Dual-gun charging compatibility strategy and new energy logistics vehicle

Abstract

The application discloses a double-gun charging compatibility strategy and a new energy logistics vehicle, relates to the field of new energy automobile power battery charging control technology, and comprises a double-gun access module, a charging compatibility control module and a voltage request adjusting module.The double-gun access module is used for charging the new energy logistics vehicle in a double-gun charging state by adopting two charging guns to simultaneously connect charging piles for charging, two charging piles simultaneously output charging power, the output currents of the two charging guns are superposed, the actual battery charging current is obtained, and the actual battery charging current is taken as a data basis for subsequent charging control.Through the double-gun charging overcurrent threshold optimization and the charging voltage dynamic adjusting strategy, the application improves the compatibility of the new energy light truck to charging piles of different brands and different regions, solves the problems of double-gun output deviation superposition and different voltage platform adaptation, guarantees the safety of the battery, and realizes fast energy supplement and efficient utilization of charging resources.

Description

Technical Field

[0001] This invention relates to the field of charging control technology for power batteries in new energy vehicles, specifically to a dual-gun charging compatibility strategy and a new energy logistics vehicle. Background Technology

[0002] With the rapid development of the new energy vehicle industry, the high-voltage charging safety of new energy logistics vehicles has become a core issue of concern for vehicle manufacturers. In addition to meeting relevant regulatory requirements, it is of great significance to further ensure the safety and charging convenience of vehicle users through redundant design. Meanwhile, vehicle charging safety has become a crucial aspect of the use of new energy vehicles, and charging compatibility—that is, the ability of a vehicle to be compatible with charging stations of different types and in different regions—has become a significant factor affecting customer charging convenience. For the high-voltage architecture of light trucks in new energy commercial vehicles, due to the integrated development of the battery pack, the positive and negative relays of the main circuit are usually located inside the battery pack. As the battery charging rate continues to increase, the traditional single-gun charging method is no longer sufficient to meet the current demand for high-power fast charging. Furthermore, the output power of commonly used charging stations on the market is limited and cannot be effectively matched with fast charging technology.

[0003] The existing technology has the following shortcomings: In the current technology, mainstream solutions typically use a single charging gun for charging, with the fast-charging relay located inside the multi-functional controller or battery pack. When charging starts, the BMS (Battery Management System) enables the charging relay to close via CAN messages or BMU (Battery Management Unit) hard-wired connection, connecting the vehicle's high-voltage system to the charging pile. Data exchange with the charging pile is conducted according to the GB / T 27930-2023 communication protocol, sending parameters such as the maximum allowable charging voltage and allowable charging current. When the charging pile's output current exceeds 1.05 times the BMS's allowable charging current for a certain period, the BMS stops charging and reports an overcurrent fault. Simultaneously, when the maximum output voltage reported by the charging pile is lower than the voltage required for a full battery charge, charging is usually stopped directly, and a matching fault is reported. While single-gun charging itself does not have obvious drawbacks, with the continuous increase in battery charging rates, commonly used 120kW charging piles can no longer meet the continuous high-power charging needs of large-capacity battery packs, while using supercharging piles increases charging service costs. Furthermore, when the maximum output voltage of the charging pile cannot meet the battery's full-charge voltage requirements, the vehicle cannot continue charging, resulting in poor compatibility between charging piles with different output capabilities, affecting vehicle charging efficiency and user charging convenience. The information disclosed in the background section is only for enhancing the understanding of the background of this disclosure and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this invention is to provide a dual-gun charging compatibility strategy and a new energy logistics vehicle to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a dual-gun charging compatibility strategy and a new energy logistics vehicle, comprising a dual-gun access module, a charging compatibility control module, and a voltage request adjustment module: With the dual-gun access module, the new energy logistics vehicle enters the dual-gun charging state, using two charging guns to connect to the charging piles simultaneously for charging. The two charging piles output charging power simultaneously, and the output currents of the two charging guns are superimposed to obtain the actual charging current of the battery. The actual charging current of the battery is then used as the data basis for subsequent charging control. The charging compatibility control module performs charging current compatibility control based on the actual charging current of the battery. When the actual charging current of the battery exceeds 10% of the requested charging current, the requested charging current is reduced; when the actual charging current of the battery exceeds 20% of the requested charging current, charging is stopped to protect battery safety. Dual-gun charging is maintained as long as the actual charging current of the battery does not exceed 20% of the requested charging current. After completing the charging current compatibility control, the voltage request adjustment module obtains the maximum output voltage sent by the charging pile. When the maximum output voltage is lower than the maximum charging voltage of the battery, the battery management system requests the charging pile to output voltage according to the maximum output voltage and stops charging when the actual charging voltage reaches the maximum output voltage. When the maximum output voltage reaches or exceeds the maximum charging voltage of the battery, the battery management system requests the charging pile to output voltage according to the maximum charging voltage of the battery and stops charging when the battery is fully charged.

