Integrated aviation lithium storage battery system and BMS-dominated charging control method

Abstract

The invention discloses an integrated aviation lithium storage battery system and a BMS dominated charging control method, and belongs to the technical field of lithium storage battery charging, and the integrated aviation lithium storage battery system comprises a BMS module used for detecting the state of a charger and a charger control unit used for controlling the charger to work; the BPCU module is used for waking up the BMS module and the charger control unit, the CAN bus is used for transmitting CAN signals, the CAN hard wire is used for transmitting discrete signals, and the two ends of the BPCU module, the two ends of the BMS module and the two ends of the charger control unit are all connected with the CAN bus. Through the mode, the integrated lithium battery BMS, the charger control unit and the BPCU communication architecture provided by the invention can highly integrate communication among the lithium battery BMS, the charger control unit and the BPCU to the battery BMS on the premise of reserving design redundancy, and can reduce total communication wiring harnesses among the lithium battery BMS, the charger control unit and the BPCU, so that the cost is reduced on the premise of ensuring the design redundancy.

Description

Technical Field

[0001] The present invention relates to the technical field of lithium battery charging, and in particular to an integrated aviation lithium battery system and a charging control method led by a BMS. Background Art

[0002] The battery system of fixed-wing aircraft is mainly used to start the APU and emergency power supply when the onboard power generation device cannot operate. Lithium batteries have great prospects in the application of fixed-wing aircraft battery systems due to their advantages of energy density and low maintenance cost. The lithium battery system mainly includes lithium battery modules, BMS and chargers. Compared with the more mature aviation nickel-cadmium battery system, the lithium battery system has a higher theoretical risk of thermal runaway and a more complex electrical architecture. It is necessary to reduce system costs while ensuring safety redundancy.

[0003] Defects and deficiencies of existing technologies: There are two main types of electrical architectures for existing lithium battery systems. One is to integrate the battery control function into the charger control unit and BPCU (Bus Power Control Unit), and only retain the acquisition module in the battery pack. This architecture separates the traditional BMS main board and slave board modules, adding additional BMS master-slave communication costs. The other is that the battery BMS (Battery Management System) and the charger independently complete the communication with the BPCU and the policy control of their respective functions. The communication is mainly based on CAN (CAN Controller Area Network) and supplemented by hard wires. Since the physical distance between the battery system and the BPCU is generally far, each is connected to the BPCU with multiple hard wires, which will increase the overall material cost.

[0004] Based on this, the present invention designs an integrated aviation lithium battery system and a BMS-dominated charging control method to solve the above problems. Summary of the invention

[0005] In view of the above-mentioned shortcomings of the prior art, the present invention provides an integrated aviation lithium battery system and a BMS-dominated charging control method.

[0006] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0007] An integrated aviation lithium battery system includes a BMS module for detecting a charger status and a charger control unit for controlling the operation of the charger;

[0008] It also includes a BPCU module for waking up the BMS module and the charger control unit, a CAN bus for transmitting CAN signals, and a CAN hard line for transmitting discrete signals, and both ends of the BPCU module, both ends of the BMS module, and both ends of the charger control unit are connected to the CAN bus;

[0009] The BPCU module is connected to the BMS module via a CAN hard line, and the BMS module is connected to the charger control unit via a CAN hard line;

[0010] The BPCU module, BMS module and charger control unit transmit CAN signals via the CAN bus;

[0011] The CAN hard wire includes an internal hard wire and an external hard wire;

[0012] The BPCU module transmits discrete signals to the BMS module via external hard wires, and the BMS module transmits discrete signals to the BPCU module via internal hard wires;

[0013] The BMS module transmits discrete signals to the charger control unit via external hard wires, and the charger control unit transmits discrete signals to the BMS module via internal hard wires.

[0014] Furthermore, there are three internal hard wires and four external hard wires.

[0015] Furthermore, there are two external hard wires and two internal hard wires between the BPCU module and the BMS module.

[0016] Furthermore, there is one internal hard wire between the BMS module and the charger control unit, and there are two external hard wires between the BMS module and the charger control unit.

[0017] Furthermore, the discrete signals transmitted by the BPCU module to the BMS module are: waking up the BMS module, requesting the charger control unit to charge or prohibiting charging;

[0018] The discrete signals transmitted by the BMS module to the BPCU module are: request to disconnect the contactor, normal or abnormal charger.

[0019] Furthermore, the discrete signals transmitted by the BMS module to the charger control unit are: waking up the charger control unit, requiring the charger control unit to charge, or prohibiting charging;

[0020] The discrete signal transmitted by the charger control unit to the BMS module is: the charger is normal or abnormal.

