Aviation power battery system with excellent voltage consistency

Abstract

The invention discloses an aviation power battery system with excellent voltage consistency, and belongs to the technical field of battery management systems, the aviation power battery system comprises at least one charger and a plurality of battery modules, and each battery module is electrically connected with a group of current conversion phase locking assemblies; the plurality of current conversion phase locking assemblies are electrically connected with a power distribution unit; the power distribution unit is electrically connected with a plurality of aircraft driving assemblies; the current conversion phase locking assembly is used for converting direct current of the battery module into three-phase alternating current and locking the phase of the three-phase alternating current; the power supply distribution unit is used for carrying out parallel convergence on multiple groups of phase-locked three-phase alternating current and supplying power to multiple groups of aircraft driving components; the output end of the aircraft driving assembly is connected with a rotor wing. By means of the mode, the circulating current generated by parallel connection of multiple bags is eliminated.

Description

Technical Field

[0001] The present invention relates to the technical field of battery management systems, and in particular to an aviation power battery system with excellent voltage consistency. Background Art

[0002] In the field of aircraft, for safety reasons, redundant backup of the core power battery is performed to meet the reliability requirements of the entire power system. Generally, 3 to 10 sub-packs form a power system, and the aircraft can still land safely if one of the sub-packs is lost.

[0003] A more common integration method is to connect multiple battery packs in parallel on the bus bar of the same PDU (power distribution unit). All motors and other high-voltage electrical devices draw power from this PDU. The advantage of this architecture is that it can ensure the consistency of the battery pack charging and discharging process as much as possible, and the failure of any sub-pack will not affect the power consumption of other high-voltage devices, nor will it affect the flight attitude of the aircraft. This is the most widely used architectural solution in the industry, which greatly improves and ensures the safety and reliability of the aircraft's power system.

[0004] However, compared to electric vehicles that only have one battery pack, the parallel connection of multiple packs has the problem of circulation between packs, which poses a potential safety risk.

[0005] Defects and shortcomings of the existing technology:

[0006] One of the biggest drawbacks of connecting multiple packages in parallel is that there will be circulation. The characteristics of circulation are:

[0007] ① Spontaneous generation: When the battery pack is in a high voltage state and both packs are in a static state, the battery pack with a higher total voltage in the parallel circuit will spontaneously charge the battery pack with a lower voltage to achieve voltage balance in the parallel circuit;

[0008] ②Direct current: The output and input of the battery pack are both direct current;

[0009] ③ Uncontrollable: BMS cannot control the size of the circulating current and can only block the circulating current by controlling the power-off of the battery pack, but this is of little significance because many power usage scenarios do not allow the battery pack to be easily powered off. At the same time, the voltage difference is still not eliminated when it is powered on again after powering off, and the circulating current will continue to be generated. Based on this, the present invention designs an aviation power battery system with excellent voltage consistency to solve the above problems.

[0010] The existing technology in the industry is "multiple battery packs are connected in parallel on the bus bar of the same PDU (power distribution unit), and all motors and other high-voltage electrical devices draw power from this PDU." This solution will cause circulating current problems, and most manufacturers have not designed solutions specifically for this risk.

[0011] The energy storage industry has tried to add unidirectional high-voltage switching current diodes to limit the circulating current, but this will create new problems: high-voltage switching current diodes with excessive current are difficult to select, and additional heat sources are introduced into the battery pack, increasing battery safety risks; and this solution can only limit the circulating current to a certain extent and cannot completely solve the circulating current.

[0012] Based on this, the present invention designs an aviation power battery system with excellent voltage consistency to solve the above problems. Summary of the invention

[0013] In view of the above-mentioned shortcomings of the prior art, the present invention provides an aviation power battery system with excellent voltage consistency.

