A charging and discharging control system and control method

Abstract

The present invention belongs to the field of charge and discharge control technology, and specifically discloses a charge and discharge control system, including: a power supply end; a load end; a charging controller connected to the power supply end, used to draw power from the power supply end and adjust the charging power; a battery pack; an inverter; a BMS battery management system; a temperature monitoring module; a control module, which realizes the charge and discharge control of the battery pack; based on the charge and discharge control module, the present invention also discloses a charge and discharge control method, including obtaining the discharge voltage parameter, remaining power parameter and battery cell temperature parameter of each battery cell in the battery pack; the charging controller responds to different charging modes based on the battery cell temperature threshold to charge the battery cell with different output powers; the control module conducts different charging circuits and discharge circuits based on the discharge voltage parameter and the remaining power parameter. The battery pack of the present invention uses two battery cells that can be charged and discharged separately to alternately discharge the load end, while ensuring that the load is powered on, avoiding floating charge of the battery pack.

Description

Technical Field

[0001] The present invention belongs to the technical field of charge and discharge control, and in particular relates to a charge and discharge control system and a control method. Background Art

[0002] Batteries are a core component in energy storage and emergency power supply. The charge and discharge management strategy for battery packs is particularly important, effectively extending battery life and improving performance and safety. However, during energy storage and emergency power supply, batteries serve as a backup power source. Existing technologies often keep batteries in a floating charge state for extended periods, severely impacting their capacity and service life. Consequently, optimizing battery pack charge and discharge strategies has become a hot topic.

[0003] Chinese patent publication number CN112332514B discloses a battery charge and discharge control system and method, which uses a three-state charger to provide different charging modes according to the state of the battery, namely, charging state, zero current output state and discharge state. In this scheme, whether the battery is a single large-capacity battery or a battery pack composed of multiple batteries, when the second health state does not meet the preset conditions, the battery will stop discharging. This is obviously not applicable to the load end that needs to be always on. If two batteries are selected in parallel, how to control the charging and discharging of the two batteries to avoid floating charging while ensuring that the load is always on is still unclear to those skilled in the art. Therefore, it is necessary to design a new charge and discharge control system and method. Summary of the Invention

[0004] The purpose of the present invention is to overcome the defects in the prior art and provide a charge and discharge control system and a control method.

[0005] A first aspect of the present invention provides a charge and discharge control system, comprising:

[0006] Power supply end;

[0007] load end;

[0008] A charging controller, connected to the power supply end, for drawing power from the power supply end and adjusting the charging power;

[0009] a battery pack connected to the charging controller;

[0010] An inverter, located between the battery pack and the load end, for converting the direct current of the battery pack into alternating current for use by the load end;

[0011] BMS battery management system, connected to the battery pack, for obtaining charge and discharge parameters of the battery pack;

[0012] a display terminal connected to the charging controller and the BMS battery management system, the display terminal comprising: a display control component, the display control component being configured to: control and call a first display indicator for display on the display terminal based on adjustment of the charging power by the charging controller, and control and call a second display indicator for display on the display terminal based on charge and discharge parameters of the battery pack acquired by the BMS battery management system;

[0013] a display indicator state regulating component, configured to control a first display state and a first display value of the first display indicator on the display end according to the magnitude of the charging power, and to control a second display state and a second display value of the second indicator on the display end according to the magnitude of the charge and discharge parameters of the battery pack;

[0014] a continuous state display component connected to the display symbol state control component, the continuous state display component being configured to generate a steady-state interval value representing charging power based on a first display state and a display duration of a first display value, and to generate a charge / discharge curve representing charge / discharge duration based on a second display state and a display duration of a second display value;

[0015] The display recording component is connected to the display symbol state control component and the continuous state display component, and is used to generate a first record table according to the first display state, the first display value and the steady-state interval value; and generate a second record table according to the second display state, the second display value and the charge and discharge curve.

[0016] In a further embodiment, the first display indicator is configured to have a first display position formed according to the charging power, and the first display position is defined to synchronize a clock signal of a clock chip provided at the display end via a synchronization signal to obtain a first display state and a display duration of a first display value;

[0017] The second display indicator is configured to have a second display bit formed according to the charge and discharge parameters of the battery pack, and the second display bit is defined to synchronize the clock signal of the clock chip set at the display end through the synchronization signal to obtain the second display state and the display duration of the second display value.

[0018] A further solution is that the display terminal is further provided with an analysis module, which includes a first analysis unit and a second analysis unit.

[0019] The first analysis unit is configured to retrieve the first record table in real time and obtain a first change trend of a steady-state interval value corresponding to a first display state and a first display value over time, generate a first adjustment signal based on the first change trend, and adjust the charging power of the charge controller to maintain stability using the first adjustment signal;

[0020] The second analysis unit is used to call the second record table in real time, and obtain the second change trend of the charge and discharge curve corresponding to the second display state and the second display value over time, generate a second adjustment signal according to the second change trend, and adjust the charge and discharge parameters of the battery pack through the second adjustment signal to maintain stable charge and discharge efficiency.

[0021] A further solution is that the first change trend includes gradually approaching the upper limit value of the steady-state interval based on the median value of the steady-state interval, and / or gradually approaching the lower limit value of the steady-state interval based on the median value of the steady-state interval;

[0022] The second variation trend includes, based on the standard amplitude and peak value of the charge-discharge curve, a deviation value that deviates from the standard amplitude, and / or an abnormal value that deviates from the peak value.

[0023] A further solution is that the battery pack includes battery cell I and battery cell II, a relay I is provided between battery cell I and the charging controller, a relay III is provided between battery cell I and the load end, a relay II is provided between battery cell II and the charging controller, and a relay IV is provided between battery cell II and the load end.

