A charging and discharging control method of a direct current charging and discharging machine of a new energy vehicle

Abstract

The application relates to a charging and discharging control method of a direct-current charging and discharging machine of a new energy vehicle, which comprises a charging process and a discharging process, the charging process comprises a manual selection charging process and an automatic selection charging process, the discharging process comprises a manual selection discharging process and an automatic selection discharging process, when the new energy vehicle is connected with the direct-current charging and discharging machine, the user's selection can call the manual selection charging process and the manual selection discharging process, when the new energy vehicle is connected with the direct-current charging and discharging machine for a period of time and no user operation is performed, the charging and discharging controller detects the battery charge capacity of the new energy vehicle and automatically adjusts the battery according to the detection result, if the battery charge capacity is greater than 80%, the automatic selection discharging process is entered, if the battery charge capacity is less than 20%, the automatic selection charging process is entered, idle electric energy can be recycled, the utilization rate of electric energy is improved, and the service life attenuation caused by long-time non-use of the battery is avoided.

Description

Technical Field

[0001] This invention belongs to the field of improvement technology of DC charging and discharging machines for new energy vehicles, and in particular, it is a charging and discharging control method for DC charging and discharging machines for new energy vehicles. Background Technology

[0002] In recent years, with the continuous development of the new energy vehicle industry, more and more new energy vehicles are equipped with charging and discharging interfaces. However, the most widely used function is still charging, which involves connecting the new energy vehicle to the power grid via a DC charger. The discharging function is used infrequently, and new energy vehicles are not always in use. When a new energy vehicle is idle, a significant portion of its electrical energy remains unused, resulting in energy waste. Furthermore, if the battery is left idle for too long without charging or discharging, its lifespan will be reduced due to natural discharge. Therefore, a charging and discharging control method for DC chargers used in new energy vehicles is needed to increase the lifespan of new energy vehicles while improving their energy utilization rate. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and to provide a charging and discharging control method for a new energy vehicle DC charger and discharger. This method allows the user to connect to the DC charger and discharger at the specified time and select the charging mode, and the charging and discharging controller installed in the DC charger and discharger will automatically adjust the charging or discharging based on the battery charge of the new energy vehicle.

[0004] The technical solution adopted in this invention is:

[0005] A charging and discharging control method for a DC charger and discharger for a new energy vehicle includes a charging process and a discharging process, wherein the discharging process includes a manually selected discharging process and an automatically selected discharging process.

[0006] The automatic selective discharge process includes the following steps:

[0007] (1) Determine whether the insertion time meets the conditions;

[0008] If the conditions are met, proceed to the next step; if the conditions are not met, end the automatic selection discharge process.

[0009] (2) Determine whether the battery state of charge meets the conditions;

[0010] When the conditions are met, proceed to the next step; when the conditions are not met, enter the automatic charging process to charge the battery.

[0011] (3) The battery discharges to the power grid.

[0012] The artificially selected discharge process includes the following steps:

[0013] (1) Determine whether the battery state of charge meets the conditions;

[0014] When the conditions are met, proceed to the next step; when the conditions are not met, the battery discharges to the grid.

[0015] (2) Detect user input;

[0016] Users can choose to discharge the battery to the grid or end the manual discharge process based on their input.

[0017] The charging process includes a manual charging process and an automatic charging process;

[0018] The automatic charging selection process includes the following steps:

[0019] (1) Determine whether the usable power of the DC charger / discharger meets the requirements;

[0020] If the conditions are met, proceed to the next step; if the conditions are not met, end the automatic charging selection process.

[0021] (2) Battery charging.

[0022] The manual charging process includes the following steps: detecting user input; selecting battery charging or ending the manual charging process according to the user input.

[0023] The DC charger / discharger detects whether a new energy vehicle is connected to the DC charger / discharger and whether the user selects a mode.

[0024] When the user selects a charging mode, the charge / discharge controller invokes the manual selection charging process;

[0025] When the user selects a discharge mode, the charge / discharge controller invokes the manual selection discharge process.

[0026] When the user does not input any information, the charge / discharge controller will automatically select either the discharge or charging process.

