Battery changing cabinet charging method and system based on direct current bus

Abstract

The invention provides a method and a system for charging a battery changing cabinet based on a direct-current bus in the technical field of battery changing cabinets. The method comprises the following steps: S1, setting a battery changing idle period, a battery changing peak period, an SOC upper limit threshold value, an SOC interval, a quantity threshold value, a first charging current and a second charging current; s2, when the timestamp is in a battery replacement idle period, the ACDC power supply module transmits electric energy to the DCDC power supply module, and the battery is charged based on the first charging current; s3, when the timestamp is in a battery replacement peak period, selecting a high-priority battery needing to be charged and a low-priority battery needing to be discharged, and connecting the DCDC power supply modules in parallel; and S4, the battery replacement cabinet transmits electric energy to the DCDC power supply module through the ACDC power supply module and the low-priority battery, and charges the high-priority battery based on the second charging current. The method has the advantages that the battery charging efficiency and the adaptive capacity to power grid fluctuation are greatly improved, and centralized and efficient management and energy scheduling of the batteries are achieved.

Description

Technical Field

[0001] This invention relates to the field of battery swapping cabinet technology, and in particular to a battery swapping cabinet charging method and system based on a DC bus. Background Technology

[0002] Two-wheeled electric vehicles have become an important tool for short-distance urban travel due to their convenience and economy, widely used in scenarios such as food delivery, express delivery, and personal daily commuting. However, traditional charging methods have several significant drawbacks: the charging cycle is too long, generally requiring 4-8 hours, severely limiting the work efficiency and order-taking time of delivery riders during peak delivery periods; at the same time, with the rapid increase in the number of electric vehicles, decentralized charging modes have also brought many safety hazards, such as users privately running extension cords for outdoor charging and aging wiring. Therefore, centralized battery swapping stations are gradually becoming the development trend for urban electric bicycle energy replenishment.

[0003] Currently, traditional battery swapping stations typically use a single isolated AC-DC module to charge the batteries in each battery compartment. This method is highly dependent on the grid's power supply capacity and the AC-DC module's power limit. During peak electricity consumption periods, grid voltage fluctuations or power limitations further reduce charging efficiency, extending battery charging times to several hours. This significantly contradicts the peak concentrated electricity demand of industries such as food delivery (typically concentrated within 2 hours). Furthermore, in cases of grid instability or extreme conditions, the AC-DC power supply may fail to function properly, resulting in no fully charged batteries available for replacement in the swapping station, severely impacting users' continuous power needs.

[0004] Therefore, how to provide a charging method and system for battery swapping cabinets based on DC bus, so as to improve battery charging efficiency, adaptability to grid fluctuations, and centralized and efficient battery management and energy dispatch, has become an urgent technical problem to be solved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a charging method and system for a battery swapping cabinet based on a DC bus, so as to improve battery charging efficiency, adaptability to grid fluctuations, and centralized and efficient management and energy dispatch of batteries.

[0006] In a first aspect, the present invention provides a charging method for a battery swapping cabinet based on a DC bus, comprising the following steps: Step S1: Set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. Step S2: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. Step S3: When the timestamp is during the peak battery swapping period, select the high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold, select the low-priority batteries that need to be discharged based on the SOC range, and connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. Step S4: The battery swapping cabinet delivers power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. Step S5: The battery swapping cabinet records the charging log in real time, dynamically updates the battery swapping idle period and battery swapping peak period based on the charging log, and encrypts and backs up the charging log.

[0007] Furthermore, in step S1, the upper limit threshold of SOC is greater than the upper limit of the SOC interval but less than 100%; the lower limit of the SOC interval is greater than 5%; the quantity threshold is a positive integer; and the first charging current is less than the second charging current.

[0008] Furthermore, step S2 specifically includes: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

[0009] Furthermore, step S3 specifically includes: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

[0010] Furthermore, step S4 specifically includes: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. Step S5 specifically involves: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup. Secondly, the present invention provides a battery swapping cabinet charging system based on a DC bus, comprising the following modules: The parameter setting module is used to set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. The idle period charging module is used to collect the current timestamp of the battery swapping cabinet. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. The battery grading module is used to select high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold when the timestamp is in the peak period of battery swapping, and to select low-priority batteries that need to be discharged based on the SOC range, and to connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. The peak-hour charging module is used by the battery swapping cabinet to deliver power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. The charging log management module is used to record charging logs in real time at the battery swapping cabinet, dynamically update the battery swapping idle period and battery swapping peak period based on the charging logs, and encrypt and back up the charging logs.

