Vehicle circuit system with reverse charging function

Abstract

The invention relates to the technical field of automobile charging, and particularly discloses a vehicle circuit system with a reverse charging function, comprising a main battery pack; the bidirectional inverter is electrically connected to the main battery pack and is configured to convert external alternating current into direct current to charge the main battery pack in a charging mode and convert the direct current of the main battery pack into alternating current to be output in a discharging mode; the charging control module is connected to the output end of the bidirectional inverter and used for processing input / output electric energy of different specifications; the multifunctional output interface comprises at least one alternating current interface and a direct current interface; and the system control unit, the integrated current detection module, the temperature monitoring module and the fault diagnosis module are respectively in communication connection with the bidirectional inverter, the charging control module and the output interface through a CAN bus. The vehicle power battery can reversely supply power to external equipment or other vehicles, meanwhile, the conventional charging function and the energy recycling function are compatible, and the method is suitable for new energy vehicles, hybrid electric vehicles and other scenes.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicle charging, and particularly relates to a vehicle circuit system with a reverse charging function. Background Art

[0002] With the rapid development of society and the increasing prominence of issues such as energy and environmental protection, electric vehicles are being increasingly emphasized for their advantages such as zero emissions and no pollution. The proportion and growth trend of electric vehicles are continuously increasing.

[0003] After retrieval, a Chinese invention patent with the patent application number CN202110908279.3 discloses a charge and discharge management method, terminal device and medium based on vehicle networking. The method includes: after detecting that a vehicle is inserted into a charging pile, obtaining vehicle management information; if the vehicle management information meets a preset discharge condition, performing vehicle-to-grid V2G discharge processing on the vehicle; if the vehicle management information meets a preset charging condition, performing grid-to-vehicle G2V charging processing on the vehicle. By adopting this invention, technical problems in the prior art such as being prone to charging peaks and not considering vehicle reverse power supply can be solved. Based on information such as the current remaining power of the vehicle, battery temperature, passenger compartment temperature, grid electricity price information or reserved vehicle use information collected, the vehicle can be intelligently charged during low electricity valleys to minimize the vehicle charging cost, and peak wave discharge can maximize the electricity revenue.

[0004] Another example is that a Chinese invention patent application with the patent application number CN202210954375.6 discloses a method, device, electronic device and computer-readable storage medium for off-peak power consumption of new energy vehicles. The method includes: obtaining an access time node and the stored power of a new energy vehicle; making a first comparison between the access time node and a preset peak power consumption time period; in the case where the access time node is within the peak power consumption time period, making a second comparison between the stored power of the new energy vehicle and a preset stored power threshold; in the case where the stored power of the new energy vehicle is not less than the stored power threshold, performing reverse power supply processing on the grid based on the stored power of the new energy vehicle. According to the solution of the embodiment of the present invention, the stored power of a new energy vehicle can be used to perform reverse power supply processing on the grid during peak power consumption periods, so that electric energy can be effectively utilized and the power resource allocation can be optimized.

[0005] Although the existing above-mentioned vehicle charging systems can meet basic usage requirements, they have the following defects:

[0006] 1. Low energy conversion efficiency: The efficiency of a conventional DC / AC inverter is less than 90%, and the output waveform distortion rate is high (such as patent CN201910123456.7);

[0007] 2. Poor compatibility: It cannot support the switching of multiple modes such as V2L (Vehicle-to-Load), V2V (Vehicle-to-Vehicle), and V2G (Vehicle-to-Grid) simultaneously.

[0008] 3. There are potential safety hazards: During reverse charging, there is a lack of dynamic monitoring of the load status, which is likely to cause overload or short circuit. Summary of the Invention

[0009] The technical problem to be solved by the present invention is to provide a vehicle circuit system with reverse charging function to solve the technical problems of low energy conversion efficiency, poor compatibility, and potential safety hazards in the existing vehicle charging system, in view of the above-mentioned defects of the prior art.