[0006] Dual-gun charging means that the new energy light truck is connected to two charging piles at the same time. The charging current output from the two charging piles is obtained through the two charging guns respectively, and the charging current output from the two charging guns is superimposed to form the actual charging current of the vehicle. The two charging piles output power independently, and the vehicle completes high-power energy replenishment based on the superimposed charging power output from the two guns. This improves the overall charging power of the new energy light truck and meets the needs of rapid energy replenishment without the need to configure supercharging piles.

[0007] In dual-gun charging mode, the output current of the two charging piles is acquired separately, and the actual charging current of the battery is determined based on the output current adjustment characteristics of the two charging piles. When there is an adjustment deviation in the output current of a single charging pile, the output currents of the two charging piles are superimposed for judgment, so that the charging control can adapt to the output current deviation caused by the difference in the adjustment accuracy of the power modules of charging piles of different brands and regions, thereby improving the compatibility between the vehicle and the charging pile during dual-gun charging.

[0008] During the charging current compatibility control process, a first current control threshold and a second current protection threshold are set. When the actual charging current of the battery exceeds the first current control threshold of the requested charging current, the requested charging current is reduced to reduce the actual output current of the charging pile. When the actual charging current of the battery exceeds the second current protection threshold, charging is stopped and charging overcurrent fault information is output to ensure the charging safety of the power battery while improving the compatibility of dual-gun charging.

[0009] The first current control threshold corresponds to 10% of the requested charging current. When the actual charging current of the battery exceeds 10% of the requested charging current, the requested charging current value is actively reduced to avoid accidental charging stop caused by the superposition of the output adjustment deviations of the two charging piles. The second current protection threshold corresponds to 20% of the requested charging current. When the output current value of the dual guns exceeds 20% of the requested charging current, charging is stopped to protect the power battery and the vehicle's high-voltage charging circuit.

[0010] During the charging voltage adaptation control process, the maximum output voltage information sent by the charging pile is obtained, and the maximum output voltage of the charging pile is compared with the maximum charging voltage of the power battery. When the maximum output voltage of the charging pile is lower than the maximum charging voltage of the power battery, the requested voltage sent to the charging pile is adjusted according to the maximum output voltage of the charging pile to enable the vehicle to continue charging. When the maximum output voltage of the charging pile meets the maximum charging voltage requirement of the power battery, the requested voltage is sent according to the maximum charging voltage of the power battery.

[0011] When the maximum output voltage sent by the charging pile is detected to be 750V, and the maximum voltage of the power battery exceeds 750V, the vehicle does not stop the charging process, but sends a request voltage to the charging pile according to 750V, so that the charging pile can charge according to the 750V output voltage; when the actual voltage of the power battery reaches 750V, the charging process ends, so as to improve the vehicle's adaptability to charging piles with voltages lower than the full charge voltage of the power battery.

[0012] When it is detected that the maximum output voltage of the charging pile exceeds the full charge voltage of the power battery, the highest voltage request value is sent to the charging pile according to the full charge voltage of the power battery, so that the charging pile outputs voltage according to the charging needs of the power battery; when the power battery voltage gradually rises to the full charge voltage, the charging process ends, the power battery is fully charged, and the utilization efficiency of high voltage level charging piles is improved.

[0013] The new energy light truck includes a power battery, a battery management system, and a dual-gun charging interface. The battery management system is used to obtain dual-gun charging status information, collect charging pile output current and charging pile output voltage information, and adjust the requested charging current and requested charging voltage according to the obtained information to achieve current compatibility control during dual-gun charging and charging adaptation control between charging piles with different output voltages.

