Vehicle-to-vehicle charging and discharging device and charging system

Abstract

The application discloses a vehicle-to-vehicle charging and discharging device and a charging system, and relates to the technical field of automobile charging. The device comprises a power supply side first connector, first and second input branches arranged in parallel inside, and a loop connected with a discharging vehicle to receive initial direct current power in parallel; a power receiving side first connector, corresponding first and second output branches arranged in parallel inside, and a loop connected with a charging vehicle to output target direct current power in parallel; a conversion module connected with each input and output branch, used for step-down or step-up conversion of the initial direct current power and output of the target direct current power; and a control module connected with the discharging and charging vehicles and the conversion module, used for obtaining discharging and charging parameters and determining conversion parameters. The application realizes doubling of the discharging and charging current capacity by arranging two input branches and two output branches in parallel in a single connector and accessing the conversion module, and coordinating parameters by the control module, so that the energy transmission efficiency of vehicle-to-vehicle is improved.

Description

Technical Field

[0001] This application relates to the field of automotive charging technology, and more particularly to a vehicle-to-vehicle charging and discharging device and charging system. Background Technology

[0002] Vehicle-to-vehicle (V2V) charging and discharging refers to the transfer of energy from the battery of one vehicle to another through DC-DC conversion. It is mainly used for roadside assistance, emergency power supply, and fleet energy dispatch.

[0003] Most V2V devices on the market are single-gun, single-branch structures, meaning each charging gun is equipped with only one high-voltage channel. Limited by the single-channel capability, these devices cannot meet the high-current discharge requirements of commercial vehicles, nor can they fully utilize the total capacity and current capability of the multi-circuit parallel system of commercial vehicles, resulting in low discharge efficiency and insufficient charging speed.

[0004] The information disclosed in this background section is included only to enhance the understanding of the context of this disclosure, and therefore may contain information that does not constitute relevant technology currently known to those skilled in the art. Utility Model Content

[0005] This application provides a vehicle-to-vehicle charging and discharging device and charging system to solve the problem of limited current capacity of existing single-gun single-branch charging systems.

[0006] The technical solution adopted in this application is as follows.

[0007] In a first aspect, this application provides a vehicle-to-vehicle charging and discharging device, comprising: The first connector on the power supply side has a first input branch and a second input branch connected in parallel inside, which are respectively connected to the high-voltage battery circuit of the discharge vehicle to receive the initial DC power output by the discharge vehicle in parallel. The first connector on the power receiving side has a first output branch and a second output branch connected in parallel inside, which are respectively corresponding to the first input branch and the second input branch. They are respectively connected to the high-voltage battery circuit of the charging vehicle and are used to output the target DC power to the charging vehicle in parallel. The conversion module is connected to the first input branch, the second input branch, the first output branch, and the second output branch, respectively. It is used to step down or step up the initial DC power input through the first input branch and the second input branch to generate the target DC power, and output the target DC power to the charging vehicle through the first output branch and the second output branch. The control module is connected to the discharge vehicle, the charging vehicle, and the conversion module respectively. It is used to acquire the discharge parameters of the discharge vehicle and the charging parameters of the charging vehicle, and determine the conversion parameters for realizing the boost or buck conversion based on the discharge parameters and charging parameters, and output them to the conversion module to perform the corresponding buck or boost conversion.

[0008] This application significantly improves current carrying capacity and energy transmission efficiency by implementing multiple branches in parallel within a single connector and coordinating control with a unified DC-DC converter module. The control module ensures system stability and safety by monitoring and adjusting the operating parameters of each branch in real time, and effectively reduces the heat load and voltage drop of a single branch through precise control, thereby greatly improving energy transmission efficiency and charging speed. This solves the technical bottleneck of limited current in a single gun and single branch in existing electric vehicle charging technologies, and provides a more efficient charging and discharging solution for electric vehicles.

[0009] In conjunction with the first aspect, in an optional implementation, the control module is further configured to: generate a first set value corresponding to the first output branch and a second set value corresponding to the second output branch based on the distribution strategy of the target DC power output via the first output branch and the second output branch, and send them to the conversion module so that the power output by the first output branch and the second output branch reaches the first set value and the second set value.

[0010] This application utilizes a control module to generate setpoints corresponding to each output branch based on a target DC power distribution strategy. These setpoints are then sent to the conversion module, ensuring that the power output of each output branch reaches the preset setpoint. This approach not only allows for flexible adjustment of the power output of each branch according to actual needs, achieving more refined energy management and improving energy utilization efficiency, but also effectively reduces the risk of overload in a particular branch through dynamic power distribution. This enhances system stability and safety, ensuring the reliability and efficiency of the electric vehicle charging process.