[0024] A further solution is to include

[0025] A temperature monitoring module, connected to the battery pack, for obtaining temperature parameters of cell I and cell II;

[0026] A control module is connected to the BMS battery management system, the charging controller, and the temperature monitoring module, respectively, and outputs a control signal based on the charge and discharge parameters and the temperature parameter. The charge controller loads the control signal to generate a power control instruction, and the power control instruction is used to control the charging strategy of the battery cell I and the battery cell II; and the control module generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharging circuits;

[0027] The power supply end, charging controller, relay I, and battery cell I are connected to form a first charging circuit, and the power supply end, charging controller, relay II, and battery cell II are connected to form a second charging circuit; the battery cell I, relay III, inverter, and load end are connected to form a first discharge circuit, and the battery cell II, relay IV, inverter, and load end are connected to form a second discharge circuit. On the first charging circuit, there is also a relay V for controlling the connection and disconnection between the battery cell I and the power supply end, and on the first discharge circuit, there is also a relay VI for controlling the connection and disconnection between the battery cell I and the load end; on the second charging circuit, there is also a relay VII for controlling the connection and disconnection between the battery cell II and the power supply end, and on the second discharge circuit, there is also a relay VIII for controlling the connection and disconnection between the battery cell II and the load end.

[0028] A further solution is that the control module includes:

[0029] A threshold setting unit is used to set the discharge cut-off voltage, remaining power threshold, and battery temperature threshold of the battery cell;

[0030] A receiving unit, configured to receive the charge and discharge parameters of the BMS battery management system and the cell temperature parameters of the temperature monitoring module;

[0031] a judgment unit, wherein the judgment unit obtains the parameters received by the receiving unit and outputs a control signal corresponding to the parameters;

[0032] an execution unit, wherein the execution unit generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharging circuits;

[0033] The battery cell temperature threshold includes a first temperature threshold and a second temperature threshold, the judgment unit obtains the temperature parameter of the battery pack to generate a corresponding control signal, and the charging controller generates a multi-level charging mode based on the control signal;

[0034] The remaining power threshold includes a first remaining power threshold and a second remaining power threshold.

[0035] A further solution is that the judgment unit obtains the temperature parameter of the battery cell I. If the temperature parameter is less than a first temperature threshold, the judgment unit outputs a first control signal based on the temperature parameter, and the charging controller obtains the first control signal and loads a first-level charging mode. The first-level charging mode charges the battery cell I based on the first output power of the charging controller; if the temperature parameter is greater than the first temperature threshold and less than a second temperature threshold, the judgment unit outputs a second control signal based on the temperature parameter, and the charging controller obtains the second control signal and loads a second-level charging mode. The second-level charging mode charges the battery cell I based on the second output power of the charging controller; if the temperature parameter is greater than the second temperature threshold, the judgment unit outputs a third control signal based on the temperature parameter, and the charging controller obtains the third control signal and loads a third-level charging mode. The third-level charging mode charges the battery cell I based on the third output power of the charging controller;

[0036] The judgment unit obtains a temperature parameter of the battery cell II. If the temperature parameter is less than a first temperature threshold, the judgment unit outputs a first control signal based on the temperature parameter. The charging controller obtains the first control signal and loads a first-level charging mode. The first-level charging mode charges the battery cell II based on the first output power of the charging controller. If the temperature parameter is greater than the first temperature threshold and less than a second temperature threshold, the judgment unit outputs a second control signal based on the temperature parameter. The charging controller obtains the second control signal and loads a second-level charging mode. The second-level charging mode charges the battery cell II based on the second output power of the charging controller. If the temperature parameter is greater than the second temperature threshold, the judgment unit outputs a third control signal based on the temperature parameter. The charging controller obtains the third control signal and loads a third-level charging mode. The third-level charging mode charges the battery cell II based on the third output power of the charging controller.

[0037] The judgment unit obtains the remaining power parameters of the battery cell I and the battery cell II. If the remaining power parameter of the battery cell I is greater than the remaining power parameter of the battery cell II and is greater than the first remaining threshold, the judgment unit generates a fourth control signal, and the execution unit obtains the fourth control signal to conduct the first discharge circuit and the second charging circuit; if the remaining power parameter of the battery cell II is greater than the remaining power parameter of the battery cell I and is greater than the first remaining threshold, the judgment unit generates a fifth control signal, and the execution unit obtains the fifth control signal to conduct the second discharge circuit and the first charging circuit;

[0038] The judgment unit obtains the discharge voltage parameters of the battery cell I and the battery cell II. If the discharge voltage parameter of the battery cell I is greater than the discharge voltage parameter of the battery cell II and greater than the discharge cut-off voltage, the judgment unit generates a fourth control signal, and the execution unit obtains the fourth control signal to conduct the first discharge circuit and the second charging circuit; if the discharge voltage parameter of the battery cell II is greater than the discharge voltage parameter of the battery cell I and greater than the discharge cut-off voltage, the judgment unit generates a fifth control signal, and the execution unit obtains the fifth control signal to conduct the second discharge circuit and the first charging circuit;

[0039] The judgment unit obtains the remaining power parameters of the battery cell I and the battery cell II. If the remaining power parameter of the battery cell I is greater than the second remaining threshold, the judgment unit generates a sixth control signal, the charging controller obtains the sixth control signal to stop charging, and the execution unit obtains the sixth control signal to disconnect the first charging circuit; if the remaining power parameter of the battery cell II is greater than the second remaining threshold, the judgment unit generates a seventh control signal, the charging controller obtains the seventh control signal to stop charging, and the execution unit obtains the seventh control signal to disconnect the second charging circuit.

[0040] A second aspect of the present invention provides a charge and discharge control method, which uses the above-mentioned charge and discharge control system and includes:

[0041] Based on the adjustment of the charging power by the charging controller, a first display indicator is controlled and called to be displayed on the display end, and based on the charge and discharge parameters of the battery pack obtained by the BMS battery management system, a second display indicator is controlled and called to be displayed on the display end;

[0042] controlling a first display state and a first display value of the first display indicator on the display end according to the magnitude of the charging power, and controlling a second display state and a second display value of the second indicator on the display end according to the magnitude of the charge and discharge parameters of the battery pack;

[0043] generating a steady-state interval value for representing charging power according to the first display state and the display duration of the first display value, and generating a charge / discharge curve for representing charging / discharging duration according to the second display state and the display duration of the second display value;

[0044] Generate a first record table according to the first display state, the first display value and the steady-state interval value; and generate a second record table according to the second display state, the second display value and the charge-discharge curve;

[0045] and obtaining a first change trend of a steady-state interval value corresponding to the first display state and the first display value over time, generating a first adjustment signal according to the first change trend, and adjusting the charging power of the charging controller to maintain stability through the first adjustment signal;

[0046] And obtain a second change trend of the charge and discharge curve corresponding to the second display state and the second display value over time, generate a second adjustment signal according to the second change trend, and adjust the charge and discharge parameters of the battery pack through the second adjustment signal to maintain stable charge and discharge efficiency.