[0014] The charging control method achieves compatible charging for new energy light trucks in different brands, regions, and charging pile environments with different output capabilities by superimposing the output power of the dual guns, current deviation compensation control, and active output voltage adaptation control. In particular, by adjusting the dual-gun charging overcurrent protection strategy, it avoids abnormal charging stoppage caused by the superposition of charging pile output deviations, and by adjusting the requested voltage, it avoids charging failure due to insufficient charging pile voltage, thereby improving the charging stability and energy replenishment efficiency of new energy light trucks.

[0015] The technical effects and advantages provided by the present invention in the above technical solution are as follows: This invention, by setting an overcurrent threshold control strategy for dual-gun charging of new energy light trucks, can effectively meet the adaptation needs of output deviation superposition during dual-gun charging of different brands and regions. In dual-gun charging mode, the two charging piles output current separately. Due to differences in the adjustment accuracy of the power modules of different charging piles, the output deviation of a single charging pile may occur within a certain range. When both guns work simultaneously, the output deviations of the two charging piles will superimpose, causing the actual charging current to exceed the requested current. By adjusting the overcurrent threshold under dual-gun charging conditions, the charging system can adapt to the superposition of output current changes between the two guns. This reduces the false charging stoppage caused by normal output deviations of the charging piles while ensuring battery safety, improves the compatibility of new energy light trucks with charging piles of different brands and regions, and enables stable and efficient dual-gun rapid energy replenishment using existing charging facilities.

[0016] This invention improves the charging compatibility of new energy light trucks with charging piles of different output voltage levels by actively adjusting the requested voltage value sent to the charging pile based on its output voltage. During charging, the maximum output voltage provided by the charging pile is identified and adjusted according to the actual full-charge voltage requirement of the power battery. When the charging pile's output voltage cannot meet the battery's full-charge requirement, charging is not stopped directly; instead, a request is made for the maximum output voltage that the charging pile can provide, allowing the vehicle to continue the current charging process. When the charging pile's output voltage can meet the battery's full-charge requirement, a request is made for the full-charge voltage of the battery, achieving a full charge. Through this dynamic voltage adaptation method, the charging success rate of new energy light trucks is improved in charging environments with different voltage platforms, expanding the vehicle's charging applicability and enhancing charging convenience and infrastructure utilization efficiency. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in this invention. For those skilled in the art, other drawings can be obtained based on these drawings.

[0018] Figure 1This is a schematic diagram of the modules of the present invention. Detailed Implementation

[0019] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided so that the description of this disclosure will be more complete and fully convey the concept of the exemplary embodiments to those skilled in the art.

[0020] This invention provides, for example Figure 1 The dual-gun charging compatibility strategy and its application to new energy logistics vehicles are illustrated below, with the specific steps as follows: When new energy logistics vehicles use a dual-gun charging method, two charging guns are connected to charging piles simultaneously, allowing the output power of the two charging piles to be superimposed. This enables the use of existing charging infrastructure to meet the high-power, fast-charging needs of vehicles without the need for large-scale supercharging pile construction, thereby improving vehicle charging efficiency and convenience. However, because the two charging piles output current independently during dual-gun charging, and different brands and regions use different power module control strategies and adjustment precision, the actual output current will inevitably deviate to some extent. Therefore, a different charging compatibility control strategy needs to be established for dual-gun charging compared to single-gun charging to ensure a stable and reliable charging process while also considering battery safety and charging efficiency.

[0021] During charging, the charging management system first identifies the dual-gun charging status and continuously acquires the output current of both charging guns. The output currents of the two charging guns are then summed to calculate the actual charging current of the battery. Simultaneously, the requested charging current is continuously acquired and compared in real time with the actual charging current to determine if the current charging status is within the normal range. When both charging guns output current according to the requested value, the actual charging current of the battery meets normal charging requirements. However, when the two charging stations have different adjustment precisions, resulting in output deviations, the actual charging current of the battery may be higher than the requested charging current. Therefore, it is necessary to adjust the overcurrent protection strategy for dual-gun charging to improve compatibility between charging stations of different brands and in different regions.