[0011] Furthermore, in the parameter setting module, the upper limit threshold of SOC is greater than the upper limit of the SOC range but less than 100%; the lower limit of the SOC range is greater than 5%; the quantity threshold is a positive integer; and the first charging current is less than the second charging current.

[0012] Furthermore, the idle period charging module is specifically used for: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

[0013] Furthermore, the battery grading module is specifically used for: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

[0014] Furthermore, the peak-hour charging module is specifically used for: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. The charging log management module is specifically used for: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup. The advantages of this invention are: 1. The battery swapping cabinet is configured with features including an idle period, peak period, SOC upper limit threshold, SOC range, quantity threshold, first charging current, and second charging current. The cabinet collects the current timestamp. When the timestamp is during an idle period, the isolated AC-CDC power module supplies power from the grid to the non-isolated bidirectional DC-CDC power module via the DC bus. The non-isolated bidirectional DC-CDC power module charges the corresponding battery using the first charging current. When the timestamp is during a peak period, high-priority batteries requiring charging are selected based on the SOC upper limit threshold and the quantity threshold, while low-priority batteries requiring discharging are selected based on the SOC range. The non-isolated bidirectional DC-CDC power modules connected to each high-priority and low-priority battery are connected in parallel. The battery swapping cabinet supplies power to the non-isolated bidirectional DC-CDC power module via the isolated AC-CDC power module and the low-priority battery. The non-isolated bidirectional DC-CDC power module charges the corresponding high-priority battery using the second charging current. Priority battery charging; the battery swapping cabinet records charging logs in real time, dynamically updating the battery swapping idle period and peak period based on the charging logs, and encrypting and backing up the charging logs; that is, through a DC bus architecture combined with a dynamic battery hierarchical scheduling mechanism, high SOC batteries (high-priority batteries that need charging) are used to achieve fast charging with a second charging current during peak battery swapping periods, while medium-capacity batteries (low-priority batteries) within the SOC range are directly discharged and supplied through the DC bus, significantly improving charging efficiency; through the energy mutual supply mode between batteries, the cabinet automatically switches to battery power supply when the grid fluctuates or fails, reducing dependence on the grid; and intelligently selects charging and discharging batteries based on the upper limit threshold and SOC range, combined with log-driven dynamic adjustment of time periods, to achieve centralized optimization scheduling and flexible energy allocation of battery resources, thereby greatly improving battery charging efficiency, adaptability to grid fluctuations, and achieving centralized and efficient management and energy scheduling of batteries.

[0015] 2. By setting idle and peak periods for battery swapping and automatically switching charging modes based on timestamps, the system prioritizes using grid power during idle periods and utilizes internal battery energy transfer during peak periods. This reduces peak grid load, lowers energy costs, and improves overall system efficiency.

[0016] 3. By using the SOC upper limit threshold and quantity threshold, the system intelligently selects high-priority batteries for fast charging and low-priority batteries for discharging, ensuring that the batteries that users urgently need can be fully charged first, improving the response speed of the battery swapping service and the user experience, and reducing waiting time.

[0017] 4. The use of a DC bus for power transmission avoids losses from multiple AC-DC conversions, allowing direct charging and discharging with DC power. The use of a non-isolated bidirectional DC-DC power module further optimizes voltage conversion efficiency, reduces energy loss, and improves charging efficiency.

[0018] 5. By recording charging logs in real time and dynamically updating battery swapping idle and peak periods, the system can learn usage patterns and optimize charging strategies itself, enabling the system to adapt to changes in demand at different times and improve long-term operating efficiency and reliability.

[0019] 6. Charging logs use the hash256 algorithm to calculate hash values ​​and the SM4 algorithm for encryption, ensuring data integrity and confidentiality, preventing tampering and unauthorized access, and distributed backup further improves data reliability.

[0020] 7. During peak periods, the internal battery energy transfer reduces dependence on the power grid and lowers electricity costs (especially avoiding peak electricity prices); at the same time, through SOC range and current control (the first charging current is less than the second charging current), overcharging or over-discharging of the battery is avoided, extending battery life and reducing maintenance and replacement costs.

[0021] 8. The system adopts isolated ACDC power modules and non-isolated bidirectional DCDC power modules. The modular design of the system makes it easy to integrate new battery types or expand cabinet capacity, reducing the complexity of upgrades and maintenance and improving the scalability of the system.

