An aviation battery system with parallel battery packs and BMS backing up each other

Abstract

The present invention discloses an aviation battery system in which parallel battery packs BMS back up each other, belonging to the field of battery control technology. The four battery sub-packs of the present invention are in parallel form, and the high-voltage bus converges on the same bus. The four battery packs provide power to all motors as a whole. The four battery sub-packs communicate with the flight controller using a dual-channel CAN bus to achieve communication redundancy. The high-voltage connector drive of a single battery sub-pack is backed up by another battery sub-pack, that is, BMS_2 backs up the high-voltage connector drive of BMS_1, BMS_3 backs up BMS_2, BMS_4 backs up BMS_3, and BMS_1 backs up BMS_4. The present invention greatly improves the safety of the aviation battery system by backing up the high-voltage connector drives of the four battery sub-packs, and realizes the redundant design of battery whole pack state estimation and high-voltage connector drive backup without increasing hardware costs, greatly reducing product costs.

Description

Technical Field

[0001] The present invention relates to the field of battery control technology, and in particular to an aviation battery system in which parallel battery packs (BMSs) serve as backup for each other. Background Art

[0002] With the continuous improvement of battery energy density and safety, power batteries are increasingly being used in the aviation field. Low-altitude electric vertical take-off and landing (EVTOL) aircraft have seen rapid development in recent years, especially in the recent past. Unlike automotive power batteries, aviation power batteries have higher safety requirements. To achieve these high safety requirements, multiple battery packs are typically used to power aircraft. Therefore, a system solution for effectively managing these multiple battery packs is particularly important.

[0003] Existing electric aircraft battery systems mostly use a parallel architecture, with each battery pack controlled by an independent BMS. In addition, a battery system control unit communicates with each BMS, collecting and processing information from each battery pack's BMS to determine the capacity of the entire battery system. This battery system control unit is also responsible for communicating with the flight controller, providing the flight controller with key battery pack information required, such as available energy, power, and thermal runaway alarms.

[0004] Due to the high safety requirements of the aviation industry, this solution requires two backup controllers for redundant control of the battery system control unit. Due to the high cost of controllers in the aviation industry, this solution significantly increases company costs. Furthermore, since each battery pack's high-voltage connector driver also requires a backup for redundant control, wiring from the battery system control unit to each battery pack is required, increasing the complexity of the battery system cabling, which can easily cause confusion and compromise system safety.

[0005] Based on this, the present invention designs an aviation battery system in which parallel battery packs (BMSs) serve as backup for each other to solve the above problems. Summary of the Invention

[0006] In view of the above-mentioned shortcomings of the prior art, the present invention provides an aviation battery system in which parallel battery packs (BMSs) serve as backup for each other.

[0007] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0008] An aviation battery system with parallel battery packs and BMSs serving as backup for each other, including a battery pack, which includes four battery sub-packs;

[0009] The four battery subpacks include BMS_1, BMS_2, BMS_3 and BMS_4, which are connected in parallel via the CAN bus, which is connected to the flight controller.

[0010] BMS_1 is connected to high-voltage connector 1, BMS_2 is connected to high-voltage connector 2, BMS_3 is connected to high-voltage connector 3, and BMS_4 is connected to high-voltage connector 4;

[0011] BMS_1 is connected to high-voltage connector 4, BMS_2 is connected to high-voltage connector 1, BMS_3 is connected to high-voltage connector 2, and BMS_4 is connected to high-voltage connector 3;

[0012] BMS_1, BMS_2, BMS_3 and BMS_4 perform validity calculations and upload the results of the validity calculations to the CAN bus;

[0013] BMS_1, BMS_2, BMS_3 and BMS_4 calculate the key information corresponding to BMS_1, BMS_2, BMS_3 and BMS_4 respectively based on the results of the validity calculation;

[0014] BMS_1, BMS_2, BMS_3, and BMS_4 upload the validity calculation results and key information to the CAN bus, which is then uploaded to the flight controller via the CAN bus.