[0022] In traditional single-gun charging, the output current adjustment accuracy of the charging pile is typically controlled within 5% of the requested charging current. Therefore, when the output current exceeds 1.05 times the requested charging current, charging stops and an overcurrent fault is reported. This control strategy is suitable for single-gun charging, effectively balancing safety and protection requirements when a single charging gun is outputting. However, in dual-gun charging, each charging gun may have a certain range of output adjustment deviation. When the output deviations of the two charging guns are superimposed, the actual charging current of the battery may exceed the overcurrent protection threshold set for single-gun charging. If the protection strategy of single-gun charging is still adopted, i.e., charging stops immediately when the current exceeds 1.05 times the requested charging current, the overcurrent protection is easily triggered erroneously during dual-gun charging due to the superposition of the output deviations of the two charging guns. Even if the charging system is still within the safe operating range, this will cause the charging process to terminate prematurely, thereby reducing the compatibility of dual-gun charging and affecting the normal charging of the vehicle.

[0023] To address the aforementioned issues during dual-gun charging, the overcurrent threshold has been optimized. The original control method, which stopped charging when the current exceeded 1.05 times the requested charging current during single-gun charging, has been changed to a tiered control method. When the actual battery charging current reaches 1.1 times the requested charging current, charging is not immediately stopped. Instead, the requested current value is proactively reduced by 50%. By reducing the requested charging current, the charging pile is guided to gradually reduce its output current, allowing the actual battery charging current to return to a reasonable range. This avoids abnormal termination of the charging process due to short-term output deviations of the charging pile, while ensuring continuous charging.

[0024] After proactively reducing the requested current value by 50%, the actual charging current of the battery is continuously monitored. When the output current of both charging piles returns to the normal range, the requested charging current can be rematched to the current charging state, and the entire charging process continues normally. If the output current of the two charging guns continues to increase after reducing the requested charging current, causing the actual charging current of the battery to rise further, the charging state is continuously assessed. When the actual charging current of the battery reaches 1.2 times the requested charging current, it is considered that the current charging process has exceeded the allowable range. At this time, charging is immediately stopped, and an overcurrent fault is reported. By stopping charging, battery safety is protected, and continuous overcurrent is prevented from affecting the power battery, high-voltage system, and charging equipment.

[0025] With the above-mentioned hierarchical control method, the charging overcurrent control no longer uses a single threshold judgment, but instead sets different stage processing strategies based on the actual output characteristics of dual-gun charging. When the current slightly exceeds the requested range, the adjustment is completed by reducing the requested charging current; when the current continues to rise and exceeds the safe allowable range, charging is stopped and an overcurrent fault is reported. This method not only fully retains the charging safety protection function, but also fully considers the actual working conditions caused by the superposition of output deviations of the two charging piles during dual-gun charging, improves the charging compatibility of dual-gun charging of different brands and regions, avoids frequent false alarms caused by charging pile adjustment errors, and improves the success rate and stability of dual-gun charging.

[0026] In addition to charging current compatibility control, optimizations have also been made to address charging voltage compatibility. After communication is completed during charging, the system continuously acquires the maximum output voltage information sent by the charging pile and compares it with the battery's current full-charge voltage. Different charging piles can provide different maximum output voltages; for example, some charging piles have a maximum output voltage of 750V, while others can output 1000V. These different output capabilities directly affect the final charging state the vehicle can achieve.

[0027] In traditional control methods, when it is detected that the maximum output voltage of the charging pile cannot meet the battery's full-charge voltage requirements, charging is usually stopped directly or a matching fault is reported. The vehicle cannot continue to complete the charging process, causing normally functioning charging piles to be unable to continue providing energy replenishment services due to voltage platform differences. This reduces the vehicle's adaptability to charging piles of different specifications and also reduces the convenience of charging for users.

[0028] To address the above situations, when it is detected that the charging pile's output voltage does not meet the battery's full-charge voltage requirement, the system proactively adjusts the requested voltage value sent to the charging pile to meet the current charging needs, but not to achieve full charging. When the charging pile's maximum output voltage is lower than the battery's full-charge voltage, charging does not stop. Instead, the requested voltage sent to the charging pile is adjusted to the maximum voltage that the charging pile can currently output. The charging pile continues to output according to the adjusted requested voltage, and the vehicle continues to complete the current charging process. When the battery voltage gradually rises and reaches the charging pile's maximum output voltage, charging stops. At this point, although the vehicle cannot reach a full charge, it can fully utilize the current charging pile to achieve maximum energy replenishment, improving the vehicle's charging adaptability under different charging facility conditions.

