Vehicle-to-vehicle type vehicle-mounted direct-current charging system and charging method for new energy electric vehicle

Abstract

The application relates to a new energy electric vehicle vehicle-to-vehicle type vehicle-mounted direct current charging system and a charging method, the system comprising an energy supply module, an energy conversion module, a direct current charging and discharging socket, a discharging gun and a controller, the energy supply module being connected with the controller and the energy conversion module respectively, and being used for providing energy to the energy conversion module under the control of the controller, the energy conversion module being used for obtaining charging demand of a charged vehicle after determining that a handshake with the charged vehicle succeeds, and reporting the demand to the controller; the controller is used for controlling the energy supply module to output electric energy to the energy conversion module according to the charging demand; the energy conversion module is also connected with the direct current charging and discharging socket, and is used for outputting the energy provided by the energy supply module to the direct current charging and discharging socket; and the method is based on the above direct current charging system. Compared with the prior art, the application adopts a vehicle-mounted component integrated vehicle-to-vehicle charging device, and has the advantages of low cost, high timeliness, strong charging capacity, wide application range and the like.

Description

Technical Field

[0001] The present invention relates to the field of vehicle-to-vehicle charging, and in particular to a vehicle-to-vehicle direct current charging system and charging method for a new energy electric vehicle. Background Art

[0002] With the rapid development of new energy electric vehicle technology, the number of electric vehicle users has increased rapidly. However, due to the limited range of the vehicle and the incomplete construction of charging facilities, electric vehicles often run out of power while driving and require rescue. It is also often inconvenient to charge in the surrounding area, and door-to-door charging services are needed.

[0003] In the prior art, a rescue vehicle equipped with vehicle-to-vehicle charging equipment can be used to rescue a vehicle that is out of power. For example, Chinese patent CN107834658A discloses a V2V emergency charging device for new energy vehicles and a charging control method thereof. The emergency charging device includes a soft start unit, a high-voltage relay, an input measurement unit, an output measurement unit, a charge and discharge management unit, an auxiliary power supply unit, a discharge protocol unit, and a charging protocol unit; the soft start unit is connected to the input measurement unit, and the high-voltage relay is connected to the input measurement unit and the output measurement unit respectively; the charge and discharge management unit is connected to the high-voltage relay, the input measurement unit, the output measurement unit, the auxiliary power supply unit, the discharge protocol unit, and the charging protocol unit. This emergency charging device requires an additional vehicle to be transported to the rescue site for rescue. Currently, the high-power DC charging devices for off-board electric vehicle rescue on the market are expensive, bulky, and heavy, resulting in high rescue costs, poor rescue timeliness, and high rescue costs.

[0004] In addition, Chinese patent CN201810898555.0 discloses a mobile charging vehicle power supply system, which uses a charging station installed on the vehicle to provide external power. This emergency charging device uses a DC charging station installed on the vehicle as a special rescue vehicle, which limits the vehicle's normal use and is limited to a dedicated vehicle, resulting in a small market. Summary of the Invention

[0005] The purpose of the present invention is to overcome the above-mentioned defects of the prior art and to provide a vehicle-to-vehicle DC charging system and charging method for new energy electric vehicles.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A vehicle-to-vehicle DC charging system for new energy electric vehicles. The system is applied to new energy vehicles and includes an energy supply module, an energy conversion module, a DC charging and discharging socket, a discharge gun, and a controller.

[0008] The energy supply module is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller.

[0009] The energy conversion module is configured to obtain the charging demand of the charged vehicle after determining that the handshake with the charged vehicle is successful, and report the demand to the controller;

[0010] The controller is configured to control the energy supply module to output electrical energy to the energy conversion module according to the charging demand;

[0011] The energy conversion module is also connected to the DC charging and discharging socket, and is also used to output the energy provided by the energy supply module to the DC charging and discharging socket.

[0012] Preferably, the energy supply module includes a power battery pack, and the power battery pack is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller.

[0013] Preferably, the energy supply module further includes a range-extending power generation device, which is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller.

[0014] Preferably, the range-extended power generation device includes an engine and a generator. The engine and the generator are mechanically coupled to generate electricity, and the output end of the generator is connected to a DC charging and discharging socket and a power battery pack through an energy conversion module.

[0015] Preferably, the energy conversion module includes an AC / DC converter, a voltage regulation module, and a discharge relay.

