Multifunctional charging and discharging transfer cabinet

Abstract

The present invention discloses a multifunctional charging and discharging transfer cabinet, which belongs to the technical field of electric vehicle charging and discharging. The multifunctional charging and discharging transfer cabinet includes: a charging and discharging module, including a charging and discharging circuit unit and a measuring unit and a power unit electrically connected thereto. The charging and discharging module is electrically connected to an electric vehicle for charging and discharging the electric vehicle. The charging and discharging module can be optionally connected to another electric vehicle / load. The working state of the charging and discharging module includes: a charging mode, including an AC slow charging mode and a DC fast charging mode; a V2L mode; and a V2V mode. By integrating multiple circuits in the transfer cabinet, a power supply can be connected to realize AC and DC charging and AC slow charging of electric vehicles. Various specifications of charging currents can be simulated to realize vehicle-to-vehicle external load discharge and vehicle-to-vehicle charging and discharging. It has high safety and is convenient for conducting charging and discharging performance tests of electric vehicles.

Description

Technical Field

[0001] The invention belongs to the technical field of electric vehicle charging and discharging, and in particular relates to a multifunctional charging and discharging switching cabinet. Background Art

[0002] Battery electric vehicles (BEV) refer to vehicles that use onboard power as a power source, use motors to drive wheels, and comply with various requirements of road traffic and safety regulations. Types of electric vehicles: pure electric vehicles (BEV), hybrid electric vehicles (HEV), fuel cell vehicles (FCEV). The driving power of the motor comes from onboard rechargeable batteries or other energy storage devices. Most vehicles are directly driven by motors, some vehicles install the motors in the engine compartment, and some vehicles directly use wheels as rotors for four motors.

[0003] For example, CN113492694A proposes an electric vehicle charging and discharging integrated system and an electric vehicle, the system includes a power supply end, a control box and a charging plug; the control box includes: a live wire, a neutral wire and a ground wire connected to the power supply end and the electric plug, a first resistor, a relay, a connection confirmation line and a signal line connected to the power supply end; wherein the first end of the first resistor is connected to the ground wire, the second end is connected to the normally open contact of the relay, and the normally closed contact of the relay is arranged on the connection confirmation line; when the relay is connected to the normally closed contact, the power supply end charges the electric vehicle through the control box; when the relay is connected to the normally open contact, the power supply end discharges to the outside through the control box. The charging function of the electric vehicle to the external electrical appliance discharge function and the electric vehicle to the vehicle discharge function are realized without replacing the vehicle-end plug, thereby improving the detection work efficiency and user satisfaction. However, there is a lack of a switching device for testing the charging and discharging performance of the electric vehicle, protecting or monitoring the charging and discharging circuit, and realizing a switching device or system for vehicle charging, vehicle-to-vehicle charging and discharging, and vehicle-to-load charging and discharging. Summary of the invention

[0004] The purpose of the present invention is to provide a multifunctional charging and discharging switching cabinet to solve the problems in the charging and discharging process of the existing electric vehicles mentioned in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solution: a multifunctional charging and discharging switching cabinet, comprising:

[0006] The charging and discharging module includes a charging and discharging circuit unit and a measuring unit and a power unit electrically connected thereto. The charging and discharging module is electrically connected to an electric vehicle to charge and discharge the electric vehicle. The charging and discharging module can be optionally connected to another electric vehicle / load. The working state of the charging and discharging module includes:

[0007] Charging mode, including AC slow charging mode and DC fast charging mode;

[0008] V2L mode;

[0009] V2V mode;

[0010] The charging and discharging circuit unit includes a CC terminal control circuit with adjustable resistance for AC slow charging mode and an AC charging main circuit;

[0011] The AC charging main circuit includes 4P contactors KM1, KM2, PLC-controlled current transformer A3, and fuses FU1, FU2, and FU3;

[0012] The charging and discharging circuit unit also includes a switching circuit and an insulation resistance simulation circuit for the DC fast charging mode, and switches are provided at the positive and negative poles of the switching circuit.

[0013] The switching cabinet integrates multiple circuits and can be connected to a power source to realize AC and DC charging of the electric vehicle 5, vehicle-to-vehicle charging and discharging, and vehicle-to-external load charging and discharging tests.

[0014] The switch cabinet is also equipped with 4P contactors KM1 and KM2 to disconnect the live wire and the neutral wire to improve the safety of the test. The current transformer A3 is set to detect the three-phase voltage and current, and can be monitored and controlled by PLC.

[0015] The measuring unit includes a three-phase multifunctional ammeter and a dual-channel ammeter.