[0029] For example, if the maximum output voltage of the charging pile is 750V, and the full charge voltage of the battery is higher than 750V, the voltage is requested to be adjusted to 750V. The charging pile continues to charge according to the 750V output voltage. As the state of charge of the battery increases, the battery terminal voltage gradually increases. When the actual charging voltage of the battery reaches 750V, the charging ends. The charging process will not be prematurely terminated due to insufficient output capacity of the charging pile, thus making full use of the output capacity of the charging pile to complete the current charging.

[0030] Furthermore, when the highest output voltage of the charging pile is detected to exceed the full-charge voltage of the battery, the highest voltage request value is reported according to the full-charge voltage request to achieve a full charge of the battery. In other words, when the charging pile has the output capability to meet the battery's full-charge requirements, the method of reducing the requested voltage is no longer used. Instead, the requested voltage is sent directly to the charging pile according to the battery's full-charge voltage. The charging pile continues to output according to the full-charge voltage until the power battery reaches a full charge state and then the charging ends, thereby achieving a full charge of the battery and fully utilizing the charging capability of the high-voltage platform charging pile.

[0031] Throughout the charging process, charging current compatibility control and charging voltage compatibility control work together. The former addresses the issue of output current deviations between different charging piles during dual-gun charging by adjusting the charging overcurrent threshold. It stops charging at 1.05 times the single-gun current, adjusting it to 1.1 times, proactively reducing the requested current value by 50%; and stops charging at 1.2 times the single-gun current, reporting a charging overcurrent fault. This improves charging compatibility across different brands and regions. The latter addresses the issue of differences in output voltage platforms among different charging piles. When the pile's output voltage does not meet the battery's full-charge voltage requirement, it proactively adjusts the requested voltage value sent to the pile to meet the current charging needs, but not to achieve full charge. When it detects that the pile's highest output voltage exceeds the battery's full-charge voltage, it reports the highest voltage request value according to the full-charge voltage request, achieving a full charge. Through these two compatibility strategies, while fully utilizing existing charging infrastructure, the adaptability, charging stability, and compatibility between different specifications of charging piles for new energy logistics vehicles with dual-gun charging are improved, and the overall charging efficiency of the vehicle is enhanced while ensuring battery safety.

[0032] Dual-gun charging module: Equipped with dual-gun charging, it enables the combined power of two charging piles even with limited supercharging station coverage, meeting the demands of ultra-fast charging. As the capacity of power batteries in new energy logistics vehicles continues to increase and charging rates rise, higher demands are placed on their rapid charging capabilities. However, the number of supercharging stations currently in the market is relatively limited. Large-scale supercharging station construction not only requires high construction costs but is also constrained by factors such as site availability, grid capacity, and supporting infrastructure, making widespread coverage difficult to achieve in the short term. Furthermore, the output power of many conventional DC charging piles already in use is relatively fixed. The charging power provided by a single charging pile is insufficient to meet the high-rate charging needs of new energy logistics vehicles, resulting in longer charging times and impacting operational efficiency.

[0033] To address the above situation, a dual-gun charging method is adopted for vehicle charging. This method achieves the combined power output of two charging stations without requiring extensive construction of supercharging piles, thus meeting the demands of ultra-fast charging. The dual-gun charging method utilizes existing charging infrastructure. Two charging guns are simultaneously connected to the vehicle's charging port, and both charging stations simultaneously output charging power to the vehicle. The charging power provided by both charging stations contributes to the vehicle's recharge, forming a dual-gun superimposed charging power mode. Compared to single-gun charging, dual-gun charging does not rely on higher-power supercharging equipment. Instead, it fully utilizes existing charging station resources, achieving a higher overall charging power through the superposition of the output power of the two guns, enabling rapid vehicle recharge. This improves the utilization rate of existing charging facilities and reduces the need for constructing high-power charging infrastructure.