[0022] 9. Real-time acquisition of battery SOC and recording of charging and discharging parameters enable rapid response to changes in battery status, ensuring a stable and reliable charging process; precise current control optimizes charging speed and safety.

[0023] 10. Through intelligent time management (such as distinguishing between idle and peak periods for battery swapping) and SOC-based priority control, energy use is optimized, peak grid load is reduced, and charging response speed and user experience are improved. The adoption of a DC bus architecture and non-isolated bidirectional DC-DC power modules improves energy conversion efficiency and reduces energy loss. Dynamic adaptive adjustment of charging strategies enhances system flexibility and reliability through real-time log recording and learning. At the same time, data encryption and backup ensure security. Cost savings and extended battery life are achieved through internal energy transfer and precise current control. Modular design supports scalability, real-time monitoring ensures stability, and promotes environmental compliance and audit friendliness. Overall, it achieves an efficient, safe, and economical battery swapping service. Attached Figure Description

[0024] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0025] Figure 1 This is a flowchart of a charging method for a battery swapping cabinet based on a DC bus according to the present invention.

[0026] Figure 2 This is a schematic diagram of the structure of a battery swapping cabinet charging system based on a DC bus according to the present invention.

[0027] Figure 3 This is a schematic diagram of the hardware architecture of the present invention. Detailed Implementation

[0028] The overall concept of the technical solution in this application embodiment is as follows: By combining a DC bus architecture with a dynamic battery hierarchical scheduling mechanism, high-SOC batteries are used to achieve rapid charging with a second charging current during peak battery swapping periods. At the same time, medium-capacity batteries within the SOC range are directly discharged and supplied through the DC bus, significantly improving charging efficiency. Through the inter-battery energy mutual supply mode, the system automatically switches to in-cabinet battery power supply when the grid fluctuates or fails, reducing dependence on the grid. Based on the SOC upper limit threshold and SOC range, charging and discharging batteries are intelligently selected, and combined with log-driven time-period dynamic adjustment, centralized optimization scheduling and elastic energy allocation of battery resources are achieved to improve battery charging efficiency, adaptability to grid fluctuations, and centralized and efficient management and energy scheduling of batteries. Please refer to Figures 1 to 3 As shown, a preferred embodiment of the present invention, a charging method for a battery swapping cabinet based on a DC bus, includes the following steps: Step S1: Set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. Step S2: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. Step S3: When the timestamp is during the peak battery swapping period, select the high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold, select the low-priority batteries that need to be discharged based on the SOC range, and connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. Step S4: The battery swapping cabinet delivers power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. Step S5: The battery swapping cabinet records the charging log in real time, dynamically updates the battery swapping idle period and battery swapping peak period based on the charging log, and encrypts and backs up the charging log.

[0029] The battery swapping cabinet consists of an isolated AC-CDC power module, several non-isolated bidirectional DC-CDC power modules, several charging switches, and several parallel switches. The DC terminal of the isolated AC-CDC power module is connected to the input terminal of each non-isolated bidirectional DC-CDC power module via a DC bus, and the AC terminal is connected to the power grid. The non-isolated bidirectional DC-CDC power modules are connected in parallel via parallel switches (e.g., ...). Figure 3 (K1-K8 in the model); each non-isolated bidirectional DC-DC power module is connected to the battery via a charging switch (e.g., K1-K8). Figure 3 (S1-S10 in the middle).

[0030] The power of the isolated AC-CDC power module = the power of the non-isolated bidirectional DC-CDC power module * N * 120%; N is the number of non-isolated bidirectional DC-CDC power modules.

[0031] In step S1, the upper limit threshold of SOC is greater than the upper limit of the SOC interval but less than 100%; the lower limit of the SOC interval is greater than 5%; the quantity threshold is a positive integer; and the first charging current is less than the second charging current.

[0032] Step S2 specifically involves: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

[0033] Step S3 specifically involves: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

[0034] Step S4 specifically involves: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. Step S5 specifically involves: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup.

[0035] Basic event records include: Timestamp: accurately records the time of occurrence of each charge / discharge operation (year-month-day hour:minute:second); Battery ID: accurately records the identification code of the battery participating in the operation; Operation Type: clearly records whether it is "charging", "discharging" (powering other batteries) or "idle / standby", distinguishing between grid charging, inter-battery scheduled discharge, or no participation; Start / End Time: records the specific start and end times of the charging or discharging cycle.