[0010] To solve the above technical problems, the technical solution of the present invention is as follows:

[0011] A vehicle circuit system with reverse charging function, comprising:

[0012] A main battery pack for storing vehicle driving electric energy and reverse charging output electric energy;

[0013] A bidirectional inverter electrically connected to the main battery pack, configured to convert external alternating current into direct current to charge the main battery pack in the charging mode, and convert the direct current of the main battery pack into alternating current for output in the discharging mode;

[0014] A charging control module connected to the output end of the bidirectional inverter, including a rectification unit and a voltage regulation unit, for processing input / output electric energy of different specifications;

[0015] A multi-functional output interface including at least one alternating current interface and a direct current interface, connected to the charging control module through a power distribution unit;

[0016] A system control unit integrating a current detection module, a temperature monitoring module, and a fault diagnosis module, and communicatively connected to the bidirectional inverter, the charging control module, and the multi-functional output interface respectively through a CAN bus.

[0017] Preferably, the bidirectional inverter adopts a full-bridge topology structure, supports the output voltage to be adjustable within the range of 110V - 240V, and the maximum output power is not less than 5kW.

[0018] Preferably, the rectification unit is configured as a three-level power factor correction circuit, and the voltage regulation unit includes a Buck-Boost bidirectional converter, which supports dynamic adjustment of the output voltage within the range of 48V - 800V.

[0019] Preferably, the multifunctional output interface integrates a communication module configured to execute a device handshake protocol, automatically identify the electrical parameters of the access device, and adjust the output mode. The communication module uses PLC power line carrier communication or Bluetooth 5.0 wireless communication.

[0020] Preferably, the system control unit is configured with:

[0021] A reverse charging priority management module for dynamically adjusting the maximum output power according to the remaining battery power of the vehicle;

[0022] An emergency power supply module for automatically switching to the uninterruptible power supply mode when a power grid power outage is detected;

[0023] A safety interlock module for forcibly disconnecting the reverse charging circuit when the vehicle starts.

[0024] Preferably, the emergency power supply module includes:

[0025] A preset power maintenance module for maintaining the power supply of critical loads for at least 24 hours;

[0026] A grid connection synchronization detection module for real-time monitoring of the power grid status to achieve seamless switching.

[0027] Preferably, the vehicle circuit system further includes a thermal management unit, and the thermal management unit includes:

[0028] A liquid cooling heat dissipation channel integrated on the heat dissipation substrate of the power device;

[0029] A distributed temperature sensor array arranged at key circuit nodes;

[0030] An adaptive fan control module for adjusting the heat dissipation strategy according to the temperature gradient.

[0031] Preferably, the vehicle circuit system integrates a V2X communication module configured to:

[0032] Receive grid dispatching instructions through the vehicle network;

[0033] Perform data interaction with the smart meter to optimize the time-of-use electricity price;

[0034] Provide a real-time energy management interface to the user terminal.

[0035] Preferably, the vehicle circuit system includes a redundant protection device, and the redundant protection device includes:

[0036] An overcurrent protection structure with a dual fuse and a latching relay in parallel;

[0037] A multi-stage surge suppression circuit;

[0038] Insulation monitoring unit, used to detect leakage current in real time and perform ground fault protection.

[0039] Preferably, when working in reverse charging, the system control unit prohibits the vehicle from entering the driving mode and locks the shift mechanism through a mechanical interlock device.

[0040] Adopting the above technical solution, a vehicle circuit system with reverse charging function provided by the present invention has the following beneficial effects: realizing efficient energy interaction between the power grid and the on-vehicle main battery pack through the setting of a bidirectional inverter, and wide voltage range adaptation between the main battery pack and external loads; through the built-in battery SOC estimation algorithm and dynamic equalization strategy in the system control unit, configured as: when charging forward, optimizing the charging curve according to the power grid load status, and when discharging reversely, dynamically adjusting the output parameters based on the power demand of external devices, realizing the lack of dynamic monitoring of the load status during reverse charging, avoiding overload or short circuit; the charging control module switches the charge and discharge circuit paths according to the mode instructions sent by the system control unit, supporting multi-scenario modes such as V2G (vehicle-to-grid), V2V (vehicle-to-vehicle), and V2L (vehicle-to-load), solving the pain points of low efficiency, poor compatibility, and insufficient safety of traditional vehicle charging systems, enabling the vehicle power battery to supply power reversely to external devices or other vehicles, while being compatible with conventional charging and energy recovery functions, and applicable to scenarios such as new energy vehicles and hybrid vehicles. Brief Description of the Drawings

