Airborne high-voltage battery parallel power supply and distribution system and control method

Abstract

The invention relates to the field of eVTOL battery systems, and provides an airborne high-voltage battery parallel power supply and distribution system and a control method in order to reduce the use cost and the space volume of airborne high-voltage battery parallel power supply and distribution. According to the method, charging control and power distribution are integrated on the same equipment by means of general equipment for charging the electric vehicle, a high-voltage power distribution controller is adopted to control charging and power distribution of a plurality of groups of high-voltage batteries, and a charging grid-connected strategy and a power supply grid-connected strategy of the plurality of groups of high-voltage batteries are determined; cost, space volume occupation and weight are reduced, redundant design of power supply and power distribution is realized, and reliability of a power supply and distribution system is improved.

Description

Technical Field

[0001] The present invention relates to the field of eVTOL battery systems, and specifically to an airborne high-voltage battery parallel power supply and distribution system and a control method therefor. Background Art

[0002] An electric vertical take-off and landing aircraft (eVTOL) has great application prospects in the field of urban air transportation as a greener and safer aircraft. It usually adopts a multi-rotor design, mainly aiming at the future low-altitude economy direction, realizing manned transportation that upgrades from a civilian electric vehicle to the air domain, and is expected to achieve air transportation of personnel and materials in the future, which conforms to the low-altitude economy policy direction that the country will vigorously develop in the future and has obtained great development in recent years.

[0003] In order to meet the requirements of environmental protection and economy, new energy is usually used as the power for eVTOL. As an aircraft that needs to take off and land vertically and fly long distances, the general requirements for the power battery pack are high discharge rate and large stored energy. Therefore, the weight and volume of the power battery pack account for a relatively large proportion in the aircraft. Usually, a single power battery pack cannot meet the internal installation space requirements of eVTOL, and it is necessary to divide the energy of the power battery pack into multiple units and supply power to the motors of multiple rotors through a power distribution system to achieve a redundant design of power supply and distribution and improve the reliability of the power supply and distribution system.

[0004] The existing airborne power supply and distribution system mainly uses low voltage for power supply and distribution. Energy storage, charging control, and power distribution are carried out by different airborne devices respectively. The cross-linking between the various airborne devices is complex, and the use cost is high, and the space volume occupied and the weight are large. Summary of the Invention

[0005] In order to reduce the use cost and space volume of airborne high-voltage battery parallel power supply and distribution, the present application provides an airborne high-voltage battery parallel power supply and distribution system and a control method therefor.

[0006] The technical solution adopted by the present invention to solve the above problems is as follows:

[0007] An airborne high-voltage battery parallel power supply and distribution system, comprising: a high-voltage power distribution controller and at least two high-voltage lithium-ion battery systems. The high-voltage power distribution controller includes a control system, a high-voltage busbar, a communication and power input connector, and at least one output unit for connecting a load. The communication and power input connector is used to connect each high-voltage lithium-ion battery system and external devices;

[0008] When the external device is a charging power source: The high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected charging strategy, and sends a charging instruction to the charging power source to start charging and charging protection.

[0009] When the external device is an electrical integrated management center: The high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected power supply strategy based on the power supply requirements of the electrical integrated management center, and closes the output unit as required.

[0010] Further, the high-voltage lithium-ion battery system includes a high-voltage battery pack, a power management system, a positive terminal contactor, and a negative terminal contactor. The power management system is connected to the control system through communication and a power input connector. The high-voltage lithium-ion battery system is connected to the high-voltage busbar by closing the positive terminal contactor and the negative terminal contactor.

[0011] Further, it also includes a vehicle socket. When the external device is an electric vehicle charging pile, the high-voltage power distribution controller is connected to the electric vehicle charging pile through the vehicle socket.

