A V2G DC charging and discharging facility inspection system and discharging method

Abstract

The present invention provides a V2G DC charging and discharging facility inspection device and a discharging method. Based on at least one V2G charger installed in a single electric vehicle charging station, it at least includes: a control module, a battery voltage module, and a relay contactor; the battery voltage module is used to simulate the power supply voltage output of the battery during the charger startup process; the relay contactor is used to control the opening and closing of each circuit switch; the control module is used for the switching of communication ports and protocol control between the devices connected to the charging input interface and the devices connected to the charging output interface, and performs discharging control for an internal small loop composed of the power grid, the charger, the V2G charging and discharging facility inspection device, the V2G charger, and the power grid in sequence.

Description

Technical Field

[0001] The present invention belongs to the technical field of charging and discharging test of chargers, and particularly relates to a V2G DC charging and discharging facility inspection system and a discharging method. Background Art

[0002] The statements in this part only provide background technical information related to the present invention, and do not necessarily constitute prior art.

[0003] V2G is an abbreviation for Vehicle-to-grid. V2G describes the relationship between electric vehicles and the power grid. When an electric vehicle is not in use, the electric energy of the on-vehicle battery is sold to the power grid system. If the on-vehicle battery needs to be charged, the current flows from the power grid to the vehicle. The charging and discharging facility refers to a charging device with V2G function.

[0004] At present, new energy vehicles are developing towards the direction of "electrification, networking, and intelligence". How to make the charging network more intelligent is a new development model of charging piles that will be spawned by new infrastructure. The V2G technology is exactly the cutting-edge technology in this direction, and V2G charging and discharging facilities will be gradually deployed. Therefore, the layout of inspection devices is also inevitable. On the one hand, it solves the verification problem that V2G charging and discharging facilities must use detection devices and carry heavy loads to perform full-power charging. At the same time, the heavy loads carried have a huge energy consumption problem, increasing the cost consumption. On the other hand, it solves the problem that V2G charging and discharging facilities must require a vehicle or an on-vehicle battery to discharge.

[0005] Through the above introduction, the inspection of DC chargers must carry detection devices and heavy loads or large inspection vehicles to perform full-power charging verification. At the same time, the heavy loads carried have a huge energy consumption problem, increasing the cost consumption. The inspection of V2G charging and discharging facilities must require a vehicle or a battery to discharge, increasing the operation and maintenance difficulty and resulting in a long-term state of less maintenance or even no maintenance.

[0006] Therefore, the technical problems existing in the prior art mainly include:

[0007] (1) For the in-vehicle charging and discharging system based on V2G technology, batteries must be carried during on-site operation and maintenance, which is heavy and unsafe and not suitable for on-site charging and discharging operation and maintenance.

[0008] (2) For the existing non-vehicle-mounted charger detection device of electric vehicles, the load method uses the AC output by the controlled inverter to complete grid connection with the AC power grid, reducing the electric energy consumed during detection. The volume of the high-power inverter is relatively large. On the one hand, on-site installation is not practical and it is ineffective for operation and maintenance.

[0009] The above devices used on-site need to carry heavy loads, causing transportation difficulties. Summary of the Invention

[0010] To overcome the deficiencies of the above-mentioned existing technologies, the present invention provides an inspection device for V2G DC charging and discharging facilities, which can efficiently complete V2G DC charging and discharging and is convenient to use.

[0011] To achieve the above object, one or more embodiments of the present invention provide the following technical solutions:

[0012] In the first aspect, an inspection system for V2G DC charging and discharging facilities is disclosed, including a charger and an inspection device for V2G DC charging and discharging facilities. At least one of the chargers is a V2G charger. The inspection device for V2G DC charging and discharging facilities at least includes:

[0013] A control module, a battery voltage module, and a relay contactor;

[0014] The battery voltage module is used to simulate the power supply voltage output of the battery during the startup process of the charger.

[0015] The relay contactor is used to control the opening and closing of each circuit switch.

[0016] The control module is used for the switching of the communication ports and protocol control between the devices connected to the charging input interface and the devices connected to the charging output interface.

[0017] In a further technical solution, the system performs discharge control based on the control module, and the discharge control sequence is: an internal small cycle composed of the power grid, the charger, the inspection device for V2G DC charging and discharging facilities, the V2G charger, and the power grid in sequence.

[0018] In a further technical solution, the charging input interface is used to connect the charging gun of the charger, and the charging output interface is used to connect a resistive load, a vehicle, or the charging gun of the V2G charger.

