A battery pack monitoring method and system based on Bluetooth low energy technology

Abstract

The present application discloses a battery pack monitoring method and system based on Bluetooth low-power technology, which relates to the field of wireless communication network technology, wherein the method includes: collecting initial state data of the battery pack; broadcasting the initial state data using Bluetooth low-power technology; receiving the initial state data, determining the state change model of the battery pack based on the initial state data, and determining the time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model; collecting and broadcasting the real-time state data of the battery pack according to the time point; and evaluating the state of the battery pack based on the real-time state data. The present application uses Bluetooth low-power technology to realize the wireless transmission of battery pack state data, eliminating the trouble of wired transmission, and predicts various state data in the process of collecting state data, and only collects and transmits state data when the state data changes significantly, effectively reducing the load on the battery pack caused by wireless communication.

Description

Technical Field

[0001] The present application relates to the field of wireless communication network technology, and in particular to a battery pack monitoring method and system based on Bluetooth low energy technology. Background Art

[0002] In energy storage and new energy vehicles, the battery pack is the basic unit for storing energy. Each battery pack consists of a power management unit and multiple batteries. The multiple batteries are connected in sequence to the power management unit. The charging and discharging of the batteries are controlled by the power management unit. The power management unit can be used to obtain data such as the working status and health of the battery pack.

[0003] In order to determine whether the working status of the battery pack is normal, it is necessary to export various data of the power management unit, analyze these data in the background, and issue an alarm according to the actual situation after obtaining the conclusion of whether the status of the battery pack is normal. At present, the way to obtain data from the power management unit is to directly connect the data cable to the power management unit. Although this wired connection method is stable and reliable, it leads to complex wiring and increases the difficulty of maintenance. Moreover, the wired connection method needs to analyze the data of a battery pack each time the data of the battery pack is obtained before the data of the next battery pack can be collected and analyzed, and the data processing efficiency is low. Summary of the invention

[0004] The embodiments of the present application provide a battery pack monitoring method and system based on Bluetooth low energy technology, which is used to solve the problems of complex wiring and low data processing efficiency in the wired connection method in the prior art.

[0005] On the one hand, an embodiment of the present application provides a battery pack monitoring method based on Bluetooth low energy technology, including:

[0006] Collect the initial status data of the battery pack;

[0007] Use Bluetooth Low Energy (BLE) technology to broadcast initial status data;

[0008] Receive initial state data, determine a state change model of the battery pack according to the initial state data, and determine a time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model;

[0009] Collect and broadcast real-time status data of battery packs according to time points;

[0010] Evaluate the status of the battery pack based on real-time status data.

[0011] On the other hand, the embodiment of the present application also provides a battery pack monitoring system based on Bluetooth low energy technology, including:

[0012] A data acquisition module, used to collect the initial state data of the battery pack;

[0013] A data broadcast module, used to broadcast initial status data using Bluetooth low energy technology;

[0014] A receiving and evaluating terminal, used to receive initial state data, determine a state change model of the battery pack according to the initial state data, and determine a time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model;

[0015] The data acquisition module collects the real-time status data of the battery pack according to the time point, the data broadcasting module uses Bluetooth low energy technology to broadcast the real-time status data, and the receiving and evaluation terminal evaluates the status of the battery pack according to the real-time status data.

[0016] A battery pack monitoring method and system based on Bluetooth low energy technology in this application has the following advantages:

[0017] The use of Bluetooth low-power technology realizes the wireless transmission of battery pack status data, eliminating the trouble of wired transmission. In the process of collecting status data, various status data are predicted, and status data is only collected and transmitted when there is a significant change in the status data, effectively reducing the load on the battery pack caused by wireless communication. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art 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 work.

[0019] Figure 1 A flowchart of a battery pack monitoring method based on Bluetooth low energy technology provided in an embodiment of the present application. DETAILED DESCRIPTION

[0020] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0021] Figure 1A flowchart of a battery pack monitoring method based on Bluetooth low energy technology provided in an embodiment of the present application. An embodiment of the present application provides a battery pack monitoring method based on Bluetooth low energy technology, the method comprising the following steps:

[0022] S100, collecting initial status data of the battery pack.