[0012] The on-board high-voltage battery parallel power supply and distribution control method is applied to the on-board high-voltage battery parallel power supply and distribution system, and includes:

[0013] Step 1: Determine the working state of the on-board high-voltage battery parallel power supply and distribution system, and the working state is the charging state or the power supply state;

[0014] Step 2: Perform insulation detection on all high-voltage lithium-ion battery systems;

[0015] Step 3: If the working state of the on-board high-voltage battery parallel power supply and distribution system is the charging state, then: The high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected charging strategy, and sends a charging instruction to the charging power source to start charging and charging protection;

[0016] If the working state of the on-board high-voltage battery parallel power supply and distribution system is the power supply state, then: The high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected power supply strategy based on the power supply requirements of the electrical integrated management center, and closes the output unit as required.

[0017] Further, the method for determining the working state of the on-board high-voltage battery parallel power supply and distribution system is: If the high-voltage power distribution controller is connected to the charging power source, it is in the charging state; if the high-voltage power distribution controller is connected to the electrical integrated management center, it is in the power supply state.

[0018] Further, the steps of insulation detection are:

[0019] The high-voltage power distribution controller sends an instruction to close the positive terminal contactor and the negative terminal contactor of the a-th high-voltage lithium-ion battery system;

[0020] The positive terminal contactor and negative terminal contactor of the a-th high-voltage lithium-ion battery system are closed;

[0021] After the high-voltage power distribution controller performs insulation detection, it sends an instruction to disconnect the positive terminal contactor and negative terminal contactor of the a-th high-voltage lithium-ion battery system; the a-th high-voltage lithium-ion battery system disconnects the positive terminal contactor and negative terminal contactor;

[0022] The above process is carried out in sequence until the insulation detection of all high-voltage lithium-ion battery systems is completed.

[0023] Furthermore, the grid-connected charging strategy means:

[0024] The high-voltage lithium-ion battery systems send charging requests to the high-voltage power distribution controller respectively according to their own states;

[0025] The high-voltage power distribution controller calculates the maximum voltage difference between the high-voltage lithium-ion battery systems according to the voltage data of each high-voltage lithium-ion battery system;

[0026] If the maximum voltage difference < X% of the full charge voltage of the high-voltage lithium-ion battery system, then directly close the positive terminal contactor and negative terminal contactor of each high-voltage lithium-ion battery system, and make them connected in parallel to the high-voltage busbar of the high-voltage power distribution controller;

[0027] If the maximum voltage difference ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, then first connect the high-voltage lithium-ion battery system with the lowest total voltage to the high-voltage busbar of the high-voltage power distribution controller, and charge it with a YCA current until the voltage difference between it and the second lowest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system; carry out in sequence until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller;

[0028] After all high-voltage lithium-ion battery systems are connected in parallel, use the minimum current value in each charging request as the total charging current and the highest requested voltage as the total charging voltage, and send a charging instruction to the electric vehicle charging pile to start charging until the current values in the charging requests of all high-voltage lithium-ion battery systems are the same; then use the sum of the currents in each charging request as the total charging current and the highest requested voltage as the total charging voltage, and send a charging instruction to the electric vehicle charging pile to start charging; stop charging when the voltage of any one high-voltage lithium-ion battery system reaches the highest requested voltage, and the high-voltage power distribution controller controls to disconnect the positive terminal contactor and negative terminal contactor in all high-voltage lithium-ion battery systems.

[0029] Furthermore, the charging request is fast charging, large current charging or small current charging.

[0030] Further, X is 0.65, Y and Z are both 0.1, and the currents for fast charging, large current charging, and small current charging respectively correspond to 0.5C, 0.2C, and 0.1C of the battery pack capacity.

[0031] Further, the grid-connected power supply strategy means that:

[0032] The high-voltage distribution controller calculates the maximum voltage difference between each high-voltage lithium-ion battery system based on the voltage data of each high-voltage lithium-ion battery system;

[0033] If the maximum voltage difference < X% of the full charge voltage of the high-voltage lithium-ion battery system, directly close the positive terminal contactor and negative terminal contactor of each high-voltage lithium-ion battery system to make them parallel on the high-voltage busbar of the high-voltage distribution controller;

[0034] If the maximum voltage difference ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, first connect the high-voltage lithium-ion battery system with the highest total voltage to the high-voltage busbar of the high-voltage distribution controller, then close the required output unit, and discharge until the voltage difference between the high-voltage lithium-ion battery system with the highest total voltage and the high-voltage lithium-ion battery system with the second highest total voltage is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system, and connect the high-voltage lithium-ion battery system with the second highest total voltage in parallel on the high-voltage busbar of the high-voltage distribution controller; and so on until all high-voltage lithium-ion battery systems are connected in parallel on the high-voltage busbar of the high-voltage distribution controller.