[0034] During dual-gun charging, two charging guns establish charging connections with different charging piles. Each charging gun undertakes a portion of the charging power output. The vehicle's high-voltage system simultaneously receives electrical energy input from both charging guns and combines the output power of the two charging piles, achieving dual-gun superposition of charging power. Because both charging guns participate in charging simultaneously, the vehicle's overall charging capacity is no longer limited by the output power of a single charging pile. Instead, it utilizes the combined charging capacity of both charging piles, thus meeting the high-power charging needs of new energy logistics vehicles. For existing charging stations with a large number of charging piles around 120kW, there is no need to add higher-power charging equipment; the dual-gun charging method can increase the overall charging power of vehicles, providing a more efficient energy replenishment method for new energy logistics vehicles.

[0035] With dual-gun charging, vehicles can flexibly select the dual-gun charging mode according to the current charging environment. When a charging station is equipped with dual-gun charging facilities, the two charging guns are connected to the corresponding charging piles, and both charging piles output electrical energy simultaneously. The vehicle synchronously receives the output current from both charging guns, achieving superposition of charging power. When the charging station only provides single-gun charging facilities, the vehicle can still complete charging using the single-gun method. Therefore, dual-gun charging not only meets the needs of existing charging facilities but also adapts to different charging scenarios, improving the vehicle's charging adaptability.

[0036] Because the dual-gun charging method uses two charging piles to jointly replenish vehicle power, it can make full use of the idle resources of different charging piles. When there are multiple ordinary charging piles in the charging station, there is no need to wait for the supercharging equipment to be idle; the dual-gun charging method can be used directly to replenish vehicle power. This helps to alleviate the impact of insufficient high-power charging equipment, improves the overall service capacity of the charging station, and improves the charging efficiency of new energy logistics vehicles.

[0037] Dual-gun charging also fully leverages the value of existing charging infrastructure. Currently, many completed charging stations are equipped with medium-power DC charging piles. Upgrading them all to supercharging piles would require new equipment procurement, grid modifications, and infrastructure construction, resulting in high investment costs and long construction periods. Dual-gun charging eliminates the need to alter the existing charging station structure or add large-scale supercharging equipment. Higher charging power can be achieved simply by having two ordinary charging piles output simultaneously, enhancing the capabilities of existing equipment, thereby reducing infrastructure upgrade costs and improving the economics of charging station construction.

[0038] New energy logistics vehicles typically feature large battery capacities, high operating frequencies, and short charging time requirements. During logistics transportation, the time vehicles spend charging directly impacts transportation efficiency. Adopting a dual-gun charging method allows vehicles to simultaneously utilize two charging stations, obtaining greater input power within the same timeframe. This effectively shortens the overall charging time, improves vehicle operating efficiency, and meets the rapid charging needs during logistics transportation. Furthermore, since dual-gun charging is built upon existing charging infrastructure, it can be more easily promoted and applied, enhancing the charging convenience of new energy logistics vehicles in actual use.

[0039] The combined power output of dual-gun charging stations not only increases vehicle charging speed but also expands the adaptability of new energy logistics vehicles to different charging stations. For charging stations already built but lacking supercharging equipment, dual-gun charging can still provide high-power charging services, reducing vehicle dependence on supercharging stations and improving charging availability in different regions and charging environments. For operating companies, rapid charging can be achieved without specifically searching for supercharging sites, improving vehicle operational flexibility.

[0040] During dual-gun charging, two charging stations simultaneously provide charging power to the vehicle. The vehicle's high-voltage system receives and manages the output from both charging guns in a unified manner, achieving the combined power of the two charging stations. The entire charging process fully utilizes the synchronous operation of the two charging stations, combining the output capabilities of two ordinary charging stations to form an overall charging capacity that meets the rapid energy replenishment needs of new energy logistics vehicles. This allows for the combined power of the two charging stations without requiring extensive deployment of supercharging stations, thus satisfying the demands of ultra-fast charging.

[0041] Furthermore, the dual-gun charging method is fully compatible with the existing charging network layout, does not change the overall construction mode of existing charging stations, and does not add new high-power charging equipment types. Instead, it enhances charging capacity based on existing ordinary charging piles, thus demonstrating good engineering feasibility. With the continuous increase in the number of new energy logistics vehicles, adopting the dual-gun charging method can fully utilize existing charging resources, improve the overall utilization efficiency of charging facilities, and reduce the need for new supercharging infrastructure construction. This provides a more economical, convenient, and easily promoted solution for the rapid charging of new energy logistics vehicles. Throughout the charging process, by simultaneously outputting from both guns, synchronously superimposing power, and ensuring vehicles uniformly receive charging power, the charging capacity of existing ordinary charging piles is effectively expanded. While ensuring the continued use of existing charging facilities, it improves the overall charging efficiency of new energy logistics vehicles, fully demonstrating the application value of dual-gun charging for rapid charging under existing charging infrastructure conditions.