[0019] In a further technical solution, the control module is built-in with a wireless communication module, and is connected to a mobile terminal through the wireless communication module for display operations, and is connected to a background server through the wireless communication module for information interaction.

[0020] In a further technical solution, both the charging input interface and the charging output interface are charging sockets.

[0021] In a further technical solution, it further includes: a battery module. The battery module is the power supply module of the entire device, and charges the battery through the charger interface, or also charges the battery through AC220V.

[0022] In a further technical solution, the two input ends of the control module are respectively connected to the charging sockets of the charging input interface, and the two output ends of the control module are respectively connected to the charging sockets of the charging output interface.

[0023] Preferably, a first switch is connected between two input terminals of the control module, a second switch is connected between two output terminals of the control module, a third switch is connected between the positive input terminal and the positive output terminal of the control module, and a fourth switch is connected between the negative input terminal and the negative output terminal of the control module;

[0024] The four switches are used for switching the communication port protocol to realize the protocol switching from the start of the charger to the load connection mode.

[0025] In a second aspect, a method for inspecting a V2G DC charging and discharging facility inspection system is disclosed, including:

[0026] Start the charger, perform program handshake interaction with the V2G charging and discharging facility inspection device, the charger closes the contactor for insulation detection and discharge, and perform the insulation detection of the charger;

[0027] After the insulation detection of the charger is completed, when the output voltage of the charger reaches the required voltage, start the V2G charger, start detecting the battery voltage, the charger closes the contactor, and starts discharging.

[0028] A further technical solution further includes: the V2G charging and discharging facility inspection device outputs the battery voltage. After the charger detects the battery voltage, it boosts the voltage to the set value of the battery voltage and then closes the contactor to output the voltage. The V2G charging and discharging facility inspection device disconnects the third and fourth switches and exits the battery voltage output;

[0029] When the output voltage of the charger reaches the required voltage and the insulation detection of the V2G charger is completed and the battery voltage starts to be detected, close the first and second switches to output.

[0030] A further technical solution is that when the discharging is completed, the V2G charging and discharging facility inspection device first controls the V2G charger to stop and disconnects the first and second switches. The V2G charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock.

[0031] A further technical solution is that while the V2G charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock, the V2G charging and discharging facility inspection device controls the charger to stop. The charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock.

[0032] The above one or more technical solutions have the following beneficial effects:

[0033] The present invention discloses a V2G DC charging and discharging facility inspection device and a discharging strategy. The above solution is arranged based on the V2G charging and discharging facilities. For example, at least one V2G charger is installed in a single electric vehicle charging station. The V2G DC charging and discharging facility inspection device and the discharging strategy of the present invention can realize an internal small cycle of power grid - charger - V2G charging and discharging facility inspection device - V2G charger - power grid.

[0034] On the one hand, for the inspection of the present invention, only by carrying the V2G DC charging and discharging facility inspection device can the verification of the full-power charging of the charging and discharging facilities be carried out, and the loss during the test process is extremely low. On the other hand, for the discharging test of the V2G charging and discharging facilities during the inspection, it is not necessary to carry a vehicle or a battery for discharging. Moreover, only partial energy consumption due to efficiency and line loss exists during the charging and discharging process, without high-power loss, which can greatly reduce the energy consumption during the on-site test, reduce the inspection test cost. At the same time, because it is a local small cycle of the power grid, it will not affect the power quality of the entire power grid.

[0035] The use of the V2G DC charging and discharging facility inspection device and the discharging strategy of the present invention will reduce the burden of maintenance personnel carrying high-power loads, greatly reduce power loss, thereby improving the operation and maintenance detection efficiency of charging and discharging facilities such as V2G, reducing the operation and maintenance difficulty, reducing the cost, and continuously improving the quality level of the charging and discharging facilities.

[0036] Advantages of additional aspects of the present invention will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The specification drawings constituting a part of the present invention are used to provide a further understanding of the present invention. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention.

[0038] Figure 1 It is a schematic diagram of the connection for the use of the device in the embodiment of the present invention;

[0039] Figure 2 It is a schematic diagram of the structure of the device in the embodiment of the present invention;

[0040] Figure 3 It is a state diagram of the process for controlling the V2G load of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0041] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present invention. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0042] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present invention.