[0035] The beneficial effects of the present invention compared with the prior art are as follows: The charging control, high-voltage battery charging protection, power distribution output, and parallel control of multiple groups of high-voltage batteries are comprehensively integrated and designed. By borrowing the general equipment for electric vehicle charging, the charging control and power distribution are integrated in the same device. The high-voltage distribution controller is used to control the charging and power distribution of multiple groups of high-voltage batteries, and the charging grid-connection strategy and power supply grid-connection strategy for multiple groups of high-voltage batteries are determined; the cost, space volume occupation, and weight are reduced, the redundant design of power supply and power distribution is realized, and the reliability of the power supply and distribution system is improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 It is the architecture diagram of the airborne high-voltage battery parallel power supply and distribution system. DETAILED DESCRIPTION OF THE INVENTION

[0037] In order to make the objectives, technical solutions, and advantages of the present invention clearer and more understandable, the following further describes the present invention in detail with reference to the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0038] Airborne high-voltage battery parallel power supply and distribution system, comprising: a high-voltage power distribution controller and at least two high-voltage lithium-ion battery systems. The high-voltage power distribution controller includes a control system, a high-voltage busbar, a communication and power input connector, and at least one output unit for connecting a load. The communication and power input connector is used to connect each high-voltage lithium-ion battery system and external devices; the high-voltage lithium-ion battery system includes a high-voltage battery pack, a power management system, a positive terminal contactor, and a negative terminal contactor. The power management system is connected to the control system through the communication and power input connector, and the high-voltage lithium-ion battery system is connected to the high-voltage busbar by closing the positive terminal contactor and the negative terminal contactor;

[0039] When the external device is a charging power source: the high-voltage power distribution controller controls the high-voltage lithium-ion battery systems to be connected in parallel to the high-voltage busbar according to the grid-connected charging strategy, and sends a charging instruction to the charging power source to start charging and charging protection;

[0040] When the external device is an electrical integrated management center: the high-voltage power distribution controller controls the high-voltage lithium-ion battery systems to be connected in parallel to the high-voltage busbar according to the grid-connected power supply strategy according to the power supply requirements of the electrical integrated management center, and closes the output unit as required.

[0041] Specifically, the output unit includes an output main contactor, a soft start contactor, and a soft start resistor. The soft start contactor and the soft start resistor are connected in series and then connected in parallel with the output main contactor.

[0042] Furthermore, it also includes a vehicle socket. When the external device is an electric vehicle charging pile, the high-voltage power distribution controller is connected to the electric vehicle charging pile through the vehicle socket.

[0043] Correspondingly, the present invention also provides an airborne high-voltage battery parallel power supply and distribution control method, which is applied to the airborne high-voltage battery parallel power supply and distribution system, including:

[0044] Step 1: Determine the working state of the airborne high-voltage battery parallel power supply and distribution system. The working state is a charging state or a power supply state; if the high-voltage power distribution controller is connected to a charging power source, it is in a charging state, and if the high-voltage power distribution controller is connected to an electrical integrated management center, it is in a power supply state.

[0045] Step 2: Perform insulation detection on all high-voltage lithium-ion battery systems. The steps of insulation detection are:

[0046] The high-voltage power distribution controller sends an instruction to close the positive terminal contactor and the negative terminal contactor of the a-th high-voltage lithium-ion battery system;

[0047] The a-th high-voltage lithium-ion battery system closes the positive terminal contactor and the negative terminal contactor;

[0048] After the high-voltage power distribution controller performs insulation detection, it sends an instruction to disconnect the positive and negative contactors of the a-th high-voltage lithium-ion battery system; the a-th high-voltage lithium-ion battery system disconnects the positive and negative contactors.