[0015] Then BMS_1 uploads the key information to the CAN bus. At the same time, BMS_1 receives the key information sent by BMS_2, BMS_3 and BMS_4 on the CAN bus. BMS_1 then calculates the key information of the entire battery pack based on the key information uploaded by BMS_2, BMS_3 and BMS_4. At the same time, based on the effective status of BMS_2 and BMS_4, it backs up the corresponding high-voltage connectors.

[0016] The calculation method and data transmission process of BMS_2, BMS_3 and BMS_4 are similar;

[0017] The flight controller receives the validity calculation results and key information of BMS_1, BMS_2, BMS_3, and BMS_4 on the CAN bus, and decides to use the whole package of key information provided by the corresponding BMS_1, BMS_2, BMS_3, and BMS_4 based on the validity of BMS_1, BMS_2, BMS_3, and BMS_4.

[0018] After power-on, the battery sub-pack BMS first performs a validity calculation. If it is valid, it starts to calculate the key information of the battery sub-pack (SOC value, SOP value, high-voltage connector status, thermal runaway status), and then sends the key information of the battery sub-pack to the CAN bus. At the same time, it receives the key information sent by the other three battery sub-packs to the CAN bus, calculates the key information of the entire battery pack based on the key information of each battery sub-pack, and at the same time, backs up the high-voltage connector of the adjacent battery sub-pack based on its valid status.

[0019] Furthermore, the key information of BMS_1, BMS_2, BMS_3 and BMS_4 includes SOC value, SOP value, high voltage connector status and thermal runaway status.

[0020] Furthermore, the flight controller's control logic for the effectiveness of BMS_1, BMS_2, BMS_3, and BMS_4 is as follows:

[0021] If BMS_1 is valid, the flight controller uses the key information of the entire battery pack provided by BMS_1;

[0022] If BMS_1 is invalid, determine whether BMS_2 is valid. If BMS_2 is valid, use the key information of the entire battery pack provided by BMS_2.

[0023] If BMS_2 is invalid, the validity of BMS_3 is determined. If BMS_3 is valid, the key information of the entire battery pack provided by BMS_3 is used.

[0024] If BMS_3 is invalid, determine whether BMS_4 is valid. If so, use the key information of the entire battery pack provided by BMS_4. Otherwise, enter the emergency processing procedure.

[0025] Furthermore, the logic of the battery pack controller to determine the invalid status of BMS_1, BMS_2, BMS_3, and BMS_4 is as follows:

[0026] 1. The power supply voltage of BMS_1, BMS_2, BMS_3, and BMS_4 is abnormal;

[0027] 2. MCU watchdog exception in BMS_1, BMS_2, BMS_3, and BMS_4;

[0028] 3. BMS_1, BMS_2, BMS_3, and BMS_4 experienced core lockstep comparison anomalies. Core lockstep comparison is a technology used in computer systems to improve reliability and security, primarily in dual-core lockstep chips. The basic principle of core lockstep comparison is to use two identical microcontrollers (MCUs), access the same instructions and data from the same bus, execute the same program at the same clock cycle, and periodically compare the outputs of the two MCUs for consistency.

[0029] Furthermore, the abnormal situation of the power supply voltage of BMS_1, BMS_2, BMS_3, and BMS_4 is that the power supply voltage of BMS_1, BMS_2, BMS_3, and BMS_4 exceeds the voltage range of 25.2V-30.8V.

[0030] Furthermore, the abnormal situation of the MCU watchdog of BMS_1, BMS_2, BMS_3, and BMS_4 is: the MCU does not feed the dog for two consecutive cycles.

[0031] Furthermore, the core lockstep comparison abnormality is that the dual cores are inconsistent and fail to recover within 10ms.

[0032] Furthermore, the calculation method of the battery pack SOC value is as follows: BMS_1, BMS_2, BMS_3 and BMS_4 will obtain the SOC values ​​of the corresponding battery sub-packs and compare them, and select the minimum value as the battery pack SOC value;

[0033] Calculate the average SOC value of the corresponding battery sub-packs of BMS_1, BMS_2, BMS_3 and BMS_4. If the SOC value of a single battery sub-pack deviates from the average SOC value by more than 5%, the SOC value of the battery sub-pack is determined to be abnormal. The abnormal battery sub-pack SOC value is not included in the calculation of the SOC value of the entire battery pack, and a warning of abnormal SOC value status of the battery sub-pack is sent to the flight controller, requesting the aircraft to land for inspection. At the same time, BMS_1, BMS_2, BMS_3 and BMS_4 send the calculated SOC value information of the entire battery pack to the CAN bus.