[0011] In conjunction with the first aspect, in one alternative implementation, the device further includes: The current and voltage detection module is connected to the first output branch and the second output branch. It is used to detect the output current and output voltage of the first output branch and the second output branch, and report the actual current value and the actual voltage value of the output current to the control module. The controlled switches are connected in series on the first output branch and the second output branch, respectively. The control module is used to: determine whether an overcurrent has occurred based on a first comparison result between the actual current value and the rated current value, and to determine whether an overvoltage has occurred based on a second comparison result between the actual voltage value and the rated voltage value, so as to control the controlled switch to close or open according to the occurrence of overcurrent or overvoltage.

[0012] This application, by introducing a current and voltage detection module and a controlled switch, enables real-time monitoring and evaluation of the current and voltage conditions of each output branch. The control module, based on a comparison of the actual current value with the rated current value, and the actual voltage value with the rated voltage value, determines whether overcurrent or overvoltage has occurred, thereby promptly controlling the controlled switch to close or open in case of an anomaly. This design improves the system's safety and stability, preventing equipment damage and escalation of faults through rapid response. Simultaneously, it ensures that the electric vehicle is under optimal electrical conditions during charging, extending battery life and enhancing the user experience.

[0013] In conjunction with the first aspect, in one optional implementation, the control module is further configured to: send an adjustment signal to the conversion module based on the first comparison result and the second comparison result, so as to perform current limiting and voltage limiting control on the electrical energy output by the conversion module when overcurrent or overvoltage occurs.

[0014] This application adds a function to the control module to send adjustment signals to the conversion module based on a first comparison result and a second comparison result, thereby realizing current limiting and voltage limiting control of the electrical energy output by the conversion module in the event of overcurrent or overvoltage. This not only automatically adjusts the output in the event of an anomaly, preventing equipment damage and improving system safety and stability, but also optimizes power management and improves overall energy efficiency.

[0015] In conjunction with the first aspect, in one alternative implementation, the current-voltage detection module includes: The first current detection unit is connected in series on the first output branch to detect the first output current flowing through the first output branch and report the first current value of the first output current to the control module to determine whether an overcurrent has occurred in the first output branch. The first voltage detection unit is connected in parallel to both ends of the first output branch. It is used to detect the first output voltage flowing through the first output branch and report the first voltage value of the first output voltage to the control module to determine whether an overvoltage has occurred in the first output branch. The second current detection unit is connected in series on the second output branch to detect the second output current flowing through the second output branch and report the second current value of the second output current to the control module to determine whether an overcurrent has occurred in the second output branch. The second voltage detection unit is connected in parallel to both ends of the second output branch. It is used to detect the second output voltage flowing through the second output branch and report the second voltage value of the second output voltage to the control module to determine whether an overvoltage has occurred in the second output branch.

[0016] This application enables independent monitoring and management of multiple output branches by setting multiple detection units in the current and voltage detection module. It can detect and accurately judge the status of each branch in real time, improve the system's safety and stability, and facilitate expansion and maintenance, making it suitable for various power management scenarios.

[0017] In conjunction with the first aspect, in one alternative implementation, the device further includes: An insulation monitoring module is connected in parallel between the first output branch and the protective grounding wire, and between the second output branch and the protective grounding wire. It is used to monitor the insulation resistance to ground of the first output branch and the second output branch respectively, and report the insulation resistance to ground value to the control module. The control module is used to: determine whether an insulation fault has occurred based on the resistance value of the insulation resistance to ground, and control the controlled switch to close or open according to the occurrence of the insulation fault.

[0018] This application introduces an insulation monitoring module that can monitor the insulation resistance between each output branch and ground in real time and report the resistance value to the control module. The control module determines whether an insulation fault has occurred based on the insulation resistance value and controls the controlled switch to close or open if necessary. This design can detect and respond to insulation faults in a timely manner, prevent leakage accidents, protect personnel safety and normal equipment operation, and significantly improve the safety and reliability of the system.

[0019] In conjunction with the first aspect, in one alternative implementation, the insulation monitoring module includes: The first insulation monitoring unit is connected in parallel between the first output branch and the protective grounding wire to monitor the first insulation resistance to ground and report the resistance value of the first insulation resistance to ground to the control module. The second insulation monitoring unit is connected in parallel between the second output branch and the protective grounding wire. It is used to monitor the second insulation resistance to ground and report the resistance value of the second insulation resistance to ground to the control module.

[0020] This application sets up first and second insulation monitoring units, which are connected in parallel between their respective output branches and the protective grounding wire, to achieve independent monitoring and data reporting of the insulation resistance to ground of each output branch. This enables timely detection and early warning of insulation faults, ensuring the safety and stability of the system.

[0021] In conjunction with the first aspect, in one alternative implementation, the device further includes: The auxiliary power supply module has its input end connected to the conversion module and its output end connected to the control module, the current and voltage detection module, and the insulation monitoring module, respectively. It is used to draw power from the conversion module and supply power to the control module, the current and voltage detection module, and the insulation monitoring module.