[0014] To achieve the above objectives, the present invention is implemented through the following technical solutions:

[0015] An aviation power battery system with excellent voltage consistency includes at least one charger and a plurality of battery modules, each battery module being electrically connected to a set of current conversion phase locking components;

[0016] A plurality of the current conversion phase locking components are electrically connected to a power distribution unit;

[0017] The power distribution unit is electrically connected to a plurality of aircraft drive components;

[0018] The current conversion phase locking component is used to convert the direct current of the battery module into three-phase alternating current and lock the phase of the three-phase alternating current;

[0019] The power distribution unit connects multiple sets of phase-locked three-phase alternating currents in parallel and supplies power to multiple sets of aircraft drive components;

[0020] The output end of the aircraft drive assembly is connected to a rotor;

[0021] The battery module includes a plurality of batteries, a fuse 1, a charging relay, a main relay 1, a pre-charging circuit and a main relay 2;

[0022] The multiple batteries are connected in series to form a battery pack, the positive electrode of the battery pack is electrically connected to one end of the fuse 1, the negative electrode of the battery pack is electrically connected to one end of the main relay 2, the other end of the main relay 2 is electrically connected to the negative electrode of the charger and the DC / AC converter, and the other end of the fuse 1 is electrically connected to one end of the charging relay and the main relay 1;

[0023] The other end of the charging relay is electrically connected to the positive electrode of the charger;

[0024] The other end of the main relay 1 is electrically connected to the positive input terminal of the DC / AC converter;

[0025] The pre-charging circuit is connected in parallel with two ends of the main relay.

[0026] Furthermore, the pre-charging circuit includes a pre-charging relay and a pre-charging resistor, the pre-charging relay and the pre-charging resistor are connected in series, the pre-charging resistor is electrically connected to one end of the main relay, and the pre-charging relay is electrically connected to the other end of the main relay.

[0027] Furthermore, the current conversion phase locking component includes a DC-AC converter and a phase locking loop;

[0028] The input end of the DC-AC converter is electrically connected to the battery module, the output end of the DC-AC converter is electrically connected to the input end of the phase-locked loop, and the output end of the phase-locked loop is electrically connected to the power distribution unit.

[0029] Furthermore, the DC-AC converter is used to convert the DC power of the battery module into three-phase AC power.

[0030] Furthermore, the phase-locked loop is used to lock the phase of the three-phase alternating current.

[0031] Furthermore, the power distribution unit includes a power distribution box and a plurality of fuses 2;

[0032] The distribution box is electrically connected to the phase-locked loop, one end of the second fuse is electrically connected to the live bus bar of the distribution box, the other end of the second fuse is electrically connected to the aircraft drive assembly, and the distribution box is electrically connected to the aircraft drive assembly.

[0033] Furthermore, the aircraft drive assembly includes a motor and an AC converter, the live wire at the input end of the AC converter is electrically connected to the other end of the second fuse, and the neutral wire and the ground wire at the input end of the AC converter are electrically connected to the neutral wire bus bar and the ground wire bus bar of the distribution box respectively;

[0034] The AC converter is used to convert the three-phase AC power of the distribution box into a three-phase AC power suitable for the motor.

[0035] Furthermore, the output end of the motor is fixedly connected to a rotor.

[0036] Furthermore, the DC-AC converter is a DCAC inverter.

[0037] Furthermore, the AC converter is an ACAC circuit.

[0038] Compared with the prior art, the present invention has the following beneficial effects: 1. Losing a battery module does not affect the safety of the aircraft;

[0039] The problem of circulating current between packs is completely solved by adding DCAC devices before the battery packs are connected in parallel. Since DCAC is unidirectional and converts AC into DC, the generation of circulating current between packs is completely blocked.

[0040] At the same time, in order to solve the problem of phase difference after AC power convergence, a phase-locked loop is added to the solution to ensure that the AC power will not undergo phase cancellation.

[0041] 2. Compared with the prior art, the advantage of this solution is that it can completely solve the circulation problem. Since the battery module is direct current, multiple battery modules can only generate circulation after being connected in parallel through a power distribution unit. This solution sets a DC-AC converter and a phase-locked loop between the battery module and the power distribution unit, so that the original circuit becomes half direct current and half alternating current, thereby eliminating the generation of circulation current. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] 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.