[0016] The power unit includes a reverse current protection diode, and the DC contactor in the present invention is also a power element.

[0017] Preferably, the CC terminal control circuit includes a plurality of resistors and corresponding control switches for switching the resistance value between the CC terminal and the PE terminal, the switching range is 10 ohms-4650 ohms, and the minimum resolution is 10 ohms.

[0018] The resistance value of the CC terminal control circuit is adjustable, and the resistance value between the CC terminal and the PE terminal can be switched. The switching range is 10 ohms-4650 ohms, and the minimum resolution is 10 ohms.

[0019] Preferably, when the charging and discharging module is in the V2L mode, the charging and discharging module connects a load and the electric vehicle, and the electric vehicle discharges the load through the charging and discharging module.

[0020] Preferably, when the charging and discharging module is in the V2L mode, it is controlled by the corresponding CC terminal and uses the same set of resistors and switches as the AC slow charging mode, that is, the AC charging main circuit.

[0021] Preferably, when the charging and discharging module is in the V2V mode, the charging and discharging module connects the electric vehicle and another vehicle, and the electric vehicle discharges the vehicle through the charging and discharging module.

[0022] Preferably, the charging and discharging circuit unit also includes a CP end control circuit. When the charging and discharging module is in V2L mode, K11 is turned on and K12 is turned on. When the charging and discharging module is in AC slow charging mode, K13 is turned on.

[0023] Preferably, the switching circuit is used to switch between gun A and gun B for charging in the DC fast charging mode, and a DC power meter is provided in the switching circuit, and fuses FU13, FU14, FU3, and FU4 are connected to the DC power meter. The fuses FU13 and FU3 are connected to the power simulator, and the fuses FU14 and FU4 are connected to the battery pack.

[0024] Preferably, the switching circuit is provided with DC contactors QC1, QC2, QC3, QC4, QC5, QC6, QC7, QC8, and only one of QC1, QC3, QC5, QC7 can be closed at the same time.

[0025] Only one of QC1, QC3, QC5, and QC7 can be closed at the same time to control the power supply of gun A or gun B, and the positive and negative polarity contactors will operate at the same time.

[0026] Preferably, the DC positive and negative electrodes in the insulation resistance simulation circuit are provided with connection switches for incorporating resistance to ground.

[0027] The withstand voltage of GK1-GK6 relays is 6KV, and the withstand voltage of high-voltage resistors such as R100 is 2KV.

[0028] Preferably, the charging and discharging module is electrically connected to a main control module, and the main control module is also used for fault alarm and data recording. The main control module is connected to a display module for display and touch control, and the main control module is also connected to a CAN communication module.

[0029] The communication protocol can be selected from CAN 2.0B standard frame, Ethernet TCP / IP, Modbus-TCP, or serial communication.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] This transfer cabinet integrates multiple circuits and can be connected to a power source to realize DC charging and AC slow charging of electric vehicles. It can simulate charging currents of various specifications and realize AC V2L (car to external load discharge) and AC V2V (car to car charging and discharging) charging and discharging transfer, which is convenient for charging and discharging performance tests of electric vehicles.

[0032] The switch cabinet is also equipped with 4P contactors KM1 and KM2 to disconnect the live wire and the neutral wire to improve the safety of the test. The current transformer A3 is set to detect the three-phase voltage and current, and can be monitored and controlled by PLC.

[0033] The resistance value of the CC terminal control circuit is adjustable, and the resistance value between the CC terminal and the PE terminal can be switched. The switching range is 10 ohms-4650 ohms, and the minimum resolution is 10 ohms.

[0034] The device supports remote control and data reading functions, and has AC, DC voltage, current, and electric energy measurement and recording functions, as well as fault alarm. The touch screen can quickly reflect the operating status of the main contactor. In case of a fault, the main control module will immediately alarm through the touch screen. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 is a flow chart of the present invention;

[0036] Figure 2 It is a schematic diagram of the use mode of the charging and discharging module of the present invention;

[0037] Figure 3 This is a schematic diagram of the interior of the charging and discharging module of the present invention;

[0038] Figure 4 This is a schematic diagram of the AC slow charging mode of the present invention;

[0039] Figure 5 It is a circuit diagram of the AC charging main circuit of the present invention;

[0040] Figure 6 This is a CC terminal control schematic diagram of the present invention;

[0041] Figure 7 A circuit diagram of a CC terminal control circuit of the present invention;

[0042] Figure 8 is a circuit diagram of a CP terminal control circuit of the present invention;

[0043] Fig. 9 It is a principle diagram of the V2L mode of the present invention;

[0044] Fig.10 is a circuit diagram of the V2L main circuit of the present invention;

[0045] Fig.11 is a schematic diagram of the V2V mode of the present invention;

[0046] Fig.12 The V2V mode circuit diagram of the present invention;

[0047] Fig.13A circuit diagram of a switching circuit for a DC fast charging mode of the present invention;

[0048] Fig.14 This is a B-gun control circuit diagram of the DC fast charging mode of the present invention;

[0049] Fig.15 This is a circuit diagram for simulating insulation resistance in the DC fast charging mode of the present invention.

