibrator and the reset generator, can periodically reset the system to ensure the continuity and consistency of measurement, avoid cumulative errors caused by long-term operation, and improve the working stability of the entire battery management system.

[0021] Signal processing and anti-interference ability: The design of amplifiers U1 and U2 not only optimizes power management and signal conditioning but also enhances the anti-interference ability of the signal, ensuring that the signal received by the microprocessor is pure and of appropriate intensity, improving the reliability and accuracy of data processing.

[0022] Flexible reset mechanism: It provides a manual reset interface (the 1st interface) and an automatic reset signal output (the 7th interface), which not only meets the needs of daily maintenance operations but also ensures that the system can automatically recover in case of anomalies, increasing the usability and fault recovery ability of the system.

[0023] Power management optimization: It adopts a dual power supply module of +5V and +3.3V to supply power to different parts respectively, ensuring the matching of the working voltages of each component. At the same time, the resistors R1 and R2 are used for voltage division to provide a bias voltage for the amplifier U2, realizing an efficient and energy-saving power distribution strategy. Description of the Drawings

[0024] Figure 1Circuit connection block diagram of the present application; Detailed implementation mode

[0025] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0026] The core monitoring circuit of a battery management system for automobiles provided by the present invention, as Figure 1 shown, includes a control center and a microprocessor. The microprocessor is electrically connected to the battery cells. The control center and the microprocessor are electrically connected for interaction. The control center includes a battery cell state detector, which is electrically connected to a monitoring timer. The monitoring timer is electrically connected to a reset and time calibrator. The reset and time calibrator is electrically connected to a reset generator. The reset generator is electrically connected to a first interface and a seventh interface. The first interface is a manual reset interface, and the seventh interface is a reset signal output port. The battery cell state detector is electrically connected to a sixth interface. The sixth interface is a signal connection unit, and the sixth interface is electrically connected to the I / O pin of the microprocessor. The reset generator and the monitoring timer are both electrically connected to an eighth interface. The eighth interface is a signal output interface. After the eighth interface is electrically connected to a diode D1, it is respectively electrically connected to a diode D2 and the first interface. The diode D2 is electrically connected to a fifth interface. The fifth interface is a main output interface. The VCC pin of the microcontroller is electrically connected to the second interface of the control center. The second interface is a VCC interface. The second interface is electrically connected to the positive input of an amplifier U1. The output end of the amplifier U1 is electrically connected to the reset generator. A power supply module is also included. The power supply module includes a +5V power supply and a +3.3V power supply. The VCC pin of the microcontroller is electrically connected to the +3.3V voltage to provide power for the microcontroller. The control center also includes an amplifier U2. The positive input end of the amplifier U2 is respectively electrically connected to a resistor R1 and a resistor R2. The resistor R1 is connected to the +5V voltage, and the resistor R2 is grounded. The +5V voltage provided by the power supply module provides the main power supply for the entire circuit. After being divided by the resistor R1 and the resistor R2, it provides a bias voltage for the amplifier U2. The output end of the amplifier U2 is electrically connected to the fifth interface. The fifth interface is electrically connected to the first interface.

[0027] In order to specifically implement the above technical solutions, a specific embodiment based on the technical solutions of the present application is given below, including the selection of key components in the control center and the configuration of the microprocessor.

[0028] Selection of key components in the control center:

[0029] Microprocessor: Select STM32F103C8T6 as the microprocessor. This MCU has a high-performance ARM Cortex-M3 core and is equipped with rich peripheral resources, such as multiple I / O ports, ADC, timers, etc., which is very suitable for data processing and control tasks in the battery management system.

[0030] Cell status detector: Adopt the MAX1492 cell monitoring IC, which integrates high-precision voltage and temperature detection, can be directly connected to the cell, and reports the cell status to the microprocessor through the I2C interface.

[0031] Monitoring timer: The advanced control timer (TIM1) built into the STM32F103C8T6 microprocessor is set to the auto-reload mode to achieve regular inspection of the cell status at predefined time intervals.

[0032] Reset and time calibrator: Use the dedicated RTC chip DS3231, which not only provides an accurate clock source but also can generate a reset signal as needed and communicates with the microprocessor through the I2C interface.

[0033] Reset generator: Adopt the low-power reset IC LM811, receive the signal from the RTC, generate a reliable reset pulse, and connect to the reset pin of the microprocessor through a hardware circuit.

[0034] Amplifier U1: Select the low-noise operational amplifier OPA365 to adjust the voltage provided by the VCC interface to adapt to the input voltage range required by the reset generator.

[0035] Amplifier U2: Select the high-precision operational amplifier ADA4004-2 for signal amplification to enhance the reference voltage signal obtained from the resistor voltage division and ensure the stability and accuracy of signal transmission.

[0036] Microprocessor configuration example:

[0037] I / O pin configuration: Connect the I2C interface (SDA / SCL) of the MAX1492 to the corresponding I2C port of the STM32 and configure it as the I2C mode in software to receive cell status information.

[0038] Timer configuration: In the firmware of the microprocessor, set TIM1 to the auto-reload mode and configure the preset period (such as once per second or once per minute) to trigger the monitoring timer event.

[0039] Interrupt handling: Configure the interrupts related to the RTC (DS3231) and the reset generator (LM811) so that the microprocessor can quickly respond and execute the corresponding processing logic when receiving the reset signal or the timing event.