[0047] A further solution is that the charge and discharge control method further includes the following control:

[0048] Obtain the discharge voltage parameters, remaining power parameters, and cell temperature parameters of each cell in the battery pack;

[0049] The charging controller charges the battery cell at different output powers in response to different charging modes based on the battery cell temperature threshold;

[0050] The control module switches on different charging circuits and discharging circuits based on the discharge voltage parameter and the remaining power parameter;

[0051] Among them, when the first charging circuit and the second discharging circuit are connected, if the discharge voltage parameter of the battery cell II is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module disconnects the first charging circuit and the second discharging circuit and connects the second charging circuit and the first charging circuit; when the second charging circuit and the first discharging circuit are connected, if the discharge voltage parameter of the battery cell I is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module disconnects the second charging circuit and the first discharging circuit and connects the first charging circuit and the second charging circuit;

[0052] When the first charging circuit and the second discharging circuit are disconnected and the second charging circuit and the first charging circuit are connected, the relay III is controlled to close, the relay V is disconnected, the relay VI is controlled to close, the relay I is disconnected, the relay IV is disconnected, the relay II is controlled to close, the relay VIII is disconnected, and the relay VII is disconnected;

[0053] When the second charging circuit and the first discharging circuit are disconnected and the first charging circuit and the second charging circuit are connected, the relay IV is controlled to close, the relay VIII is controlled to close, the relay VII is controlled to open, the relay II is controlled to open, the relay III is controlled to open, the relay I is controlled to close, the relay V is controlled to close, and the relay VI is controlled to open.

[0054] Compared with the prior art, the beneficial effect of the present invention is that: the present invention adopts two battery cells that can be charged and discharged separately to alternately discharge the load end, and adopts multiple relays to form a first charging circuit, a second charging circuit, a first discharging circuit, and a second discharging circuit. According to the charging and discharging parameters of battery cell I and battery cell II, a suitable charging circuit can be selected for charging and a suitable discharging circuit can be selected for discharging, ensuring that the two battery cells are charged and discharged one by one.

[0055] The present invention outputs different control signals according to different temperature parameters of the battery cell through the judgment unit. The charging controller generates different charging modes based on different control signals and can adjust the charging power according to the battery cell temperature to ensure charging with the fastest charging efficiency without damaging the battery cell.

[0056] The present invention restricts the on and off of the charging circuit by setting a remaining power threshold. When the remaining power of the battery cell is greater than a preset value, the charging circuit is controlled to be disconnected to avoid damage to the battery cell caused by long-term floating charge.

[0057] The present invention also includes a display terminal. After the display terminal is connected to the charging controller, it can display the output power of the charging controller to the charging cell. Since the BMS battery management system can obtain the charge and discharge parameters of the cell and the battery in real time, the control module conducts different charging circuits and discharge circuits based on the discharge voltage parameter and the remaining power parameter, and selects the appropriate cell for charging and discharging. Therefore, the display terminal can display the charge and discharge parameters of the cell and the battery. In addition, the output power of the charging controller to the charging cell can be adjusted by the analysis module to ensure that the steady-state interval value corresponding to each charging mode remains stable. The remaining power parameter of the charging cell and the discharge voltage of the discharging cell are adjusted according to the changing trend of the charging curve to maintain stable charging and discharging efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The following drawings are merely provided for illustrative purposes only and are not intended to limit the scope of the present invention.

[0059] Figure 1 : Schematic diagram of the connection structure of the present invention;

[0060] Figure 2 : Principle block diagram of the control module of the present invention;

[0061] Figure 3 : Schematic diagram of the display terminal connection structure of the present invention;

[0062] Figure 4 : Flowchart of the control method of the present invention;

[0063] In the figure: 1. Power supply end; 2. Charging controller; 3. Protection resistor; 4. Relay I; 5. Relay II; 6. Relay III; 7. Relay IV; 8. Battery pack; 9. BMS battery management system; 10. Control module; 11. Temperature monitoring module; 12. Relay V; 13. Relay VI; 14. Relay VII; 15. Relay VIII; 16. Inverter; 17. Load end; 18. Threshold setting unit; 19. Receiving unit; 20. Judgment unit; 21. Execution unit; 22. Display end; 23. Display control component; 24. Display symbol status control component; 25. Continuous status display component; 26. Display recording component; 27. Analysis module. DETAILED DESCRIPTION

[0064] In order to make the purpose, technical solution, design method and advantages of the present invention more clear, the present invention is further described in detail below through specific embodiments in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0065] Example 1

[0066] like Figure 1As shown, this embodiment provides a charge and discharge control system, including:

[0067] Power supply end 1, powered by solar panels;

[0068] Load end 17, as an application scenario, can be selected for loads that need to be always on, such as municipal monitoring;

[0069] A charging controller 2 is connected to the power supply terminal 1 and is used to draw power from the power supply terminal 1 and adjust the charging power;

[0070] A battery pack 8 includes a cell I and a cell II, wherein a relay I 4 is provided between the cell I and the charge controller 2, a relay III 6 is provided between the cell I and the load terminal 17, a relay II 5 is provided between the cell II and the charge controller 2, and a relay IV 7 is provided between the cell II and the load terminal 17;

[0071] The inverter 16 is located between the battery pack 8 and the load terminal 17 and is used to convert the DC power of the battery pack 8 into AC power for use by the load terminal 17;

[0072] A BMS battery management system 9 is connected to the battery pack 8 and is used to obtain the charge and discharge parameters of the battery cells I and II, wherein the charge and discharge parameters include the discharge voltage and the remaining power parameters of the battery cells;

[0073] A temperature monitoring module, connected to the battery pack 8, for obtaining temperature parameters of battery cells I and II;