[0022] This application introduces an auxiliary power module to obtain electrical energy from the conversion module and power the control module, current and voltage detection module, and insulation monitoring module. This not only simplifies the power management of the entire system, allowing each functional module to operate independently of an external power source, thereby improving the system's reliability and stability, but also reduces dependence on external power sources by using the power from the conversion module, enhancing the system's portability and adaptability.

[0023] In conjunction with the first aspect, in one alternative implementation, the device further includes: The second connector on the power supply side has a third input branch and a fourth input branch connected in parallel inside, which are respectively connected to the high-voltage battery circuit of the discharge vehicle; The second connector on the power receiving side has internally arranged a third output branch and a fourth output branch, which are respectively connected in parallel to the third input branch and the fourth input branch, and are respectively connected to the high-voltage battery circuit of the charging vehicle. The first input branch, the second input branch, the third input branch, and the fourth input branch are connected in parallel to receive the initial DC power in parallel. The first output branch, the second output branch, the third output branch, and the fourth output branch are connected in parallel to output the target DC power in parallel. The conversion module is connected to the first to fourth input branches and the first to fourth output branches respectively, and is used to step down or step up the initial DC power input through each input branch, and output the target DC power to the charging vehicle through the corresponding output branch.

[0024] This application achieves efficient DC power transmission between discharging and charging vehicles by setting up a second connector on the power supply side and the power receiving side, connecting multiple input and output branches in parallel, and a conversion module. It can convert power into step-down or step-up voltage under different voltage requirements, thereby improving the flexibility and efficiency of power transmission, ensuring stable power output, and adapting to the charging needs of various vehicles.

[0025] Secondly, this application also provides a charging system, which includes a discharging vehicle, a charging vehicle, and a vehicle-to-vehicle charging and discharging device according to the first aspect or any optional implementation of the first aspect.

[0026] The beneficial effects of the second aspect described above can be achieved by referring to the first aspect or any of the optional implementations of the first aspect, and will not be elaborated here. Based on the implementations provided above, this application can also be further combined to provide more implementations.

[0027] Other advantages, objectives and features of this application will be partly apparent from the description below, and partly understood by those skilled in the art through study and practice of this application. Attached Figure Description

[0028] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0029] Figure 1 This is one of the structural schematic diagrams of the vehicle-to-vehicle charging and discharging device provided in the embodiments of this application; Figure 2 This is the second schematic diagram of the vehicle-to-vehicle charging and discharging device provided in the embodiments of this application; Figure 3 This is a schematic diagram of the charging system provided in the embodiments of this application. Detailed Implementation

[0030] It should be noted that, in this application, the terms "exemplary" or "for example" are used to indicate that something is being described as an example, illustration, or illustration. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or design solutions. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner.

[0031] The term "and / or" as used in this application includes any and all combinations of one or more of the associated listed items. In this application, "at least one" means one or more, and "more than one" means two or more. The terms "first," "second," and other ordinal terms used in this application may be used to describe various constituent elements, but these constituent elements are not limited by these terms. The purpose of using these terms is solely to distinguish one constituent element from others and should not be construed as indicating or implying relative importance. For example, without departing from the scope of this application, a first constituent element may be named a second constituent element, and similarly, a second constituent element may be named a first constituent element.

[0032] Each circuit or other component may be described or referred to as "for" performing one or more tasks. In this context, "for" is used to imply a structure by indicating that the circuit / component includes a structure (e.g., a circuit system) that performs one or more tasks during operation. Therefore, even when the specified circuit / component is currently inoperable (e.g., not turned on), it can still be referred to as "for performing that task." Circuits / components used with the term "for" include hardware, such as circuits that perform operations.

[0033] Before introducing the embodiments of this application, the background technology involved in this application will be introduced first.

[0034] Vehicle-to-vehicle (V2V) charging and discharging transfers battery power from one vehicle to another via DC-DC conversion, commonly used for roadside assistance, emergency power supply, and energy allocation within a fleet. Existing V2V equipment generally employs a single-gun, single-branch design, meaning each charging gun contains only one high-voltage channel. Limited by the single-channel capacity, this not only fails to meet the high-current discharge requirements of commercial vehicles but also fails to fully utilize the overall capacity and current potential of multi-circuit parallel systems in commercial vehicles, resulting in low energy transfer efficiency and unsatisfactory charging speed.

[0035] In summary, the single-gun, single-branch solution in related technologies suffers from limited channel capacity, high losses and voltage drops, and difficulty in matching multi-circuit parallel systems, resulting in low energy replenishment efficiency and speed.

[0036] To address the aforementioned problems, embodiments of this application provide a vehicle-to-vehicle charging and discharging device. (Reference) Figure 1 , Figure 1 This is one of the structural schematic diagrams of the vehicle-to-vehicle charging and discharging device provided in the embodiments of this application.

