High-safety aviation power battery system

Abstract

The invention discloses a high-safety aviation power battery system, and belongs to the technical field of power battery design, the high-safety aviation power battery system comprises at least one battery pack and a backup module loop, and in a normal working condition, the battery pack (PACK) is not connected with the backup module loop; when an abnormal working condition occurs, the battery pack (PACK) is connected in series with the backup module loop; the battery pack comprises an electrical loop and a pre-charging loop; one end of the electrical loop is connected with the pre-charging loop, and the other end of the electrical loop is electrically connected with the backup module loop. Through the mode, the problem that a whole pack is lost after a single battery cell fails can be solved by using one backup module, a plurality of battery packs can share the same backup module so as to realize income maximization, the backup module is generally low in voltage, and the backup module can be used for low-voltage power supply backup of a BMS after being additionally provided with a small DCDC, so that the system safety is further improved; meanwhile, the system dead weight is further reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of power battery design, and in particular to a high-safety aviation power battery system. Background Art

[0002] In the field of aircraft, for safety reasons, redundant backup is performed on the core power battery to meet the reliability requirements of the entire power system. Generally, 3-10 sub-packs form a power system. If one of the cells experiences thermal runaway, the sub-pack will be short-circuited or actively cut off the power of the relay. If the entire system loses one of the sub-packs, the remaining sub-packs continue to provide power for the aircraft to land safely.

[0003] Especially in the field of eVTOL, the power demand for vertical takeoff and landing of aircraft is particularly high, generally up to 4-6C, and the time is as long as 30s-120s. After losing a sub-packet, the remaining sub-packets continue to provide the power demand for safe landing. The current required by the single battery cell of the remaining sub-packet becomes larger. Redundancy design of power capacity is required during the initial design of the battery cell. If the number of sub-packets is 4, the power capacity needs to be redundant by 33%; if the number of sub-packets is 5, the power capacity needs to be redundant by 25%; if the number of sub-packets is 6, the power capacity needs to be redundant by 20%.

[0004] There are six major dimensions in battery cell design: energy density, power, fast charging, cycle, safety, and cost. When the power demand is already very high, the power capacity of the battery cell must be redundantly designed to cope with emergency scenarios. Further raising the power requirements for the battery cell, the emphasis on a single performance indicator will inevitably partially sacrifice performance in other aspects.

[0005] After a single sub-pack fails, the overcurrent demand of the remaining sub-packs increases. In addition to the redundant design of the battery cells, the battery pack and the entire power system also need corresponding redundant designs to jointly cope with emergency scenarios.

[0006] Based on this, the present invention designs a high-safety aviation power battery system to solve the above problems. Summary of the invention

[0007] In view of the above-mentioned shortcomings of the prior art, the present invention provides a high-safety aviation power battery system.

[0008] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0009] A high-safety aviation power battery system, comprising at least one battery pack and a backup module circuit;

[0010] Under normal working conditions, the battery pack (PACK) is not connected to the backup module circuit;

[0011] When an abnormal operating condition occurs, the battery pack (PACK) is connected in series with the backup module circuit;

[0012] The battery pack includes an electrical circuit and a pre-charging circuit;

[0013] One end of the electrical circuit is connected to the pre-charging circuit, and the other end of the electrical circuit is electrically connected to the backup module circuit.

[0014] Furthermore, the electrical circuit includes n modules, and the n modules are module M1, module M2, module M3, ... module M n-1 and module M n , the module M1, module M2, module M3...module M n-1 and module M n Connect in series one by one.

[0015] Furthermore, the electrical circuit includes n+1 switches, and the n+1 switches are switch K1, switch K2, switch K3, ..., switch K4, switch K5, switch K6, switch K7, switch K8, switch K9, switch K10, switch K111, switch K122, switch K13, switch K143, switch K154, switch K165, switch K176, switch K187, switch K190, switch K201, switch K3 n-1 , switch K n and switch K n+1， The switch K1, switch K2, switch K3, ... switch K n-1 , switch K n and switch K n+1 The two ends of the module M1 are electrically connected to the switch K1 and the switch K2 respectively, and the two ends of the module M2 are electrically connected to the switch K2 and the switch K3 respectively. n The two ends of the switch K n , switch K n+1 Electrical connection.