[0074] The control module 10 is connected to the BMS battery management system 9, the charging controller 2 and the temperature monitoring module respectively, and outputs a control signal based on the charging and discharging parameters and the temperature parameters. The charging controller 2 loads the control signal to generate a power control instruction, and the power control instruction is used to control the charging strategy of the battery cell I and the battery cell II; and the control module 10 generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharge circuits; specifically, the power supply end 1, the charging controller 2, the relay I4, and the battery cell I are connected to form a first charging circuit, and the power supply end 1, the charging controller 2, the relay II5, and the battery cell II are connected to form a second charging circuit; the battery cell I, the relay III6, and the reverse The inverter 16 and the load end 17 are turned on to form a first discharge circuit, and the battery cell II, relay IV7, inverter 16, and the load end 17 are turned on to form a second discharge circuit. On the first charging circuit, a relay V12 is further provided for controlling the on-off connection between the battery cell I and the power supply end 1, and on the first discharge circuit, a relay VI13 is further provided for controlling the on-off connection between the battery cell I and the load end 17; on the second charging circuit, a relay VII14 is further provided for controlling the on-off connection between the battery cell II and the power supply end 1, and on the second discharge circuit, a relay VIII15 is further provided for controlling the on-off connection between the battery cell II and the load end 17. In this embodiment, a protective resistor 3 is further connected in series with the charging circuit and the discharging circuit.

[0075] like Figure 2 As shown, in this embodiment, the control module 10 includes:

[0076] The threshold setting unit 18 is used to set the discharge cut-off voltage, remaining power threshold, and battery temperature threshold of the battery cell;

[0077] The receiving unit 19 is used to receive the charge and discharge parameters of the BMS battery management system 9 and the battery cell temperature parameters of the temperature monitoring module 11;

[0078] A judgment unit 20, wherein the judgment unit 20 obtains the parameters received by the receiving unit 19 and outputs a control signal corresponding to the parameters;

[0079] The execution unit 21 generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharging circuits.

[0080] Among them, the battery cell temperature threshold includes a first temperature threshold and a second temperature threshold. The judgment unit 20 obtains the temperature parameters of the battery pack 8 to generate a corresponding control signal. The charging controller 2 generates a multi-stage charging mode based on the control signal. In this embodiment, the first temperature threshold corresponds to the normal temperature range during the battery cell charging process, which is set to 40°C in this embodiment. The second temperature threshold is the reminder temperature during high-power charging, which is 50°C.

[0081] During charging, the judgment unit 20 obtains a temperature parameter of cell I. If the temperature parameter is less than a first temperature threshold, the judgment unit 20 outputs a first control signal based on the temperature parameter. The charge controller 2 obtains the first control signal and applies a level 1 charging mode. The level 1 charging mode charges cell I based on the first output power of the charge controller 2. During this process, the temperature of cell I is within a normal range, and charging can continue at the current charging output power to ensure charging efficiency. If the temperature parameter is greater than the first temperature threshold and less than a second temperature threshold, the judgment unit 20 outputs a second control signal based on the temperature parameter. The charge controller 2 obtains the second control signal and applies a level 2 charging mode. The level 2 charging mode charges cell I based on the second output power of the charge controller 2. During this process, the temperature of cell I is higher than normal. If charging continues at the current charging output power, the temperature will continue to rise, posing a risk of damage to cell I. Therefore, it is necessary to reduce the charging output power to ensure that the temperature of cell I drops to the first temperature threshold. If the temperature parameter is greater than the second temperature threshold, the judgment unit 20 outputs a third control signal based on the temperature parameter. The charging controller 2 receives the third control signal and initiates a three-level charging mode. The three-level charging mode charges cell I based on the third output power of the charging controller 2. During this process, since the temperature parameter is greater than the second temperature threshold, cell I is already in a high-temperature state and charging should be stopped promptly. Therefore, the third output power is 0. Since cells I and II are two parallel cells, when cell I is in the charging state, to avoid the same cell being in both the charging and discharging states, the execution unit 21 of this embodiment controls different relays to open or close, so that when one cell is charging, the other cell is discharging. Therefore, when cell I is discharging, cell II is in the charging state. The judgment unit 20 and the charging controller 2 control the charging of cell II in the same manner as for cell I and will not be further described.

[0082] In the above, the remaining power threshold includes a first remaining power threshold and a second remaining power threshold; wherein, the first remaining power threshold is the minimum remaining power to ensure normal discharge of the battery cell. Theoretically, the SOC is 0 after the battery cell is discharged, but in order to ensure that the battery cell is in a better discharge state and avoid the discharge end voltage being lower than the discharge cut-off voltage, therefore, in this embodiment, the SOC value of the first remaining threshold is greater than 0, and the second remaining threshold is the battery cell full state. Theoretically, the SOC value is 1, but considering factors such as battery cell aging and internal resistance, the SOC of the second remaining threshold in this embodiment is less than 1 and greater than the first remaining threshold. The judgment unit 20 obtains the remaining power parameters of the battery cell I and the battery cell II. If the remaining power parameter of the battery cell I is greater than the remaining power parameter of the battery cell II and is greater than the first remaining threshold value, it means that the battery cell I is more suitable for discharge than the battery cell II. Therefore, the judgment unit 20 generates a fourth control signal, and the execution unit 21 obtains the fourth control signal to turn on the first discharge circuit and the second charging circuit to discharge the battery cell I and charge the battery cell II. If the remaining power parameter of the battery cell II is greater than the remaining power parameter of the battery cell I and is greater than the first remaining threshold value, it means that the battery cell II is more suitable for discharge than the battery cell I. Therefore, the judgment unit 20 generates a fifth control signal, and the execution unit 21 obtains the fifth control signal to turn on the second discharge circuit and the first charging circuit to discharge the battery cell II and charge the battery cell I.