[0034] Furthermore, the SOP value calculation method of the whole battery pack is as follows: BMS_1, BMS_2, BMS_3 and BMS_4 will obtain the SOP values ​​of the corresponding battery sub-packs and compare them, select the minimum value as the basis for calculating the SOP value, multiply this basic value by the number of battery sub-packs to obtain the SOP value of the whole battery pack, and send the SOP value of the whole battery pack to the CAN bus;

[0035] If the calculated SOP value of the entire battery pack of BMS_1, BMS_2, BMS_3 and BMS_4 is less than the minimum power required for landing (the power is provided by the aircraft), a warning message of the low SOP value of the entire battery pack of the system is sent to the CAN bus to request the aircraft to land for inspection.

[0036] Furthermore, the high-voltage connector status is determined: when the aircraft is in flight, if the flight controller detects that any high-voltage connector is open, it prohibits the opening of the remaining high-voltage connectors, sends a warning about the abnormal status of the high-voltage connector of the battery subpack, and requests the aircraft to land for inspection;

[0037] Thermal runaway status judgment: When the flight controller detects that a battery sub-pack has thermal runaway, it disconnects the high-voltage connector of the battery sub-pack and prohibits the high-voltage connectors of other battery sub-packs from being disconnected. It also sends a thermal runaway warning for the battery sub-pack and requests the aircraft to land for inspection.

[0038] Compared with the prior art, the present invention has the following beneficial effects: 1. The present invention designs a high-safety battery pack parallel system solution, which realizes the safety backup of the whole pack state estimation;

[0039] 2. The present invention significantly improves the safety of the aviation battery system by backing up each other through the four battery sub-pack high-voltage connectors;

[0040] 3. The present invention realizes redundant design of battery pack status estimation and high-voltage connector drive backup without increasing hardware costs, which greatly reduces product costs. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive effort.

[0042] Figure 1 This is a connection block diagram of an aviation battery system with parallel battery packs and BMSs serving as backup for each other according to the present invention;

[0043] Figure 2 This is a system flow chart of an aviation battery system with parallel battery packs and BMSs serving as backup for each other according to the present invention;

[0044] Figure 3 The figure is a flow chart for determining the effectiveness of an aviation battery system in which parallel battery packs (BMSs) serve as backup for each other according to the present invention. DETAILED DESCRIPTION

[0045] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making any creative efforts shall fall within the scope of protection of the present invention.

[0046] Example 1: In some embodiments, please refer to the accompanying drawings of the specification. Figure 1-Figure 3 , including a battery pack, which includes four battery sub-packs;

[0047] The four battery subpacks include BMS (Battery Management System) 1, BMS_2, BMS_3 and BMS_4, which are connected in parallel via CAN (Controller Area Network) bus, and the CAN bus is connected to the flight controller.

[0048] BMS_1 is connected to high-voltage connector 1, BMS_2 is connected to high-voltage connector 2, BMS_3 is connected to high-voltage connector 3, and BMS_4 is connected to high-voltage connector 4;

[0049] BMS_1 is connected to high-voltage connector 4, BMS_2 is connected to high-voltage connector 1, BMS_3 is connected to high-voltage connector 2, and BMS_4 is connected to high-voltage connector 3;

[0050] BMS_1, BMS_2, BMS_3 and BMS_4 perform validity calculations and upload the results of the validity calculations to the CAN bus;

[0051] BMS_1, BMS_2, BMS_3 and BMS_4 respectively calculate the key information corresponding to BMS_1, BMS_2, BMS_3 and BMS_4 according to the results of the effectiveness calculation; the key information of BMS_1, BMS_2, BMS_3 and BMS_4 includes SOC (State Of Charge, battery state of charge value), SOP (State Of Power, battery charge and discharge power state value, high voltage connector status and thermal runaway status.