[0016] Furthermore, the backup module circuit includes a backup module M backup And backup module dedicated relay K b .

[0017] Furthermore, the main negative relay K main negative is arranged in the electrical circuit or the backup module circuit.

[0018] Furthermore, the main negative relay K 主负 One end of the switch K n+1 、Module M n Electrical connection, main negative relay K 主负 The other end is connected to the backup module dedicated relay K b One end of the backup module is electrically connected to the dedicated relay K b The other end and the backup module M backup One end of the backup module M is electrically connected to backup The other end of the module M n , switch Kn+1 , Main negative relay K 主负 One end is electrically connected.

[0019] Furthermore, the backup module M backup Both ends of the circuit are connected in parallel with the bidirectional DCDC.

[0020] Furthermore, the pre-charge circuit includes a main positive relay K 主正 , Pre-charge relay K 预充 and pre-charge resistor R 预充 , the main positive relay K 主正 One end of the pre-charge relay K 预充 , module M1, one end of switch K1 is electrically connected, pre-charge relay K 预充 The other end of the pre-charge resistor R 预充 One end is electrically connected to the pre-charge resistor R 预充 The other end is connected to the main positive relay K 主正 The other end is electrically connected.

[0021] Furthermore, the input end of the battery pack includes two high-voltage interfaces.

[0022] Furthermore, the two high-voltage interfaces are respectively a load interface and a charging interface, and the load interface is connected to the main positive relay K 主正 The charging interface is electrically connected to the charging relay K 充电 One end of the charging relay K 充电 The other end is connected to the main positive relay K 主正 , Pre-charge relay K 预充 , module M1, and one end of switch K1 are electrically connected.

[0023] Compared with the prior art, the present invention has the following beneficial effects: 1. Using a backup module loop can solve the problem of losing the entire pack after a single battery cell fails.

[0024] 2. Multiple battery packs (PACK) can share the same backup module circuit to maximize profits.

[0025] 3. The backup module circuit generally has a lower voltage (100V-200V). The backup module can be equipped with a small bidirectional DCDC device to back up the low-voltage power supply of the BMS, further increasing system safety while further reducing system deadweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] 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.

[0027] Figure 1 A circuit connection diagram of a high-safety aviation power battery system of the present invention;

[0028] Figure 2 A schematic diagram of the backup module circuit of the present invention designed outside the battery pack;

[0029] Figure 3 A schematic diagram of the backup module circuit design of the present invention inside the battery pack;

[0030] Figure 4 A circuit connection diagram of a single battery pack of the present invention;

[0031] Figure 5 The battery pack of the present invention includes a schematic diagram of two high-voltage interfaces. DETAILED DESCRIPTION

[0032] 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.

[0033] Embodiment 1: In some embodiments, please refer to the drawings of the specification Figure 1-Figure 5 , including at least one battery pack (PACK) and a backup module circuit;

[0034] like Figure 2 As shown, the backup module circuit can be designed outside the battery pack (PACK), such as Figure 3 As shown, the backup module circuit can also be designed inside the battery pack (PACK);

[0035] Under normal working conditions, the battery pack (PACK) is not connected to the backup module circuit;

[0036] When an abnormal operating condition occurs, the battery pack (PACK) is connected in series with the backup module circuit;

[0037] The battery pack (PACK) includes an electrical circuit and a pre-charging circuit;

[0038] One end of the electrical circuit is connected to the pre-charging circuit, and the other end of the electrical circuit is electrically connected to the backup module circuit;

[0039] The electrical circuit includes n modules, and the n modules are module M1, module M2, module M3...module M n-1 and module M n , the module M1, module M2, module M3...module M n-1 and module M n Connect in series one by one.

[0040] The electrical circuit includes n+1 switches, wherein the n+1 switches are switch K1, switch K2, switch K3, ..., switch K4. n-1 , switch K n and switch K n+1， The switch K1, switch K2, switch K3, ... switch K n-1 , switch K n and switch K n+1 The two ends of the module M1 are electrically connected to the switch K1 and the switch K2 respectively, and the two ends of the module M2 are electrically connected to the switch K2 and the switch K3 respectively. n The two ends of the switch K n , switch K n+1 Electrical connection.