[0043] Figure 1 A frame of an aviation power battery system with excellent voltage consistency according to the present invention Figure 1 ;

[0044] Figure 2 A frame of an aviation power battery system with excellent voltage consistency according to the present invention Figure 2 ;

[0045] Figure 3 A circuit diagram of a power distribution unit of the present invention;

[0046] Figure 4 It is a schematic diagram of the aircraft drive assembly and rotor of the present invention;

[0047] Figure 5 It is a circuit diagram of the battery module of the present invention.

[0048] The numbers in the figure represent:

[0049] 1. Charger; 2. Battery module; 21. Battery; 22. Fuse 1; 23. Charging relay; 24. Main relay 1; 25. Pre-charge relay; 26. Pre-charge resistor; 27. Main relay 2; 3. DC-AC converter; 4. Phase-locked loop; 5. Power distribution unit; 51. Distribution box; 52. Fuse 2; 6. Aircraft drive assembly; 61. Motor; 62. AC converter; 7. Rotor. DETAILED DESCRIPTION

[0050] 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.

[0051] Embodiment 1: In some embodiments, please refer to the drawings of the specification Figure 1-Figure 5 , an aviation power battery system with excellent voltage consistency, comprising at least one charger 1 and a plurality of battery modules 2;

[0052] Each battery module 2 is electrically connected to a set of current conversion phase locking components;

[0053] The multiple current conversion phase locking components are electrically connected to a power distribution unit 5;

[0054] The power distribution unit 5 is electrically connected to a plurality of aircraft drive components;

[0055] The current conversion phase locking component is used to convert the direct current of the battery module 2 into three-phase alternating current and lock the phase of the three-phase alternating current;

[0056] The power distribution unit connects multiple sets of phase-locked three-phase alternating currents in parallel and supplies power to multiple sets of aircraft drive components 6;

[0057] The output end of the aircraft drive assembly 6 is connected to the rotor 7;

[0058] The battery module 2 includes a plurality of batteries 21, a fuse 1 22, a charging relay 23, a main relay 1 24, a pre-charging circuit and a main relay 27;

[0059] A plurality of batteries 21 are connected in series to form a battery pack, the positive electrode of the battery pack is electrically connected to one end of a fuse 22, the negative electrode of the battery pack is electrically connected to one end of a main relay 27, the other end of the main relay 27 is electrically connected to the negative electrode of the charger 1 and the DC / AC converter 3, and the other end of the fuse 22 is electrically connected to one end of the charging relay 23 and the main relay 24;

[0060] The other end of the charging relay 23 is electrically connected to the positive electrode of the charger 1;

[0061] The other end of the main relay 24 is electrically connected to the positive input terminal of the DC-AC converter 3;

[0062] The pre-charging circuit is connected in parallel with both ends of the main relay 24.

[0063] The pre-charging circuit includes a pre-charging relay 25 and a pre-charging resistor 26. The pre-charging relay 25 is connected in series with the pre-charging resistor 26. The pre-charging resistor 26 is electrically connected to one end of the main relay 24, and the pre-charging relay 25 is electrically connected to the other end of the main relay 24.

[0064] The battery module 2 contains multiple batteries 21 connected in series. The battery 21 is a series-parallel combination of battery cells. The total negative circuit of the series-connected batteries 21 is connected to the total negative circuit of the battery module 2 via the main relay 27. The total negative circuit of the battery module 2 is divided into two in terms of electrical connection, namely the total negative circuit for charging and the total negative circuit for discharging of the battery module 2; the total positive circuit of the battery 21 is connected to the total positive circuit for charging of the battery pack via a fuse 22 and a charging relay 23, and the total positive circuit of the battery 21 is connected to the total positive circuit for discharging of the battery module 2 via a main relay 24. At the same time, a pre-charging circuit is connected in parallel to the discharge circuit of the main relay 24 to charge the capacitor of the motor 61 and prevent large currents from impacting electrical components in the power circuit.