[0052] Then BMS_1 uploads the key information to the CAN bus. At the same time, BMS_1 receives the key information sent by BMS_2, BMS_3 and BMS_4 on the CAN bus. BMS_1 then calculates the key information of the entire battery pack based on the key information uploaded by BMS_2, BMS_3 and BMS_4. At the same time, based on the effective status of BMS_2 and BMS_4, it backs up the corresponding high-voltage connectors.

[0053] The calculation method and data transmission process of BMS_2, BMS_3 and BMS_4 are similar;

[0054] The flight controller receives the validity calculation results and key information of BMS_1, BMS_2, BMS_3, and BMS_4 on the CAN bus, and decides to use the whole package of key information provided by the corresponding BMS_1, BMS_2, BMS_3, and BMS_4 based on the validity of BMS_1, BMS_2, BMS_3, and BMS_4.

[0055] The flight controller's control logic for the effectiveness of BMS_1, BMS_2, BMS_3, and BMS_4 is as follows:

[0056] If BMS_1 is valid, the flight controller uses the entire package of key information provided by BMS_1;

[0057] If BMS_1 is invalid, determine whether BMS_2 is valid. If BMS_2 is valid, use the entire package of key information provided by BMS_2.

[0058] If BMS_2 is invalid, the validity of BMS_3 is determined. If BMS_3 is valid, the entire package of key information provided by BMS_3 is used.

[0059] If BMS_3 is invalid, determine whether BMS_4 is valid. If so, use the entire package of key information provided by BMS_4. Otherwise, enter the emergency processing procedure.

[0060] The logic of the battery pack controller to determine the invalid status of BMS_1, BMS_2, BMS_3, and BMS_4 is as follows:

[0061] 1. Abnormal power supply voltage of BMS_1, BMS_2, BMS_3, and BMS_4: The power supply voltage of BMS_1, BMS_2, BMS_3, and BMS_4 exceeds the voltage range of 25.2V-30.8V.

[0062] 2. The MCU (Microcontroller Uni t) in BMS_1, BMS_2, BMS_3, and BMS_4 has a watchdog failure: the MCU has not fed the watchdog for two consecutive cycles.

[0063] 3. The lockstep of BMS_1, BMS_2, BMS_3, and BMS_4 cores is abnormal: the two cores are inconsistent and do not recover within 10ms.

[0064] Core lockstep comparison is a technology used to improve reliability and security in computer systems, primarily in dual-core lockstep chips. The basic principle of core lockstep comparison is to use two identical microcontrollers (MCUs), access the same instructions and data from the same bus, execute the same program at the same clock cycle, and periodically compare the outputs of the two MCUs to ensure consistency.

[0065] After power-on, the sub-pack BMS first performs a validity calculation. If valid, it starts to calculate the sub-pack key information, then sends the sub-pack key information to the CAN bus, and at the same time receives the key information sent to the CAN bus by the other three BMSs. The key information of the entire pack is calculated based on the key information of each sub-pack, and the high-voltage connector of the adjacent sub-pack is backed up and driven according to the valid status of the adjacent sub-pack BMS.

[0066] Embodiment 2: In some embodiments, as Figure 1-Figure 3 As shown in FIG. 1 , as a preferred embodiment of the present invention, a method for calculating the SOC value of the entire battery pack is as follows: BMS_1, BMS_2, BMS_3, and BMS_4 obtain the SOC values ​​of the corresponding battery sub-packs and compare them, and select the minimum value as the SOC value of the entire battery pack;

[0067] Calculate the average SOC value of the corresponding battery sub-packs of BMS_1, BMS_2, BMS_3 and BMS_4. If the SOC value of a single battery sub-pack deviates from the average SOC value by more than 5%, the SOC value of the battery sub-pack is determined to be abnormal. The abnormal battery sub-pack SOC value is not included in the calculation of the SOC value of the entire battery pack, and a warning of abnormal SOC value status of the battery sub-pack is sent to the flight controller, requesting the aircraft to land for inspection. At the same time, BMS_1, BMS_2, BMS_3 and BMS_4 send the calculated SOC value information of the entire battery pack to the CAN bus.