[0027] The battery discharges into the grid, which includes the following steps:

[0028] The charge / discharge controller controls the closing of the discharge contactor;

[0029] The battery state of charge is detected. When the battery state of charge meets the conditions, the discharge contactor disconnects, and the battery discharge to the grid ends.

[0030] The battery charging process includes the following steps:

[0031] The charge / discharge controller controls the closing of the charging contactor;

[0032] When the battery's state of charge meets the requirements or the charging power exceeds the total usable power of the DC charger, the charging contactor disconnects, and battery charging ends.

[0033] Among them, the condition for the insertion time in step (1) of the automatic discharge process is three hours or more; the condition for the battery state of charge in step (2) is that the battery state of charge is greater than 80%.

[0034] Among them, the condition for the battery state of charge in step (1) of the manual discharge process is that the battery state of charge is less than 20%.

[0035] In the automatic charging process, step (1) involves determining the battery's state of charge. When the battery's state of charge is less than 20%, the automatic charging process begins.

[0036] The advantages and positive effects of this invention are:

[0037] In this invention, when a new energy vehicle is connected to a DC charger for a period of time without user operation, the charge / discharge controller detects the battery charge level and automatically adjusts the battery allocation based on the detection results. If the battery charge level is greater than 80%, it enters discharge mode; if the battery charge level is less than 20%, it enters charging mode. This allows for more flexible allocation of the DC charger's charging capacity, reducing the load on the power grid, recovering and utilizing idle electrical energy, improving energy efficiency, and enabling the battery to continue charging or discharging even when the new energy vehicle is not in use for extended periods, thus preventing battery lifespan degradation caused by prolonged inactivity. The battery charge level is also detected when the user selects a charging or discharging mode to prevent overcharging or over-discharging, further protecting battery lifespan. Attached Figure Description

[0038] Figure 1 This is a flowchart illustrating the present invention;

[0039] Figure 2 This is a circuit connection diagram of the present invention. Detailed Implementation

[0040] The present invention will be further described below with reference to the embodiments. The embodiments described below are illustrative and not limiting, and should not be used to limit the scope of protection of the present invention.

[0041] A charging and discharging control method for a DC charger / discharger for new energy vehicles, such as... Figure 1 , 2As shown, the process includes charging and discharging. In actual use, the new energy vehicle is connected to a DC charger / discharger. The DC charger / discharger is equipped with a charge / discharge controller and a charge / discharge module. The charge / discharge module can connect the new energy vehicle to the power grid. The charge / discharge controller can control the opening and closing of the charging contactor switch KA1 and the discharging contactor switch KA2 in the charge / discharge module to make the charge / discharge module enter the charging mode or the discharging mode, thereby controlling the connection status of the new energy vehicle to the power grid and the power exchange mode.

[0042] When the DC charger / discharger is idle, it is in a state of no user access. In this state, the DC charger / discharger performs routine communication and self-checks. During this time, the DC charger / discharger uploads its internal operating status to the cloud platform in real time for maintenance personnel to conduct routine inspections and checks. "No user access" means that no new energy vehicle charging gun is inserted into the DC charger / discharger's charging gun socket; "user access" means that a new energy vehicle charging gun is inserted into the DC charger / discharger's charging gun socket. The cloud platform can be a mobile client or a data center monitoring platform, allowing users to view the real-time status of each DC charger / discharger.

[0043] When a user connects a new energy vehicle to a DC charger, the charger recognizes the vehicle's connection. The user can operate the charger via a display screen connected to the charger controller. The user can select either charging or discharging mode on the screen to control the charger. In charging mode, the charger charges the new energy vehicle's battery, supplying power from the grid to the battery. In discharging mode, the charger discharges the new energy vehicle's battery, supplying power from the battery back to the grid.

[0044] The innovation of this invention lies in the following: When the DC charger / discharger is working, it is in a user-operated state. After the DC charger / discharger is connected to the new energy vehicle, the user selects the charging mode or discharging mode. When the user selects the charging mode, the charger / discharge controller will call the manual selection of the charging process; when the user selects the discharging mode, the charger / discharge controller will call the manual selection of the discharging process; if the user does not make a selection, that is, if the user does not input any information, the charger / discharge controller will call the automatic selection of the charging process or the automatic selection of the discharging process.