[0037] like Figure 1 As shown, the vehicle charging and discharging device includes a power supply-side first connector 101, a power receiving-side first connector 102, a conversion module 103, and a control module 104. The power supply-side first connector 101 receives electrical energy from the discharging vehicle through internally connected first and second input branches, ensuring the stability and efficiency of energy reception. The power receiving-side first connector 102 connects to the charging vehicle and transmits the converted electrical energy to the high-voltage battery circuit of the charging vehicle in parallel through corresponding first and second output branches, ensuring efficient output. The conversion module 103 is a key component, responsible for stepping down or boosting the initial DC power input according to the needs of the charging vehicle to obtain a suitable target DC power, thereby ensuring compatibility between different vehicles. The control module 104 plays a crucial role, connecting to the discharging vehicle, the charging vehicle, and the conversion module 103, and is responsible for acquiring the discharging parameters of the discharging vehicle and the charging parameters of the charging vehicle. Based on these parameters, the control module 104 determines the conversion parameters for implementing boost or buck conversion and passes them to the conversion module 103 to perform the corresponding buck or boost conversion.

[0038] In some embodiments, the discharge vehicle is also a key component, requiring communication with the charging vehicle via message exchange according to the GB standard DC charging process. The discharge vehicle issues control commands to the conversion module 103 to lead the charging process. Specifically, the discharge vehicle, acting as the "power supply control entity," establishes a communication link through the first connector 101 on the power supply side, completing GB charging message exchanges such as identity authentication, parameter negotiation (including target voltage, current limits, insulation / fault status), start / stop commands, and process monitoring. After receiving the required parameters from the charging vehicle, the discharge vehicle sends corresponding voltage / current setting and start / stop control commands to the conversion module 103, enabling the conversion module 103 to perform boost / buck and current limiting control according to the negotiation results. During the charging process, the output is dynamically adjusted and linked for safety protection based on real-time messages. For ease of deployment, the discharge vehicle can be any vehicle model that already supports the GB charging protocol. Software strategies can be used to extend the control of the vehicle-to-vehicle charging and discharging devices and the protocol adaptation to the charging vehicle, thereby ensuring communication consistency between the two vehicles and safe and controllable energy transfer.

[0039] It should be noted that the above parameters can also be obtained from the messages sent by the discharging vehicle. The control quantities such as voltage and current used by the control module 201 for setting and output are all based on the messages provided by the discharging vehicle. The relevant requirements of the charging vehicle can be summarized by the discharging vehicle in the protocol interaction and transmitted through messages, thereby ensuring the dominant control position of the discharging vehicle as the power supply end and the consistency of the system.

[0040] For example, in a vehicle-to-vehicle charging scenario between two electric vehicles, assuming vehicle A has insufficient battery power while vehicle B has sufficient power, efficient energy transfer can be achieved using a dual-branch charging / discharging device. First, the first connector on the power supply side is connected to the high-voltage battery circuit of vehicle B. The charging / discharging device receives DC power from vehicle B through a first and second input branch connected in parallel. The two input branches operate simultaneously, allowing energy from vehicle B to flow into the charging / discharging device in parallel, improving input efficiency. Then, the first connector on the receiving side is connected to the high-voltage battery circuit of vehicle A. The device's two output branches, namely the first and second output branches, are ready to transmit energy to vehicle A in parallel. This dual-branch parallel output design allows vehicle A to receive energy more quickly, shortening charging time. The control module 104 acquires the discharge parameters of vehicle B (such as voltage and current) and the charging requirements of vehicle A (such as target voltage and current), and monitors these two branches in real time. Based on the parameters of each branch, the control module 104 calculates the required voltage and current conversions and instructs the conversion module 103 to adjust the input power by boosting or bucking it to meet the voltage requirements of vehicle A. The converted power is then transmitted in parallel to the battery of vehicle A through the first and second output branches. Each branch transmits power independently, improving the overall energy transfer efficiency. Parallel transmission reduces the burden on individual branches, ensuring that each branch operates at its optimal state and improving overall charging efficiency. Simultaneously, the control module 104 continuously monitors the voltage, current, and temperature of each input and output branch to ensure safe and effective charging throughout the process. This dual-branch parallel transmission design enables efficient energy sharing between vehicles, significantly improving charging speed and overall efficiency.

[0041] In some embodiments, the control module 104 of the charging and discharging device optimizes energy transfer through an intelligent allocation strategy. Specifically, the control module 104 formulates an energy allocation strategy based on factors such as the vehicle's actual charging needs, the current battery state, and overall system efficiency. This strategy aims to optimize the energy output of the first and second output branches. The control module 104 generates two setpoints: a first setpoint corresponding to the first output branch and a second setpoint corresponding to the second output branch. These setpoints represent the target energy output required by each branch. By sending these setpoints to the conversion module 103, the control module 104 ensures that the energy output of each branch accurately meets the system requirements, thereby achieving efficient and balanced energy transfer.