[0068] Calculation method of the SOP value of the whole battery pack: BMS_1, BMS_2, BMS_3 and BMS_4 will obtain the SOP values ​​of the corresponding battery sub-packs and compare them. The minimum value is selected as the basis for calculating the SOP value. This basic value is multiplied by the number of battery sub-packs to obtain the SOP value of the whole battery pack. The SOP value of the whole battery pack is sent to the CAN bus.

[0069] If the calculated SOP value of the entire battery pack of BMS_1, BMS_2, BMS_3 and BMS_4 is less than the minimum power required for landing (the power is provided by the aircraft), a warning message of the low SOP value of the entire battery pack of the system is sent to the CAN bus to request the aircraft to land for inspection.

[0070] High-voltage connector status judgment: When the aircraft is in flight, if the flight controller detects that any high-voltage connector is open, it will prohibit the opening of other high-voltage connectors, send a warning about the abnormal status of the high-voltage connector of the battery subpack, and request the aircraft to land for inspection;

[0071] Thermal runaway status judgment: When the flight controller detects that a battery sub-pack has thermal runaway, it disconnects the high-voltage connector of the battery sub-pack and prohibits the high-voltage connectors of other battery sub-packs from being disconnected. It also sends a thermal runaway warning for the battery sub-pack and requests the aircraft to land for inspection.

[0072] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the various embodiments of the present invention.

Claims

1. An aviation battery system with parallel battery packs and BMS backing up each other, characterized by: Including a battery pack, the battery pack includes four battery sub-packs; The four battery subpacks include (BMS_1), (BMS_2), (BMS_3) and (BMS_4), respectively. The (BMS_1), (BMS_2), (BMS_3) and (BMS_4) are connected in parallel via a CAN bus, and the CAN bus is connected to the flight controller; (BMS_1) is connected to the high-voltage connector (1), (BMS_2) is connected to the high-voltage connector (2), (BMS_3) is connected to the high-voltage connector (3), and (BMS_4) is connected to the high-voltage connector (4); (BMS_1) is connected to the high-voltage connector (4), (BMS_2) is connected to the high-voltage connector (1), (BMS_3) is connected to the high-voltage connector (2), and (BMS_4) is connected to the high-voltage connector (3); (BMS_1), (BMS_2), (BMS_3) and (BMS_4) perform validity calculations and upload the results of the validity calculations to the CAN bus; (BMS_1), (BMS_2), (BMS_3) and (BMS_4) respectively calculate the key information corresponding to (BMS_1), (BMS_2), (BMS_3) and (BMS_4) according to the results of the validity calculation; Then (BMS_1) uploads the key information to the CAN bus, and (BMS_1) receives the key information sent to the CAN bus by (BMS_2), (BMS_3) and (BMS_4). (BMS_1) calculates the key information of the entire battery pack based on the key information uploaded by (BMS_2), (BMS_3) and (BMS_4), and backs up the corresponding high-voltage connectors based on the effective status of (BMS_2) and (BMS_4); The flight controller receives the validity calculation results and key information of (BMS_1), (BMS_2), (BMS_3), (BMS_4) on the CAN bus, and decides to adopt the whole package of key information provided by (BMS_1), (BMS_2), (BMS_3), (BMS_4) according to the validity of (BMS_1), (BMS_2), (BMS_3), (BMS_4).

2. The aviation battery system with parallel battery packs and BMS backing up each other according to claim 1 is characterized in that: The key information of (BMS_1), (BMS_2), (BMS_3) and (BMS_4) includes SOC value, SOP value, high voltage connector status and thermal runaway status.

