WO2025077298A1 - Battery level correction method for battery management system, and system - Google Patents

Abstract

The present application relates to the field of battery management systems of electric vehicles, and in particular to a battery level correction method for a battery management system, and a system. The method comprises: upon receiving a power-off signal, an MCU chip starts a built-in RTC to perform power-off timing, and the MCU chip enters a low-power-consumption mode to operate, wherein during a power-off timing process, the RTC determines whether the duration of the power-off timing is longer than or equal to a time threshold value; if the duration is longer than or equal to the time threshold value, the RTC wakes up the MCU chip to exit the low-power-consumption mode; after the MCU chip exits the low-power-consumption mode, the MCU chip stores a correction flag bit; after the MCU chip stores the correction flag bit, the MCU chip sends a first feedback signal to a power supply chip; when the power supply chip recovers power supply of the MCU chip and the MCU chip enters a working mode again, the MCU chip determines whether the correction flag bit has been stored; and if yes, the MCU chip performs battery level correction. The correction method for a battery management system and the system provided by the present application can realize static OCV correction at relatively low cost and power consumption.

Description

A battery management system power correction method and system

This application claims priority to a Chinese patent application filed with the State Intellectual Property Office on October 11, 2023, with application number 202311312835.6 and application name “A method and system for correcting the power of a battery management system”, the entire contents of which are incorporated by reference in this application.

Technical Field

The present application relates to the field of battery management systems for electric vehicles, and in particular to a method and system for correcting the power level of a battery management system.

Background Art

As the energy crisis and environmental pollution continue to intensify, efficient and low-pollution electric vehicles are gradually becoming a new development trend. And as the endurance of electric vehicles increases and the cost of electronic components decreases, the popularity and penetration of electric vehicles are increasing.

Battery power is an important indicator for evaluating the endurance of electric vehicles. However, there is usually a certain error in the calculation of the battery power of electric vehicles. In order to reduce the error, the battery power can be corrected. In related technologies, the static OCV (Open Circuit Voltage) correction method is usually used. However, the static OCV correction method has problems such as occupying MCU (Microcontroller Unit) resources and high cost and power consumption. Therefore, how to achieve static OCV correction at a lower cost and power consumption has become a problem that needs to be solved.

Summary of the invention

In view of this, the present application provides a battery management system power correction method and system, so as to solve the problems of occupying MCU resources and having high cost and power consumption in the existing static OCV correction technology.

In a first aspect, an embodiment of the present application provides a method for correcting the power of a battery management system, the method being applied to an MCU chip, the MCU chip having a built-in RTC, the method comprising: when the MCU chip receives a power-off signal, starting the built-in RTC to perform power-off timing, and the MCU chip enters a low power consumption mode for operation, wherein, during the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to a time threshold; if the duration is greater than or equal to the time threshold, the RTC wakes up the MCU chip to exit the low power consumption mode; after the MCU chip exits the low power consumption mode, the MCU chip saves a correction flag; after the MCU chip saves the correction flag, the MCU chip sends a first feedback signal to a power chip, the power chip being used to stop supplying power to the MCU chip according to the first feedback signal; when the MCU chip is restored to power by the power chip and enters the working mode again, the MCU chip determines whether the correction flag has been stored; if so, the MCU chip performs power correction; otherwise, the MCU chip does not perform power correction.

In a possible implementation, the MCU chip includes several other modules in addition to the RTC; when the MCU chip receives a power-off signal, the built-in RTC is started to perform power-off timing, and the MCU chip enters a low power consumption mode, including: when the MCU chip receives a power-off signal, other modules built into the MCU chip are turned off, and only the RTC timing function is retained; wherein, the low power consumption mode includes: the RTC in the MCU chip is in a working state, and other modules in the MCU chip are in a non-working state.