[0065] Fuse 1 22 is used to cut off the faulty battery module 2 from the power supply circuit when a single battery module 2 is short-circuited. Charging relay 23, main relay 1 24, pre-charging relay 25, and main relay 2 27 are used to control the high voltage power on and off during the charging and discharging process.

[0066] The current conversion phase locking component includes a DC-AC converter 3 and a phase locking loop 4;

[0067] The input end of the DC-AC converter 3 is electrically connected to the battery module 2 , the output end of the DC-AC converter 3 is electrically connected to the input end of the phase-locked loop 4 , and the output end of the phase-locked loop 4 is electrically connected to the power distribution unit 5 .

[0068] Phase locked loop 4 is referred to as PLL;

[0069] The DC-AC converter 3 is used to convert the DC power of the battery module 2 into three-phase AC power;

[0070] The phase-locked loop 4 is used to lock the phase of the three-phase alternating current.

[0071] When the present invention is used, the loss of one battery module 2 does not affect the safety of the aircraft;

[0072] The problem of circulating current between packs is completely solved by adding DCAC devices before the battery packs are connected in parallel. Since DCAC is unidirectional and converts AC into DC, the generation of circulating current between packs is completely blocked.

[0073] At the same time, in order to solve the problem of phase difference after AC power convergence, a phase locking loop 4 is added to the solution to ensure that the AC power will not be phase-cancelled.

[0074] Compared with the prior art, the advantage of this solution is that it can completely solve the circulation problem. Since the battery module 2 is direct current, multiple battery modules 2 can only generate circulation after being connected in parallel through the power distribution unit 5. This solution sets a DC-AC converter 3 and a phase-locked loop 4 between the battery module 2 and the power distribution unit 5, so that the original circuit becomes half direct current and half alternating current, thereby eliminating the generation of circulation and ensuring voltage consistency.

[0075] The power distribution unit 5 includes a distribution box 51 and a plurality of fuses 52;

[0076] The power distribution box 51 is electrically connected to the phase-locked loop 4, one end of the second fuse 52 is electrically connected to the live bus bar of the power distribution box 51, the other end of the second fuse 52 is electrically connected to the aircraft drive assembly, and the power distribution box 51 is electrically connected to the aircraft drive assembly 6;

[0077] In the high voltage architecture of the present invention, there are multiple battery modules 2 to power the motor 61, and the aircraft drive assembly 6 drives the rotor 7 to rotate to generate lift, thereby supporting the aircraft's takeoff, cruising, landing and other working conditions. Each battery module 2 has an independent charging port attached Figure 1 , or multiple battery modules 2 can share one charging interface Figure 2 The direct current output by the battery module 2 is converted into alternating current after passing through the current conversion phase locking component DC→AC. The alternating current is three-phase electricity. At the same time, the current conversion phase locking component performs phase locking. All alternating currents are connected in parallel on the power distribution unit 5 and output to multiple aircraft drive components 6 for use.

[0078] The function of the second fuse 52 is to cut off the faulty distribution box 51 from the power supply circuit when a single distribution box 51 is short-circuited, so as to avoid damage to the entire high-voltage circuit.

[0079] The aircraft drive assembly 6 includes a motor 61 and an AC converter 62. The live wire at the input end of the AC converter 62 is electrically connected to the other end of the fuse 2 52. The neutral wire and the ground wire at the input end of the AC converter 62 are electrically connected to the neutral bus bar and the ground bus bar of the distribution box 51 respectively.

[0080] The AC converter 62 is used to convert the three-phase AC power of the distribution box 51 into a three-phase AC power compatible with the motor 61;

[0081] The output end of the motor 61 is fixedly connected to the rotor 7 .

[0082] The DC-AC converter 3 is a DCAC inverter.

[0083] The AC converter 62 is an ACAC circuit.