[0041] The module M1, switch K1, and switch K2 form a first sub-packet, and the module M2, switch K2, and switch K3 form a second sub-packet. n , switch K n , switch K n+1 The nth sub-packet is formed, and the sub-packets are connected in series one by one.

[0042] When the aircraft high voltage architecture is a parallel architecture with multiple battery packs (PACK), this backup module circuit can be reused by multiple packs. For details, see Figure 1 , although attached Figure 1 Only two battery packs (PACK) are shown, but the same principle is applicable to multiple battery packs (PACK). The backup module is connected to the negative output circuit. When a module of the first battery pack (PACK) fails, refer to the explanation attached. Figure 1 The relay control logic of the battery pack (PACK) can be executed, and the rest of the battery packs (PACK) can operate according to normal conditions without switching relays.

[0043] The backup module circuit includes a backup module M backup And backup module dedicated relay K b .

[0044] Main negative relay K主负 Can be set in the battery pack (PACK), the main negative relay K 主负 It can also be set in the backup module loop.

[0045] The main negative relay K 主负 One end of the switch K n+1 、Module M n Electrical connection, main negative relay K 主负 The other end is connected to the backup module dedicated relay K b One end of the backup module is electrically connected to the dedicated relay K b The other end and the backup module M backup One end of the backup module M is electrically connected to backup The other end of the module M n , switch K n+1 , Main negative relay K 主负 One end is electrically connected.

[0046] like Figure 3 As shown, the backup module M backup The two ends of the two-way DCDC are connected in parallel with the two-way DCDC (DC-to-DC converter), which can turn the backup module into a redundant backup device for the low-voltage power supply of the BMS (BATTLEY MANAGEMENT SYSTEM). Since the DCDC is bidirectional, the backup power supply can also be supplemented when the main power supply of the BMS has surplus power, without having to worry about the problem of power shortage after the backup module supplies power to the BMS.

[0047] The role of the backup module is to bypass the sub-pack on the series circuit, which is equivalent to losing a sub-pack. Because the voltage of the high-voltage power load is within a certain range, if the number of modules in the battery pack is small, there is no backup module and a sub-pack is lost, there will be a voltage mismatch problem. If there is no backup module, it may cause excessive pressure difference between the battery packs, resulting in a large circulating current after landing.

[0048] The pre-charge circuit includes a main positive relay K 主正 , Pre-charge relay K 预充 and pre-charge resistor R 预充 , the main positive relay K 主正 One end of the pre-charge relay K 预充 , module M1, one end of switch K1 is electrically connected, pre-charge relay K 预充 The other end of the pre-charge resistor R 预充 One end is electrically connected to the pre-charge resistor R 预充 The other end is connected to the main positive relay K 主正 The other end is electrically connected.

[0049] When the battery system is powered on or off, the pre-charge relay K 预充 and pre-charge resistor R 预充 After the pre-charge is completed, the pre-charge relay K 预充 and pre-charge resistor R 预充 Disconnect the loop.

[0050] like Figure 5 As shown, the input end of the battery pack (PACK) includes two high-voltage interfaces.

[0051] The two high-voltage interfaces are the load interface and the charging interface.

[0052] The load interface is connected to the main positive relay K 主正 The charging interface is electrically connected to the charging relay K 充电 One end of the charging relay K 充电 The other end is connected to the main positive relay K 主正 , Pre-charge relay K 预充 , module M1, and one end of switch K1 are electrically connected.

[0053] When the battery system is operating normally, the main positive relay K 主正 , main negative relay K 主负 Closed, backup module dedicated relay K b And switch K1, switch K2... switch K n-1 and switch K n All disconnected, the circuit is formed by the main positive relay K 主正 , multiple modules, main negative relay K 主负 A circuit connected in series.

[0054] When the single cell where the module M1 is located experiences thermal runaway, the main positive relay K 主正 , backup module dedicated relay K b , switch K1 and switch K2 are closed, the main negative relay K 主负 And switch K3...switch K n-1 and switch K n All are disconnected, the circuit of the module where M1 is located is bypassed, and the circuit forms the main positive relay K 主正 , module M2...module Mn, backup module M backup , backup module dedicated relay K b Series circuit, backup module M backup Enter the series circuit to form a new sub-packet.