In one possible implementation, if the duration is greater than or equal to the time threshold, the RTC wakes up the MCU chip to exit the low power consumption mode, including: if the duration is greater than or equal to the time threshold, the RTC sends a second feedback signal to the MCU chip; after the MCU chip receives the second feedback signal, it starts other modules built into the MCU chip and enters the working mode.

In a possible implementation, during the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to a time threshold, and also includes: when the duration of the power-off timing is less than the time threshold and the MCU chip is running in a low power consumption mode, if the MCU chip switches from the low power consumption mode to the working mode, the MCU sends a third feedback signal to the RTC; when the RTC receives the third feedback signal, the RTC exits this timing, and the MCU chip does not record the correction flag bit this time.

In one possible implementation, the MCU chip is restored to power by the power chip and enters the working mode again, including: when the power chip receives a power-on signal sent by a local control device of the vehicle or receives a wake-up signal sent by a remote mobile device, the power chip restores power to the MCU chip, and the MCU chip enters the working mode again.

In one possible implementation, when the power chip receives a power-on signal sent by a local control device of the vehicle, the power chip resumes power supply to the MCU chip, including: after the local control device of the vehicle controls the vehicle battery to power on, it sends a power-on signal to the power chip; in response to the power-on signal, the power chip supplies power to the MCU chip, so that the MCU chip re-enters the working mode.

In one possible implementation, when the power chip receives a wake-up signal sent by a remote mobile device, the power chip resumes power supply to the MCU chip, including: after the vehicle CAN network receives the wake-up signal sent by the remote mobile device, the vehicle CAN network sends a wake-up signal to the power chip through the CAN chip; in response to the wake-up signal, the power chip supplies power to the MCU chip, so that the MCU chip re-enters the working mode.

In one possible implementation, power correction includes: the MCU chip determines the relationship curve between OCV and SOC; the MCU determines the vehicle battery power according to the current voltage and temperature parameters of the vehicle battery and the relationship curve between OCV and SOC; and corrects the vehicle battery power according to the length of time the MCU chip is restored to power by the power chip and a preset correction coefficient.

In the second aspect, an embodiment of the present application provides a battery management system, including: an MCU chip, a power chip and a CAN chip; the MCU chip and the power chip are electrically connected, and the CAN chip and the power chip are electrically connected; the MCU chip has a built-in RTC, and the MCU chip is used to execute any one of the methods described in the first aspect.

In the solution provided in the embodiment of the present application, the RTC built into the MCU chip is used for power-off timing, and the independent RTC chip, the independent power chip, and the circuit for driving the independent RTC chip and the independent power chip can be omitted in the physical structure; moreover, after the MCU chip saves the correction flag, the MCU chip sends a first feedback signal to the power chip, and the power chip stops supplying power to the MCU chip according to the first feedback signal, thereby reducing power consumption and reducing the operating time of the MCU chip. Therefore, the power correction method of the battery management system can be more efficient. Static OCV correction is achieved with low cost and power consumption.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

FIG1 is a schematic diagram of the structure of a battery management system provided in an embodiment of the present application;

FIG2 is a flow chart of a method for correcting electric quantity of a battery management system provided in an embodiment of the present application;

FIG3 is a flow chart of receiving a power-on signal sent by a local control device of a vehicle provided in an embodiment of the present application;

FIG. 4 is a flow chart of receiving a wake-up signal sent by a remote mobile device provided in an embodiment of the present application.

DETAILED DESCRIPTION

In order to better understand the technical solution of the present application, the embodiments of the present application are described in detail below with reference to the accompanying drawings.

It should be clear that the described embodiments are only part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without creative work are within the scope of protection of the present application.

The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms "a", "said" and "the" used in the embodiments of the present application and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings.

It should be understood that the term "and/or" used in this article is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, A and/or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character "/" in this article generally indicates that the associated objects before and after are in an "or" relationship.