[0016] The AC-DC converter is used to convert the output AC power of the generator into DC power.

[0017] The voltage regulation module is used to regulate the voltage of AC-DC conversion or DC power from the power battery pack.

[0018] When the range-extending power generation device supplies power to the DC charging and discharging socket, the output end of the generator is connected to the DC charging and discharging socket through the AC-DC converter, the voltage regulating module, and the discharge relay in sequence.

[0019] When the power battery pack supplies power to the DC charge and discharge socket, the output end of the power battery pack is connected to the DC charge and discharge socket through the voltage regulation module and the discharge relay in sequence.

[0020] Preferably, the energy conversion module further comprises an insulation monitoring module for performing insulation monitoring on the output circuit of the voltage regulation module, and the insulation monitoring module is connected in parallel with the output end of the discharge relay.

[0021] Preferably, the energy conversion module further includes a discharge module for discharging the insulation monitoring voltage, and the discharge module is connected in parallel with the output end of the voltage regulation module.

[0022] Preferably, the energy conversion module further includes a current sensor and a voltage sensor. The current sensor is connected in series to the output end of the voltage regulation module, and the voltage sensor is connected in parallel to the output end of the discharge relay.

[0023] Preferably, the power battery pack includes a battery cell and a relay assembly, and the battery cell is connected to the DC charging and discharging socket and the energy conversion module through the relay assembly.

[0024] Preferably, the relay assembly includes a battery relay and a fast charging relay.

[0025] When the range-extending power generation device supplies power to the power battery pack or the power battery pack supplies power to the DC charging and discharging socket, the battery cell is connected to the energy conversion module through the battery relay.

[0026] When the power battery pack is powered by the DC charge and discharge socket, the battery cells are connected to the DC charge and discharge socket via the battery relay and the fast charge relay.

[0027] Preferably, the power battery pack further includes a BMS battery management subsystem, and the controller communicates with the BMS battery management subsystem and regulates the charging power of the power battery pack.

[0028] Preferably, the output end of the AC / DC converter is connected to the input end of the voltage regulation module through a high-voltage wiring harness and a docking copper plate, and the output end of the power battery pack is connected to the input end of the voltage regulation module through a high-voltage wiring harness and a docking copper plate.

[0029] A vehicle-to-vehicle DC charging method for a new energy electric vehicle is provided. The method is applied to a charging vehicle provided with the aforementioned DC charging system. The method is applied to a controller of the DC charging system. The method comprises:

[0030] After successfully shaking hands with the charged vehicle, it receives the charging request sent by the charged vehicle;

[0031] The output power of the energy supply module is controlled according to the charging demand, so that the energy supply module charges the charged vehicle through the energy conversion module, the DC charging and discharging socket, and the discharge gun in sequence until the preset charging cut-off condition is met and the charging stops.

[0032] Preferably, the output power of the energy supply module is controlled according to the charging demand, so that the energy supply module charges the charged vehicle through the energy conversion module, the DC charging and discharging socket, and the discharge gun in sequence, including:

[0033] Determine whether the power battery pack and range-extending power generation device meet discharge conditions;

[0034] If the power battery pack and the range-extending power generation device both meet the discharge conditions, controlling the power battery pack and the range-extending power generation device to simultaneously provide energy to the energy conversion module;

[0035] If the power battery pack meets the discharge condition and the range-extending power generation device does not meet the discharge condition, controlling the power battery pack to provide energy to the energy conversion module;

[0036] If the range-extending power generation device meets the discharge condition and the power battery pack does not meet the discharge condition, the controller controls the range-extending power generation device to provide energy to the energy conversion module;

[0037] If the power battery pack and the range-extending power generation device do not meet the discharge conditions, the energy supply module is controlled to stop providing energy to the energy conversion module.

[0038] Preferably, the charging start time and the discharge amount of the charging vehicle are adjusted by a central control device in the charging vehicle or a mobile terminal connected to the charging vehicle.