[0050] In the figure: 1. Charging and discharging module; 11. Charging and discharging circuit unit; 12. Measuring unit; 13. Power unit; 2. Main control module; 3. Display module; 4. CAN communication module; 5. Electric vehicle; 51. Charging mode; 511. AC slow charging mode; 512. DC fast charging mode; 52. V2L mode; 53. V2V mode; 6. Another electric vehicle / load. DETAILED DESCRIPTION

[0051] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0052] See also Figure 1-13 The present invention provides a technical solution: a multifunctional charging and discharging transfer cabinet, comprising:

[0053] The charging and discharging module 1 includes a charging and discharging circuit unit 11 and a measuring unit 12 and a power unit 13 electrically connected thereto. The charging and discharging module 1 is electrically connected to an electric vehicle 5 for charging and discharging the electric vehicle 5. The charging and discharging module 1 is optionally connected to another electric vehicle / load 6. The working states of the charging and discharging module 1 include:

[0054] Charging mode 51, including AC slow charging mode 511 and DC fast charging mode 512;

[0055] V2L mode 52;

[0056] V2V mode 53;

[0057] The charge and discharge circuit unit 11 includes a CC terminal control circuit with adjustable resistance for the AC slow charge mode 511 and an AC charging main circuit;

[0058] The AC charging main circuit includes 4P contactors KM1 and KM2, PLC-controlled current transformer A3, and fuses FU1, FU2, and FU3;

[0059] The charging and discharging circuit unit 11 also includes a switching circuit for the DC fast charging mode 512 and an insulation resistance simulation circuit. Switches are provided at the positive and negative poles of the switching circuit.

[0060] In this embodiment, the switching cabinet integrates multiple circuits and can be connected to a power source to implement AC and DC charging of the electric vehicle 5, vehicle-to-vehicle charging and discharging, and vehicle-to-external load charging and discharging tests.

[0061] The switch cabinet is also equipped with 4P contactors KM1 and KM2 to disconnect the live wire and the neutral wire to improve the safety of the test. The current transformer A3 is set to detect the three-phase voltage and current, and can be monitored and controlled by PLC.

[0062] The resistance value of the CC terminal control circuit is adjustable, and the resistance value between the CC terminal and the PE terminal can be switched. The switching range is 10 ohms-4650 ohms, and the minimum resolution is 10 ohms.

[0063] This switching cabinet is also equipped with connectors, including 2 63A 5-core sockets, one of which is a three-phase five-wire power output connected to the load, and the other is a three-phase five-wire power output connected to the charging gun, 1 63A three-phase five-wire power input with a wire plug with a 2-meter cable, and 2 serial port connectors, one of which is used for CC and CP end control to connect to the charging gun, and the other is used as a V2V CP connection port.

[0064] L: live wire, N: neutral wire, PE: ground, CC: connection confirmation, CP: control confirmation.

[0065] Specifically, the CC terminal control circuit includes a plurality of resistors and corresponding control switches for switching the resistance value between the CC terminal and the PE terminal. The switching range is 10 ohms to 4650 ohms, and the minimum resolution is 10 ohms.

[0066] In this embodiment, the control switch is closed or opened to switch the resistance value. The specific implementation principle diagram is shown in Figure 6 , by introducing the parallel resistance of S3 in the vehicle plug to judge the semi-connected state of the vehicle interface, the Appendix A of the national standard 18487.1 stipulates the corresponding three-speed current matching resistance R4 and RC, which are not described here, and the commonly used R4 corresponding implementation circuit is complex, with many components, and the corresponding resistance of the circuit is 1.8kΩ, 2.7kΩ, and 3.3kΩ, to judge the connection state of the vehicle and the rated current under the corresponding conditions. The resistance adjustment range here is narrow, and only fixed value adjustment can be achieved. The CC terminal control circuit provided here can realize arbitrary switching of resistance values ​​of 10 ohms-4650 ohms in the actual charging and discharging test of the electric vehicle 5, with a minimum resolution of 10 ohms, which is convenient for switching the test state, and further refines the test of the semi-connected state of the vehicle, and judges the overcurrent capacity of the charging cable by different resistance values.