[0036] Key battery status parameters include: Start SOC: the real-time SOC value of the battery at the start of the operation (charging / discharging); End SOC: the real-time SOC value of the battery at the end of the operation (charging / discharging); Target SOC (if applicable): for example, whether the charging target is the upper limit threshold of SOC or fully charged (100%); Battery Temperature: temperature records at key nodes during the operation (such as start, peak, and end), associated with safety monitoring.

[0037] The parameters for the charging and discharging process include: Charge / Discharge Current: the actual applied current value (such as the first charging current, the second charging current, or the discharging current), accurate to amperes (A); Voltage: the trend or key point record of the battery terminal voltage during operation; Energy Transfer: the energy (kWh) obtained from the grid / other batteries during this charge, or the energy (kWh) contributed to the DC bus during discharge.

[0038] System scheduling and decision information includes: Current period flag (Period Flag): marks the period in which the system is located when the operation occurs (battery swapping idle period / battery swapping peak period); Scheduling priority flag (Priority Flag): records the role of the battery in this operation (high priority battery / low priority battery / not participating in scheduling); Associated battery information (AssociatedBattery ID, during scheduling): when performing inter-battery energy scheduling, records the ID of the low priority battery providing power and the ID of the high priority battery receiving power; Scheduling trigger criteria (Trigger Criteria): briefly records the key conditions that trigger this scheduling decision (such as "SOC ranking result", "quantity threshold met", "SOC within the range").

[0039] System status and external inputs include: Grid Input Status: Records whether the grid is supplying power normally and the input power / voltage fluctuations during operation (if monitored); DC Bus Voltage: Records key points during operation, reflecting bus stability; Switch Status Change: Records the closing / opening operations and times of key switches such as charging switches and parallel switches; Non-isolated bidirectional DC-DC module status: Whether the module is working normally and whether there are fault codes.

[0040] Statistical and aggregated data includes: Number of battery requests / uses within a time period: statistics on the frequency of battery replacements by users during peak / idle periods; Average charging time within a time period: statistics on the average time taken to charge a battery from low SOC to the target SOC during different time periods; Proportion / number of batteries participating in scheduling within a time period: statistics on the number of low-priority batteries participating in discharge and the number of high-priority batteries receiving fast charging during peak periods; Grid dependence / battery contribution within a time period: calculation of the proportion of energy directly supplied by the grid during peak periods vs. the proportion of energy contributed by low-priority batteries; SOC distribution statistics: recording the SOC distribution of all batteries in the cabinet at specific time points (such as the beginning / end of peak periods). A preferred embodiment of the present invention, a battery swapping cabinet charging system based on a DC bus, includes the following modules: The parameter setting module is used to set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. The idle period charging module is used to collect the current timestamp of the battery swapping cabinet. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. The battery grading module is used to select high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold when the timestamp is in the peak period of battery swapping, and to select low-priority batteries that need to be discharged based on the SOC range, and to connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. The peak-hour charging module is used by the battery swapping cabinet to deliver power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. The charging log management module is used to record charging logs in real time at the battery swapping cabinet, dynamically update the battery swapping idle period and battery swapping peak period based on the charging logs, and encrypt and back up the charging logs.

[0041] The battery swapping cabinet consists of an isolated AC-CDC power module, several non-isolated bidirectional DC-CDC power modules, several charging switches, and several parallel switches. The DC terminal of the isolated AC-CDC power module is connected to the input terminal of each non-isolated bidirectional DC-CDC power module via a DC bus, and the AC terminal is connected to the power grid. The non-isolated bidirectional DC-CDC power modules are connected in parallel via parallel switches (e.g., ...). Figure 3 (K1-K8 in the model); each non-isolated bidirectional DC-DC power module is connected to the battery via a charging switch (e.g., K1-K8). Figure 3 (S1-S10 in the middle).

[0042] The power of the isolated AC-CDC power module = the power of the non-isolated bidirectional DC-CDC power module * N * 120%; N is the number of non-isolated bidirectional DC-CDC power modules.

[0043] In the parameter setting module, the upper limit threshold of SOC is greater than the upper limit of the SOC range but less than 100%; the lower limit of the SOC range is greater than 5%; the quantity threshold is a positive integer; and the first charging current is less than the second charging current.