[0045] The working process of this invention includes the following steps:

[0046] (1) The charge / discharge controller obtains the usable power of the DC charge / discharge machine in real time;

[0047] (2) Identify whether a user is using the service;

[0048] When a user is using the device, proceed to the next step; when no user is using the device, proceed to the daily communication self-check state.

[0049] (3) Detect user input;

[0050] When user input is detected, proceed to the corresponding manual charging or discharging process selected by the user; when no user input is received, proceed to the next step.

[0051] (4) Determine whether the insertion time meets the conditions;

[0052] If the insertion time is three hours or more, proceed to the next step; if the condition is not met, end the work process.

[0053] (5) Determine whether the battery state of charge meets the conditions;

[0054] When the battery's state of charge is greater than 80%, proceed to the next step; when the battery's state of charge is less than 20%, enter the automatic selective charging process to charge the battery.

[0055] (6) Entering the battery discharge process;

[0056] The charge / discharge controller closes the discharge contactor, and the battery begins to discharge to the grid. When the battery's state of charge is 0%, the discharge contactor opens, and the battery discharge ends.

[0057] Steps (4) to (6) above constitute the automatic discharge selection process. The automatic charging selection process in step (5) above includes the following steps:

[0058] ① Determine whether the usable power of the DC charger / discharger meets the requirements;

[0059] When the usable power of the DC charger is greater than 0, proceed to the next step; when the usable power of the DC charger is 0, end the automatic selection charging process.

[0060] ② Entering the battery charging process;

[0061] The charge / discharge controller controls the charging contactor to close, and the battery begins to charge. When the battery's state of charge is 100% or the charging power exceeds the total usable power of the DC charger, the charging contactor opens, and the battery charging ends.

[0062] In step (3) above, when the user selects a discharge mode, the manual discharge selection process begins, and the steps are as follows:

[0063] ① Determine the battery's state of charge;

[0064] When the battery's state of charge is less than 20%, proceed to the next step; when the battery's state of charge is greater than 20%, the battery discharges into the grid.

[0065] ② Prompt the user to choose whether to continue discharging, and detect the user's input.

[0066] Enter the battery discharge process based on user input or end the manual discharge process.

[0067] In step (3) above, when the user selects a charging mode, the manual charging selection process begins, and the steps are as follows:

[0068] ① Determine the battery's state of charge;

[0069] When the battery's state of charge is greater than 80%, proceed to the next step; when the battery's state of charge is less than 80%, charge the battery.

[0070] ② Prompt the user to choose whether to continue charging, and detect the user's input.

[0071] The user can either initiate the battery charging process based on their input or end the manual charging process.

[0072] In both the automatic and manual discharge processes described above, the battery discharge process is controlled by the charge / discharge controller to close the discharge contactor, and the battery begins to discharge to the grid. When the battery's state of charge is 0%, the discharge contactor opens, and the battery discharge ends.

[0073] In both the automatic and manual charging processes described above, the battery charging process is initiated by the charge / discharge controller closing the charging contactor. When the battery's state of charge reaches 100% or the charging power exceeds the total usable power of the DC charger, the charging contactor opens, and the battery charging ends.

[0074] In this embodiment, the charge / discharge controller can collect the battery state of charge (SOC) from the battery management system (BMS) of the new energy vehicle. Based on the SOC uploaded by the BMS and the user's selection of charging or discharging mode, it provides prompts to the user to prevent overcharging or over-discharging from damaging the battery. If the new energy vehicle remains connected to the DC charger for more than three hours, the user is assumed to accept automatic power allocation. At this time, the system automatically selects to enter either charging or discharging mode based on the battery SOC and the power that the DC charger can allocate. If the battery SOC does not meet the conditions for entering charging or discharging mode, the process ends.

[0075] The above process, where the connection remains active for more than three hours under automatic dispatch conditions, is merely an example. The duration of this connection can be adjusted according to actual usage needs, ranging from half an hour to twenty-four hours. It can be adjusted based on the location of the DC charger / discharger, the environment, and the load of the connected power grid to reduce grid load and improve energy utilization. This invention can be applied in locations where new energy vehicles are parked for extended periods, such as car rental companies, car dealerships, car-sharing parking lots, or ride-hailing parking lots. It can improve the utilization rate of the electrical energy from these long-term idle vehicles and reduce the load on the local power grid.