[0023] Exemplarily, each battery pack is connected to a power management unit, which is responsible for controlling the charging and discharging of each battery in the battery pack. Therefore, the power management unit can be used to collect initial state data of the battery pack.

[0024] The initial state data referred to in the embodiment of the present application is the state data collected for the first time by the power management unit after the monitoring system is established. The initial state data includes the initial voltage, initial current, initial temperature and charge and discharge state of the battery pack, wherein the charge and discharge state is one of two specific states: charging state and discharging state.

[0025] S110, uses Bluetooth low energy technology to broadcast initial status data.

[0026] For example, Bluetooth low energy is a wireless communication technology with low power consumption and high transmission speed developed based on Bluetooth technology. Bluetooth low energy technology can realize wireless transmission of battery pack status data, which solves the problems of complex wiring and low data processing efficiency caused by wired transmission in the prior art. Moreover, Bluetooth low energy technology has a very small power consumption load on the battery pack. As long as the frequency of data transmission and reception is properly controlled, the power consumption can be controlled within a certain range, thereby reducing the power consumption load of the battery pack.

[0027] In an embodiment of the present application, a chip compliant with the Bluetooth low energy 5.0 standard is used to broadcast the initial state data.

[0028] Furthermore, after the initial state data and the real-time state data are collected, the initial state data and the real-time state data are respectively formed into multiple data pages, which are broadcast in the order of the data pages. Since Bluetooth low energy technology limits the data length to a maximum of 31 bytes, and the initial state data usually exceeds this length, after the initial state data is collected, the application writes the initial state data into each data page with a length of 31 bytes in sequence, and starts writing the next data page after one data page is full, until the initial state data is written. After obtaining multiple data pages, each data page will be broadcast in order.

[0029] S120, receiving initial state data, determining a state change model of the battery pack according to the initial state data, and determining a time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model.

[0030] Exemplarily, after receiving the initial state data, a matching charging state change model or a discharging state change model is selected according to the charging and discharging state and the initial temperature in the initial state data, and the time point when the voltage or current change of the battery pack exceeds a set threshold is determined according to the charging state change model or the discharging state change model.

[0031] Specifically, when the battery pack is in a charging state, a model matching the initial temperature can be selected from multiple charging state change models. Correspondingly, when the battery pack is in a discharging state, a model matching the initial temperature can be selected from multiple discharging state change models. Both the charging state change model and the discharging state change model are pre-stored in the storage unit, and only need to be selected according to the initial temperature when used.

[0032] The charging state change model is the change of voltage and current of the battery pack over time under the charging state. The model is represented by a mathematical function, preferably a polynomial. In the charging state, the battery pack can be charged by a constant current charging, constant current constant voltage charging, constant power charging and constant power constant voltage charging. No matter which charging method is used, it will remain unchanged once the charging method is determined. In different charging methods, the change of current and voltage is different. For example, in the constant current charging method, the charging current remains basically unchanged, while the charging voltage will gradually increase over time. In constant power charging and constant power constant voltage charging, the current gradually decreases over time, while the voltage gradually increases over time. Therefore, under different charging methods, the current and voltage will change differently. For the selected charging method, the monitoring object of the state change can be determined, that is, only monitoring the voltage or monitoring the voltage and current at the same time. Based on the determined state change monitoring object, after selecting the charging state change model that matches the initial temperature, the change of each state change monitoring object over time can be calculated. When, after a period of time, the change in the state change monitoring object relative to the initial voltage or initial current reaches the voltage setting threshold or the current setting threshold, it means that the state of the battery pack has changed significantly, and the real-time state data of the battery pack needs to be re-collected. The time when the change in the state change monitoring object reaches the voltage setting threshold or the current setting threshold is used as the time point for collecting the real-time state data.

[0033] The discharge state change model is similar to the charge state change model, so the discharge state change model is not described in detail.

[0034] Further, each charging state change model or each discharging state change model corresponds to a temperature range respectively. When the initial temperature is within a temperature range, the time point is determined using the charging state change model or the discharging state change model corresponding to the temperature range.