[0055] When the single cell where module M2 is located experiences thermal runaway, the main positive relay K 主正 , backup module dedicated relay K b , switch K2 and switch K3 are closed, the main negative relay K主负 And switch K1, switch K4...switch K n-1 and switch K n All are disconnected, the circuit of the module where M2 is located is bypassed, and the circuit forms the main positive relay K 主正 , module M1, module M3...module Mn, backup module M backup , backup module dedicated relay K b The backup module enters the series circuit to form a new sub-packet.

[0056] Similarly, when module M n-1 When thermal runaway occurs in the single cell, the main positive relay K 主正 , backup module dedicated relay K b , switch K n-1 and switch Kn is closed, the main negative relay K 主负 And switch K1, switch K2... switch K n-2 All disconnected, M n-1 The circuit of the module is bypassed, and the circuit forms the main positive relay K 主正 , module M1, module M2...module Mn, backup module M backup , backup module dedicated relay K b The backup module enters the series circuit to form a new sub-packet.

[0057] 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. A high-safety aviation power battery system, characterized by: Includes at least one battery pack and a backup module circuit; Under normal working conditions, the battery pack (PACK) is not connected to the backup module circuit; When an abnormal operating condition occurs, the battery pack (PACK) is connected in series with the backup module circuit; The battery pack includes an electrical circuit and a pre-charging circuit; One end of the electrical circuit is connected to the pre-charging circuit, and the other end of the electrical circuit is electrically connected to the backup module circuit.

2. The high-safety aviation power battery system according to claim 1, characterized in that: The electrical circuit includes n modules, wherein the n modules are module M1, module M2, module M3, ... module M n-1 and module M n , the module M1, module M2, module M3...module M n-1 and module M n Connect in series one by one.

3. The high-safety aviation power battery system according to claim 2, characterized in that: The electrical circuit includes n+1 switches, wherein the n+1 switches are switch K1, switch K2, switch K3, ..., switch K4. n-1 , switch K n and switch K n+1， The switch K1, switch K2, switch K3, ... switch K n-1 , switch K n and switch K n+1 The two ends of the module M1 are electrically connected to the switch K1 and the switch K2 respectively, and the two ends of the module M2 are electrically connected to the switch K2 and the switch K3 respectively. n The two ends of the switch K n , switch K n+1 Electrical connection.

4. The high-safety aviation power battery system according to claim 3, characterized in that: The backup module circuit includes a backup module M backup And backup module dedicated relay K b .

5. The high-safety aviation power battery system according to claim 4, characterized in that: Main negative relay K 主负 Set in the electrical circuit or backup module circuit.

6. The high-safety aviation power battery system according to claim 5, characterized in that: The main negative relay K 主负 One end of the switch K n+1 、Module M n Electrical connection, main negative relay K 主负 The other end is connected to the backup module dedicated relay K b One end of the backup module is electrically connected to the dedicated relay K b The other end and the backup module M backup One end of the backup module M is electrically connected to backup The other end of the module M n , switch K n+1 , Main negative relay K 主负 One end is electrically connected.

7. The high-safety aviation power battery system according to claim 6, characterized in that: The backup module M backup Both ends of the circuit are connected in parallel with the bidirectional DCDC.

8. The high-safety aviation power battery system according to claim 7, characterized in that: The pre-charging circuit includes a main positive relay K 主正 , Pre-charge relay K 预充 and pre-charge resistor R 预充 , the main positive relay K 主正 One end of the pre-charge relay K 预充 , module M1, one end of switch K1 is electrically connected, pre-charge relay K 预充 The other end of the pre-charge resistor R 预充 One end is electrically connected to the pre-charge resistor R 预充 The other end is connected to the main positive relay K 主正 The other end is electrically connected.

9. The high-safety aviation power battery system according to claim 8, characterized in that: The input end of the battery pack includes two high-voltage interfaces.

10. The high-safety aviation power battery system according to claim 9, characterized in that: The two high-voltage interfaces are load interface and charging interface. The load interface is connected to the main positive relay K 主正 The charging interface is electrically connected to the charging relay K 充电 One end of the charging relay K 充电 The other end is connected to the main positive relay K 主正 , Pre-charge relay K 预充 , module M1, and one end of switch K1 are electrically connected.

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