[0044] The idle period charging module is specifically used for: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

[0045] The battery grading module is specifically used for: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

[0046] The peak-hour charging module is specifically used for: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. The charging log management module is specifically used for: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup.

[0047] Basic event records include: Timestamp: accurately records the time of occurrence of each charge / discharge operation (year-month-day hour:minute:second); Battery ID: accurately records the identification code of the battery participating in the operation; Operation Type: clearly records whether it is "charging", "discharging" (powering other batteries) or "idle / standby", distinguishing between grid charging, inter-battery scheduled discharge, or no participation; Start / End Time: records the specific start and end times of the charging or discharging cycle.

[0048] Key battery status parameters include: Start SOC: the real-time SOC value of the battery at the start of the operation (charging / discharging); End SOC: the real-time SOC value of the battery at the end of the operation (charging / discharging); Target SOC (if applicable): for example, whether the charging target is the upper limit threshold of SOC or fully charged (100%); Battery Temperature: temperature records at key nodes during the operation (such as start, peak, and end), associated with safety monitoring.

[0049] The parameters for the charging and discharging process include: Charge / Discharge Current: the actual applied current value (such as the first charging current, the second charging current, or the discharging current), accurate to amperes (A); Voltage: the trend or key point record of the battery terminal voltage during operation; Energy Transfer: the energy (kWh) obtained from the grid / other batteries during this charge, or the energy (kWh) contributed to the DC bus during discharge.

[0050] System scheduling and decision information includes: Current period flag (Period Flag): marks the period in which the system is located when the operation occurs (battery swapping idle period / battery swapping peak period); Scheduling priority flag (Priority Flag): records the role of the battery in this operation (high priority battery / low priority battery / not participating in scheduling); Associated battery information (AssociatedBattery ID, during scheduling): when performing inter-battery energy scheduling, records the ID of the low priority battery providing power and the ID of the high priority battery receiving power; Scheduling trigger criteria (Trigger Criteria): briefly records the key conditions that trigger this scheduling decision (such as "SOC ranking result", "quantity threshold met", "SOC within the range").

[0051] System status and external inputs include: Grid Input Status: Records whether the grid is supplying power normally and the input power / voltage fluctuations during operation (if monitored); DC Bus Voltage: Records key points during operation, reflecting bus stability; Switch Status Change: Records the closing / opening operations and times of key switches such as charging switches and parallel switches; Non-isolated bidirectional DC-DC module status: Whether the module is working normally and whether there are fault codes.

[0052] Statistical and aggregated data includes: Number of battery requests / uses within a time period: statistics on the frequency of battery replacements by users during peak / idle periods; Average charging time within a time period: statistics on the average time taken to charge a battery from low SOC to the target SOC during different time periods; Proportion / number of batteries participating in scheduling within a time period: statistics on the number of low-priority batteries participating in discharge and the number of high-priority batteries receiving fast charging during peak periods; Grid dependence / battery contribution within a time period: calculation of the proportion of energy directly supplied by the grid during peak periods vs. the proportion of energy contributed by low-priority batteries; SOC distribution statistics: recording the SOC distribution of all batteries in the cabinet at specific time points (such as the beginning / end of peak periods). In summary, the advantages of this invention are: 1. The battery swapping cabinet is configured with features including an idle period, peak period, SOC upper limit threshold, SOC range, quantity threshold, first charging current, and second charging current. The cabinet collects the current timestamp. When the timestamp is during an idle period, the isolated AC-CDC power module supplies power from the grid to the non-isolated bidirectional DC-CDC power module via the DC bus. The non-isolated bidirectional DC-CDC power module charges the corresponding battery using the first charging current. When the timestamp is during a peak period, high-priority batteries requiring charging are selected based on the SOC upper limit threshold and the quantity threshold, while low-priority batteries requiring discharging are selected based on the SOC range. The non-isolated bidirectional DC-CDC power modules connected to each high-priority and low-priority battery are connected in parallel. The battery swapping cabinet supplies power to the non-isolated bidirectional DC-CDC power module via the isolated AC-CDC power module and the low-priority battery. The non-isolated bidirectional DC-CDC power module charges the corresponding high-priority battery using the second charging current. Priority battery charging; the battery swapping cabinet records charging logs in real time, dynamically updating the battery swapping idle period and peak period based on the charging logs, and encrypting and backing up the charging logs; that is, through a DC bus architecture combined with a dynamic battery hierarchical scheduling mechanism, high SOC batteries (high-priority batteries that need charging) are used to achieve fast charging with a second charging current during peak battery swapping periods, while medium-capacity batteries (low-priority batteries) within the SOC range are directly discharged and supplied through the DC bus, significantly improving charging efficiency; through the energy mutual supply mode between batteries, the cabinet automatically switches to battery power supply when the grid fluctuates or fails, reducing dependence on the grid; and intelligently selects charging and discharging batteries based on the upper limit threshold and SOC range, combined with log-driven dynamic adjustment of time periods, to achieve centralized optimization scheduling and flexible energy allocation of battery resources, thereby greatly improving battery charging efficiency, adaptability to grid fluctuations, and achieving centralized and efficient management and energy scheduling of batteries.