[0041] Figure 1 It is a structural block diagram of the present invention;

[0042] In the figure, 1 - main battery pack, 2 - bidirectional inverter, 3 - charging control module, 4 - multi-functional output interface, 5 - system control unit, 51 - current detection module, 52 - temperature monitoring module, 53 - fault diagnosis module, 54 - reverse charging priority management module, 55 - emergency power supply module, 56 - safety interlock module. Detailed Embodiments

[0043] The following further describes the specific embodiments of the present invention with reference to the drawings. It should be noted here that the description of these embodiments is for helping to understand the present invention, but does not constitute a limitation to the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0044] In the description of the present invention, it should be understood that the orientation or positional relationships indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0045] In addition, the terms "first" and "second" are only used for descriptive purposes and should not be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0046] As Figure 1 shown, the vehicle circuit system with reverse charging function includes:

[0047] The main battery pack 1, which is used to store the electric energy for vehicle driving and the electric energy output for reverse charging;

[0048] The bidirectional inverter 2, which is electrically connected to the main battery pack 1 and is configured to convert external alternating current into direct current to charge the main battery pack in the charging mode, and convert the direct current of the main battery pack into alternating current for output in the discharging mode;

[0049] The charging control module 3, which is connected to the output end of the bidirectional inverter 2 and includes a rectifying unit and a voltage regulating unit, and is used to process input / output electric energies of different specifications;

[0050] The multi-functional output interface 4, which includes at least one alternating current interface and one direct current interface and is connected to the charging control module through a power distribution unit;

[0051] The system control unit 5, which integrates a current detection module 51, a temperature monitoring module 52 and a fault diagnosis module 53, and is communicatively connected to the bidirectional inverter, the charging control module and the multi-functional output interface respectively through a CAN bus.

[0052] It can be understood that the main battery pack 1 adopts a power battery pack, and the bidirectional inverter 2 is connected between the main battery pack 1 and the charging control module 3 and has the function of bidirectional electric energy conversion; in the forward charging mode, the external power supply charges the main battery pack 1 through the bidirectional inverter 2; in the reverse discharging mode, the main battery pack 1 supplies power to external electrical devices or the power grid through the bidirectional inverter 2.

[0053] Specifically, the bidirectional inverter 2 adopts a full-bridge topology structure, supports adjustable output voltage in the range of 110V - 240V, and the maximum output power is not less than 5kW. It can be understood that the bidirectional inverter 2 includes a bidirectional AC / DC conversion unit for the mutual conversion of AC and DC power; a bidirectional DC / DC conversion unit connected between the bidirectional AC / DC conversion unit and the main battery pack to achieve voltage level regulation.

[0054] Specifically, the rectification unit is configured as a three-level power factor correction circuit, and the voltage regulation unit includes a Buck-Boost bidirectional converter, which supports dynamic adjustment of the output voltage in the range of 48V - 800V. It can be understood that the charging control module, at least one set of relay arrays, is arranged at the input and output ends of the bidirectional AC / DC conversion unit; a semiconductor switch group is integrated into the power loop of the bidirectional DC / DC conversion unit; the conduction states of the relay arrays and the semiconductor switch group are dynamically controlled by the system control unit according to the working mode, which includes a high-voltage relay array and an SiC MOSFET switch group, and switches the charge and discharge paths according to the mode instruction, supporting multi-scenario modes such as V2G (vehicle-to-grid), V2V (vehicle-to-vehicle), and V2L (vehicle-to-load).