[0042] Charging compatibility control module: The charging current output adjustment accuracy of a single charging gun is 5%, meaning there will be brief periods where the current exceeds the requested current by 5%. During charging, the charging pile controls its output based on the requested charging current sent by the vehicle. Due to the response time of the charging pile's internal power adjustment, the output current of the charging pile will not always remain completely consistent with the requested charging current during the charging start-up phase and during charging. Instead, it will fluctuate within an allowable range. Therefore, a single charging gun typically has an output current adjustment accuracy of 5%, meaning there will be brief periods where the current exceeds the requested current by 5%. This output deviation is a normal control characteristic of the charging pile and generally does not affect charging safety during single-gun charging. Therefore, traditional charging control strategies can meet the needs of single-gun charging.

[0043] Taking a typical charging condition as an example, if the requested charging current is 240A, when the charging pile's output current increases, including during the charging process or the initial charging stage, the charging pile will gradually increase the output current to near the requested value. During this process, due to differences in the power modules used by charging piles of different brands and in different regions, and slight variations in the output control precision of the power modules, the actual output current of each charging pile may deviate slightly from the requested charging current. Typically, the output current range for each pile is within 5%. That is to say, when the requested charging current is 240A, the output current of a single charging pile may change within the allowable error range. This change is part of the normal output adjustment process of the charging pile and does not indicate any abnormality in the charging equipment.

[0044] With a dual-gun charging method, two charging guns are connected to two charging stations, each controlling its output according to the vehicle's requested charging current. Since each charging station has its own output adjustment error, when both stations operate simultaneously, the output deviations from each station are superimposed. Therefore, the combined effect of the dual guns causes the battery charging current to exceed the requested current by more than 10%. In other words, although the output deviation of a single charging station is still controlled within 5%, when both stations operate simultaneously, the two output currents work together on the battery, resulting in a larger deviation between the actual charging current and the requested charging current.

[0045] For example, when the requested charging current is 240A, in dual-gun charging mode, both charging stations may experience a certain increase in output, resulting in an actual dual-gun output of 240-252A. This actual output current is the result of the combined output errors of both charging stations, not an anomaly in one charging station alone, but rather a normal output characteristic that may occur under dual-gun charging conditions. Because dual-gun charging introduces the factor of the combined output errors of the two charging stations, using a single-gun charging control strategy could easily lead to misjudgments.

[0046] In traditional single-gun charging control, charging management typically establishes an overcurrent protection threshold based on the requested charging current. When the charging current exceeds the requested value by a certain percentage, an overcurrent is considered to have occurred, and protective measures such as reducing the charging current or stopping charging are taken. This strategy is based on single-gun charging and only considers the output error of a single charging station, thus meeting the needs of single-gun charging. However, in dual-gun charging, because two charging stations output simultaneously, the adjustment deviations generated by the two charging stations will be superimposed. Even if each charging station is working normally, the actual charging current of the battery may exceed the fault threshold set for single-gun charging. If the original control method is still used, the overcurrent protection will be frequently triggered, preventing the vehicle from completing dual-gun charging normally, reducing the compatibility of dual-gun charging, and affecting the adaptation effect of charging stations of different brands and regions.

[0047] To address the issue of overlapping output errors from the two charging stations during dual-gun charging, the battery charging overcurrent threshold has been adjusted. The threshold has been changed from reducing the charging current request when the actual charging current exceeds 5% to reducing it when it exceeds 10%. In other words, when the actual battery charging current exceeds the requested charging current by less than 10%, it is not immediately considered a charging fault. Instead, it is assumed to be within the normal output error range of dual-gun charging, and charging continues. Simultaneously, a strategy to reduce the requested charging current is activated, gradually lowering the charging station's output current until the actual battery charging current returns to a reasonable range.

[0048] By adopting the above method, the charging control no longer directly judges according to the single-gun charging standard, but fully considers the output characteristics of dual-gun charging and handles charging currents that slightly exceed the requested value. This ensures that the dual-gun charging process can continue, while avoiding frequent charging interruptions due to differences in the output adjustment accuracy of charging piles from different brands and regions, thus improving the stability and success rate of dual-gun charging.