[0042] In some embodiments, reference Figure 2 , Figure 2 This is the second schematic diagram of the vehicle-to-vehicle charging and discharging device provided in the embodiments of this application. Figure 2As shown, the charging and discharging device also includes a current and voltage detection module 201 and multiple controlled switches to enhance the system's safety and reliability. The current and voltage detection module 201 is connected to the device's first and second output branches and is responsible for real-time monitoring of the output current and voltage of each branch. This module reports the detected actual current and voltage values ​​to the control module 104. The control module 104 uses this data to determine whether the system is in normal operating condition by comparing it with preset rated current and rated voltage values. If the actual current value exceeds the rated value, an overcurrent may occur; similarly, if the actual voltage value exceeds the rated value, there is a risk of overvoltage.

[0043] To handle potential overcurrent or overvoltage situations, the device is equipped with a controlled switch on each output branch. These switches are directly controlled by the control module 104. When the control module 104 detects an overcurrent or overvoltage, it instructs the corresponding controlled switch to open, quickly stopping the continued transmission of electrical energy and thus protecting the system from damage.

[0044] In addition to sampling required for overcurrent / overvoltage determination, the current and voltage detection module 201 can also use real-time current and voltage measurements for closed-loop control: on the one hand, it can be reported to the control module 104, which then issues current or voltage adjustment commands to the conversion module 103 (such as a DC-DC converter) to achieve closed-loop control; on the other hand, if the system supports direct communication between the current and voltage detection module 201 and the DC-DC converter, the real-time measurement values ​​can be directly reported to the DC-DC converter, which then performs closed-loop adjustment of the output current or voltage based on the data.

[0045] For example, in a practical application scenario, if the first output branch detects a current exceeding the rated value, the control module 104 will immediately trigger the controlled switch on that branch to disconnect, stopping the current flow and preventing circuit damage due to overcurrent. Through this design, the charging and discharging device can not only effectively transfer energy but also respond rapidly in abnormal situations, ensuring the safety of the system and the vehicle.

[0046] In some embodiments, the control module 104 not only addresses overcurrent or overvoltage by controlling the controlled switch, but also actively adjusts the output of the conversion module 103 to achieve current and voltage limiting control. When the current and voltage detection module 201 detects that the actual current or voltage value exceeds the rated value, the control module 104 determines whether the system is in an overcurrent or overvoltage state based on the first comparison result and the second comparison result. If an overcurrent or overvoltage is confirmed, the control module 104 sends an adjustment signal to the conversion module 103. These signals instruct the conversion module 103 to adjust its output parameters, thereby limiting the output current or voltage within a safe range. This current and voltage limiting control not only provides an additional layer of protection for the system, but also allows for timely adjustment of the output to adapt to momentary abnormal situations without completely interrupting power transmission.

[0047] For example, in a practical application scenario, when the first output branch detects a current value exceeding the rated current, the control module 104 can not only choose to disconnect the controlled switch of that branch, but also send a current-limiting signal to the conversion module 103. Upon receiving the signal, the conversion module 103 will immediately adjust its output current to reduce it to a safe rated range. The same logic applies to overvoltage conditions; the control module 104 can send a voltage-limiting signal to adjust the output voltage. This dynamic adjustment mechanism not only reduces unnecessary power interruptions but also improves the system's flexibility and response speed, enabling the charging and discharging device to maintain stable and efficient operation under various working conditions.

[0048] In some embodiments, the current and voltage detection module 201 is designed to include multiple detection units specifically for different output branches to ensure accurate monitoring of the current and voltage of each branch in the system. Specifically, a first current detection unit is connected in series in the first output branch, specifically for detecting the current flowing through that branch and transmitting the detected first current value to the control module 104. Simultaneously, a first voltage detection unit is connected in parallel across the two ends of the first output branch to detect the voltage of that branch and transmit the first voltage value to the control module 104. The control module 104 compares these actual detected values ​​with preset rated values ​​to determine whether there is an overcurrent or overvoltage in the first output branch, and thus takes corresponding protective measures.

[0049] Similarly, the second output branch is also equipped with a corresponding detection unit. A second current detection unit is connected in series in the second output branch to detect the current in that branch and report the second current value to the control module 104. A second voltage detection unit is connected in parallel with the second output branch to monitor its voltage and transmit the second voltage value to the control module 104. Through real-time monitoring by these detection units, the control module 104 can accurately determine whether overcurrent or overvoltage has occurred in the second output branch. In this way, each output branch is independently and accurately monitored, enabling timely protective measures to be taken in case of abnormal conditions (such as overcurrent or overvoltage) to ensure the safe and stable operation of the system.

[0050] For example, suppose the rated current of the first output branch is 10A, but the first current detection unit detects a current of 15A flowing through that branch, which clearly exceeds the rated value. In this case, the control module 104 will determine that an overcurrent has occurred in the first output branch and may disconnect the controlled switch of that branch through control logic. Similarly, if the second voltage detection unit detects a voltage higher than a preset safety threshold in the second output branch, the control module 104 will identify this as an overvoltage situation and quickly take measures to protect the safety of related equipment and personnel. Through this refined monitoring and protection mechanism, the system can effectively prevent potential electrical faults and ensure the safe operation of the output branches.