[0083] In the above description, the threshold setting unit 18 also sets a discharge cutoff voltage. During the discharge process, as the discharge progresses, the active material of the battery cell decreases and the electromotive force decreases, causing the discharge voltage at the battery terminal to gradually decrease. When the discharge voltage approaches or is less than the discharge cutoff voltage, the discharge of the discharged battery cell should be stopped. Therefore, it is necessary to monitor the discharge voltage of the battery cell and set the charge and discharge strategy based on different discharge voltages. In this embodiment, the judgment unit 20 obtains the discharge voltage parameters of the battery cell I and the battery cell II. If the discharge voltage parameter of the battery cell I is greater than the discharge voltage parameter of the battery cell II and is greater than the discharge cutoff voltage, it means that the battery cell I is more suitable for discharge than the battery cell II. Therefore, the judgment unit 20 generates a fourth control signal, and the execution unit 21 obtains the fourth control signal to conduct the first discharge circuit and the second charging circuit. If the discharge voltage parameter of the battery cell II is greater than the discharge voltage parameter of the battery cell I and is greater than the discharge cutoff voltage, it means that the battery cell II is more suitable for discharge than the battery cell I. Therefore, the judgment unit 20 generates a fifth control signal, and the execution unit 21 obtains the fifth control signal to conduct the second discharge circuit and the first charging circuit.

[0084] In this embodiment, in order to prevent the power supply end 1 from continuously charging the battery cell so that the battery cell is in a floating charge state, the power of the charged battery cell is also monitored, and the remaining power parameters of the battery cell I and the battery cell II are obtained through the judgment unit 20. If the remaining power parameter of the battery cell I is greater than or equal to the second remaining threshold, the judgment unit 20 generates a sixth control signal, the charging controller 2 obtains the sixth control signal to stop charging, and the execution unit 21 obtains the sixth control signal to disconnect the first charging circuit; if the remaining power parameter of the battery cell II is greater than or equal to the second remaining threshold, the judgment unit 20 generates a seventh control signal, the charging controller 2 obtains the seventh control signal to stop charging, and the execution unit 21 obtains the seventh control signal to disconnect the second charging circuit.

[0085] like Figure 1 and Figure 3 As shown, the charge and discharge control system further includes a display terminal 22 connected to the charge controller 2 and the BMS battery management system 9; the display terminal 22 includes:

[0086] A display control component 23 is configured to: control and call a first display indicator to be displayed on the display terminal 22 based on the adjustment of the charging power by the charging controller 2, and control and call a second display indicator to be displayed on the display terminal 22 based on the charge and discharge parameters of the battery pack 8 obtained by the BMS battery management system 9;

[0087] a display indicator state control component 24 for controlling a first display state and a first display value of the first display indicator on the display terminal 22 according to the magnitude of the charging power, and controlling a second display state and a second display value of the second indicator on the display terminal 22 according to the magnitude of the charge and discharge parameters of the battery pack 8;

[0088] a continuous state display component 25 connected to the display symbol state control component 24, the continuous state display component 25 being configured to generate a steady-state interval value representing the charging power according to the display duration of the first display state and the first display value, and to generate a charge / discharge curve representing the duration of charging / discharging according to the display duration of the second display state and the second display value;

[0089] The display recording component 26 is connected to the display symbol state control component 24 and the continuous state display component 25, and is used to generate a first record table according to the first display state, the first display value and the steady-state interval value; and generate a second record table according to the second display state, the second display value and the charge and discharge curve.

[0090] When the display terminal 22 displays, since the charging controller 2 can respond to the first-level charging mode, the second-level charging mode, and the third-level charging mode to charge the battery cell with different output powers based on the temperature parameter being less than the first temperature threshold, the temperature parameter being greater than the first temperature threshold and less than the second temperature threshold, and the temperature parameter being greater than the second temperature threshold, respectively, after the display terminal 22 is connected to the charging controller 2, the output power of the charging controller 2 to the charging battery cell can be displayed. Specifically, the display control component 23 displays the first display indicator based on the adjustment of the charging power by the charging controller 2, and can also control the display state and display value of the first display symbol through the display symbol state control component 24, wherein the display state is used to display the charging mode, and the display value is used to display the charging power; on this basis, this embodiment generates a steady-state interval value based on the display state and display value of the first display symbol through the continuous state display component 25, and the staff can use the steady-state interval value to judge the degree to which the battery cell is affected by the temperature during the charging process. This embodiment also generates a first record table recording the display state, display value, and steady-state interval through the display record component 26. Since the BMS battery management system 9 can obtain the charge and discharge parameters of battery cells I and II in real time, and in this embodiment, the charge and discharge parameters of battery cells I and II change in real time according to their charge and discharge states, the control module 10 conducts different charging circuits and discharge circuits based on the discharge voltage parameter and the remaining power parameter, and selects the appropriate battery cell for charging and discharging. Therefore, after the display terminal 22 is connected to the BMS battery management system 9, it can display the charge and discharge parameters of battery cells I and II. Specifically, the display control component 23 displays a second display indicator based on the charge and discharge parameters of battery cells I and II obtained by the BMS battery management system 9, and can also control the display state and display value of the second display symbol through the display symbol state control component 24, wherein the display state is used to indicate whether the battery cell is in a charging state or a discharging state, and the display value is used to display the discharge voltage and the remaining power; on this basis, this embodiment generates a charge and discharge curve based on the display state and display value of the second display symbol through the continuous state display component 25. This embodiment also generates a second record table recording the display state, display value, and charge and discharge curve through the display record component 26.

[0091] In the above, the first display indicator is configured to have a first display position formed according to the charging power, and the first display position is defined as synchronizing the clock signal of the clock chip set at the display end 22 through the synchronization signal to obtain the first display state and the display duration of the first display value; the second display indicator is configured to have a second display position formed according to the charging and discharging parameters of the battery pack 8, and the second display position is defined as synchronizing the clock signal of the clock chip set at the display end 22 through the synchronization signal to obtain the second display state and the display duration of the second display value.

[0092] In the above description, the display terminal 22 is further provided with an analysis module 27, which includes a first analysis unit and a second analysis unit. The first analysis unit is configured to access the first record table in real time and obtain a first change trend of the steady-state interval value corresponding to the first display state and the first display value over time, and generate a first adjustment signal based on the first change trend. The first adjustment signal is used to adjust the charging power of the charge controller 2 to maintain stability. The second analysis unit is configured to access the second record table in real time and obtain a second change trend of the charge-discharge curve corresponding to the second display state and the second display value over time. The second adjustment signal is used to adjust the charge and discharge parameters of the battery pack 8 to maintain stable charge and discharge efficiency. The first change trend includes gradually approaching the upper limit of the steady-state interval based on the median value of the steady-state interval, and / or gradually approaching the lower limit of the steady-state interval based on the median value of the steady-state interval. The second change trend includes, based on the standard amplitude and peak value of the charge and discharge curve, deviation values ​​from the standard amplitude and / or abnormal values ​​from the peak value.