In the prior art, the power correction method of the battery management system includes: when the MCU chip receives a power-off signal, the independent RTC chip records the power-off time, and the MCU chip sends a feedback signal to the power chip, and the power chip stops supplying power to the MCU chip according to the feedback signal. When the MCU chip is powered on again by the power chip and enters the working mode again, the independent RTC chip calculates the difference between the current time and the power-off time, and determines whether the difference meets the set power correction time threshold. If it does, the MCU chip performs power correction; if it does not, the MCU chip does not perform power correction. The above-mentioned power correction method of the battery management system, in order to ensure that the independent RTC chip is always in a working state, requires an independent power chip and a circuit for driving the independent RTC chip and the independent power chip, which not only occupies MCU chip resources but also makes the power consumption and cost of the battery management system higher.

In view of the above problems, an embodiment of the present application provides a method for correcting the power of a battery management system, the method is applied to an MCU chip, the MCU chip has a built-in RTC, the method comprises: when the MCU chip receives a power-off signal, starting the built-in RTC to perform power-off timing, and the MCU chip enters a low power consumption mode, wherein, during the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to a time threshold; if the duration is greater than or equal to the time threshold, the RTC wakes up the MCU chip to exit the low power consumption mode; after the MCU chip exits the low power consumption mode, the MCU chip saves a correction flag bit; after the MCU chip saves the correction flag bit, the MCU chip sends a first feedback signal to the power chip, and the power chip is used to stop supplying power to the MCU chip according to the first feedback signal; when the MCU chip is powered on again by the power chip and enters the working mode again, the MCU chip determines whether the correction flag bit has been stored; if so, the MCU chip performs power correction; otherwise, the MCU chip does not perform power correction.

The details are described below.

As shown in Figure 1, it is a schematic diagram of the structure of a battery management system provided in an embodiment of the present application. As shown in Figure 1, the battery management system 100 may include: a 12V power supply 101, a power chip 102, a CAN chip 103, a crystal oscillator 104, and an MCU chip 105. The MCU chip 105 is electrically connected to the power chip 102 and the crystal oscillator 104 respectively, the CAN chip 103 is electrically connected to the 12V power supply 101 and the power chip 102 respectively, and in addition, the 12V power supply 101 is also electrically connected to the power chip 102.

Among them, the 12V power supply 101 is used to power the battery management system 100; the power chip 102 is used to power on and off the MCU chip 105 according to different signals; the CAN chip 103 is used to receive the wake-up signal sent by the remote mobile device through the vehicle CAN network, and to send the wake-up signal to the power chip 102; the crystal oscillator 104 is used to provide the clock source required by the battery management system 100; the MCU chip 105 is used to execute some or all of the steps in each embodiment of the method for correcting the power of the battery management system 100 provided by the present invention. Among them, the MCU chip 105 has a built-in RTC, and the RTC is used for the MCU chip 105 to perform power-off timing when receiving the power-off signal, and to judge in real time whether the duration of the power-off timing is greater than or equal to the time threshold.

In addition, the CAN chip 103 is connected to the vehicle CAN network outside the battery management system, and the vehicle CAN network is used to receive a wake-up signal sent by a remote mobile device and to send the wake-up signal to the CAN chip 103 .

In the battery management system 100 shown in FIG. 1 , when the MCU chip 105 receives a power-off signal, it can execute the power correction method of the embodiment of the present invention, and decide whether to correct the power of the battery based on the power correction method of the embodiment of the present invention.

As shown in FIG2 , it is a flow chart of a method for correcting the power of a battery management system provided in an embodiment of the present application. As shown in FIG2 , the processing steps of the method include:

Step S201: When the MCU chip 105 receives a power-off signal, the built-in RTC is started to perform power-off timing, and the MCU chip 105 enters a low power consumption mode. The MCU chip 105 includes several other modules in addition to the RTC.

When the MCU chip 105 receives the power-off signal, other modules built into the MCU chip 205 are turned off, and only the RTC timing function is retained. The low power consumption mode includes: the RTC in the MCU chip 105 is in a working state, and other modules in the MCU chip 105 are in a non-working state.