[0039] Compared with the prior art, the present invention has the following advantages:

[0040] (1) The DC charging system of the present invention is installed on a new energy electric vehicle, and can use the extended range power generation device and power battery pack on the new energy electric vehicle to supply energy and charge the charged vehicle. The vehicle-to-vehicle DC system is integrated with the electric vehicle structure, and no additional charging device is required. The rescue efficiency is high and the use cost is low;

[0041] (2) The DC charging system of the present invention is integrated and mounted on a new energy electric vehicle. The appearance of the vehicle is the same as that of an ordinary electric vehicle, but it can provide an additional vehicle-to-vehicle DC fast charging function, which is widely used and highly effective, avoiding the limitation of dedicated vehicles;

[0042] (3) The present invention uses an energy conversion module to convert and regulate the output voltage of the range-extending power generation device and the power battery pack, so that the DC fast charging system of the present invention can adjust the output power according to the charging needs of the charged vehicle, and has a wide range of applications and can charge a wide range of types of vehicles;

[0043] (4) The present invention has multiple charging power supply modes and can switch between multiple charging modes according to the status and charging needs of the charging vehicle and the charged vehicle. It can perform multiple charging modes such as single-range extended power generation device charging, single power battery pack charging, and hybrid charging. It has a wide output power range and is suitable for different rescue scenarios and rescue conditions, with good universality.

[0044] (5) The present invention utilizes an energy conversion module and a controller to obtain the charging requirements of the charged vehicle and makes targeted output power adjustments, resulting in high energy utilization and charging efficiency.

[0045] (6) The output ends of the range-extending power generation device and the power battery pack of the present invention are connected to the input end of the voltage regulation module through high-voltage wiring harnesses and docking copper plates, avoiding the situation where the outputs of the two are connected in parallel. There is no high current requirement for the external wiring harness, which effectively reduces production costs and has good economic efficiency.

[0046] (7) The charging method of the present invention can adjust the power according to the charging demand of the charged vehicle and effectively control the charging process according to the preset charging cut-off conditions. It is easy to operate, applicable to different types of charged vehicles, and has a good charging effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a structural schematic diagram of the DC charging system of the present invention;

[0048] Figure 2 This is a detailed structural diagram of the DC charging system of the present invention;

[0049] Figure 3 Flowchart of the charging method of the present invention.

[0050] Among them, 1. Engine, 2. Generator, 3. Power battery pack, 31. Battery relay, 32. Fast charging relay, 33. Battery cell, 34. BMS battery management subsystem, 4. Energy conversion module, 41. AC / DC converter, 42. Discharge relay, 43. Voltage sensor, 44. Current sensor, 45. Discharge relay, 46. Discharge resistor, 47. Voltage regulation module, 48. Insulation monitoring module, 5. Controller, 6. DC charge and discharge socket, 7. Discharge gun, 8. Charging socket, 9. Charged vehicle, 10. High-voltage wiring harness, 11. Power CAN, 12. 250K internal CAN. DETAILED DESCRIPTION

[0051] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Note that the following embodiments are merely illustrative in nature and the present invention is not intended to limit its applicable objects or uses, and the present invention is not limited to the following embodiments.

[0052] Example

[0053] A vehicle-to-vehicle DC charging system for a new energy electric vehicle is disclosed. The system is applied to new energy vehicles. In this embodiment, the system is installed on an extended-range new energy electric vehicle. Its energy conversion module includes an extended-range power generation device and a power battery pack 3, which can perform vehicle-to-vehicle DC fast charging for the vehicle to be charged.

[0054] The DC charging system of the present invention is as follows Figure 1 The above-mentioned method includes an energy conversion module 4, a DC charging and discharging socket 6, and a discharge gun 7 provided on the new energy electric vehicle. The two ends of the discharge gun 7 are respectively connected to the DC charging and discharging socket 6 and the charged vehicle 9.

[0055] The energy supply module of the present invention is respectively connected to the controller and the energy conversion module, and is used to provide energy to the energy conversion module under the control of the controller. The energy conversion module is used to obtain the charging requirements of the charged vehicle after determining that the handshake with the charged vehicle is successful, and report the requirements to the controller; the controller is used to control the energy supply module to output electrical energy to the energy conversion module according to the charging requirements; the energy conversion module is also connected to the DC charging and discharging socket, and is also used to output the energy provided by the energy supply module to the DC charging and discharging socket.

[0056] For the above components, Figure 2 As shown, specifically:

[0057] The range-extended power generation device is connected to a DC charging / discharging receptacle 6 via an energy conversion module 4, providing power to the DC charging / discharging receptacle 6. Similar to existing range-extended vehicles, this embodiment also directly supplies power to the power battery pack 3. Specifically, the range-extended power generation device comprises an engine 1 and a generator 2. The engine 1 and generator 2 are mechanically coupled to generate electricity, and the output of the generator 2 is connected to the DC charging / discharging receptacle 6 and the power battery pack 3 via the energy conversion module 4.