[0049] The above process is carried out in sequence until all high-voltage lithium-ion battery systems complete insulation detection.

[0050] Insulation detection can effectively prevent accidents such as short circuits, electric shocks, and fires caused by insulation failure of electrical equipment, thus ensuring the safety of personnel and equipment, facilitating the timely discovery and handling of insulation problems, ensuring that electrical equipment maintains good insulation during operation, reducing equipment failure rates, and improving system reliability.

[0051] Step 3: If the working state of the airborne high-voltage battery parallel power supply and distribution system is the charging state, then: the high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected charging strategy, and sends a charging instruction to the charging power supply to start charging and charging protection.

[0052] If the working state of the airborne high-voltage battery parallel power supply and distribution system is the power supply state, then: the high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage busbar according to the grid-connected power supply strategy according to the power supply requirements of the electrical integrated management center, and closes the output unit as required.

[0053] Specifically, the grid-connected charging strategy means:

[0054] The high-voltage lithium-ion battery system sends charging requests to the high-voltage power distribution controller respectively according to its own state;

[0055] The high-voltage power distribution controller calculates the maximum voltage difference between the high-voltage lithium-ion battery systems based on the voltage data of each high-voltage lithium-ion battery system.

[0056] If the maximum voltage difference < X% of the full charge voltage of the high-voltage lithium-ion battery system, then directly close the positive and negative contactors of each high-voltage lithium-ion battery system to make it connected in parallel to the high-voltage busbar of the high-voltage power distribution controller.

[0057] If the maximum pressure difference ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, first connect the high-voltage lithium-ion battery system with the lowest total voltage to the high-voltage busbar of the high-voltage power distribution controller and charge it with a current of YCA until the voltage difference between it and the second lowest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system; then connect the second lowest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; charge it with a current of YCA until the voltage difference between it and the third lowest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system, and then connect the third lowest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; and so on until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller.

[0058] After all high-voltage lithium-ion battery systems are connected in parallel, use the minimum value of the currents in each charging request as the total charging current and the highest requested voltage as the total charging voltage, and send a charging command to the electric vehicle charging pile to start charging until the current values in the charging requests of all high-voltage lithium-ion battery systems are the same; then use the sum of the currents in each charging request as the total charging current and the highest requested voltage as the total charging voltage, and send a charging command to the electric vehicle charging pile to start charging; stop charging when the voltage of any high-voltage lithium-ion battery system reaches the highest requested voltage, and the high-voltage power distribution controller controls to disconnect the positive contactor and negative contactor in all high-voltage lithium-ion battery systems.

[0059] The grid-connected power supply strategy means:

[0060] The high-voltage power distribution controller calculates the maximum pressure difference between each high-voltage lithium-ion battery system based on the voltage data of each high-voltage lithium-ion battery system.

[0061] If the maximum pressure difference < X% of the full charge voltage of the high-voltage lithium-ion battery system, directly close the positive contactor and negative contactor of each high-voltage lithium-ion battery system to connect them in parallel to the high-voltage busbar of the high-voltage power distribution controller.

[0062] If the maximum pressure difference ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, first connect the high-voltage lithium-ion battery system with the highest total voltage to the high-voltage busbar of the high-voltage power distribution controller, then close the required output unit, and discharge until the voltage difference between the high-voltage lithium-ion battery system with the highest total voltage and the second highest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system, and connect the second highest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; discharge until the voltage difference from the third highest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system, and connect the third highest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; and so on until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller.

[0063] It should be noted that in the present invention, the so-called low voltage generally refers to below 29V, and the high voltage refers to above 205V, and the highest can reach 806V.