[0093] In this embodiment, the first analysis unit of the analysis module 27 analyzes the temporal trend of the steady-state interval value and generates a first adjustment signal to adjust the charging power of the charge controller 2 to ensure stable operation of the charge controller 2. Specifically, the charge controller 2 charges the battery cells at different output powers in response to the first-level charging mode, the second-level charging mode, and the third-level charging mode, respectively, based on whether the temperature parameter is less than the first temperature threshold, the temperature parameter is greater than the first temperature threshold and less than the second temperature threshold, and the temperature parameter is greater than the second temperature threshold. The charge controller 2 adjusts the charging power of the charge controller 2 using the first adjustment signal to ensure that the steady-state interval value corresponding to each charging mode remains stable. The second analysis unit of the analysis module 27 generates a second adjustment signal based on the second trend, and uses the second adjustment signal to adjust the charge and discharge parameters of the battery pack 8 under different charge and discharge conditions. In this embodiment, adjusting the charge and discharge parameters of the battery pack 8 under different charge and discharge conditions includes at least adjusting the remaining power parameter and the discharge voltage parameter. Specifically, during the charge and discharge process, to ensure charge and discharge efficiency, the remaining power parameter of the charging cell and the discharge voltage of the discharging cell can be adjusted according to the changing trend of the charging curve to maintain stable charge and discharge efficiency.

[0094] Example 2

[0095] like Figure 3 As shown, this embodiment provides a charge and discharge control method, which applies the charge and discharge control system provided in Example 1, including:

[0096] Obtaining discharge voltage parameters, remaining capacity parameters, and cell temperature parameters of each cell in the battery pack 8;

[0097] The charging controller 2 responds to the first-level charging mode, the second-level charging mode, and the third-level charging mode to charge the battery cell with different output powers based on the temperature parameter being less than the first temperature threshold, the temperature parameter being greater than the first temperature threshold and less than the second temperature threshold, and the temperature parameter being greater than the second temperature threshold;

[0098] The control module 10 switches on different charging circuits and discharging circuits based on the discharge voltage parameter and the remaining power parameter, and selects appropriate battery cells for charging and discharging.

[0099] The charging controller 2 responds to different charging modes based on the battery cell temperature threshold to charge the battery cell with different output powers, including:

[0100] The judgment unit 20 obtains the temperature parameter of the battery cell I. If the temperature parameter is less than the first temperature threshold, the judgment unit 20 outputs a first control signal based on the temperature parameter, and the charging controller 2 obtains the first control signal and loads the first-level charging mode. The first-level charging mode charges the battery cell I based on the first output power of the charging controller 2; if the temperature parameter is greater than the first temperature threshold and less than the second temperature threshold, the judgment unit 20 outputs a second control signal based on the temperature parameter, and the charging controller 2 obtains the second control signal and loads the second-level charging mode. The second-level charging mode charges the battery cell I based on the second output power of the charging controller 2; if the temperature parameter is greater than the second temperature threshold, the judgment unit 20 outputs a third control signal based on the temperature parameter, and the charging controller 2 obtains the third control signal and loads the third-level charging mode. The third-level charging mode charges the battery cell I based on the third output power of the charging controller 2. Since cell I and cell II are two parallel cells, when cell I is in the charging state, to prevent the same cell from being in both the charging and discharging states, the execution unit 21 of this embodiment controls different relays to open or close, so that when one cell is charging, the other cell is discharging. Therefore, when cell I is discharging, cell II is in the charging state. The judgment unit 20 and the charging controller 2 control the charging of cell II in the same way as for cell I, and will not be repeated here.

[0101] During the process of the control module 10 turning on different charging circuits and discharging circuits, when the first charging circuit and the second discharging circuit are turned on, if the discharge voltage parameter of the battery cell II is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module 10 disconnects the first charging circuit and the second discharging circuit and turns on the second charging circuit and the first charging circuit; when the second charging circuit and the first discharging circuit are turned on, if the discharge voltage parameter of the battery cell I is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module 10 disconnects the second charging circuit and the first discharging circuit and turns on the first charging circuit and the second charging circuit. Specifically, when the first charging circuit and the second discharging circuit are disconnected and the second charging circuit and the first charging circuit are connected, the relay III6 is controlled to be closed, the relay V12 is disconnected, the relay VI13 is closed, the relay I4 is disconnected, the relay IV7 is disconnected, the relay II5 is closed, the relay VIII15 is disconnected, and the relay VII14 is disconnected in sequence; when the second charging circuit and the first discharging circuit are disconnected and the first charging circuit and the second charging circuit are connected, the relay IV7 is controlled to be closed, the relay VIII15 is closed, the relay VII14 is disconnected, the relay II5 is disconnected, the relay III6 is disconnected, the relay I4 is closed, the relay V12 is closed, and the relay VI13 is disconnected.

[0102] On this basis, the charge and discharge control method also includes:

[0103] Based on the adjustment of the charging power by the charging controller 2, the first display indicator is controlled and called to be displayed on the display end, and based on the charge and discharge parameters of the battery pack 8 obtained by the BMS battery management system 9, the second display indicator is controlled and called to be displayed on the display end;

[0104] Controlling a first display state and a first display value of the first display indicator on the display end according to the magnitude of the charging power, and controlling a second display state and a second display value of the second indicator on the display end according to the magnitude of the charge and discharge parameters of the battery pack 8;

[0105] generating a steady-state interval value for representing charging power according to the first display state and the display duration of the first display value, and generating a charge / discharge curve for representing charging / discharging duration according to the second display state and the display duration of the second display value;

[0106] Generate a first record table according to the first display state, the first display value and the steady-state interval value; and generate a second record table according to the second display state, the second display value and the charge-discharge curve;

[0107] and obtaining a first change trend of the steady-state interval value corresponding to the first display state and the first display value over time, generating a first adjustment signal according to the first change trend, and the charging controller 2 adjusting the charging power of the charging controller 2 according to the first adjustment signal so that the steady-state interval value corresponding to each charging mode remains stable;

[0108] And obtain the second change trend of the charge and discharge curve corresponding to the second display state and the second display value over time, and generate a second adjustment signal based on the second change trend. During the charging and discharging process, in order to ensure the charging and discharging efficiency, the remaining power parameters of the charging battery cell and the discharge voltage of the discharging battery cell can be adjusted according to the second adjustment signal to keep the charging and discharging efficiency stable.