[0084] 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 aviation power battery system with excellent voltage consistency, comprising at least one charger (1) and a plurality of battery modules (2), characterized in that: Each battery module (2) is electrically connected to a set of current conversion phase locking components; The plurality of current conversion phase locking components are electrically connected to a power distribution unit (5); The power distribution unit (5) is electrically connected to a plurality of aircraft drive components; The current conversion phase locking component is used to convert the direct current of the battery module (2) into three-phase alternating current and to lock the phase of the three-phase alternating current; The power distribution unit connects multiple sets of phase-locked three-phase alternating currents in parallel and supplies power to multiple sets of aircraft drive components (6); The output end of the aircraft driving assembly (6) is connected to a rotor (7); The battery module (2) comprises a plurality of batteries (21), a fuse 1 (22), a charging relay (23), a main relay 1 (24), a pre-charging circuit and a main relay 2 (27); The multiple batteries (21) are connected in series to form a battery pack, the positive electrode of the battery pack is electrically connected to one end of a fuse (22), the negative electrode of the battery pack is electrically connected to one end of a main relay (27), the other end of the main relay (27) is electrically connected to the negative electrode of the charger (1) and the DC / AC converter (3), and the other end of the fuse (22) is electrically connected to one end of the charging relay (23) and the main relay (24); The other end of the charging relay (23) is electrically connected to the positive electrode of the charger (1); The other end of the main relay 1 (24) is electrically connected to the positive input terminal of the DC-AC converter (3); The pre-charging circuit is connected in parallel with both ends of the main relay 1 (24).

2. The aviation power battery system with excellent voltage consistency according to claim 1, characterized in that: The pre-charging circuit comprises a pre-charging relay (25) and a pre-charging resistor (26), the pre-charging relay (25) and the pre-charging resistor (26) being connected in series, the pre-charging resistor (26) being electrically connected to one end of a main relay (24), and the pre-charging relay (25) being electrically connected to the other end of the main relay (24).

3. The aviation power battery system with excellent voltage consistency according to claim 2, characterized in that: The current conversion phase locking component comprises a DC-AC converter (3) and a phase locking loop (4); The input end of the DC-AC converter (3) is electrically connected to the battery module (2), the output end of the DC-AC converter (3) is electrically connected to the input end of the phase-locked loop (4), and the output end of the phase-locked loop (4) is electrically connected to the power distribution unit (5).

4. The aviation power battery system with excellent voltage consistency according to claim 3, characterized in that: The DC-AC converter (3) is used to convert the DC power of the battery module (2) into three-phase AC power.

5. The aviation power battery system with excellent voltage consistency according to claim 4, characterized in that: The phase-locked loop (4) is used to lock the phase of three-phase alternating current.

6. The aviation power battery system with excellent voltage consistency according to claim 5, characterized in that: The power distribution unit (5) comprises a distribution box (51) and a plurality of fuses (52); The distribution box (51) is electrically connected to the phase-locked loop (4), one end of the second fuse (52) is electrically connected to the live bus bar of the distribution box (51), the other end of the second fuse (52) is electrically connected to the aircraft drive assembly (6), and the distribution box (51) is electrically connected to the aircraft drive assembly (6).

7. The aviation power battery system with excellent voltage consistency according to claim 6, characterized in that: The aircraft drive assembly (6) comprises a motor (61) and an AC converter (62), wherein the live wire at the input end of the AC converter (62) is electrically connected to the other end of the second fuse (52), and the neutral wire and the ground wire at the input end of the AC converter (62) are electrically connected to the neutral wire bus bar and the ground wire bus bar of the distribution box (51) respectively; The AC converter (62) is used to convert the three-phase AC power of the distribution box (51) into a three-phase AC power that is compatible with the motor (61).

8. The aviation power battery system with excellent voltage consistency according to claim 7, characterized in that: The output end of the motor (61) is fixedly connected to a rotor (7).

9. The aviation power battery system with excellent voltage consistency according to claim 8, characterized in that: The DC-AC converter (3) is a DCAC inverter.

10. The aviation power battery system with excellent voltage consistency according to claim 9, characterized in that: The AC converter (62) is an ACAC circuit.

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