[0067] The following table shows the corresponding resistance value or state when a control switch in the CC terminal control circuit is disconnected:

[0068]

[0069] Specifically, when the charge and discharge module 1 is in the V2L mode 52 , the charge and discharge module 1 is connected to the load and the electric vehicle 5 , and the electric vehicle 5 discharges to the load through the charge and discharge module 1 .

[0070] In this embodiment, see Fig. 9 Schematic diagram of V2L mode 52, Fig.10 It is a circuit diagram of the V2L main circuit. The main circuit here is the AC charging main circuit. The battery pack of the electric vehicle 5 used for discharge is discharged through the charging gun. At this time, the 4P contactor KM2 is turned on to discharge the load cabinet in the figure.

[0071] Specifically, when the charging and discharging module 1 is in the V2L mode 52, through the corresponding CC terminal control, the same set of resistors and switches, that is, the AC charging main circuit, is used as in the AC slow charging mode 511.

[0072] In this embodiment, when the charging and discharging module 1 is in the V2L mode 52, through the corresponding CC terminal control, the same set of resistors and switches, namely the AC charging main circuit, are used as in the AC slow charging mode 511.

[0073] Specifically, when the charging and discharging module 1 is in the V2V mode 53 , the charging and discharging module 1 connects the electric vehicle 5 and another vehicle, and the electric vehicle 5 discharges the vehicle through the charging and discharging module 1 .

[0074] In this embodiment, see Fig.12 , connect the load end of the transfer cabinet M and the power supply port of the transfer cabinet N correspondingly through the cable, close the KM2 in the transfer cabinet M, and the corresponding battery pack flows to the transfer cabinet N through the charging gun. The KM1 of the transfer cabinet N is closed, and the battery pack of another vehicle is charged through the charging gun.

[0075] Specifically, the charge and discharge circuit unit 11 also includes a CP end control circuit. When the charge and discharge module 1 is in the V2L mode 52, K11 is turned on and K12 is turned on. When the charge and discharge module 1 is in the AC slow charge mode 511, K13 is turned on.

[0076] Specifically, the switching circuit is used to switch between gun A and gun B for charging under the DC fast charging mode 512. A DC power meter is provided in the switching circuit. The DC power meter is connected to fuses FU13, FU14, FU3, and FU4. Fuses FU13 and FU3 are connected to the power simulator, and fuses FU14 and FU4 are connected to the battery pack.

[0077] In this embodiment, see Fig.13 FU3 and FU4 are 800A fuses to protect the circuit.

[0078] Specifically, the switching circuit is provided with DC contactors QC1, QC2, QC3, QC4, QC5, QC6, QC7, and QC8, and only one of QC1, QC3, QC5, and QC7 can be closed at the same time.

[0079] In this embodiment, see Fig.12 , QC: DC contactor; FU: fuse; FL: 600A / 75mv shunt; D1: reverse current diode, QC1, QC3, QC5, QC7 can only be closed one at a time to control the power supply of gun A or gun B, and the positive and negative polarity contactors act at the same time, such as QC1, QC2.

[0080] A / B two gun output, voltage 1000V, current 630A; DC load transfer, voltage 1000V, current 800A.

[0081] See the B gun control circuit diagram of 512 in DC fast charging mode Fig.14 , used to connect electric car 5 DC charging, the B gun control circuit diagram here is the same as the A gun control circuit diagram.

[0082] Specifically, the DC positive and negative electrodes in the insulation resistance simulation circuit are provided with connection switches for incorporating resistance to ground.

[0083] In this embodiment, see Fig.15 P3 shown here is a circuit board, and the insulation resistance simulation circuit is set on the circuit board. The DC positive and negative poles are provided with connection switches to incorporate the ground resistance, which is used to test the protection action of the equipment under different insulation resistances. The GK1-GK6 relay has a withstand voltage of 6KV, and the R100 and other high-voltage resistors have a withstand voltage of 2KV.

[0084] Specifically, the charge and discharge module 1 is electrically connected to the main control module 2 , which is also used for fault alarm and data recording. The main control module 2 is connected to the display module 3 for display and touch control. The main control module 2 is also connected to the CAN communication module 4 .

[0085] In this embodiment, the main control module 2 includes a PLC, and the display module 3 includes an HMI touch screen for display control, which is convenient for initial debugging and on-site status viewing. The corresponding touch screen can also display and adjust the resistance value of the CC terminal control circuit.