3. The aviation battery system with parallel battery packs and BMS backing up each other according to claim 2 is characterized in that: The flight controller's control logic for the effectiveness of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) is as follows: If (BMS_1) is valid, the flight controller uses the key information of the battery pack provided by (BMS_1); If (BMS_1) is invalid, determine whether (BMS_2) is valid. If (BMS_2) is valid, use the key information of the entire battery pack provided by (BMS_2); If (BMS_2) is invalid, then determine the validity of (BMS_3). If (BMS_3) is valid, then use the key information of the entire battery pack provided by (BMS_3); If (BMS_3) is invalid, determine whether (BMS_4) is valid. If it is valid, use the key information of the entire battery pack provided by (BMS_4). If (BMS_4) is invalid, enter the emergency processing procedure.

4. The aviation battery system with parallel battery packs and BMS backing up each other according to claim 3 is characterized in that: The logic of the battery pack controller to determine the invalid state of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) is as follows:

1. The power supply voltage of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) is abnormal; 2. MCU watchdog abnormality in (BMS_1), (BMS_2), (BMS_3), and (BMS_4); 3. The nuclear lock-step of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) is quite abnormal.

5. The aviation battery system with parallel battery packs BMS backing up each other according to claim 4 is characterized in that: The abnormal situation of the power supply voltage of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) is: the power supply voltage of (BMS_1), (BMS_2), (BMS_3), and (BMS_4) exceeds the voltage range of 25.2V-30.8V.

6. The aviation battery system with parallel battery packs and BMS backing up each other according to claim 5, characterized in that: The abnormal situation of the MCU watchdog of (BMS_1), (BMS_2), (BMS_3) and (BMS_4) is: the MCU does not feed the watchdog for two consecutive cycles.

7. The aviation battery system with parallel battery packs and BMS backing up each other according to claim 6, characterized in that: The core lockstep comparison abnormality is: the dual cores are inconsistent and fail to recover within 10ms.

8. The aviation battery system with parallel battery packs BMS backing up each other according to claim 7, characterized in that: Calculation method of the SOC value of the whole battery pack: (BMS_1), (BMS_2), (BMS_3) and (BMS_4) compare the SOC values ​​of the corresponding battery sub-packs and select the minimum value as the SOC value of the whole battery pack; Calculate the average SOC value of the corresponding battery sub-packs of (BMS_1), (BMS_2), (BMS_3) and (BMS_4). If the SOC value of a single battery sub-pack deviates from the average SOC value by more than 5%, the SOC value of the battery sub-pack is determined to be abnormal. The abnormal SOC value of the battery sub-pack does not participate in the calculation of the SOC value of the entire battery pack, and sends a warning of abnormal SOC value status of the battery sub-pack to the flight controller, requesting the aircraft to land for inspection. At the same time, (BMS_1), (BMS_2), (BMS_3) and (BMS_4) send the calculated SOC value information of the entire battery pack to the CAN bus.

9. The aviation battery system with parallel battery packs BMS backing up each other according to claim 8, characterized in that: Calculation method of SOP value of the whole battery pack: (BMS_1), (BMS_2), (BMS_3) and (BMS_4) will obtain the SOP values ​​of the corresponding battery sub-packs for comparison, select the minimum value as the calculation basis of the SOP value, multiply this basic value by the number of battery sub-packs to obtain the SOP value of the whole battery pack, and send the SOP value of the whole battery pack to the CAN bus; If the calculated SOP value of the whole battery pack is less than the minimum power required for landing, (BMS_1), (BMS_2), (BMS_3) and (BMS_4) send a low SOP value warning message to the CAN bus to request the aircraft to land.

10. The aviation battery system with parallel battery packs BMS backing up each other according to claim 9, characterized in that: High-voltage connector status judgment: When the aircraft is in flight, if the flight controller detects that any high-voltage connector is open, it prohibits the opening of other high-voltage connectors, sends an abnormal status warning for the high-voltage connector of the battery subpack, and requests the aircraft to land for inspection; Thermal runaway status judgment: When the flight controller detects that a battery sub-pack has thermal runaway, it disconnects the high-voltage connector of the battery sub-pack, prohibits the high-voltage connectors of other battery sub-packs from being disconnected, and sends a thermal runaway warning for the battery sub-pack, requesting the aircraft to land for inspection.

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