[0076] When no new energy vehicle is connected to the DC charger, the charger controller will control the DC charger to enter data communication and self-test mode. In data communication mode, the DC charger uploads its working records and real-time status data to the upper-level cloud platform. In self-test mode, the DC charger checks its own components to determine whether they are working properly.

[0077] In this invention, when a new energy vehicle is connected to a DC charger for a period of time without user operation, the charge / discharge controller detects the battery charge level and automatically adjusts the power allocation based on the detection results. If the battery charge level is greater than 80%, it enters discharge mode; if the battery charge level is less than 20%, it enters charging mode. This allows for more flexible allocation of the DC charger's charging capacity, reducing the load on the power grid, recovering and utilizing idle electrical energy, improving energy efficiency, and enabling the battery to continue charging or discharging even when the new energy vehicle is not in use for extended periods, thus preventing battery lifespan degradation caused by prolonged inactivity. The battery charge level is also detected when the user selects a charging or discharging mode to prevent overcharging or over-discharging, further protecting battery lifespan.

Claims

1. A charging and discharging control method of a direct current charging and discharging machine of a new energy vehicle, characterized in that: The working process comprises the following steps: when the new energy vehicle is connected with the direct current charging and discharging machine, the direct current charging and discharging machine detects whether there is user input, if the user selects the manual selection charging mode, the manual selection charging mode is executed, if the user selects the manual selection discharging mode, the manual selection discharging mode is executed, if no user input is detected, the user has no any selection mode is executed, whether the duration of the new energy vehicle and the direct current charging and discharging machine maintaining the connection state meets the automatic allocation condition is judged, if the automatic allocation condition is not met, the working process is ended, if the duration of the new energy vehicle and the direct current charging and discharging machine maintaining the connection state meets the automatic allocation condition, the state of charge of the battery is judged, if the state of charge of the battery meets the discharging condition, the battery discharges to the power grid, when the state of charge of the battery meets the discharging end condition, the battery discharging is ended, if the state of charge of the battery meets the charging condition and the available power of the direct current charging and discharging machine meets the condition, the battery is charged, when the state of charge of the battery meets the charging end condition or the charging power exceeds the total available power of the direct current charging and discharging machine, the battery charging is ended, the user has no any selection mode is executed when there is no user input, which is used for recycling the idle electric energy, improving the electric energy utilization rate and avoiding the life attenuation caused by long-term non-use of the battery.

2. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to claim 1, characterized in that: The manual selection discharging mode is that whether the state of charge of the battery meets the condition is judged, if the condition is met, the user is prompted whether to continue discharging, if the user selects to continue discharging, the discharging contactor is controlled to be closed, the discharging mode is switched, if the user does not select to continue discharging, the working process is ended; If the condition is not met, the battery discharges to the power grid.

3. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to claim 1, characterized in that: The manual selection charging mode is that the state of charge of the battery is judged, if the state of charge of the battery meets the condition, the user is prompted whether to continue charging, if the user selects to continue charging, the charging contactor is controlled to be closed, the charging mode is switched, if the user does not select to continue charging, the working process is ended; If the condition is not met, the battery is charged.

4. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: When the direct current charging and discharging machine detects that there is no new energy vehicle connected with the direct current charging and discharging machine, the direct current charging and discharging machine will perform daily communication and self-checking, and upload the internal operating conditions to the cloud platform in real time.

5. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The battery discharging end condition refers to that the state of charge of the battery is equal to 0%, and the battery charging end condition refers to that the state of charge of the battery is equal to 100% or the charging power exceeds the total available power of the direct current charging and discharging machine.

6. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The charging condition is that the state of charge of the battery is less than 20%, and the discharging condition is that the state of charge of the battery is greater than 80%.

7. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The available power of the direct current charging and discharging machine meeting the condition refers to that the available power of the direct current charging and discharging machine is greater than 0.

8. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The automatic allocation condition is three hours or more.

9. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The condition in the manual selection discharging mode is that the state of charge of the battery is less than 20%.

10. The charging and discharging control method of the direct current charging and discharging machine of the new energy vehicle according to any one of claims 1-3, characterized in that: The condition in the manual selection charging mode is that the state of charge of the battery is greater than 80%.

Images