[0035] Specifically, the charging state change model or the discharging state change model is a mathematical model obtained after charging or discharging the battery pack under different temperature environments in an experimental environment. The initial temperature is a specific temperature value, which has many possibilities, but the number of charging state change models or discharging state change models cannot be very large, so the idea of ​​fuzzy control is adopted to regard multiple initial temperatures within a temperature range as the same initial temperature. The temperature range corresponds to a charging state change model or a discharging state change model. Selecting the charging state change model or the discharging state change model can predict the voltage or current change state of the battery pack.

[0036] Furthermore, after selecting a charging state change model or a discharging state change model according to the initial temperature and determining the time point according to the selected charging state change model or the discharging state change model, each time the real-time status data is obtained, a matching charging state change model or the discharging state change model is reselected according to the real-time temperature and the charging and discharging status in the real-time status data, and then the time point is updated.

[0037] Specifically, the real-time status data includes real-time voltage, real-time current, real-time temperature and charge and discharge status. Similar to the initial status data, the charge and discharge status in the real-time status data is also one of the charge state or discharge state, and when a real-time temperature is within a certain temperature range, the charge state change model or discharge state change model corresponding to the temperature range will be selected as the state change model corresponding to the real-time temperature. As charging or discharging proceeds, the temperature of the battery pack may change. Once the temperature changes, the applicable charge state change model or discharge state change model may also change. Therefore, each time the real-time status data is received, it will be determined whether to select the charge state change model or the discharge state change model according to the charge and discharge status, and then the corresponding state change model will be selected from multiple charge state change models or discharge state change models according to the real-time temperature. After selecting the charge state change model or discharge state change model, the time point when the voltage or current change of the battery pack exceeds the set threshold will be recalculated, and the purpose of updating the time point is finally achieved.

[0038] S130, collecting and broadcasting real-time status data of the battery pack according to time points.

[0039] Exemplarily, the above-mentioned time point is the interval time after the power management unit collects initial status data or real-time status data and then collects real-time status data again. After receiving the data at the time point, the power management unit will start timing and determine whether the current time has reached the time point. If it has reached it, it will start collecting and broadcasting real-time status data.

[0040] In an embodiment of the present application, the real-time temperature is collected at a fixed frequency, and the real-time voltage and real-time current are collected at a time point. Since the temperature is affected by many factors, it is difficult to predict the temperature. Therefore, the present application will collect the real-time temperature at a fixed frequency, and the real-time voltage and real-time current can be predicted by the charging state change model or the discharge state change model, so these two data will be collected at the predicted time point. Compared with the complete real-time status data, the amount of real-time temperature data is very small, so even if a fixed frequency is used for collection and broadcasting, the load on the battery pack is very small and can be almost ignored.

[0041] Furthermore, since the time points predicted by the charging state change model or the discharging state change model are irregular, there may be a situation where the predicted time point is very close to the time point of a certain real-time temperature collection. At this time, if the difference between the time point when the power management unit receives the real-time voltage and real-time current collection and the time point when the real-time temperature is collected next time is less than a certain time value, the real-time temperature can be collected together with the real-time voltage, real-time current and charging and discharging state collection, and broadcasted together. After the time point for the next real-time temperature collection arrives, the real-time temperature will no longer be collected, but the next real-time temperature collection will still be carried out at a fixed frequency and will not be affected by the collection of real-time voltage and real-time current.

[0042] S140, evaluating the status of the battery pack according to the real-time status data.

[0043] Exemplarily, when evaluating the status of the battery pack based on real-time status data, the health of the battery pack is evaluated based on the real-time voltage and real-time current, and the real-time temperature is compared with the temperature threshold to evaluate the temperature status of the battery pack.

[0044] Specifically, after obtaining the real-time voltage and real-time current in the real-time status data, the internal resistance method or the volt-ampere method can be used to calculate the health of the battery pack. While calculating the health of the battery pack, the real-time temperature can also be compared with the temperature threshold indicating a dangerous situation to determine whether the temperature of the battery pack is normal.

[0045] Furthermore, when it is determined that the battery pack is in an abnormal state, a safety warning is issued.