[0043] In the case of no conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0044] Embodiment 1

[0045] See the appendix Figure 1 As shown, this embodiment discloses a V2G DC charging and discharging facility inspection system, including a V2G charging and discharging facility inspection device. The V2G charging and discharging facility inspection device can be connected to a charger (including a general charger and a charger with V2G function) to start charging. On the one hand, it can be directly connected to a resistive load to start the current, or it can be directly connected to an electric vehicle to view the entire charging process and messages. On the other hand, it can be directly connected to a V2G charger to start the current and feedback the energy to the power grid, realizing a small cycle within the power grid, that is, realizing the small cycle of power grid-charger-V2G charging and discharging facility inspection device-V2G charger-power grid. Without increasing the burden on the power grid and at the same time greatly reducing the load loss.

[0046] See the appendix Figure 2 As shown, the specific V2G charging and discharging facility inspection device is composed of charging sockets CZ1, CZ2, a 765 control module, a battery voltage module, a battery module, and a relay contactor.

[0047] In a specific example, the charging socket CZ1 is a charging input interface for connecting the charging gun of the charger; the charging socket CZ2 is a charging output interface for connecting a resistive load, a vehicle, or the charging gun of a V2G charger.

[0048] The 765 control module is the control center of the V2G charging and discharging facility inspection device, responsible for the switching of communication ports and protocol control. The switching of communication ports and protocol control is mainly to be compatible with traditional detection methods to realize charger-V2G charging and discharging facility inspection device-load, and the load can be a resistive load or a vehicle. It is built-in with Bluetooth and 4G, and can be connected to a mobile phone WeChat mini-program through Bluetooth for display operations, setting and displaying charging and discharging parameters such as required voltage, required current, discharge current, etc. It controls the simulation of chargers, the guiding faults of V2G chargers, etc. It conducts information interaction with the background server through 4G, and the information interaction content includes: test results, including the working status of the charger and the working status of the V2G charger, the fault simulation situation, etc.

[0049] The battery voltage module simulates the battery power supply voltage output during the start-up process of the charger.

[0050] The battery module is the power supply module of the entire device, which can charge the battery through the A+A- interface of the charger, or can also charge the battery through AC220V.

[0051] The relay contactor is the device action control switch, responsible for turning on and off each switch.

[0052] Among them, the 765 control module loads the communication port and protocol control strategy for switching, specifically as follows:

[0053] 1. Connect the charging gun of the charger to the socket CZ1, turn on the mobile phone Bluetooth and connect to the mobile phone WeChat mini-program for display operation. Select the relevant charger program (GB 15 or GB 11). When the load is a general resistive load, connect the charging gun to CZ2, and the program controls DO1 to close and DO2, DO3, DO4 to open, realizing the switching of the protocol port, and achieving the purpose of the V2G charging and discharging facility inspection device starting the charger to directly connect to the resistive load. The CAN1 port calls the relevant GB 15 or GB 11 protocol.

[0054] 2. Connect the charging gun of the charger to the socket CZ1, turn on the mobile phone Bluetooth and connect to the mobile phone WeChat mini-program for display operation. Select the relevant charger program (GB 15 or GB 11). When the load is a protocol load, connect the charging gun to CZ2, and the program controls DO1 and DO2 to close and DO3, DO4 to open, realizing the switching of the protocol port, and achieving the purpose of the V2G charging and discharging facility inspection device starting the charger with protocol control to connect to the resistive load. The CAN1 port calls the relevant GB 15 or vehicle protocol, and the CAN2 port calls the relevant load protocol.

[0055] 3. Connect the charging gun of the charger to the socket CZ1, turn on the mobile phone Bluetooth and connect to the mobile phone WeChat mini-program for display operation. Select the relevant charger program (GB 15 or GB 11). When the load is a V2G load, connect the V2G charger's charging gun to CZ2, and the program controls DO1 to close and DO2 to close, and DO3, DO4 to open, realizing the switching of the protocol port, and achieving the purpose of the V2G charging and discharging facility inspection device starting the charger, and the protocol control starts the V2G charger to further realize the small cycle inside the power grid - charger - V2G charging and discharging facility inspection device - V2G charger - power grid. The CAN1 port calls the relevant GB 15 or vehicle protocol, and the CAN2 port calls the V2G protocol.

[0056] 4. The charging gun of the charger is connected to the socket CZ1. Turn on the Bluetooth of the mobile phone and connect it to the WeChat mini-program of the mobile phone for display operation. Select the relevant charger program (GB 15 or GB 11). When the load is a vehicle, use a double-headed charging gun to connect one end to CZ2 and the other end to the vehicle socket. The program controls DO3 and DO4 to close, and DO1 and DO2 to disconnect, realizing the switching of the protocol ports and achieving the purpose of the V2G charging and discharging facility inspection device to monitor the vehicle charging process. The CAN1 port program is not called, and the CAN2 port records and collects charging messages.