[0058] The power battery pack 3 is also connected to the DC charging and discharging socket 6 via the energy conversion module 4, capable of supplying power to the DC charging and discharging socket 6. Specifically, it includes battery cells 33, a relay assembly, and a BMS battery management subsystem 34. The relay assembly includes a battery relay 31 and a fast-charging relay 32. The controller 5 communicates with the BMS battery management subsystem 34 to regulate the charging power of the power battery pack 3.

[0059] For the relay assembly of the power battery pack 3, when the extended-range power generation device supplies power to the power battery pack 3 or the power battery pack 3 supplies power to the DC charge and discharge socket 6, the battery cell 33 is connected to the energy conversion module 4 through the battery relay 31; when the DC charge and discharge socket 6 supplies power to the power battery pack 3, the battery cell 33 is connected to the DC charge and discharge socket 6 through the battery relay 31 and the fast charge relay 32.

[0060] The energy conversion module 4 includes an AC / DC converter 41 , a voltage regulation module 47 , a discharge relay 42 , an insulation monitoring module 48 , a discharge module, a current sensor 44 , and a voltage sensor 43 . The energy conversion module 4 is also used to obtain the charging demand information of the charged vehicle and communicate it to the controller 5 .

[0061] Among them, the AC / DC converter 41 is used to convert the AC power output of the generator 2 into DC power. The voltage regulator module 47 is used to regulate the voltage of the DC power converted from AC to DC or from the power battery pack 3. The insulation monitoring module 48 is connected in parallel with the output of the discharge relay 42 and is used to monitor the insulation of the output circuit of the voltage regulator module 47. The discharge module is connected in parallel with the output of the voltage regulator module 47. The current sensor 44 is connected in series with the output of the voltage regulator module 47. The voltage sensor 43 is connected in parallel with the output of the discharge relay 42 to detect the current and voltage outputted by the energy conversion module 4 to the DC charging and discharging socket 6.

[0062] Based on the structure of the energy conversion module 4, when the extended-range power generation device supplies power to the DC charge and discharge socket 6, the output end of the generator 2 is connected to the DC charge and discharge socket 6 through the AC-DC converter 41, the voltage regulation module 47, and the discharge relay 42 in sequence. When the power battery pack 3 supplies power to the DC charge and discharge socket 6, the output end of the power battery pack 3 is connected to the DC charge and discharge socket 6 through the voltage regulation module 47 and the discharge relay 42 in sequence.

[0063] The controller 5 controls the range-extending power generation device and the power battery pack 3 to output power to the energy conversion module according to the charging demand information. In this embodiment, the controller 5 adopts a vehicle controller to reduce equipment costs.

[0064] More specifically, in this embodiment:

[0065] The battery relay 31 includes a main positive relay and a main negative relay. The positive output of the battery cell 33 is connected to the positive input line of the voltage regulator module 47 through the main positive relay and the high-voltage wiring harness 10, and is connected to the positive wiring of the DC charge and discharge socket 6 through the fast-charge relay 32. The negative output of the battery cell 33 is connected to the negative input line of the voltage regulator module 47 through the main negative relay and the high-voltage wiring harness 10, and is connected to the negative wiring of the DC charge and discharge socket 6. The battery relay 31 also includes a pre-charge relay and a pre-charge resistor connected in series. The pre-charge relay and pre-charge resistor are connected in parallel with the main positive relay.

[0066] The AC converter is an IGBT power module, the voltage regulator module 47 is a silicon carbide tube voltage regulator, and the discharge module includes a discharge relay 45 and a discharge resistor 46 arranged in series. The discharge relay 42 includes a positive discharge relay and a negative discharge relay. The positive output of the voltage regulator module 47 is connected in series with the current sensor 44 and the positive discharge relay, and then connected to the positive terminal of the DC charge and discharge socket 6. The negative output of the voltage regulator module 47 is connected in series with the negative discharge relay, and then connected to the negative terminal of the DC charge and discharge socket 6. The discharge module is installed in parallel with the positive and negative outputs of the voltage regulator module 47. The insulation monitoring module 48 is installed in parallel at the ends of the positive and negative discharge relays.