[0051] In some embodiments, the charging and discharging device not only focuses on the safety of current and voltage, but also pays special attention to the insulation status of the system. To this end, the device is equipped with an insulation monitoring module 202, which is connected in parallel between each output branch and the protective ground wire. This module is responsible for monitoring the insulation resistance to ground of the first and second output branches. Changes in insulation resistance can reveal potential insulation faults in the circuit, such as damage to the insulation layer or moisture infiltration. By monitoring these resistance values ​​in real time, the insulation monitoring module 202 can identify possible insulation problems at an early stage and report this resistance information to the control module 104.

[0052] The control module 104 determines the presence of an insulation fault based on the received insulation resistance to ground. If the insulation resistance is detected to be below a safe threshold, indicating a potential insulation fault, the control module 104 will take necessary measures. For example, it may instruct the corresponding controlled switch to open to prevent current from flowing through the damaged insulation area, thereby avoiding potential short circuits and leakage risks. In a practical application scenario, if the insulation resistance of the first output branch drops significantly, the control module 104 will immediately disconnect that branch to prevent any possible danger. This not only protects the safety of the local system but also prevents wider-ranging power accidents. In this way, the insulation monitoring module 202 and the control module 104 jointly ensure the safety and reliability of the system, especially in complex power environments.

[0053] It should be noted that the insulation resistance value obtained by the insulation monitoring module 202 can not only be used by the control module 104 to directly determine the insulation fault and execute the corresponding protection action locally based on the sampled value, but can also be reported by the control module 104 to the discharge vehicle for determining the insulation status.

[0054] In another embodiment, voltage detection, current detection, and insulation detection functions can be integrated on the same circuit board where the control module 104 is located. In this case, the current and voltage detection module 201 and the insulation monitoring module 202 can be implemented as onboard functional units of the control module 104. Their sampling and judgment results are uniformly processed by the control module 104 and corresponding control and protection strategies are executed. This simplifies the hardware structure, reduces wiring complexity, and improves system reliability and response speed while ensuring functional consistency.

[0055] In some embodiments, the insulation monitoring module 202 enhances system safety by setting up a dedicated insulation monitoring unit. Specifically, a first insulation monitoring unit is connected in parallel between the first output branch and the protective grounding wire to monitor the insulation resistance to ground of the first output branch in real time. This unit can detect the insulation status of the first output branch and transmit the measured insulation resistance value to the control module 104. The control module 104 compares the insulation resistance value with a preset safety threshold to determine whether the insulation status of the first output branch meets safety requirements. If the insulation resistance is found to be lower than the safety threshold, a potential leakage risk is considered, and the control module 104 can take necessary protective measures, such as disconnecting the relevant branch, to ensure the safety of the system and personnel.

[0056] Similarly, a second insulation monitoring unit is connected in parallel between the second output branch and the protective grounding wire, responsible for monitoring the insulation resistance to ground of the second output branch. The second insulation monitoring unit reports the measured insulation resistance value to the control module 104 to help determine the insulation status of the branch. In this way, the system can independently and accurately monitor the insulation status of each output branch.

[0057] It should be noted that the opening and closing of the insulation monitoring module 202 can be controlled by instructions sent by the discharge vehicle. After receiving the corresponding opening / closing instructions, the control module 104 will put the first and second insulation monitoring units into working or deactivated states respectively, so as to achieve collaborative management with the discharge vehicle and avoid unnecessary misjudgments and energy consumption.

[0058] For example, suppose the insulation resistance of the second output branch is normally 500kΩ, but the second insulation monitoring unit detects that it has dropped to 100kΩ, indicating a possible insulation failure or leakage. Upon receiving this information, the control module 104 will quickly identify this anomaly and may disconnect the branch to prevent a safety accident. Simultaneously, it will report the relevant anomaly information to the discharge vehicle, which will then terminate the entire process. Through this comprehensive insulation monitoring mechanism, the system can more effectively prevent electrical insulation faults, improving the overall safety and reliability of operation.

[0059] In some embodiments, the charging and discharging device includes an auxiliary power module 203 to ensure a stable power supply to the internal components. The input of the auxiliary power module 203 is connected to the conversion module 103, utilizing the power provided by the conversion module 103 for its own power supply. Its outputs are connected to the control module 104, the current and voltage detection module 201, and the insulation monitoring module 202, respectively. This design allows the auxiliary power module 203 to directly obtain power from the conversion module 103 and provide a stable power supply to critical monitoring and control components. Furthermore, before the discharging vehicle begins high-voltage discharging, the auxiliary power module can also provide the low-voltage power required for startup and standby of both the discharging and charging vehicles, ensuring the smooth start-up of the entire process. In this way, even if the main power supply fluctuates or is interrupted, the auxiliary power module 203 can still maintain the normal operation of these modules, ensuring that the system can continuously monitor and respond to any electrical anomalies.