Step S202: During the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to the time threshold. If the duration is greater than or equal to the time threshold, step S203 is executed; otherwise, step S202 is continued.

Step S203: When the time is greater than or equal to the time threshold, the RTC wakes up the MCU chip 105 to exit the low power consumption mode.

One possible implementation is that if the power-off timing duration is greater than or equal to the time threshold, the RTC sends a second feedback signal to the MCU chip 105; after receiving the second feedback signal, the MCU chip 105 starts other modules built into the MCU chip 105 and enters the working mode. The MCU entering the working mode includes: the RTC and other modules built into the MCU chip 105 are in the working state.

Step S204: After the MCU chip 105 exits the low power consumption mode, the MCU chip 105 saves the correction flag, wherein the correction flag is used to indicate that the vehicle battery needs to be corrected for power.

Step S205: After the MCU chip 105 saves the correction flag, the MCU chip 105 sends a first feedback signal to the power chip 102, and the power chip 102 is used to stop supplying power to the MCU chip 105 according to the first feedback signal.

The first feedback signal is used to notify the power chip 102 to stop supplying power to the MCU chip 105. One possible implementation is that after receiving the first feedback signal, the power chip 102 disconnects from the MCU chip 105, so that the MCU chip 105 enters a non-working mode. The MCU chip 105 enters a non-working mode including: the RTC and other modules built into the MCU chip 105 are all in a non-working state.

Step S206: When the MCU chip 105 is powered on again by the power chip 102 and enters the working mode again, the MCU chip 105 determines whether a correction flag has been stored.

Among them, the MCU chip 105 is restored to power by the power chip 102 and enters the working mode again, including: when the power chip 102 receives a power-on signal sent by the local control device of the vehicle or receives a wake-up signal sent by a remote mobile device, the power chip 102 restores power to the MCU chip 105, and the MCU chip 105 enters the working mode again, as shown in Figures 3 and 4.

Step S207: When the correction flag has been stored in the MCU chip 105, the MCU chip 105 performs power correction.

Among them, the power correction includes: the MCU chip 105 determines the relationship curve between OCV and SOC; the MCU chip 105 determines the vehicle battery power according to the current voltage and temperature parameters of the vehicle battery and the relationship curve between OCV and SOC; the vehicle battery power is corrected according to the length of time the MCU chip 105 is restored to power by the power chip 102 and a preset correction coefficient.

Step S208: When there is no correction flag in the MCU chip 105, the MCU chip 105 does not perform power correction.

In the above step S202, when the duration of the power-off timing is less than the time threshold and the MCU chip 105 is running in the low power mode, if the MCU chip 105 switches from the low power mode to the working mode, the MCU chip 105 sends a third feedback signal to the RTC; when the RTC receives the third feedback signal, the RTC exits this timing, and the MCU chip 105 does not record this correction flag. The third feedback signal is used to notify the RTC to exit this timing.

In the method of the embodiment of the present invention, the MCU chip 105 has a built-in RTC. When the MCU chip 105 receives a power-off signal, the built-in RTC is started to perform power-off timing, and the MCU chip 105 enters a low-power mode. The MCU chip 105 determines whether to exit the low-power mode according to whether the timing duration of the RTC is greater than or equal to the time threshold; when the duration is greater than or equal to the time threshold, the MCU chip 105 exits the low-power mode, saves the correction flag, and then the MCU chip 105 sends a first feedback signal to the power chip 102, and the power chip 102 stops supplying power to the MCU chip 105 according to the received first feedback signal; when the MCU chip 105 is restored by the power chip 102 and enters the working mode again, the MCU chip 105 determines whether to perform power correction according to whether a correction flag has been stored. The above method uses the built-in RTC of the MCU chip 105 to perform power-off timing, without the need for an independent RTC chip, an independent power chip, and a circuit for driving the independent RTC chip and the independent power chip, which can reduce costs. Moreover, after the MCU chip 105 saves the correction flag, the power chip 102 stops supplying power to the MCU chip 105 , and the MCU chip 105 enters a non-working state, which reduces power consumption while reducing the operating time of the MCU chip 105 , helping to ensure the life of the MCU chip 105 .