[0046] The present application also provides a battery pack monitoring system based on Bluetooth low energy technology, the system comprising:

[0047] A data acquisition module, used to collect the initial state data of the battery pack;

[0048] A data broadcast module, used to broadcast initial status data using Bluetooth low energy technology;

[0049] A receiving and evaluating terminal, used to receive initial state data, determine a state change model of the battery pack according to the initial state data, and determine a time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model;

[0050] The data acquisition module collects the real-time status data of the battery pack according to the time point, the data broadcasting module uses Bluetooth low energy technology to broadcast the real-time status data, and the receiving and evaluation terminal evaluates the status of the battery pack according to the real-time status data.

[0051] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0052] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A battery pack monitoring method based on Bluetooth low energy technology, characterized in that: include: Collect the initial status data of the battery pack; The initial state data includes the initial voltage, initial current, initial temperature and charge and discharge state of the battery pack; Broadcasting the initial state data using Bluetooth low energy technology; Receive the initial state data, determine a charging state change model or a discharging state change model that matches the battery pack according to the initial temperature and the charging and discharging state in the initial state data, and determine a time point when a voltage or current change in real-time state data collected by the battery pack in subsequent monitoring exceeds a set threshold based on the charging state change model or the discharging state change model; the charging state change model and the discharging state change model are both pre-stored in a storage unit, each of the charging state change models or each of the discharging state change models corresponds to a temperature range, and when the initial temperature is within one of the temperature ranges, the charging state change model or the discharging state change model corresponding to the temperature range is used to determine the time point; Collecting and broadcasting the real-time status data of the battery pack according to the time point; The real-time status data includes real-time voltage, real-time current, real-time temperature and charging and discharging status; The status of the battery pack is evaluated according to the real-time status data.

2. The battery pack monitoring method based on Bluetooth low energy technology according to claim 1, characterized in that: The real-time temperature is collected at a fixed frequency, and the real-time voltage and the real-time current are collected at the time points.

3. The battery pack monitoring method based on Bluetooth low energy technology according to claim 1, characterized in that: After selecting the charging state change model or the discharging state change model according to the initial temperature and determining the time point according to the selected charging state change model or the discharging state change model, each time the real-time status data is obtained, the matching charging state change model or the discharging state change model is reselected according to the real-time temperature and the charging and discharging status in the real-time status data, and then the time point is updated.

4. The battery pack monitoring method based on Bluetooth low energy technology according to claim 1, characterized in that: When evaluating the status of the battery pack according to the real-time status data, the health of the battery pack is evaluated according to the real-time voltage and real-time current, and the real-time temperature is compared with the temperature threshold to evaluate the temperature status of the battery pack.

5. The battery pack monitoring method based on Bluetooth low energy technology according to claim 4 is characterized in that: When the battery pack is determined to be in an abnormal state, a safety alarm is issued.

6. The battery pack monitoring method based on Bluetooth low energy technology according to claim 1, characterized in that: After the initial state data and the real-time state data are acquired, the initial state data and the real-time state data are respectively formed into a plurality of data pages, which are broadcasted in the order of the data pages.

7. A system for applying a battery pack monitoring method based on Bluetooth low energy technology as described in any one of claims 1 to 6, characterized in that: include: A data acquisition module, used to collect the initial state data of the battery pack; A data broadcast module, used for broadcasting the initial state data using Bluetooth low energy technology; A receiving and evaluating terminal, configured to receive the initial state data, determine a state change model of the battery pack according to the initial state data, and determine a time point for collecting real-time state data of the battery pack in subsequent monitoring based on the state change model; the initial state data includes an initial voltage, an initial current, an initial temperature, and a charge and discharge state of the battery pack, and the real-time state data includes a real-time voltage, a real-time current, a real-time temperature, and a charge and discharge state; The data acquisition module acquires the real-time status data of the battery pack at the time point, the data broadcasting module broadcasts the real-time status data using Bluetooth low energy technology, and the receiving and evaluating terminal evaluates the status of the battery pack according to the real-time status data; after receiving the initial status data, the receiving and evaluating terminal selects a matching charging status change model or a discharging status change model according to the charging and discharging status in the initial status data and the initial temperature, and determines the time point when the voltage or current change of the battery pack exceeds the set threshold according to the charging status change model or the discharging status change model.

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