[0060] For example, in an electric vehicle charging station, when a vehicle connects to the station, the conversion module 103 converts AC power into DC power suitable for battery charging. The auxiliary power module 203 obtains power from the conversion module 103 to power the control module 104 and other detection modules. Simultaneously, the auxiliary power module supplies power to both the discharging and charging vehicles before high-voltage discharge, ensuring that each unit is in a controlled, communicable, and interconnected safety protection state, creating the necessary conditions for subsequent high-voltage energy transfer. Thus, even if unexpected events occur during charging, such as grid voltage fluctuations, the auxiliary power module 203 can continue to provide power support for critical control and monitoring functions, avoiding monitoring failures or control interruptions due to momentary power outages, thereby ensuring the safety and reliability of the charging process.

[0061] In some embodiments, the device extends the input and output branches to four parallel connections by adding a connector on both the power supply side and the power receiving side, namely a second connector on the power supply side and a second connector on the power receiving side: the second connector on the power supply side contains the third and fourth input branches, which are connected in parallel to the high-voltage battery circuit of the discharging vehicle; the second connector on the power receiving side contains the corresponding third and fourth output branches, which are connected in parallel to the high-voltage battery circuit of the charging vehicle. Thus, the first to fourth input branches receive the initial DC power output from the discharging vehicle in parallel at their input ends, and the first to fourth output branches provide the target DC power to the charging vehicle in parallel at their output ends. The conversion module 103 connects to the four inputs and four outputs respectively, performs boost or buck conversion on each input power, and sends it out through the corresponding output branch, forming a multi-channel parallel energy transmission architecture. The significance of this parallel expansion is threefold: first, it dilutes the current in a single branch, reducing cable and terminal losses and heat generation; second, it increases the equivalent channel capacity and power redundancy, supporting higher charging and discharging power; and third, it facilitates multi-channel active current sharing at the control layer, resulting in more uniform temperature and automatic isolation and bypass in case of faults, thereby improving system reliability and better adapting to different voltage platforms.

[0062] For example, the battery voltage of the discharging vehicle is 720–820V, and the target is to replenish the power of the receiving vehicle on a 400–500V platform. The system simultaneously activates four input and four output branches. The conversion module 103 synchronously steps down the high-voltage side power and actively shares the current among the four branches. Under rated conditions, the total output power is 80kW, with each branch sharing approximately 20kW, significantly reducing the current and voltage drop of a single branch. When one branch is isolated due to temperature rise or fault, the other three branches automatically increase to approximately 26–27kW / branch to maintain approximately 80% power operation. During the SOC (State of Charge) increase phase of the receiving vehicle, the controller dynamically schedules the duty cycle and frequency of the four branches according to the constant current-constant voltage-power preservation curve, and fine-tunes the current sharing based on current sampling to avoid circulating current. If the system is changed to replenish the power of an 800V platform vehicle, the control strategy switches to boost mode, still outputting the target voltage through the four parallel systems, achieving high efficiency and high reliability of cross-platform V2V DC power replenishment.

[0063] Based on the same technical concept, embodiments of this application also provide a charging system. (See reference...) Figure 3 , Figure 3 This is a schematic diagram of the charging system provided in an embodiment of this application. Figure 3 As shown, the charging system includes a discharging vehicle 301, a charging vehicle 302, and a vehicle-to-vehicle charging and discharging device 303 of any of the above embodiments.

[0064] It should be noted that the order of description of the embodiments in this application is not intended to limit the priority of the embodiments.

[0065] Unless otherwise defined, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in this application and in its specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the application.

[0066] It should be noted that, unless otherwise specified, the term "connected" or "linked" in this application includes not only directly connecting two entities, but also indirectly connecting them through other entities that have beneficial improvement effects.

[0067] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many forms under the guidance of this application without departing from the spirit and scope of protection of the claims. All equivalent transformations made based on the technical concept of this application and the content of the description and drawings of this application, or direct / indirect applications in other related technical fields, are included within the scope of patent protection of this application.

Claims

1. A vehicle-to-vehicle charging and discharging device, characterized in that, include: The first connector on the power supply side has a first input branch and a second input branch connected in parallel inside, which are respectively connected to the high-voltage battery circuit of the discharge vehicle, and are used to receive the initial DC power output by the discharge vehicle in parallel. The first connector on the power receiving side has a first output branch and a second output branch connected in parallel inside, which are respectively corresponding to the first input branch and the second input branch. They are respectively connected to the high-voltage battery circuit of the charging vehicle and are used to output the target DC power to the charging vehicle in parallel. The conversion module is connected to the first input branch, the second input branch, the first output branch, and the second output branch, respectively, and is used to step down or step up the initial DC power input through the first input branch and the second input branch to generate target DC power, and output the target DC power to the charging vehicle through the first output branch and the second output branch. The control module is connected to the discharging vehicle, the charging vehicle, and the conversion module, respectively. It is used to acquire the discharging parameters of the discharging vehicle and the charging parameters of the charging vehicle, and determine the conversion parameters for implementing boost or buck conversion based on the discharging parameters and the charging parameters, and output them to the conversion module to perform the corresponding buck or boost conversion.