[0021] Furthermore, the CAN signals transmitted by the BPCU module to the BMS module are: waking up the BMS module, requesting the charger control unit to charge or prohibiting charging;

[0022] The CAN signals transmitted by the BMS module to the BPCU module are: battery voltage, current, temperature and battery fault code.

[0023] Furthermore, the CAN signal transmitted by the BPCU module to the charger control unit is: waking up the charger control unit;

[0024] The CAN signals transmitted by the charger control unit to the BPCU module are: charger fault code;

[0025] The CAN signals transmitted by the BMS module to the charger control unit are: requesting charging or prohibiting charging, and requiring charging current or voltage;

[0026] The CAN signal transmitted by the charger control unit to the BMS module is: the charger allows charging or does not allow charging.

[0027] In order to better achieve the purpose of the present invention, the present invention proposes a BMS-led charging control method based on an integrated aviation lithium battery system, including a charging start strategy and a charging disconnection strategy;

[0028] The charging start strategy includes the following steps:

[0029] S1, BPCU module (1) requests the battery to start charging;

[0030] S2, BMS module (2) evaluates whether the battery status is chargeable;

[0031] The battery can be charged to proceed to the next step;

[0032] If the battery cannot be charged, the BMS module sends a fault code indicating that the battery cannot be charged to the BPCU module;

[0033] S3, the BMS module requires the charger control unit to close the charger's MOS switch;

[0034] S4, the charger control unit feedbacks whether the charger allows charging;

[0035] If the charger allows charging, proceed to the next step;

[0036] If the charger does not allow charging, the charger control unit sends a fault code indicating that charging is not possible to the BPCU module;

[0037] S5, the BMS module sends the required current or voltage to the charger;

[0038] S6, the BMS module determines whether the charger completes the action as required by the current value;

[0039] The thread ends when the charger completes the action as required;

[0040] If the charger fails to complete the action as required, the BMS module sends a charging failure fault code to the BPCU module.

[0041] Furthermore, the charging disconnection strategy includes the following steps:

[0042] D1, BPCU module 1 requires that the battery be prohibited from charging;

[0043] D2, the BMS module requires the charger control unit to disconnect the charger MOS switch;

[0044] D3, BMS module determines whether the charger MOS switch is successfully disconnected through the current value;

[0045] If the charger MOS switch is successfully disconnected, the thread ends;

[0046] If the charger MOS switch fails to disconnect successfully, the BMS module sends a fault code indicating that charging cannot be turned off to the BPCU module.

[0047] Compared with the prior art, the present invention has the following beneficial effects: 1. The integrated aviation battery system electrical architecture and its supporting charging control method provided by the present invention can ensure the safety redundancy of signal transmission through the signal backup design of CAN and hard-wired discrete signals, and at the same time reduce the number of hard-wire harnesses through the integration of communication functions, thereby achieving a reduction in material costs under a certain redundancy design;

[0048] 2. The four redundant functions are the BPCU module's wake-up function for the BMS module and the charger control unit, the BPCU module's function of requesting or prohibiting charging, the charger's normal status reporting, and the BMS module's function of requesting the BPCU module to disconnect the contactor. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0050] Figure 1 The structure of an integrated aviation lithium battery system of the present invention is shown in FIG. Figure 1 ;

[0051] Figure 2 The structure of an integrated aviation lithium battery system of the present invention is shown in FIG. Figure 2 ;

[0052] Figure 3 It is a schematic diagram of CAN communication transmission signal of the present invention;

[0053] Figure 4 A flow chart of the charging start control strategy of the present invention;

[0054] Figure 5 Flow chart of the charging disconnection control strategy of the present invention.

[0055] The numbers in the figure represent:

[0056] 1. BPCU module; 2. BMS module; 3. Charger control unit; 4. CAN bus; 5. CAN hard wire; 51. Internal hard wire; 52. External hard wire. DETAILED DESCRIPTION

[0057] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0058] Embodiment 1: In some embodiments, please refer to the drawings of the specification Figure 1-Figure 3 , including a BMS module 2 for detecting the charger status and a charger control unit 3 for controlling the charger operation;

[0059] It also includes a BPCU module 1 for waking up the BMS module 2 and the charger control unit 3, a CAN bus 4 for transmitting CAN signals, and a CAN hard line 5 for transmitting discrete signals. Both ends of the BPCU module 1, both ends of the BMS module 2, and both ends of the charger control unit 3 are connected to the CAN bus 4;

[0060] The BPCU module 1 is connected to the BMS module 2 via a CAN hard line 5, and the BMS module 2 is connected to the charger control unit 3 via a CAN hard line 5;

[0061] CAN signals are transmitted between the BPCU module 1, the BMS module 2, and the charger control unit 3 via the CAN bus 4;

[0062] The present invention can ensure the safety redundancy of signal transmission through the signal backup design of the discrete signals of the CAN bus 4 and the CAN hard wire 5, and at the same time reduce the number of hard wire harnesses through the integration of communication functions, thereby achieving a reduction in material cost under a certain redundant design.