[0057] Among them, DO1, DO2, DO3, and DO4 are responsible for the switching of the communication port protocol, realizing the protocol switching from the charger startup to the load connection method. Among them, K1K2 is responsible for the control of the main circuit output, and k3K4 is responsible for the battery output control of the battery voltage simulation during the charger startup process.

[0058] In the electric vehicle charging station, V2G charging and discharging facilities are arranged. For example, at least one V2G charger is installed in a single electric vehicle charging station, which can not only charge electric vehicles but also make the V2G charger act as a load for charger detection through the V2G charging and discharging facility inspection device. Two or more V2G chargers can also perform mutual charging and discharging detection.

[0059] Embodiment 2

[0060] See the appendix Figure 3 As shown, the purpose of this embodiment is to provide a small internal circulation discharge control strategy for the power grid - charger - V2G charging and discharging facility inspection device - V2G charger - power grid:

[0061] Step 1: The charging gun of the charger is connected to the charging socket CZ1 of the V2G charging and discharging facility inspection device, and the charging gun of the V2G charger is connected to the charging socket CZ2 of the V2G charging and discharging facility inspection device. Turn on the Bluetooth of the mobile phone and connect it to the WeChat mini-program of the mobile phone for display operation settings. Select the relevant charger program (GB 15 or GB 11), set parameters such as the required voltage and current, and click to start charging. The V2G charging and discharging facility inspection device program controls DO1 to close, DO2 to close, and DO3 and DO4 to disconnect. The CAN1 port calls the relevant GB 15 or vehicle protocol, and the CAN2 port calls the V2G protocol.

[0062] To achieve the small internal circulation of the power grid - charger - V2G charging and discharging facility inspection device - V2G charger - power grid. First, it is necessary to realize the switching of the protocol ports, so that the V2G charging and discharging facility inspection device can call the charger protocol port to start the charger, and call the V2G charger protocol port to realize the startup control of the V2G charger.

[0063] Step 2: Start the charger. The charger locks the gun and closes the auxiliary power supply, and conducts a program handshake interaction with the V2G charging and discharging facility inspection device. The charger closes the contactor for insulation detection and discharge, and the program configuration interaction disconnects the contactor. The V2G charging and discharging facility inspection device closes K3 and K4 to output the battery voltage. After the charger detects the battery voltage, it boosts the voltage to 10V lower than the battery voltage and then closes the contactor to output the voltage. The V2G charging and discharging facility inspection device disconnects K3 and K4 and exits the battery voltage output. Boosting the voltage is used to simulate the vehicle battery voltage, start the charger, and achieve the pre-charging process of the charger.

[0064] It should be noted that when the V2G charging and discharging facility inspection device closes K3 and K4 to output the battery voltage, after the charger detects the battery voltage, when the charger output voltage reaches the required voltage and the V2G charger insulation detection is completed and starts to detect the battery voltage, K1 and K2 are closed for output.

[0065] The main purpose of the four switches is to realize the switching of protocol ports, aiming to be compatible with the line connections of charger-device-load (the load forms are resistive load, vehicle, V2G charger).

[0066] Step 3: When the charger output voltage reaches the required voltage, the V2G charging and discharging facility inspection device prompts to start the V2G charger. The V2G charger locks the gun and closes the auxiliary power supply, and conducts a program handshake interaction with the V2G charging and discharging facility inspection device. The V2G charger closes the contactor for insulation detection and discharge, and the program configuration interaction disconnects the contactor. When starting to detect the battery voltage, the V2G charging and discharging facility inspection device closes K1 and K2 for output. The V2G charger closes the contactor and starts discharging.

[0067] Step 4: When the discharging is completed, the V2G charging and discharging facility inspection device first controls the V2G charger to stop and disconnects K1 and K2. The V2G charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock.

[0068] Step 5: While the V2G charger stops output and disconnects the contactor, the V2G charging and discharging facility inspection device controls the charger to stop. The charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock.

[0069] Step 6: The V2G charging and discharging facility inspection device restores the initial settings, completes the discharging process from the charger to the V2G charging and discharging facility inspection device and then to the V2G charger, and realizes the internal small cycle of power grid-charger-V2G charging and discharging facility inspection device-V2G charger-power grid.

[0070] There is no high-power loss during this discharge process. Only some energy is consumed due to efficiency and line loss, etc., which can greatly reduce the energy consumption during on-site testing and lower the testing cost. At the same time, because it is a small local loop of the power grid, it will not affect the power quality of the entire power grid.