[0053] 2. By setting idle and peak periods for battery swapping and automatically switching charging modes based on timestamps, the system prioritizes using grid power during idle periods and utilizes internal battery energy transfer during peak periods. This reduces peak grid load, lowers energy costs, and improves overall system efficiency.

[0054] 3. By using the SOC upper limit threshold and quantity threshold, the system intelligently selects high-priority batteries for fast charging and low-priority batteries for discharging, ensuring that the batteries that users urgently need can be fully charged first, improving the response speed of the battery swapping service and the user experience, and reducing waiting time.

[0055] 4. The use of a DC bus for power transmission avoids losses from multiple AC-DC conversions, allowing direct charging and discharging with DC power. The use of a non-isolated bidirectional DC-DC power module further optimizes voltage conversion efficiency, reduces energy loss, and improves charging efficiency.

[0056] 5. By recording charging logs in real time and dynamically updating battery swapping idle and peak periods, the system can learn usage patterns and optimize charging strategies itself, enabling the system to adapt to changes in demand at different times and improve long-term operating efficiency and reliability.

[0057] 6. Charging logs use the hash256 algorithm to calculate hash values ​​and the SM4 algorithm for encryption, ensuring data integrity and confidentiality, preventing tampering and unauthorized access, and distributed backup further improves data reliability.

[0058] 7. During peak periods, the internal battery energy transfer reduces dependence on the power grid and lowers electricity costs (especially avoiding peak electricity prices); at the same time, through SOC range and current control (the first charging current is less than the second charging current), overcharging or over-discharging of the battery is avoided, extending battery life and reducing maintenance and replacement costs.

[0059] 8. The system adopts isolated ACDC power modules and non-isolated bidirectional DCDC power modules. The modular design of the system makes it easy to integrate new battery types or expand cabinet capacity, reducing the complexity of upgrades and maintenance and improving the scalability of the system.

[0060] 9. Real-time acquisition of battery SOC and recording of charging and discharging parameters enable rapid response to changes in battery status, ensuring a stable and reliable charging process; precise current control optimizes charging speed and safety.

[0061] 10. Through intelligent time management (such as distinguishing between idle and peak periods for battery swapping) and SOC-based priority control, energy use is optimized, peak grid load is reduced, and charging response speed and user experience are improved. The adoption of a DC bus architecture and non-isolated bidirectional DC-DC power modules improves energy conversion efficiency and reduces energy loss. Dynamic adaptive adjustment of charging strategies enhances system flexibility and reliability through real-time log recording and learning. At the same time, data encryption and backup ensure security. Cost savings and extended battery life are achieved through internal energy transfer and precise current control. Modular design supports scalability, real-time monitoring ensures stability, and promotes environmental compliance and audit friendliness. Overall, it achieves an efficient, safe, and economical battery swapping service.

[0062] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the present invention. Equivalent modifications and variations made by those skilled in the art in accordance with the spirit of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A charging method for a battery swapping cabinet based on a DC bus, characterized in that: Includes the following steps: Step S1: Set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. Step S2: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. Step S3: When the timestamp is during the peak battery swapping period, select the high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold, select the low-priority batteries that need to be discharged based on the SOC range, and connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. Step S4: The battery swapping cabinet delivers power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. Step S5: The battery swapping cabinet records the charging log in real time, dynamically updates the battery swapping idle period and battery swapping peak period based on the charging log, and encrypts and backs up the charging log.

2. The charging method for a battery swapping cabinet based on a DC bus as described in claim 1, characterized in that: In step S1, the upper limit of SOC is greater than the upper limit of the SOC interval but less than 100%; the lower limit of the SOC interval is greater than 5%. The quantity threshold is a positive integer; the first charging current is less than the second charging current.