[0040] In this application, the battery cell state detector is responsible for detecting the state of the battery cell and converting it into an electrical signal. The output signal is transmitted to the microcontroller through Interface 6, so that the microcontroller can obtain real-time battery cell state information. The monitoring timer is set with a predefined time period for regularly checking the battery cell state. The output signal of the timer is transmitted to the reset generator and the microcontroller through Interface 8. The reset and time calibrator generates a reset command according to the signal of the monitoring timer. The reset command is sent to the microcontroller through Interface 7, causing the microcontroller to re-initialize at a specified time interval to ensure the accuracy of the measurement. The reset generator generates a reset pulse according to the signal of the reset and time calibrator. The pulse is used as a manual reset interface through Interface 1 and can also be sent to the microcontroller through Interface 7. The amplifier U1 receives power from the VCC interface and adjusts it to a voltage suitable for the reset generator. The output of the amplifier U1 is connected to the reset generator to provide it with a stable power supply. The amplifier U2 receives voltage signals from resistors R1 and R2 and amplifies them. The amplified signal is sent to the microcontroller through Interface 5 as the main output signal.

[0041] The microcontroller receives signals from the battery cell state detector and the amplifier U2 and makes corresponding control decisions based on these signals. The VCC pin of the microcontroller is connected to the VCC interface of the control center to ensure stable power supply.

[0042] The signal transmission path of this application:

[0043] Interface 8 is connected to the reset generator and the monitoring timer to form a signal loop. Interface 5 is connected to the amplifier U2 and Interface 1 to form the main output signal path.

[0044] This circuit can achieve precise monitoring of the battery cell state in the automotive battery management system. When the monitoring timer issues a reset instruction, the reset generator generates a reset signal and then sends it to the microcontroller through Interface 7 to re-initialize it; at the same time, the battery cell state detector continuously monitors the battery cell state and sends the signal to the microcontroller through Interface 6 for its analysis and decision-making.

[0045] The technical solution proposed in this application realizes efficient and precise monitoring of the battery cell state by designing a battery cell monitoring circuit for an automotive battery management system with a compact structure and high functional integration. The specific technical effects are reflected in the following aspects:

[0046] Real-time monitoring and precise control: The battery cell state detector is directly connected to the microprocessor, which can collect key parameters such as the voltage, current, and temperature of the battery cell in real time, ensuring the immediacy and accuracy of data collection, helping the microprocessor to make a quick response, timely adjust the battery charge and discharge strategy, extend the battery life and ensure driving safety.

[0047] Automatic reset and time calibration mechanism: The monitoring timer, in cooperation with the reset and time calibrator and the reset generator, can periodically reset the system to ensure the continuity and consistency of measurements, avoid cumulative errors caused by long-term operation, and improve the working stability of the entire battery management system.

[0048] Signal processing and anti-interference ability: The design of amplifiers U1 and U2 not only optimizes power management and signal conditioning but also enhances the signal's anti-interference ability, ensuring that the signals received by the microprocessor are pure and of appropriate strength, and improving the reliability and accuracy of data processing.

[0049] Flexible reset mechanism: It provides a manual reset interface (Interface 1) and an automatic reset signal output (Interface 7), which not only meets the needs of daily maintenance operations but also ensures that the system can automatically recover in case of abnormalities, increasing the system's usability and fault recovery ability.

[0050] Power management optimization: It adopts a dual power supply module of +5V and +3.3V to supply power to different parts respectively, ensuring the matching of the working voltages of each component. At the same time, the voltage divider composed of resistors R1 and R2 provides a bias voltage for amplifier U2, realizing an efficient and energy-saving power distribution strategy.

[0051] Although the embodiments of the present invention have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principle and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A cell monitoring circuit for a battery management system for an automobile, characterized in that: It includes a control center and a microprocessor, the microprocessor is electrically connected to the battery cell, the control center and the microprocessor are electrically connected and interactive, the control center includes a battery cell status detector, the battery cell status detector is electrically connected to a monitoring timer, the monitoring timer is electrically connected to a reset and time calibrator, the reset and time calibrator is electrically connected to a reset generator, the reset generator is electrically connected to a first interface and a seventh interface, the first interface is a manual reset interface, and the seventh interface is a reset signal output port.

2. The cell monitoring circuit of a battery management system for an automobile according to claim 1, characterized in that: The cell state detector is electrically connected to the sixth interface, the sixth interface is a signal connection unit, and the sixth interface is electrically connected to an I / O pin of a microprocessor.

3. The cell monitoring circuit of a battery management system for an automobile according to claim 2, characterized in that: The reset generator and the monitoring timer are both electrically connected to the 8th interface, which is a signal output interface. The 8th interface is electrically connected to a diode D1 and then electrically connected to a diode D2 and the 1st interface respectively. The diode D2 is electrically connected to the 5th interface, and the 5th interface is a main output interface.

4. The cell monitoring circuit of a battery management system for an automobile according to claim 3, characterized in that: The VCC pin of the microprocessor is electrically connected to the second interface of the control center, the second interface is a VCC interface, the second interface is electrically connected to the positive input of an amplifier U1, and the output end of the amplifier U1 is electrically connected to the reset generator.

5. The cell monitoring circuit of a battery management system for an automobile according to claim 4, characterized in that: It also includes a power supply module, which includes a +5V power supply and a +3.3V power supply. The VCC pin of the microprocessor is electrically connected to the +3.3V voltage to provide power for the microprocessor.

6. The cell monitoring circuit of a battery management system for an automobile according to claim 5, characterized in that: The control center also includes an amplifier U2, the positive input terminal of the amplifier U2 is electrically connected to a resistor R1 and a resistor R2, the resistor R1 is connected to a +5V voltage, and the resistor R2 is grounded. The +5V voltage provided by the power module provides the main power supply for the entire circuit, and provides a bias voltage for the amplifier U2 after voltage division by resistors R1 and R2.

7. The cell monitoring circuit of a battery management system for an automobile according to claim 6, characterized in that: The output end of the amplifier U2 is electrically connected to the fifth interface, and the fifth interface is electrically connected to the first interface.

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