[0109] While various embodiments of the present invention have been described above, the above descriptions are intended to be illustrative, non-exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments. The terminology used herein is selected to best explain the principles of the embodiments, their practical applications, or technological improvements in the marketplace, or to enable others skilled in the art to understand the embodiments disclosed herein.

Claims

1. A charge and discharge control system, characterized in that: include: Power supply end; load end; A charging controller, connected to the power supply end, for drawing power from the power supply end and adjusting the charging power; a battery pack connected to the charging controller; An inverter, located between the battery pack and the load end, for converting the direct current of the battery pack into alternating current for use by the load end; BMS battery management system, connected to the battery pack, for obtaining charge and discharge parameters of the battery pack; a temperature monitoring module connected to the battery pack and used to obtain temperature parameters of cell I and cell II; the battery includes cell I and cell II, a relay I is provided between cell I and the charge controller, a relay III is provided between cell I and the load end, a relay II is provided between cell II and the charge controller, and a relay IV is provided between cell II and the load end; A control module is connected to the BMS battery management system, the charging controller, and the temperature monitoring module, respectively, and outputs a control signal based on the charge and discharge parameters and the temperature parameter. The charging controller loads the control signal to generate a power control instruction, and the power control instruction is used to control the charging strategy of the battery cell I and the battery cell II; and the control module generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharging circuits; a display terminal connected to the charging controller and the BMS battery management system, the display terminal comprising: a display control component, the display control component being configured to: control and call a first display indicator for display on the display terminal based on adjustment of the charging power by the charging controller, and control and call a second display indicator for display on the display terminal based on charge and discharge parameters of the battery pack acquired by the BMS battery management system; a display indicator state regulating component, configured to control a first display state and a first display value of the first display indicator on the display end according to the magnitude of the charging power, and to control a second display state and a second display value of the second indicator on the display end according to the magnitude of the charge and discharge parameters of the battery pack; a continuous state display component connected to the display symbol state control component, the continuous state display component being configured to generate a steady-state interval value representing charging power based on a first display state and a display duration of a first display value, and to generate a charge / discharge curve representing charge / discharge duration based on a second display state and a display duration of a second display value; A display recording component, connected to the display symbol state control component and the continuous state display component, for generating a first record table according to the first display state, the first display value and the steady-state interval value; and generating a second record table according to the second display state, the second display value and the charge and discharge curve; The display terminal is further provided with an analysis module, which includes a first analysis unit and a second analysis unit; The first analysis unit is configured to retrieve the first record table in real time and obtain a first change trend of a steady-state interval value corresponding to a first display state and a first display value over time, generate a first adjustment signal based on the first change trend, and adjust the charging power of the charge controller to maintain stability using the first adjustment signal; The second analysis unit is configured to retrieve the second record table in real time and obtain a second change trend of the charge and discharge curve corresponding to the second display state and the second display value over time, generate a second adjustment signal based on the second change trend, and adjust the charge and discharge parameters of the battery pack using the second adjustment signal to maintain stable charge and discharge efficiency; The control module includes: A threshold setting unit is used to set the discharge cut-off voltage, remaining power threshold, and battery temperature threshold of the battery cell; A receiving unit, configured to receive the charge and discharge parameters of the BMS battery management system and the cell temperature parameters of the temperature monitoring module; a judgment unit, wherein the judgment unit obtains the parameters received by the receiving unit and outputs a control signal corresponding to the parameters; an execution unit, wherein the execution unit generates a charge and discharge state control instruction based on the control signal to conduct different charging circuits and discharging circuits; The battery cell temperature threshold includes a first temperature threshold and a second temperature threshold, the judgment unit obtains the temperature parameter of the battery pack to generate a corresponding control signal, and the charging controller generates a multi-level charging mode based on the control signal; The remaining power threshold includes a first remaining power threshold and a second remaining power threshold.

2. The charge and discharge control system according to claim 1, characterized in that: The first display indicator is configured to have a first display bit formed according to the charging power, and the first display bit is defined to synchronize a clock signal of a clock chip provided at the display end with a synchronization signal to obtain a first display state and a display duration of a first display value; The second display indicator is configured to have a second display bit formed according to the charge and discharge parameters of the battery pack, and the second display bit is defined to synchronize the clock signal of the clock chip set at the display end through the synchronization signal to obtain the second display state and the display duration of the second display value.

3. The charge and discharge control system according to claim 2, characterized in that: The first change trend includes gradually approaching the upper limit of the steady-state interval based on the median of the steady-state interval value, and / or gradually approaching the lower limit of the steady-state interval based on the median of the steady-state interval value; The second variation trend includes, based on the standard amplitude and peak value of the charge-discharge curve, a deviation value that deviates from the standard amplitude, and / or an abnormal value that deviates from the peak value.

4. The charge and discharge control system according to claim 1, characterized in that: The power supply end, charging controller, relay I, and battery cell I are connected to form a first charging circuit, and the power supply end, charging controller, relay II, and battery cell II are connected to form a second charging circuit; the battery cell I, relay III, inverter, and load end are connected to form a first discharge circuit, and the battery cell II, relay IV, inverter, and load end are connected to form a second discharge circuit. On the first charging circuit, there is also a relay V for controlling the connection and disconnection between the battery cell I and the power supply end, and on the first discharge circuit, there is also a relay VI for controlling the connection and disconnection between the battery cell I and the load end; on the second charging circuit, there is also a relay VII for controlling the connection and disconnection between the battery cell II and the power supply end, and on the second discharge circuit, there is also a relay VIII for controlling the connection and disconnection between the battery cell II and the load end.