As shown in FIG3 , a flowchart of receiving a power-on signal sent by a local control device of a vehicle is provided in an embodiment of the present application. As shown in FIG3 , the processing steps of the method include:

Step S301: The local control device of the vehicle initiates a power-on signal and sends the power-on signal to the power chip 102. The local control device of the vehicle may be a switch, a key, etc. of the vehicle system. The power-on signal is a model for controlling the power-on of the vehicle battery. As a possible implementation, the power-on signal initiated by the local control device of the vehicle may be a signal of the key of the vehicle system to open the car door.

Step S302 : After receiving the power-on signal, the power chip 102 supplies power to the MCU chip 105 in response to the power-on signal.

Step S303: After receiving the power from the power chip 102, the MCU chip 105 enters the working mode again.

Step S304: After the MCU chip 105 enters the working mode again, it is determined whether a correction flag has been stored. If the correction flag has been stored in the MCU chip 105, step S305 is executed; otherwise, step S306 is executed.

Step S305: When the correction flag has been stored in the MCU chip 105, the MCU chip 105 performs power correction.

One possible implementation method is that when a correction flag has been stored in the MCU chip 105, the MCU chip 105 determines the relationship curve between OCV and SOC; the MCU chip 105 determines the vehicle battery power according to the current voltage and temperature parameters of the vehicle battery and the relationship curve between OCV and SOC; the vehicle battery power is corrected according to the length of time the MCU chip 105 is restored to power by the power chip 102 and a preset correction coefficient.

Step S306: When there is no correction flag in the MCU chip 105, the MCU chip 105 does not perform power correction.

As shown in FIG4 , a flowchart of receiving a wake-up signal sent by a remote mobile device is provided in an embodiment of the present application. As shown in FIG4 , the processing steps of the method include:

Step S401: The remote mobile device initiates a wake-up signal and sends the wake-up signal to the vehicle CAN network. The remote mobile device may be a tablet computer, a mobile phone, or other device that has a wake-up signal initiation function. As a possible implementation method, the wake-up signal may be a command for the mobile phone to control the vehicle to turn on the air conditioner.

Step S402 : After the vehicle CAN network receives the wake-up signal sent by the remote mobile device, the vehicle CAN network sends the wake-up signal to the CAN chip 103 .

Step S403 : after receiving the wake-up signal, the CAN chip 103 sends the wake-up signal to the power chip 102 .

Step S404: After receiving the wake-up signal, the power chip 102 supplies power to the MCU chip 105 in response to the wake-up signal.

Step S405: After receiving the power from the power chip 102, the MCU chip 105 enters the working mode again.

Step S406: After the MCU chip 105 enters the working mode again, it is determined whether a correction flag has been stored. If the correction flag has been stored in the MCU chip 105, step S407 is executed; otherwise, step S408 is executed.

Step S407: When the correction flag is already stored in the MCU chip 105, the MCU chip 105 performs power correction. One possible implementation is that when the correction flag is already stored in the MCU chip 105, the MCU chip 105 determines the relationship curve between OCV and SOC; the MCU chip 105 determines the vehicle battery power according to the current voltage and temperature parameters of the vehicle battery and the relationship curve between OCV and SOC; the vehicle battery power is corrected according to the length of time the MCU chip 105 is restored to power by the power chip 102 and the preset correction coefficient.

Step S408: When there is no correction flag in the MCU chip 105, the MCU chip 105 does not perform power correction.

The above description is only a preferred embodiment of the embodiment of the present invention and is not intended to limit the embodiment of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiment of the present invention should be included in the scope of protection of the embodiment of the present invention.