[0064] As Figure 1 shown, the airborne high-voltage battery parallel power supply and distribution system provided in this embodiment includes 4 high-voltage lithium-ion battery systems and 1 high-voltage power distribution controller. Among them, the high-voltage lithium-ion battery system is composed of 192 lithium-ion batteries, 96 temperature sensors, 1 set of power management system, 1 positive terminal contactor, 1 negative terminal contactor, liquid cooling components, connection components, insulating materials, etc. The rated capacity of the high-voltage lithium-ion battery system is 43Ah, with 7C continuous and 10C pulse discharge capabilities, storing 30KWh of energy, with a working temperature range of -40°C to 60°C and a working voltage range of 480V to 806V.

[0065] The high-voltage power distribution controller is composed of 1 set of control system, 8 main contactors, 8 soft-start contactors, 8 soft-start resistors, 1 set of high-voltage busbar, 8 input connection ports for high-voltage lithium-ion battery systems, 16 output connection ports for motor power supply, 1 communication and power input connector, fuse, etc. It has the function of short-circuit protection for the output power distribution line, with a working voltage range of 480VDC to 850VDC, a voltage detection accuracy of ±1%, a maximum continuous current of 550A at the input end, and a maximum current of 260A at the output end. Among them, the communication and power input connector is used to connect the control system with the power management system and the charging power supply, or to connect the communication and working power between the control system and the power management system and the electrical integrated management center, and the working power is 24V.

[0066] The charging power supply is an electric vehicle charging pile, and the high-voltage power distribution controller is connected to the electric vehicle charging pile through the vehicle socket.

[0067] After the high-voltage power distribution controller is connected to the electric vehicle charging pile, it obtains a 24V working power supply input, establishes communication with the electric vehicle charging pile, automatically identifies the charging state, and transfers the 24V working power supply to the high-voltage lithium-ion battery system; the high-voltage lithium-ion battery system obtains a 24V working power supply input and establishes communication with the high-voltage power distribution controller under the charging state; according to the battery voltage, temperature, state of charge (SOC) data, it selects to send a charging request to the high-voltage power distribution controller. Combining the charging time and charging safety, the charging request can be divided into fast charging, large current charging or small current charging requests, and the charging currents correspond to 0.5C, 0.2C and 0.1C of the battery pack capacity respectively. In this embodiment, the fast charging current is 21.5A, the large current charging current is 8.6A, and the small current charging current is 4.3A.

[0068] Under the charging state, the high-voltage power distribution controller receives data such as the total voltage, temperature, state of charge (SOC), charging request and fault information of 4 high-voltage lithium-ion battery systems. After confirming that there is no fault information feedback, it sends commands to close the positive terminal contactor and negative terminal contactor of the high-voltage lithium-ion battery system with the lowest total voltage in a communication manner; the high-voltage lithium-ion battery system with the lowest total voltage closes the positive terminal contactor and negative terminal contactor; after the high-voltage power distribution controller performs insulation detection, it sends commands to disconnect the positive terminal contactor and negative terminal contactor of the high-voltage lithium-ion battery system with the lowest total voltage in a communication manner; the high-voltage lithium-ion battery system with the lowest total voltage disconnects the positive terminal contactor and negative terminal contactor. The above steps are carried out in sequence until the insulation detection of all high-voltage lithium-ion battery systems is completed.

[0069] Control the closing of the positive terminal contactors and negative terminal contactors of 4 high-voltage lithium-ion battery systems according to the grid-connected charging strategy, so that they are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller, and then send an open charging command to the electric vehicle charging pile to start charging and charging protection. Specifically:

[0070] The high-voltage power distribution controller calculates the maximum voltage difference between each high-voltage lithium-ion battery system according to the voltage data of each high-voltage lithium-ion battery system;

[0071] If the maximum voltage difference < 5.239 (0.65×806) V, directly close the positive terminal contactors and negative terminal contactors of 4 high-voltage lithium-ion battery systems, so that they are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller;

[0072] When the maximum pressure difference ≥ 5.239V, first connect the high-voltage lithium-ion battery system with the lowest total voltage to the high-voltage busbar of the high-voltage power distribution controller and charge it at a current of 4.3 (43×0.1) A until the voltage difference from the second lowest total voltage high-voltage lithium-ion battery system is less than or equal to 0.806 (806×0.1%) V; connect the second lowest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; charge it at a current of 4.3 A until the voltage difference from the third lowest total voltage high-voltage lithium-ion battery system is less than or equal to 0.806 V; connect the third lowest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage busbar of the high-voltage power distribution controller; and so on until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller.