[0071] Although the specific implementation manners of the present invention are described above in conjunction with the accompanying drawings, it is not a limitation to the protection scope of the present invention. Those skilled in the art should understand that based on the technical solutions of the present invention, various modifications or deformations that can be made by those skilled in the art without creative efforts are still within the protection scope of the present invention.

Claims

1. A V2G DC charging and discharging facility inspection device, characterized in that, Based on at least one V2G charger installed at a single electric vehicle charging station, it includes at least: A control module, a battery voltage module, and a relay contactor; The battery voltage module is used to simulate the power supply voltage output of the battery during the startup process of the charger; The relay contactor is used to control the opening and closing of each switch; The control module is used for the switching of communication ports and protocol control between the devices connected to the charging input interface and the devices connected to the charging output interface; The device performs discharge control based on the control module, and the discharge control sequence is: an internal small cycle composed of the power grid, the charger, the V2G charging and discharging facility inspection device, the V2G charger, and the power grid in sequence.

2. The inspection device for a V2G DC charging and discharging facility according to claim 1, wherein The charging input interface is used to connect the charging gun of the charger, and the charging output interface is used to connect a resistive load, a vehicle, or the charging gun of the V2G charger.

3. The inspection device for V2G DC charging and discharging facilities according to claim 1, characterized in that, The control module is built-in with a wireless communication module, which is connected to a mobile terminal through the wireless communication module for display operations and connected to a background server through the wireless communication module for information interaction.

4. The inspection device for V2G DC charging and discharging facilities according to claim 1, characterized in that, Both the charging input interface and the charging output interface are charging sockets.

5. The inspection device for V2G DC charging and discharging facilities according to claim 1, characterized in that it further It includes: A battery module, which is the power supply module of the entire device, charges the battery through the charger interface, or also charges the battery through AC220V.

6. The inspection device for V2G DC charging and discharging facilities according to claim 1, characterized in that, Two input terminals of the control module are respectively connected to the charging socket of the charging input interface, and two output terminals of the control module are respectively connected to the charging socket of the charging output interface.

7. The inspection device for V2G DC charging and discharging facilities according to claim 1, characterized in that, A first switch is connected between the two input terminals of the control module, a second switch is connected between the two output terminals of the control module, a third switch is connected between the positive input terminal and the positive output terminal of the control module, and a fourth switch is connected between the negative input terminal and the negative output terminal of the control module.

8. The inspection device for V2G DC charging and discharging facilities according to claim 7, characterized in that, The four switches are used for the switching of communication port protocols to achieve the protocol switching from the startup of the charger to the load connection mode.

9. The discharging method of a V2G DC charging and discharging facility inspection device according to any one of claims 1-8, characterized in that It includes: Start the charger, perform program handshake interaction with the V2G charging and discharging facility inspection device, the charger closes the contactor for insulation detection and discharge, and perform the insulation detection of the charger; After the insulation detection of the charger is completed, when the output voltage of the charger reaches the required voltage, start the V2G charger, start to detect the battery voltage, the charger closes the contactor, and starts to discharge.

10. The discharging method of an inspection device for V2G DC charging and discharging facilities as described in claim 9, characterized in that it further It includes: The V2G charging and discharging facility inspection device outputs the battery voltage. After the charger detects the battery voltage, it boosts the voltage to the set value of the battery voltage and then closes the contactor to output the voltage. The V2G charging and discharging facility inspection device disconnects the third and fourth switches and exits the battery voltage output; When the output voltage of the charger reaches the required voltage and the insulation detection of the V2G charger is completed and starts to detect the battery voltage, close the first and second switches to output.

11. The discharging method of a V2G DC charging and discharging facility inspection device according to claim 9, characterized in that, When the discharge is completed, the V2G charging and discharging facility inspection device first controls the V2G charger to stop and disconnects the first and second switches. The V2G charger stops output, disconnects the contactor, discharges, and disconnects the auxiliary power supply to unlock the electronic lock.

12. The discharging method of an inspection device for V2G DC charging and discharging facilities according to claim 9, characterized in that, When the V2G charger stops output, disconnects the contactor, discharges, and unlocks the electronic lock by disconnecting the auxiliary power supply, the V2G charging and discharging facility inspection device controls the charger to shut down. The V2G charger stops output, disconnects the contactor, discharges, and unlocks the electronic lock by disconnecting the auxiliary power supply.

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