5. A charge and discharge control system according to claim 4, characterized in that: The judgment unit obtains a temperature parameter of the battery cell I. If the temperature parameter is less than a first temperature threshold, the judgment unit outputs a first control signal based on the temperature parameter. The charging controller obtains the first control signal and loads a first-level charging mode. The first-level charging mode charges the battery cell I based on the first output power of the charging controller. If the temperature parameter is greater than the first temperature threshold and less than a second temperature threshold, the judgment unit outputs a second control signal based on the temperature parameter. The charging controller obtains the second control signal and loads a second-level charging mode. The second-level charging mode charges the battery cell I based on the second output power of the charging controller. If the temperature parameter is greater than the second temperature threshold, the judgment unit outputs a third control signal based on the temperature parameter. The charging controller obtains the third control signal and loads a third-level charging mode. The third-level charging mode charges the battery cell I based on the third output power of the charging controller. The judgment unit obtains a temperature parameter of the battery cell II. If the temperature parameter is less than a first temperature threshold, the judgment unit outputs a first control signal based on the temperature parameter. The charging controller obtains the first control signal and loads a first-level charging mode. The first-level charging mode charges the battery cell II based on the first output power of the charging controller. If the temperature parameter is greater than the first temperature threshold and less than a second temperature threshold, the judgment unit outputs a second control signal based on the temperature parameter. The charging controller obtains the second control signal and loads a second-level charging mode. The second-level charging mode charges the battery cell II based on the second output power of the charging controller. If the temperature parameter is greater than the second temperature threshold, the judgment unit outputs a third control signal based on the temperature parameter. The charging controller obtains the third control signal and loads a third-level charging mode. The third-level charging mode charges the battery cell II based on the third output power of the charging controller. The judgment unit obtains the remaining power parameters of the battery cell I and the battery cell II. If the remaining power parameter of the battery cell I is greater than the remaining power parameter of the battery cell II and is greater than the first remaining threshold, the judgment unit generates a fourth control signal, and the execution unit obtains the fourth control signal to conduct the first discharge circuit and the second charging circuit; if the remaining power parameter of the battery cell II is greater than the remaining power parameter of the battery cell I and is greater than the first remaining threshold, the judgment unit generates a fifth control signal, and the execution unit obtains the fifth control signal to conduct the second discharge circuit and the first charging circuit; The judgment unit obtains the discharge voltage parameters of the battery cell I and the battery cell II. If the discharge voltage parameter of the battery cell I is greater than the discharge voltage parameter of the battery cell II and greater than the discharge cut-off voltage, the judgment unit generates a fourth control signal, and the execution unit obtains the fourth control signal to conduct the first discharge circuit and the second charging circuit; if the discharge voltage parameter of the battery cell II is greater than the discharge voltage parameter of the battery cell I and greater than the discharge cut-off voltage, the judgment unit generates a fifth control signal, and the execution unit obtains the fifth control signal to conduct the second discharge circuit and the first charging circuit; The judgment unit obtains the remaining power parameters of the battery cell I and the battery cell II. If the remaining power parameter of the battery cell I is greater than the second remaining threshold, the judgment unit generates a sixth control signal, the charging controller obtains the sixth control signal to stop charging, and the execution unit obtains the sixth control signal to disconnect the first charging circuit; if the remaining power parameter of the battery cell II is greater than the second remaining threshold, the judgment unit generates a seventh control signal, the charging controller obtains the seventh control signal to stop charging, and the execution unit obtains the seventh control signal to disconnect the second charging circuit.

6. A charge and discharge control method, characterized in that: The charge and discharge control system according to any one of claims 1 to 5 comprises: Based on the adjustment of the charging power by the charging controller, a first display indicator is controlled and called to be displayed on the display end, and based on the charge and discharge parameters of the battery pack obtained by the BMS battery management system, a second display indicator is controlled and called to be displayed on the display end; controlling a first display state and a first display value of the first display indicator on the display end according to the magnitude of the charging power, and controlling a second display state and a second display value of the second indicator on the display end according to the magnitude of the charge and discharge parameters of the battery pack; generating a steady-state interval value for representing charging power according to the first display state and the display duration of the first display value, and generating a charge / discharge curve for representing charging / discharging duration according to the second display state and the display duration of the second display value; Generate a first record table according to the first display state, the first display value and the steady-state interval value; generate a second record table according to the second display state, the second display value and the charge-discharge curve; and obtaining a first change trend of a steady-state interval value corresponding to the first display state and the first display value over time, generating a first adjustment signal according to the first change trend, and adjusting the charging power of the charging controller to maintain stability through the first adjustment signal; And obtain a second change trend of the charge and discharge curve corresponding to the second display state and the second display value over time, generate a second adjustment signal according to the second change trend, and adjust the charge and discharge parameters of the battery pack through the second adjustment signal to maintain stable charge and discharge efficiency.

7. A charge and discharge control method according to claim 6, characterized in that: Also includes the following controls: Obtain the discharge voltage parameters, remaining power parameters, and cell temperature parameters of each cell in the battery pack; The charging controller charges the battery cell at different output powers in response to different charging modes based on the battery cell temperature threshold; The control module switches on different charging circuits and discharging circuits based on the discharge voltage parameter and the remaining power parameter; Among them, when the first charging circuit and the second discharging circuit are connected, if the discharge voltage parameter of the battery cell II is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module disconnects the first charging circuit and the second discharging circuit and connects the second charging circuit and the first charging circuit; when the second charging circuit and the first discharging circuit are connected, if the discharge voltage parameter of the battery cell I is less than the discharge cut-off voltage or the remaining power parameter is less than the first remaining threshold, the control module disconnects the second charging circuit and the first discharging circuit and connects the first charging circuit and the second charging circuit; When the first charging circuit and the second discharging circuit are disconnected and the second charging circuit and the first charging circuit are connected, the relay III is controlled to close, the relay V is disconnected, the relay VI is controlled to close, the relay I is disconnected, the relay IV is disconnected, the relay II is controlled to close, the relay VIII is disconnected, and the relay VII is disconnected; When the second charging circuit and the first discharging circuit are disconnected and the first charging circuit and the second charging circuit are connected, the relay IV is controlled to close, the relay VIII is controlled to close, the relay VII is controlled to open, the relay II is controlled to open, the relay III is controlled to open, the relay I is controlled to close, the relay V is controlled to close, and the relay VI is controlled to open.

Images