[0086] The main control module 2 also has fault alarm and history recording functions. The standard HMI touch screen can quickly reflect the operating status of the main contactor and can immediately alarm in case of fault.

[0087] The CAN communication module 4 here communicates with the operating console using the CAN 2.0B standard frame with a baud rate of 500k. The CAN communication module 4 converts the Modbus-TCP or Modbus-RTU of the PLC into the CAN 2.0B standard frame. The external device controls or reads the transfer cabinet data through the CAN communication module 4.

[0088] The working principle and use process of the present invention are as follows: the working state of the charging and discharging module 1 is in the AC slow charging mode 511, the resistance value of the CC end control circuit is adjustable, and the resistance value between the CC end and the PE end can be switched, the switching range is 10 ohms-4650 ohms, and the minimum resolution is 10 ohms. 4P contactors KM1 and KM2 are also provided to disconnect the live wire and the neutral wire to improve the safety of the test. The current transformer A3 is provided to detect the three-phase voltage and current, and can be monitored and controlled by the PLC; in the DC fast charging mode 512, the DC positive and negative poles in the insulation resistance simulation circuit are provided with a connecting switch to incorporate the ground resistance, and the switching circuit switches the charging A gun and the B gun when switching the DC fast charging mode 512; in the V2L mode 52, when the charging and discharging module 1 is in the V2L mode 52, the charging and discharging module 1 is connected to the load and the electric vehicle 5, and the electric vehicle 5 discharges the load through the charging and discharging module 1; in the V2V mode 53, the charging and discharging module 1 is connected to the electric vehicle 5 and another vehicle, and the electric vehicle 5 discharges the vehicle through the charging and discharging module 1.

[0089] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. Multifunctional charging and discharging transfer cabinet, characterized by: include: The charging and discharging module includes a charging and discharging circuit unit and a measuring unit and a power unit electrically connected thereto. The charging and discharging module is electrically connected to an electric vehicle to charge and discharge the electric vehicle. The charging and discharging module can be optionally connected to another electric vehicle / load. The working state of the charging and discharging module includes: Charging mode, including AC slow charging mode and DC fast charging mode; V2L mode; V2V mode; The charging and discharging circuit unit includes a CC terminal control circuit with adjustable resistance for AC slow charging mode and an AC charging main circuit; The AC charging main circuit includes 4P contactors KM1, KM2, PLC-controlled current transformer A3, and fuses FU1, FU2, and FU3; The charging and discharging circuit unit also includes a switching circuit and an insulation resistance simulation circuit for the DC fast charging mode, and switches are provided at the positive and negative poles of the switching circuit.

2. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The CC terminal control circuit includes a plurality of resistors and corresponding control switches for switching the resistance value between the CC terminal and the PE terminal. The switching range is 10 ohms to 4650 ohms, and the minimum resolution is 10 ohms.

3. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: When the charging and discharging module is in the V2L mode, the charging and discharging module connects a load and the electric vehicle, and the electric vehicle discharges the load through the charging and discharging module.

4. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: When the charging and discharging module is in the V2L mode, it is controlled by the corresponding CC terminal and uses the same set of resistors and switches as the AC slow charging mode, that is, the AC charging main circuit.

5. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: When the charging and discharging module is in the V2V mode, the charging and discharging module connects the electric vehicle and another vehicle, and the electric vehicle discharges the vehicle through the charging and discharging module.

6. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The charge and discharge circuit unit also includes a CP end control circuit. When the charge and discharge module is in V2L mode, K11 is turned on and K12 is turned on. When the charge and discharge module is in AC slow charging mode, K13 is turned on.

7. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The switching circuit is used to switch between gun A and gun B for charging in the DC fast charging mode. A DC power meter is provided in the switching circuit. The DC power meter is connected to fuses FU13, FU14, FU3, and FU4. The fuses FU13 and FU3 are connected to the power simulator, and the fuses FU14 and FU4 are connected to the battery pack.

8. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The switching circuit is provided with DC contactors QC1, QC2, QC3, QC4, QC5, QC6, QC7, QC8, and only one of QC1, QC3, QC5, QC7 can be closed at the same time.

9. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The DC positive and negative electrodes in the insulation resistance simulation circuit are provided with connection switches for incorporating resistance to ground.

10. The multifunctional charging and discharging switching cabinet according to claim 1 is characterized in that: The charging and discharging module is electrically connected to a main control module, and the main control module is also used for fault alarm and data recording. The main control module is connected to a display module for display and touch control, and the main control module is also connected to a CAN communication module.

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