[0067] In this embodiment, the DC charging and discharging socket 6 is connected to the energy conversion module 4 via the 250K internal CAN 12, which in turn is connected to the controller 5 via the power CAN 11. During operation, the energy conversion module 4 establishes charging power demand communication and control with the BMS battery management module 24 of the charged vehicle 9 via the internal CAN, obtains the charging demand information of the charged vehicle 9, and transmits this charging demand information to the controller 5 via the power CAN 11, which then adjusts and controls the charging power.

[0068] In another embodiment of the present invention, the output of the AC / DC converter 41 is connected to the input of the voltage regulator module 47 via a high-voltage wiring harness 10 and a copper plate. Similarly, the output of the power battery pack 3 is connected to the input of the voltage regulator module 47 via a high-voltage wiring harness 10 and a copper plate. This connection effectively reduces wiring harness costs and improves economic efficiency.

[0069] The DC charging and discharging socket 6 of the present invention is both a power supply socket and a charging socket for a new energy electric vehicle, and is used to charge the vehicle to be charged and the power battery pack 3 respectively. In another embodiment of the present invention, the DC charging and discharging socket 6 is independently provided. When the present invention is in operation, it includes the following working states:

[0070] (1) The range-extending generator unit supplies power to the vehicle to be charged independently. In this state, the engine 1 and generator 2 are running, the positive discharge relay and the negative discharge relay are closed, and the current generated by the range-extending generator unit is converted into DC power by the AC / DC converter 41. After voltage regulation by the voltage regulating module 47, it is output to the vehicle to be charged through the DC charging and discharging socket 6.

[0071] (2) The power battery pack 3 supplies power to the vehicle to be charged. In this state, the positive discharge relay and the negative discharge relay are closed, and the output DC power of the power battery pack 3 is regulated by the voltage regulating module 47 and then output to the vehicle to be charged through the DC charging and discharging socket 6.

[0072] (3) The range-extending power generation device and the power battery pack 3 simultaneously supply power to the vehicle to be charged. In this state, the engine 1 and the generator 2 are running, the positive discharge relay and the negative discharge relay are closed, and the current generated by the range-extending power generation device is converted into DC power by the AC / DC converter 41. The DC power output from the AC / DC converter 41 and the DC power output from the power battery pack 3 are input to the voltage regulating module 47. After voltage regulation, the voltage regulating module 47 outputs the DC power to the vehicle to be charged through the DC charging and discharging socket 6.

[0073] (4) The range-extending power generation device independently supplies power to the power battery pack 3. In this state, the engine 1 and generator 2 are running, the positive discharge relay and the negative discharge relay are disconnected, and the current generated by the range-extending power generation device is converted into DC power by the AC / DC converter 41. The DC power output of the AC / DC converter 41 is fed into the power battery pack 3 for charging.

[0074] (5) The range-extending power generation device simultaneously supplies power to the vehicle to be charged and the power battery pack 3. This state differs from state 1 in that the main positive relay and the main negative relay are closed, and the output DC power of the AC / DC converter 41 is also fed into the power battery pack 3 for charging.

[0075] (6) The DC charging and discharging socket 6 is connected to an external charging pile, and the power battery pack 3 is directly powered by the external charging pile.

[0076] The present invention also provides a vehicle-to-vehicle DC charging method for new energy electric vehicles. The method is applied to a charging vehicle provided with the above-mentioned DC charging system. The method is applied to a controller of the DC charging system, comprising:

[0077] After successfully shaking hands with the charged vehicle, it receives the charging request sent by the charged vehicle;

[0078] The output power of the energy supply module is controlled according to the charging demand, so that the energy supply module charges the charged vehicle through the energy conversion module, the DC charging and discharging socket 6, and the discharge gun 7 in sequence until the preset charging cut-off condition is met and the charging stops.

[0079] More specifically, in this embodiment, Figure 3 As shown, the method includes the following steps:

[0080] S0: Check whether the vehicle and DC charging system are normal. If so, proceed to step S1; otherwise, stop charging.

[0081] S1: The charging vehicle and the charged vehicle are connected through the discharge gun 7. The two ends of the discharge gun 7 are respectively connected to the DC charging and discharging socket 6 of the charging vehicle and the charging socket of the charged vehicle. The charging vehicle and the charged vehicle communicate and shake hands.