Claims (9)

A method for correcting the electric quantity of a battery management system, characterized in that the method is applied to an MCU chip, the MCU chip has an RTC built in, and the method comprises: When the MCU chip receives a power-off signal, the built-in RTC is started to perform power-off timing, and the MCU chip enters a low power consumption mode, wherein during the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to a time threshold; If the duration is greater than or equal to the time threshold, the RTC wakes up the MCU chip to exit the low power consumption mode; After the MCU chip exits the low power consumption mode, the MCU chip saves the correction flag bit; After the MCU chip saves the correction flag, the MCU chip sends a first feedback signal to the power chip, and the power chip is used to stop supplying power to the MCU chip according to the first feedback signal; When the MCU chip is powered on again by the power chip and enters the working mode again, the MCU chip determines whether the correction flag bit has been stored; If yes, the MCU chip performs power correction; Otherwise, the MCU chip does not perform power correction. The method according to claim 1 is characterized in that the MCU chip includes several other modules in addition to the RTC; when the MCU chip receives a power-off signal, the built-in RTC is started to perform power-off timing, and the MCU chip enters a low power consumption mode, including: When the MCU chip receives a power-off signal, other modules built into the MCU chip are turned off, and only the RTC timing function is retained; The low power consumption mode includes: the RTC in the MCU chip is in a working state, and other modules in the MCU chip are in a non-working state. The method according to claim 2 is characterized in that if the duration is greater than or equal to the time threshold, the RTC wakes up the MCU chip to exit the low power consumption mode, comprising: If the duration is greater than or equal to the time threshold, the RTC sends a second feedback signal to the MCU chip; After receiving the second feedback signal, the MCU chip starts other modules built into the MCU chip and enters a working mode. The method according to claim 1, characterized in that, during the power-off timing process, the RTC determines whether the duration of the power-off timing is greater than or equal to a time threshold, further comprising: When the duration of the power-off timing is less than the time threshold and the MCU chip is running in the low power consumption mode, if the MCU chip switches from the low power consumption mode to the working mode, the MCU chip sends a third feedback signal to the RTC; When the RTC receives the third feedback signal, the RTC exits the current timing, and the MCU chip does not record the correction flag bit of this time. The method according to claim 1 is characterized in that the MCU chip is powered back on by the power chip and enters the working mode again, comprising: When the power chip receives a power-on signal sent by a local control device of the vehicle or a wake-up signal sent by a remote mobile device, the power chip resumes power supply to the MCU chip, and the MCU chip resumes power supply to the MCU chip. Enter working mode. The method according to claim 5 is characterized in that when the power chip receives a power-on signal sent by a local control device of the vehicle, the power chip resumes power supply to the MCU chip, comprising: After the vehicle battery is powered on, the local control device of the vehicle sends a power-on signal to the power chip; In response to the power-on signal, the power chip supplies power to the MCU chip, so that the MCU chip re-enters the working mode. The method according to claim 5 is characterized in that when the power chip receives a wake-up signal sent by a remote mobile device, the power chip resumes power supply to the MCU chip, comprising: After the vehicle CAN network receives the wake-up signal sent by the remote mobile device, the vehicle CAN network sends the wake-up signal to the power chip through the CAN chip; In response to the wake-up signal, the power chip supplies power to the MCU chip, so that the MCU chip re-enters the working mode. The method according to claim 1, characterized in that the power correction comprises: The MCU chip determines the relationship curve between OCV and SOC; The MCU chip determines the battery capacity of the vehicle according to the current voltage and temperature parameters of the vehicle battery and the relationship curve between OCV and SOC; The vehicle battery power is corrected according to the duration for which the MCU chip is restored to power by the power chip and a preset correction coefficient. A battery management system, characterized in that it comprises: an MCU chip, a power chip and a CAN chip; the MCU chip and the power chip are electrically connected, and the CAN chip and the power chip are electrically connected; The MCU chip has a built-in RTC, and the MCU chip is used to execute the method described in any one of claims 1 to 8.