2. The vehicle-to-vehicle charging and discharging device according to claim 1, characterized in that, The control module is further configured to: generate a first set value corresponding to the first output branch and a second set value corresponding to the second output branch based on the distribution strategy of the target DC power output through the first output branch and the second output branch, and send them to the conversion module so that the power output by the first output branch and the second output branch reaches the first set value and the second set value.

3. The vehicle-to-vehicle charging and discharging device according to claim 1, characterized in that, The device further includes: A current and voltage detection module is connected to the first output branch and the second output branch, and is used to detect the output current and output voltage of the first output branch and the second output branch, and report the actual current value of the output current and the actual voltage value of the output voltage to the control module; Controlled switches are connected in series on the first output branch and the second output branch, respectively; The control module is used to: determine whether an overcurrent has occurred based on a first comparison result between the actual current value and the rated current value, and determine whether an overvoltage has occurred based on a second comparison result between the actual voltage value and the rated voltage value, so as to control the controlled switch to close or open according to the occurrence of the overcurrent or the overvoltage.

4. The vehicle-to-vehicle charging and discharging device according to claim 3, characterized in that, The control module is further configured to: send an adjustment signal to the conversion module based on the first comparison result and the second comparison result, so as to perform current limiting and voltage limiting control on the electrical energy output by the conversion module when the overcurrent or overvoltage occurs.

5. The vehicle-to-vehicle charging and discharging device according to claim 3, characterized in that, The current and voltage detection module includes: The first current detection unit is connected in series on the first output branch to detect the first output current flowing through the first output branch and report the first current value of the first output current to the control module to determine whether an overcurrent has occurred in the first output branch. The first voltage detection unit is connected in parallel to both ends of the first output branch. It is used to detect the first output voltage flowing through the first output branch and report the first voltage value of the first output voltage to the control module to determine whether the first output branch has overvoltage. The second current detection unit is connected in series on the second output branch to detect the second output current flowing through the second output branch and to report the second current value of the second output current to the control module to determine whether an overcurrent has occurred in the second output branch. The second voltage detection unit is connected in parallel to both ends of the second output branch. It is used to detect the second output voltage flowing through the second output branch and report the second voltage value of the second output voltage to the control module to determine whether the second output branch has overvoltage.

6. The vehicle-to-vehicle charging and discharging device according to claim 3, characterized in that, The device further includes: An insulation monitoring module is connected in parallel between the first output branch and the protective grounding wire and between the second output branch and the protective grounding wire, respectively, for monitoring the ground insulation resistance of the first output branch and the second output branch, and reporting the ground insulation resistance value to the control module. The control module is used to: determine whether an insulation fault has occurred based on the resistance value of the insulation resistance to ground, and control the controlled switch to close or open according to the occurrence of the insulation fault.

7. The vehicle-to-vehicle charging and discharging device according to claim 6, characterized in that, The insulation monitoring module includes: The first insulation monitoring unit is connected in parallel between the first output branch and the protective grounding wire, and is used to monitor the first insulation resistance to ground so as to report the resistance value of the first insulation resistance to ground to the control module. The second insulation monitoring unit is connected in parallel between the second output branch and the protective grounding wire, and is used to monitor the second insulation resistance to ground so as to report the resistance value of the second insulation resistance to ground to the control module.

8. The vehicle-to-vehicle charging and discharging device according to claim 6, characterized in that, The device further includes: An auxiliary power supply module has its input terminal connected to the conversion module and its output terminal connected to the control module, the current and voltage detection module, and the insulation monitoring module, respectively. It is used to draw power from the conversion module and supply power to the control module, the current and voltage detection module, and the insulation monitoring module.

9. The vehicle-to-vehicle charging and discharging device according to any one of claims 1-8, characterized in that, The device further includes: The second connector on the power supply side has a third input branch and a fourth input branch connected in parallel inside, which are respectively connected to the high-voltage battery circuit of the discharge vehicle; The second connector on the power receiving side has a third output branch and a fourth output branch connected in parallel inside, which are respectively corresponding to the third input branch and the fourth input branch, and are respectively connected to the high-voltage battery circuit of the charging vehicle. The first input branch, the second input branch, the third input branch, and the fourth input branch are connected in parallel to receive the initial DC power in parallel. The first output branch, the second output branch, the third output branch, and the fourth output branch are connected in parallel to output the target DC power in parallel. The conversion module is connected to the first to fourth input branches and the first to fourth output branches respectively, and is used to step down or step up the initial DC power input through each input branch, and output the target DC power to the charging vehicle through the corresponding output branch.

10. A charging system, characterized in that, This includes a vehicle for discharging, a vehicle for charging, and a vehicle-to-vehicle charging / discharging device as described in any one of claims 1-9.

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