[0073] After all high-voltage lithium-ion battery systems are connected in parallel, send a charging command to the electric vehicle charging pile with the minimum value of the currents in the charging requests of 4 high-voltage lithium-ion battery systems as the total charging current and 806V as the total charging voltage to start charging until the current values in the charging requests of all high-voltage lithium-ion battery systems are the same, and then send a charging command to the electric vehicle charging pile with the sum of the currents in the charging requests of 4 high-voltage lithium-ion battery systems as the total charging current and 806V as the total charging voltage to start charging; stop charging when the voltage of any high-voltage lithium-ion battery system reaches the highest requested voltage, and the high-voltage power distribution controller controls to disconnect the positive terminal contactor and negative terminal contactor in all high-voltage lithium-ion battery systems.

[0074] In this embodiment, X is calculated to be 0.65 based on the battery internal resistance and the acceptable charging current; in order to reduce the charging current from the high-voltage one to the low-voltage one during parallel connection and improve the use safety, both Y and Z are taken as 0.1, and these two values can also be appropriately adjusted to be smaller, but the grid connection time will be extended.

[0075] The high-voltage power distribution controller receives data such as the total voltage, temperature, state of charge (SOC), charging request, and fault information of 4 high-voltage lithium-ion battery systems in the power supply state. After confirming that there is no fault information feedback, it sends a command to close the positive terminal contactor and negative terminal contactor of the high-voltage lithium-ion battery system with the lowest total voltage in a communication manner. The high-voltage lithium-ion battery system with the lowest total voltage closes the positive terminal contactor and negative terminal contactor. After the high-voltage power distribution controller performs insulation detection, it sends a command to disconnect the positive terminal contactor and negative terminal contactor of the high-voltage lithium-ion battery system with the lowest total voltage in a communication manner. The high-voltage lithium-ion battery system with the lowest total voltage disconnects the positive terminal contactor and negative terminal contactor. The above steps are carried out in sequence until all high-voltage lithium-ion battery systems complete the insulation detection.

[0076] The high-voltage power distribution controller receives the power supply requirement instruction from the electrical comprehensive management center, and controls the closing of the positive and negative contactors of 4 high-voltage lithium-ion battery systems according to the grid-connected power supply strategy, so that they are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller. Then, according to the requirements of the electrical comprehensive management center, close the soft-start contactor of a certain power supply channel, and close the main contactor of this power supply channel and disconnect the soft-start contactor after 1 s. The above-mentioned method of closing the power supply channel can be carried out synchronously until all power supply channels meet the power supply requirement instruction of the electrical comprehensive management center.

[0077] The grid-connected power supply strategy specifically refers to: the high-voltage power distribution controller calculates the maximum voltage difference between the high-voltage lithium-ion battery systems based on the voltage data of the 4 high-voltage lithium-ion battery systems;

[0078] When the maximum voltage difference < 5.239 V, directly close the positive and negative contactors of the 4 high-voltage lithium-ion battery systems, so that they are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller;

[0079] When the maximum voltage difference ≥ 5.239 V, first connect the high-voltage lithium-ion battery system with the highest total voltage to the high-voltage busbar of the high-voltage power distribution controller, then close the soft contactor to discharge until the voltage difference between the high-voltage lithium-ion battery system with the highest total voltage and the high-voltage lithium-ion battery system with the second highest total voltage ≤ 0.806 V, and connect the high-voltage lithium-ion battery system with the second highest total voltage in parallel to the high-voltage busbar of the high-voltage power distribution controller; discharge until the voltage difference with the high-voltage lithium-ion battery system with the third highest total voltage ≤ 0.806 V, and connect the high-voltage lithium-ion battery system with the third highest total voltage in parallel to the high-voltage busbar of the high-voltage power distribution controller; and so on, until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage busbar of the high-voltage power distribution controller, and then disconnect the soft contactor. According to the requirements of the electrical comprehensive management center, close the soft contactor of a certain power supply channel for 1 s, and close the main contactor of this power supply channel while disconnecting the soft contactor; the above-mentioned method of closing the power supply channel can be carried out synchronously until all power supply channels meet the power supply requirement instruction of the electrical comprehensive management center.