[0063] The CAN hard wire 5 includes an internal hard wire 51 and an external hard wire 52;

[0064] The BPCU module 1 transmits discrete signals to the BMS module 2 via an external hard line 52, and the BMS module 2 transmits discrete signals to the BPCU module 1 via an internal hard line 51;

[0065] The BMS module 2 transmits discrete signals to the charger control unit 3 via the external hard wire 52 , and the charger control unit 3 transmits discrete signals to the BMS module 2 via the internal hard wire 51 .

[0066] There are three internal hard wires 51 and four external hard wires 52 .

[0067] There are two external hard wires 52 and two internal hard wires 51 between the BPCU module 1 and the BMS module 2 .

[0068] There is one internal hard wire 51 between the BMS module 2 and the charger control unit 3 , and there are two external hard wires 52 between the BMS module 2 and the charger control unit 3 .

[0069] The discrete signals transmitted by the BPCU module 1 to the BMS module 2 are: waking up the BMS module 2, requesting the charger control unit 3 to charge or prohibiting charging;

[0070] The discrete signals transmitted by the BMS module 2 to the BPCU module 1 are: request to disconnect the contactor, and the charger is normal or abnormal.

[0071] The discrete signals transmitted by the BMS module 2 to the charger control unit 3 are: waking up the charger control unit 3, requiring the charger control unit 3 to charge or prohibiting charging;

[0072] The discrete signal transmitted by the charger control unit 3 to the BMS module 2 is: whether the charger is normal or abnormal.

[0073] The CAN signal transmitted by the BPCU module 1 to the BMS module 2 is: waking up the BMS module 2, requesting the charger control unit 3 to charge or prohibit charging;

[0074] The CAN signals transmitted by the BMS module 2 to the BPCU module 1 are: battery voltage, current, temperature and battery fault code.

[0075] The CAN signal transmitted by the BPCU module 1 to the charger control unit 3 is: waking up the charger control unit 3;

[0076] The CAN signal transmitted by the charger control unit 3 to the BPCU module 1 is: charger fault code;

[0077] The CAN signals transmitted by the BMS module 2 to the charger control unit 3 are: charging request or charging prohibition, charging current or voltage requirement;

[0078] The CAN signal transmitted by the charger control unit 3 to the BMS module 2 is: the charger allows charging or does not allow charging.

[0079] Embodiment 2: In some embodiments, Figure 4 and Figure 5 As shown, the present invention proposes a BMS-led charging control method based on an integrated aviation lithium battery system, including a charging start-up strategy and a charging disconnection strategy;

[0080] The charging start strategy includes the following steps:

[0081] S1, BPCU module 1 requires the battery to start charging;

[0082] S2, BMS module 2 evaluates whether the battery status is chargeable;

[0083] The battery can be charged to proceed to the next step;

[0084] If the battery cannot be charged, the BMS module 2 sends a fault code indicating that the battery cannot be charged to the BPCU module 1;

[0085] S3, BMS module 2 requires charger control unit 3 to close the charger MOS switch;

[0086] S4, the charger control unit 3 provides feedback on whether the charger allows charging;

[0087] If the charger allows charging, proceed to the next step;

[0088] If the charger does not allow charging, the charger control unit 3 sends a fault code indicating that charging is not possible to the BPCU module 1;

[0089] S5, BMS module 2 sends the required current or voltage to the charger;

[0090] S6, BMS module 2 determines whether the charger completes the action as required by the current value;

[0091] The thread ends when the charger completes the action as required;

[0092] If the charger fails to complete the action as required, the BMS module 2 sends a charging failure code to the BPCU module 1.

[0093] The charging disconnection strategy includes the following steps:

[0094] D1, BPCU module 1 requires that the battery be prohibited from charging;

[0095] D2, BMS module 2 requires charger control unit 3 to disconnect the charger MOS switch;

[0096] D3, BMS module 2 determines whether the charger MOS switch is successfully disconnected through the current value;

[0097] If the charger MOS switch is successfully disconnected, the thread ends;

[0098] If the charger MOS switch is not successfully disconnected, the BMS module 2 sends a fault code indicating that charging cannot be turned off to the BPCU module 1.

[0099] 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 the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such 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 embodiments of the present invention.