[0082] S2: The controller receives the charging demand from the charged vehicle. In step S2, a demand acquisition module can be configured to connect to the charged vehicle via the discharge gun 7 to acquire the charging demand of the charged vehicle and transmit it to the controller. Alternatively, the energy conversion module 4 in this embodiment can be used to acquire the charging demand of the charged vehicle and transmit it to the controller.

[0083] S3: Set the charging start time, discharge amount, and charging cutoff condition. When the charging start time is reached, the controller controls the output power of the energy supply module according to the charging demand, so that the energy supply module charges the charged vehicle through the energy conversion module 4, the DC charging and discharging socket 6, and the discharge gun 7 in sequence until the preset charging cutoff condition is met and charging stops. In addition, when the discharge amount of the charging vehicle reaches the preset value, charging will also stop.

[0084] Specifically, in step S3, the charging start time and discharge amount of the charging vehicle are adjusted via the central control device in the charging vehicle or a mobile terminal connected to the charging vehicle. In step S4, the charging cutoff condition for the charging vehicle is set via the central control device in the charging vehicle or a mobile terminal connected to the charging vehicle. The charging cutoff condition may be that the fuel level in engine 1 falls below a preset fuel level. In this embodiment, the central control device is the vehicle's central control screen, and the mobile terminal is the user's mobile phone. The charging start time and discharge amount of the charging vehicle can be adjusted and the charging cutoff condition set via the mobile phone application.

[0085] In addition, regarding the controller of the present invention controlling the output power of the energy supply module, in step S3 of this embodiment, the controller determines whether the power battery pack 3 and the range-extending power generation device meet the discharge conditions respectively;

[0086] If both the power battery pack 3 and the range-extended power generation device meet the discharge conditions, the controller controls the power battery pack 3 and the range-extended power generation device to simultaneously provide energy to the energy conversion module; if the power battery pack 3 meets the discharge conditions and the range-extended power generation device does not meet the discharge conditions, the controller controls the power battery pack 3 to provide energy to the energy conversion module; if the range-extended power generation device meets the discharge conditions and the power battery pack 3 does not meet the discharge conditions, the controller controls the range-extended power generation device to provide energy to the energy conversion module.

[0087] Furthermore, the discharge conditions of the power battery pack 3 include the remaining power of the power battery pack 3 being greater than the preset discharge power and the power battery pack 3 being fault-free. The discharge conditions of the range-extending power generation device are the remaining fuel level of the engine being greater than the preset fuel level and the range-extending power generation device being fault-free.

[0088] According to the above output power control strategy, the controller 5 controls the output power of the range-extending power generation device and the power battery pack 3 according to the charging demand. Specifically, it includes the following four forms:

[0089] (1) The range-extended generator device meets the discharge conditions, while the power battery pack 3 does not. The range-extended generator device alone supplies power to the vehicle to be charged. In this state, the engine 1 and generator 2 are running, the positive discharge relay and the negative discharge relay are closed, and the current generated by the range-extended generator device is converted to DC power by the AC / DC converter 41. After voltage regulation by the voltage regulation module 47, it is output to the vehicle to be charged through the DC charging and discharging socket 6. The controller 5 adjusts the output power of the engine 1 and generator 2 according to the charging demand.

[0090] A specific example of the first form is: when the controller 5 determines that the remaining oil level of the range-extending power generation device is higher than the set threshold and there is no fault, and the remaining power of the power battery pack 3 is lower than the set threshold and there is no fault, and the controller 5 receives a charging power of 30kW corresponding to the charging voltage and current required by the charged vehicle, the controller 5 controls the energy conversion module 4, the engine 1, and the generator 2 to output 30kW of power to charge the charged vehicle.

[0091] (2) The power battery pack 3 meets the discharge conditions, while the range-extending generator does not. The power battery pack 3 provides independent power to the vehicle to be charged. In this state, the positive discharge relay and the negative discharge relay are closed, and the DC power output from the power battery pack 3 is regulated by the voltage regulating module 47 and then output to the vehicle to be charged via the DC charging and discharging socket 6. The controller 5 adjusts the output power of the engine 1, the generator 2, and the power battery pack 3 according to the charging demand.

[0092] A specific example of the second form is: when the controller 5 determines that the remaining oil level of the extended-range power generation device is lower than the set threshold and there is no fault, and the remaining power of the power battery pack 3 is higher than the set threshold and there is no fault, and receives a charging power of 30kW corresponding to the charging voltage and current required by the charged vehicle, the controller 5 does not start the energy conversion module 4, the engine 1, and the generator 2, and its power generation power output is 0kW; it enables the power battery pack 3 to independently discharge 30kW to charge the charged vehicle.