[0080] The airborne high-voltage battery parallel power supply and distribution system and control method of this embodiment not only meet the energy distributed design requirements and redundant power supply requirements of eVTOL, but also focus on solving the problems of safety, consistency, etc. brought by the parallel connection of 4 high-voltage lithium-ion battery systems and the power distribution redundant design problem, improving the reliability of the high-voltage battery parallel power supply and distribution system, and having functions such as parallel control of 4 high-voltage lithium-ion battery systems, 8-way motor output control, charging control of ground electric vehicle charging piles, short-circuit protection of output power lines, etc. The total stored energy is 120 KWh, the working temperature range is -40°C to 60°C, the working voltage range is 480 V to 806 V, the voltage detection accuracy is ±1%, and the maximum current of a single output terminal is 260 A, which can be applied to eVTOL or other similar aircraft.

Claims

1. Airborne high-voltage battery parallel power supply and distribution system, characterized in that: include: A high-voltage power distribution controller and at least two high-voltage lithium-ion battery systems, wherein the high-voltage power distribution controller includes a control system, a high-voltage bus bar, a communication and power input connector, and at least one output unit for connecting a load, wherein the communication and power input connector is used to connect each high-voltage lithium-ion battery system and external devices; When the external device is a charging power source: the high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage bus bar according to the grid-connected charging strategy, and sends charging instructions to the charging power source to start charging and charging protection; When the external device is an electrical integrated management center: the high-voltage distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage bus according to the power supply requirements of the electrical integrated management center and the grid power supply strategy, and closes the output unit as required.

2. The airborne high-voltage battery parallel power supply and distribution system according to claim 1, characterized in that: The high-voltage lithium-ion battery system includes a high-voltage battery pack, a power management system, a positive contactor and a negative contactor. The power management system is connected to the control system through a communication and power input connector, and the high-voltage lithium-ion battery system is connected to the high-voltage bus bar by closing the positive contactor and the negative contactor.

3. The airborne high-voltage battery parallel power supply and distribution system according to claim 1 or 2, characterized in that: It also includes a vehicle socket. When the external device is an electric vehicle charging pile, the high-voltage power distribution controller is connected to the electric vehicle charging pile through the vehicle socket.

4. An airborne high-voltage battery parallel power supply and distribution control method, applied to an airborne high-voltage battery parallel power supply and distribution system according to any one of claims 1 to 3, characterized in that: include: Step 1: Determine the working state of the onboard high-voltage battery parallel power supply and distribution system, which is a charging state or a power supply state; Step 2: Perform insulation testing on all high-voltage lithium-ion battery systems; Step 3: If the working state of the onboard high-voltage battery parallel power supply and distribution system is the charging state, then: the high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage bus bar according to the grid-connected charging strategy, and sends a charging instruction to the charging power supply to start charging and charging protection; If the working state of the onboard high-voltage battery parallel power supply and distribution system is the power supply state, then: the high-voltage power distribution controller controls the high-voltage lithium-ion battery system to be connected in parallel to the high-voltage bus according to the power supply requirements of the electrical integrated management center and the grid power supply strategy, and closes the output unit as required.

5. The airborne high-voltage battery parallel power supply and distribution control method according to claim 4 is characterized in that: The working state of the onboard high-voltage battery parallel power supply and distribution system is determined as follows: if the high-voltage power distribution controller is connected to the charging power supply, it is in the charging state; if the high-voltage power distribution controller is connected to the electrical integrated management center, it is in the power supply state.