Claims

1. An integrated aviation lithium battery system, characterized in that: It comprises a BMS module (2) for detecting the status of a charger and a charger control unit (3) for controlling the operation of the charger; It also includes a BPCU module (1) for waking up a BMS module (2) and a charger control unit (3), a CAN bus (4) for transmitting CAN signals, and a CAN hard line (5) for transmitting discrete signals, wherein both ends of the BPCU module (1), both ends of the BMS module (2), and both ends of the charger control unit (3) are connected to the CAN bus (4); The BPCU module (1) is connected to the BMS module (2) via a CAN hard line (5), and the BMS module (2) is connected to the charger control unit (3) via a CAN hard line (5); The BPCU module (1), the BMS module (2) and the charger control unit (3) transmit CAN signals via a CAN bus (4); The CAN hard wire (5) comprises an internal hard wire (51) and an external hard wire (52); The BPCU module (1) transmits a discrete signal to the BMS module (2) via an external hard line (52), and the BMS module (2) transmits a discrete signal to the BPCU module (1) via an internal hard line (51); The BMS module (2) transmits a discrete signal to the charger control unit (3) via an external hard line (52), and the charger control unit (3) transmits a discrete signal to the BMS module (2) via an internal hard line (51).

2. The integrated aviation lithium battery system according to claim 1, characterized in that: There are three internal hard wires (51) and four external hard wires (52).

3. The integrated aviation lithium battery system according to claim 2, characterized in that: There are two external hard wires (52) and two internal hard wires (51) between the BPCU module (1) and the BMS module (2).

4. The integrated aviation lithium battery system according to claim 3, characterized in that: One internal hard wire (51) is provided between the BMS module (2) and the charger control unit (3), and two external hard wires (52) are provided between the BMS module (2) and the charger control unit (3).

5. The integrated aviation lithium battery system according to claim 4, characterized in that: The discrete signals transmitted by the BPCU module (1) to the BMS module (2) are: waking up the BMS module (2), requesting the charger control unit (3) to charge or prohibiting charging; The discrete signals transmitted by the BMS module (2) to the BPCU module (1) are: request to disconnect the contactor, and the charger is normal or abnormal.

6. The integrated aviation lithium battery system according to claim 5, characterized in that: The discrete signals transmitted by the BMS module (2) to the charger control unit (3) are: waking up the charger control unit (3), requesting the charger control unit (3) to charge or prohibiting charging; The discrete signal transmitted by the charger control unit (3) to the BMS module (2) is: whether the charger is normal or abnormal.

7. The integrated aviation lithium battery system according to claim 6, characterized in that: The CAN signal transmitted by the BPCU module (1) to the BMS module (2) is: waking up the BMS module (2) and requesting the charger control unit (3) to charge or prohibit charging; The CAN signals transmitted by the BMS module (2) to the BPCU module (1) are: battery voltage, current, temperature and battery fault code.

8. The integrated aviation lithium battery system according to claim 7, characterized in that: The CAN signal transmitted by the BPCU module (1) to the charger control unit (3) is: waking up the charger control unit (3); The CAN signal transmitted by the charger control unit (3) to the BPCU module (1) is: charger fault code; The CAN signal transmitted by the BMS module (2) to the charger control unit (3) is: requesting charging or prohibiting charging, and requiring charging current or voltage; The CAN signal transmitted by the charger control unit (3) to the BMS module (2) is: the charger allows charging or does not allow charging.

9. The BMS-led charging control method for the integrated aviation lithium battery system according to claim 8, characterized in that: Including charging start strategy and charging disconnection strategy; The charging start strategy includes the following steps: S1, BPCU module (1) requests the battery to start charging; S2, BMS module (2) evaluates whether the battery status is chargeable; The battery can be charged to proceed to the next step; If the battery cannot be charged, the BMS module (2) sends a charging failure code to the BPCU module (1); S3, the BMS module (2) requests the charger control unit (3) to close the MOS switch of the charger; S4, the charger control unit (3) feedbacks whether the charger allows charging; If the charger allows charging, proceed to the next step; If the charger does not allow charging, the charger control unit (3) sends a charging failure code to the BPCU module (1); S5, the BMS module (2) sends the required current or voltage to the charger; S6, the BMS module (2) determines whether the charger completes the action as required based on the current value; The charger completes the action as required and ends the thread; If the charger fails to complete the action as required, the BMS module (2) sends a charging failure code to the BPCU module (1).

10. The BMS-led charging control method according to claim 9, characterized in that: The charging disconnection strategy includes the following steps: D1, BPCU module 1 requires that the battery be prohibited from charging; D2, the BMS module (2) requests the charger control unit (3) to disconnect the charger MOS switch; D3, BMS module (2) determines whether the charger MOS switch is successfully disconnected based on the current value; If the charger MOS switch is successfully disconnected, the thread ends; If the charger MOS switch is not successfully disconnected, the BMS module (2) sends a fault code indicating that charging cannot be turned off to the BPCU module (1).

Images