[0055] Specifically, the multifunctional output interface 4 integrates a communication module, which is configured to execute a device handshake protocol, automatically identify the electrical parameters of the access device and adjust the output mode, and the communication module uses PLC power line carrier communication or Bluetooth 5.0 wireless communication. It can be understood that the multifunctional output interface includes a national standard AC charging interface, which complies with the GB / T 20234.2 standard; a DC fast charging interface, which complies with the GB / T 20234.3 standard; a V2X communication interface, which supports vehicle-to-vehicle (V2V) and vehicle-to-grid (V2G) communication protocols; a composite charging port, which integrates a GB / T 20234 standard charging interface and a reverse discharge interface (supporting Type2 / CHAdeMO protocols); a V2X communication terminal, which is built with a PLC modem to achieve real-time data exchange with the grid dispatching center (transmission delay < 10ms).

[0056] Specifically, the system control unit 5 is configured with: a reverse charging priority management module 54, which is configured with a battery SOC estimation algorithm and a charging curve optimization algorithm, and integrates an adaptive load identification function and a hierarchical power output strategy, which is used to dynamically adjust the maximum output power according to the remaining power of the vehicle; an emergency power supply module 55, which is used to automatically switch to an uninterruptible power supply mode when a power outage is detected in the power grid; a safety interlock module 56, which monitors overvoltage, overcurrent, and overtemperature faults in real time and performs fuse protection, and is used to forcibly disconnect the reverse charging circuit when the vehicle is started. It can be understood that the emergency power supply module includes: a preset power maintenance module, which is used to maintain the power supply of key loads for at least 24 hours; a grid-connected synchronization detection module, which is used to monitor the power grid status in real time to achieve seamless switching; in V2L mode, the main battery pack is used for power supply first, and when the battery SOC is less than 20%, it automatically switches to the vehicle-mounted low-voltage system for power supply; in V2G mode, the discharge power is dynamically adjusted according to the power grid frequency modulation requirements (0-22kW continuously adjustable).

[0057] Specifically, the vehicle charging system also includes a thermal management unit, which includes: a liquid cooling heat dissipation channel integrated in the power device heat dissipation substrate; a distributed temperature sensor array arranged at key circuit nodes; and an adaptive fan control module for adjusting the heat dissipation strategy according to the temperature gradient. It can be understood that the thermal management unit uses a liquid cooling radiator and an NTC temperature sensor to control the junction temperature of the power device (≤125°C).

[0058] Specifically, the vehicle circuit system integrates a V2X communication module and is configured to: receive grid dispatch instructions through the Internet of Vehicles; interact with smart meters to optimize time-of-use electricity prices; and provide a real-time energy management interface to user terminals. Understandably, users can remotely view battery status, charging and discharging modes, and fault information, and control the charging and discharging process through mobile terminals such as mobile phones, improving user experience and intelligence.

[0059] Specifically, the vehicle circuit system includes a redundant protection device, which includes: an overcurrent protection structure in which a dual-circuit fuse is connected in parallel with a magnetic latching relay; a multi-stage surge suppression circuit; and an insulation monitoring unit for real-time detection of leakage current and execution of ground fault protection. It is understandable that when reverse charging is in operation, the system control unit prohibits the vehicle from entering the driving mode and locks the shift mechanism through a mechanical interlocking device; the redundant protection device integrates a reverse connection protection circuit, an insulation monitoring unit, and a multi-stage fuse mechanism, wherein the reverse connection protection circuit adopts a parallel Schottky diode and a MOSFET reverse cutoff structure, and the insulation monitoring unit detects the system leakage current (threshold ≤ 5mA) by injecting a 1kHz square wave signal.

[0060] It can be understood that the design of the present invention is reasonable and the structure is unique. By setting the bidirectional inverter 2, efficient energy interaction between the power grid and the vehicle-mounted main battery pack 1 is achieved, as well as wide voltage range adaptation between the main battery pack 1 and external loads. Through the built-in battery SOC estimation algorithm and dynamic balancing strategy in the system control unit 5, it is configured as follows: during forward charging, the charging curve is optimized according to the power grid load status, and during reverse discharging, the output parameters are dynamically adjusted based on the power demand of external devices, realizing the lack of dynamic monitoring of the load status during reverse charging and avoiding overload or short circuit. The charging control module switches the charge and discharge circuit paths according to the mode instructions sent by the system control unit, supports multi-scenario modes such as V2G (vehicle-to-grid), V2V (vehicle-to-vehicle), and V2L (vehicle-to-load), solves the pain points of low efficiency, poor compatibility, and insufficient safety of traditional vehicle charging systems, can realize reverse power supply from the vehicle power battery to external devices or other vehicles, and at the same time is compatible with conventional charging and energy recovery functions, and is applicable to scenarios such as new energy vehicles and hybrid vehicles.