3. The charging method for a battery swapping cabinet based on a DC bus as described in claim 1, characterized in that: Step S2 specifically involves: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

4. The charging method for a battery swapping cabinet based on a DC bus as described in claim 1, characterized in that: Step S3 specifically involves: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

5. The charging method for a battery swapping cabinet based on a DC bus as described in claim 1, characterized in that: Step S4 specifically involves: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. Step S5 specifically involves: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup.

6. A battery swapping cabinet charging system based on a DC bus, characterized in that: Includes the following modules: The parameter setting module is used to set a battery swapping idle period, a battery swapping peak period, a SOC upper limit threshold, a SOC range, a quantity threshold, a first charging current, and a second charging current for the battery swapping cabinet. The idle period charging module is used to collect the current timestamp of the battery swapping cabinet. When the timestamp is in the battery swapping idle period, the isolated ACDC power module transmits the power from the grid to the non-isolated bidirectional DCDC power module through the DC bus. The non-isolated bidirectional DCDC power module charges the corresponding battery based on the first charging current. The battery grading module is used to select high-priority batteries that need to be charged based on the upper limit threshold of SOC and the quantity threshold when the timestamp is in the peak period of battery swapping, and to select low-priority batteries that need to be discharged based on the SOC range, and to connect the non-isolated bidirectional DC-DC power modules connected to each high-priority battery and low-priority battery in parallel. The peak-hour charging module is used by the battery swapping cabinet to deliver power to the non-isolated bidirectional DC-DC power module through the isolated ACDC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. The charging log management module is used to record charging logs in real time at the battery swapping cabinet, dynamically update the battery swapping idle period and battery swapping peak period based on the charging logs, and encrypt and back up the charging logs.

7. The battery swapping cabinet charging system based on a DC bus as described in claim 6, characterized in that: In the parameter setting module, the upper limit of SOC is greater than the upper limit of the SOC interval but less than 100%; the lower limit of the SOC interval is greater than 5%. The quantity threshold is a positive integer; the first charging current is less than the second charging current.

8. The battery swapping cabinet charging system based on a DC bus as described in claim 6, characterized in that: The idle period charging module is specifically used for: The battery swapping cabinet collects the current timestamp. When the timestamp is in the battery swapping idle period, the battery swapping cabinet closes the charging switch connected to the battery. The isolated AC-DC power module converts the power input from the grid from AC to DC, and then transmits the power to the non-isolated bidirectional DC-DC power module through the DC bus. The non-isolated bidirectional DC-DC power module performs voltage conversion on the input power and charges the corresponding battery based on the first charging current.

9. A battery swapping cabinet charging system based on a DC bus as described in claim 6, characterized in that: The battery grading module is specifically used for: The battery swapping cabinet collects the real-time SOC of each battery. When the timestamp is during the peak battery swapping period, the batteries whose real-time SOC has not reached the upper limit threshold are sorted to obtain a SOC sorting list. Based on the quantity threshold, the battery with the highest SOC is selected from the SOC sorting list as the high-priority battery that needs to be charged. Based on the SOC range, the low-priority battery that needs to be discharged is selected, and the corresponding parallel switch is closed to connect the non-isolated bidirectional DC-DC power modules connected to the high-priority and low-priority batteries in parallel.

10. The battery swapping cabinet charging system based on a DC bus as described in claim 6, characterized in that: The peak-hour charging module is specifically used for: The battery swapping cabinet transmits power to the non-isolated bidirectional DC-DC power module via the DC bus by isolating the AC-DC power module and the low-priority battery. The non-isolated bidirectional DC-DC power module charges the corresponding high-priority battery based on the second charging current. When the real-time SOC of one of the high-priority batteries reaches the upper limit threshold of SOC, a new high-priority battery is selected from the latest SOC sorting list for charging. The charging log management module is specifically used for: The battery swapping cabinet records in real time at least the following charging logs: basic event records, key battery status parameters, charging and discharging process parameters, system scheduling and decision information, system status and external inputs, and statistical and aggregated data. Based on the charging logs, the cabinet dynamically updates the battery swapping idle period and peak battery swapping period. The hash value of the charging logs is calculated using the hash256 algorithm, and the charging logs and hash values ​​are encrypted into encrypted logs using the SM4 algorithm. The encrypted logs are then stored and distributed for backup.

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