6. The airborne high-voltage battery parallel power supply and distribution control method according to claim 4 is characterized in that: The steps for insulation testing are: The high-voltage power distribution controller sends a command to close the positive contactor and the negative contactor of the a-th high-voltage lithium-ion battery system; The ath high-voltage lithium-ion battery system closes the positive contactor and the negative contactor; The high-voltage power distribution controller sends a command to disconnect the positive contactor and the negative contactor of the a-th high-voltage lithium-ion battery system after performing insulation detection; the a-th high-voltage lithium-ion battery system disconnects the positive contactor and the negative contactor; The above process is carried out sequentially until all high-voltage lithium-ion battery systems have completed insulation testing.

7. The airborne high-voltage battery parallel power supply and distribution control method according to claim 4, characterized in that: The grid-connected charging strategy refers to: The high-voltage lithium-ion battery system sends charging requests to the high-voltage power distribution controller according to its own status; The high-voltage power distribution controller calculates the maximum voltage difference between each high-voltage lithium-ion battery system according to the voltage data of each high-voltage lithium-ion battery system; If the maximum voltage difference is less than X% of the full charge voltage of the high-voltage lithium-ion battery system, the positive contactor and the negative contactor of each high-voltage lithium-ion battery system are directly closed to connect them in parallel to the high-voltage busbar of the high-voltage power distribution controller; If the maximum voltage difference is ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, the high-voltage lithium-ion battery system with the lowest total voltage is first connected to the high-voltage bus of the high-voltage power distribution controller, and charged with the YCA current until the voltage difference between the high-voltage lithium-ion battery system with the second lowest total voltage is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system; and the process is repeated in sequence until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage bus of the high-voltage power distribution controller; After all high-voltage lithium-ion battery systems are connected in parallel, the minimum current value in each charging request is used as the total charging current, and the highest requested voltage is used as the total charging voltage. A charging instruction is sent to the electric vehicle charging pile to start charging until the current values ​​in the charging requests of all high-voltage lithium-ion battery systems are consistent; then the sum of the currents in each charging request is used as the total charging current, and the highest requested voltage is used as the total charging voltage, and a charging instruction is sent to the electric vehicle charging pile to start charging; when the voltage of any high-voltage lithium-ion battery system reaches the highest requested voltage, charging is stopped, and the high-voltage power distribution controller controls the disconnection of the positive and negative contactors in all high-voltage lithium-ion battery systems.

8. The airborne high-voltage battery parallel power supply and distribution control method according to claim 7, characterized in that: The charging request is fast charging, high current charging or low current charging.

9. The airborne high-voltage battery parallel power supply and distribution control method according to claim 8, characterized in that: X is 0.65, Y and Z are both 0.1, and the currents of fast charging, high current charging and low current charging correspond to 0.5C, 0.2C and 0.1C of the battery pack capacity respectively.

10. The airborne high-voltage battery parallel power supply and distribution control method according to any one of claims 4 to 9, characterized in that: The grid-connected power supply strategy refers to: The high-voltage power distribution controller calculates the maximum voltage difference between each high-voltage lithium-ion battery system according to the voltage data of each high-voltage lithium-ion battery system; If the maximum voltage difference is less than X% of the full charge voltage of the high-voltage lithium-ion battery system, the positive contactor and the negative contactor of each high-voltage lithium-ion battery system are directly closed to connect them in parallel to the high-voltage busbar of the high-voltage power distribution controller; If the maximum voltage difference is ≥ X% of the full charge voltage of the high-voltage lithium-ion battery system, first connect the high-voltage lithium-ion battery system with the highest total voltage to the high-voltage bus of the high-voltage distribution controller, then close the required output units, and discharge until the voltage difference between the high-voltage lithium-ion battery system with the highest total voltage and the second highest total voltage high-voltage lithium-ion battery system is less than or equal to Z% of the full charge voltage of the high-voltage lithium-ion battery system, and then connect the second highest total voltage high-voltage lithium-ion battery system in parallel to the high-voltage bus of the high-voltage distribution controller; proceed in sequence until all high-voltage lithium-ion battery systems are connected in parallel to the high-voltage bus of the high-voltage distribution controller.

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