[0093] (3) The power battery pack 3 and the range-extending power generation device both meet the discharge conditions, and the range-extending power generation device and the power battery pack 3 simultaneously supply power to the vehicle to be charged. In this state, the engine 1 and the generator 2 are running, the positive discharge relay and the negative discharge relay are closed, and the current generated by the range-extending power generation device is converted into DC power by the AC / DC converter 41. The DC power output of the AC / DC converter 41 and the DC power output of the power battery pack 3 are input into the voltage regulating module 47. After voltage regulation by the voltage regulating module 47, the DC power output is output to the vehicle to be charged via the DC charging and discharging socket 6. In this state, the range-extending power generation device and the power battery pack 3 can output energy according to the output power ratio preset by the controller 5.

[0094] A specific example of the third form is: the controller 5 determines that the remaining fuel level of the range-extending power generation device is higher than the set threshold and there is no fault, and the remaining power level of the power battery pack 3 is higher than the set threshold and there is no fault. When the controller 5 receives a charging power of 30kW corresponding to the charging voltage and current required by the charged vehicle, the controller 5 regulates the power generation output of the energy conversion module 4, the engine 1, and the generator 2 by 15W, and enables the battery to discharge 15kW at the same time, for a total of 30kW to be charged to the charged vehicle; during the charging process, the power generation power can be dynamically adjusted to match the discharge power of the power battery pack 3 according to the fuel level of the range-extending system and the power level of the power battery pack 3. For example, when there is more electricity and less fuel, the power generation power output is regulated by 10kW, and the power battery pack 3 is enabled to discharge 20kW at the same time, for a total of 30kW to be charged to the charged vehicle.

[0095] (4) Both the power battery pack 3 and the range-extending power generation device do not meet the discharge conditions, and the range-extending power generation device and the power battery pack 3 stop supplying power to the vehicle to be charged. For example, if the remaining fuel level of the range-extending power generation device is lower than the set threshold and there is no fault, and the remaining power level of the power battery pack 3 is lower than the set threshold and there is no fault, the range-extending power generation device and the power battery pack 3 are controlled to stop supplying power to the vehicle to be charged; for example, if both the range-extending power generation device and the power battery pack 3 are faulty, the range-extending power generation device and the power battery pack 3 are controlled to stop supplying power to the vehicle to be charged.

[0096] The above embodiments are merely examples and do not limit the scope of the present invention. These embodiments can be implemented in various other ways, and various omissions, replacements, and changes can be made without departing from the technical concept of the present invention.

Claims

1. A vehicle-to-vehicle DC charging system for new energy electric vehicles, characterized in that: The system is applied to new energy vehicles, and includes an energy supply module, an energy conversion module, a DC charging and discharging socket, a discharge gun, and a controller. The energy supply module is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller. The energy conversion module is configured to obtain a charging requirement of the charged vehicle after determining that the handshake with the charged vehicle is successful, and report the requirement to the controller; The controller is configured to control the energy supply module to output electrical energy to the energy conversion module according to the charging demand; The energy conversion module is also connected to the DC charging and discharging socket, and is also used to output the energy provided by the energy supply module to the DC charging and discharging socket; The energy supply module includes a power battery pack and a range-extending power generation device, and the range-extending power generation device includes a generator; the energy conversion module includes an AC-DC converter and a voltage regulation module; The AC / DC converter is used to convert the AC power output from the generator into DC power, and the voltage regulator module is used to regulate the voltage of the DC power or the DC power from the power battery pack; The vehicle-to-vehicle DC charging system for the new energy electric vehicle includes the following operating states: the range-extending power generation device supplies power to the vehicle to be charged alone, the power battery pack supplies power to the vehicle to be charged alone, and the range-extending power generation device and the power battery pack supply power to the vehicle to be charged simultaneously; When the range-extended power generation device and the power battery pack simultaneously supply power to the DC charging and discharging socket, the DC power output from the AC / DC converter and the DC power output from the power battery pack are input to the voltage regulating module, which then regulates the voltage and outputs the power through the DC charging and discharging socket.

2. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 1, characterized in that: The power battery pack is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller.

3. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 2, characterized in that: The range-extending power generation device is connected to the controller and the energy conversion module respectively, and is used to provide energy to the energy conversion module under the control of the controller.

4. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 3, characterized in that: The range-extending power generation device includes an engine, which is mechanically coupled to a generator to generate electricity. The output end of the generator is connected to a DC charging and discharging socket and a power battery pack through an energy conversion module.

5. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 4, characterized in that: The energy conversion module includes a discharge relay, When the range-extending power generation device supplies power to the DC charging and discharging socket, the output end of the generator is connected to the DC charging and discharging socket through the AC-DC converter, the voltage regulating module, and the discharge relay in sequence. When the power battery pack supplies power to the DC charge and discharge socket, the output end of the power battery pack is connected to the DC charge and discharge socket through the voltage regulation module and the discharge relay in sequence.

6. A vehicle-to-vehicle DC charging system for a new energy electric vehicle according to claim 5, characterized in that: The energy conversion module further includes an insulation monitoring module for performing insulation monitoring on the output circuit of the voltage regulation module. The insulation monitoring module is connected in parallel with the output end of the discharge relay.

7. A vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 6, characterized in that: The energy conversion module further includes a discharge module for discharging the insulation monitoring voltage, and the discharge module is connected in parallel with the output end of the voltage regulation module.

8. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 5, characterized in that: The energy conversion module further includes a current sensor and a voltage sensor. The current sensor is connected in series to the output end of the voltage regulation module, and the voltage sensor is connected in parallel to the output end of the discharge relay.

9. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 2, characterized in that: The power battery pack includes a battery cell and a relay assembly. The battery cell is connected to a DC charging and discharging socket and an energy conversion module through the relay assembly.

10. A vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 9, characterized in that: The relay assembly includes a battery relay and a fast charging relay. When the range-extending power generation device supplies power to the power battery pack or the power battery pack supplies power to the DC charging and discharging socket, the battery cell is connected to the energy conversion module through the battery relay. When the power battery pack is powered by the DC charge and discharge socket, the battery cells are connected to the DC charge and discharge socket via the battery relay and the fast charge relay.

11. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 9, characterized in that: The power battery pack also includes a BMS battery management subsystem, and the controller communicates with the BMS battery management subsystem and regulates the charging power of the power battery pack.

12. The vehicle-to-vehicle DC charging system for new energy electric vehicles according to claim 5, characterized in that: The output end of the AC / DC converter is connected to the input end of the voltage regulation module through a high-voltage wiring harness and a docking copper plate, and the output end of the power battery pack is connected to the input end of the voltage regulation module through a high-voltage wiring harness and a docking copper plate.

13. A vehicle-to-vehicle DC charging method for new energy electric vehicles, characterized in that: The method is applied to a charging vehicle, wherein the charging vehicle is provided with a DC charging system according to any one of claims 1 to 12, and the method comprises: After successfully shaking hands with the charged vehicle, it receives the charging request sent by the charged vehicle; The output power of the energy supply module is controlled according to the charging demand, so that the energy supply module charges the charged vehicle through the energy conversion module, the DC charging and discharging socket, and the discharge gun in sequence until the preset charging cut-off condition is met and the charging stops.

14. A vehicle-to-vehicle DC charging method for a new energy electric vehicle according to claim 13, characterized in that: The method of controlling the output power of the energy supply module according to the charging demand so that the energy supply module charges the charged vehicle through the energy conversion module, the DC charging and discharging socket, and the discharge gun in sequence includes: Determine whether the power battery pack and range-extending power generation device meet discharge conditions; If the power battery pack and the range-extending power generation device both meet the discharge conditions, controlling the power battery pack and the range-extending power generation device to simultaneously provide energy to the energy conversion module; If the power battery pack meets the discharge condition and the range-extending power generation device does not meet the discharge condition, controlling the power battery pack to provide energy to the energy conversion module; If the range-extending power generation device meets the discharge condition and the power battery pack does not meet the discharge condition, the controller controls the range-extending power generation device to provide energy to the energy conversion module; If the power battery pack and the range-extending power generation device do not meet the discharge conditions, the energy supply module is controlled to stop providing energy to the energy conversion module.

15. The vehicle-to-vehicle DC charging method for a new energy electric vehicle according to claim 13, characterized in that: The charging start time and the discharge amount of the charging vehicle are adjusted by a central control device in the charging vehicle or a mobile terminal connected to the charging vehicle.

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