[0061] The embodiments of the present invention have been described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the described embodiments. For those skilled in the art, without departing from the principle and spirit of the present invention, various changes, modifications, substitutions, and variations to these embodiments still fall within the protection scope of the present invention.

Claims

1. A vehicle circuit system with reverse charging function, characterized in that: Including: A main battery pack for storing vehicle driving electric energy and outputting reverse charging electric energy; A bidirectional inverter electrically connected to the main battery pack, configured to convert external alternating current into direct current to charge the main battery pack in the charging mode, and convert the direct current of the main battery pack into alternating current for output in the discharging mode; A charging control module connected to the output end of the bidirectional inverter, including a rectifying unit and a voltage regulating unit, for processing input / output electric energy of different specifications; A multi-functional output interface including at least one alternating current interface and a direct current interface, connected to the charging control module through a power distribution unit; A system control unit integrating a current detection module, a temperature monitoring module and a fault diagnosis module, and communicatively connected to the bidirectional inverter, the charging control module and the multi-functional output interface respectively through a CAN bus.

2. The vehicle circuit system with reverse charging function according to claim 1, characterized in that: The bidirectional inverter adopts a full-bridge topology structure, supports the output voltage to be adjustable within the range of 110V - 240V, and the maximum output power is not less than 5kW.

3. The vehicle circuit system with reverse charging function according to claim 1, characterized in that: The rectifying unit is configured as a three-stage power factor correction circuit, and the voltage regulating unit includes a Buck-Boost bidirectional converter, which supports the output voltage to be dynamically adjusted within the range of 48V - 800V.

4. The vehicle circuit system with reverse charging function according to claim 1, wherein: The multi-functional output interface integrates a communication module, configured to execute an equipment handshake protocol, automatically identify the electrical parameters of the access equipment and adjust the output mode, and the communication module adopts PLC power line carrier communication or Bluetooth 5.0 wireless communication.

5. The vehicle circuit system with reverse charging function according to claim 1, wherein: The system control unit is configured with: A reverse charging priority management module for dynamically adjusting the maximum output power according to the remaining battery level of the vehicle; An emergency power supply module for automatically switching to the uninterruptible power supply mode when a power grid power failure is detected; A safety interlock module for forcibly disconnecting the reverse charging circuit when the vehicle starts.

6. The vehicle circuit system with reverse charging function according to claim 5, characterized in that: The emergency power supply module includes: A preset power maintenance module for maintaining the power supply of critical loads for at least 24 hours; A grid-connected synchronization detection module for real-time monitoring of the power grid status to achieve seamless switching.

7. The vehicle circuit system with reverse charging function according to claim 1, characterized in that: It also includes a thermal management unit, and the thermal management unit includes: A liquid cooling heat dissipation channel integrated on the heat dissipation substrate of the power device; A distributed temperature sensor array arranged at key circuit nodes; An adaptive fan control module for adjusting the heat dissipation strategy according to the temperature gradient.

8. The vehicle circuit system with reverse charging function according to claim 1, characterized in that: The vehicle circuit system integrates a V2X communication module, configured to: Receive grid dispatching instructions through the vehicle network; Perform data interaction with the smart meter to optimize the time-of-use electricity price; Provide a real-time energy management interface to the user terminal.

9. The vehicle circuit system with reverse charging function according to claim 1, wherein: The vehicle circuit system includes a redundant protection device, and the redundant protection device includes: An overcurrent protection structure with a double-circuit fuse and a magnetic latching relay in parallel; A multi-stage surge suppression circuit; An insulation monitoring unit for real-time detection of leakage current and implementation of ground fault protection.

10. The vehicle circuit system with reverse charging function according to any one of claims 1-9, characterized in that: During reverse charging operation, the system control unit prohibits the vehicle from entering the driving mode and locks the shift mechanism through a mechanical interlock device.

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