[0049] To further ensure the safety of power battery charging, in addition to adjusting the battery charging overcurrent threshold, a safety fallback is also set up. When the output current of both charging stations exceeds the requested value by 20%, charging will be stopped to protect battery safety. This safety fallback strategy is used to deal with abnormal output situations. When the output current of both charging stations continues to increase and the actual charging current has significantly exceeded the normal adjustment error range, charging will not continue; instead, charging will be immediately stopped to cut off the charging process and prevent continuous overcurrent from adversely affecting the power battery, high-voltage circuit, and charging equipment.

[0050] A safety fallback strategy and a charging overcurrent threshold adjustment strategy together constitute a dual-layer protection mechanism. The first layer of protection addresses normal output errors during dual-gun charging by increasing the charging overcurrent adjustment threshold to improve dual-gun charging compatibility. The second layer of protection addresses abnormal output states; when the dual-gun output current exceeds the requested value by 20%, charging is immediately stopped to protect battery safety. Through these two different levels of control strategies, the safety requirements for power battery charging are maintained while ensuring dual-gun charging compatibility.

[0051] Throughout the dual-gun charging process, the charging management system continuously monitors the requested charging current and the actual charging current of the battery, and determines in real time whether the current charging status is within the allowable range. When the actual charging current is within 10% of the requested value, it is considered a normal charging state; when the actual charging current exceeds 10% of the requested value, a reduction in the charging current request is executed; when the actual charging current continues to increase and exceeds 20% of the requested value, a stop charging control is executed to ensure that the power battery always operates within a safe and allowable range.

[0052] Because different brands of charging piles use power modules manufactured by different companies, and charging piles in different regions may also employ different control strategies, there are certain differences in output current response speed, control accuracy, and dynamic adjustment characteristics. During dual-gun charging, the output characteristics of both charging piles work together on the power battery, making short-term current fluctuations more likely. Without a new overcurrent control strategy specifically designed for dual-gun charging, compatibility issues can easily arise between charging piles of different brands and in different regions, affecting normal vehicle charging.

[0053] By combining adjustments to the charging overcurrent threshold with a safety fallback mechanism, the system can fully accommodate the output characteristics of charging piles from different brands and regions, improving its adaptability to various charging devices during dual-gun charging. Current fluctuations within the normal output error range are no longer directly identified as charging faults, but charging is allowed to continue; abnormal outputs exceeding the safety allowable range are promptly stopped to ensure the safety of the power battery.

[0054] In summary, the actual dual-gun output currents are all within the BMS fault threshold setting range, allowing for normal charging. This means that during dual-gun charging, the actual charging current resulting from the normal output errors of the two charging piles remains within the readjusted BMS fault threshold range. This prevents accidental triggering of overcurrent faults due to normal output deviations and allows for timely protective measures in case of abnormal output. This achieves a balance between dual-gun charging compatibility and power battery safety, improving the stability and reliability of dual-gun charging for new energy logistics vehicles, as well as charging compatibility between charging piles of different brands and in different regions.

[0055] Voltage Request Adjustment Module: During charging, after the vehicle completes communication with the charging pile, it continuously receives communication messages sent by the charging pile and obtains the maximum output voltage parameters that the charging pile can provide. When it detects that the charging pile sends a CML (Content Management Line) message indicating a maximum output of 750V, if the battery's maximum voltage exceeds this value, the BMS does not set a charging stop. Instead, it requests the charging pile's output voltage at 750V. When the actual voltage reaches 750V, charging stops. By identifying the charging pile's maximum output voltage and dynamically adjusting the requested voltage based on the charging pile's actual output capacity, the vehicle can continue to use the current charging pile to complete charging, instead of immediately ending charging when insufficient output capacity is detected. This improves the vehicle's adaptability to charging piles with different output capacities and its charging compatibility.

[0056] During the charging process of new energy vehicles, the maximum output voltage of charging piles is not entirely consistent. Different brands, models, and regions of charging piles have varying maximum output voltages. Some charging piles can provide a maximum output voltage of 750V, some can provide 1000V, and others have other different output capabilities. Throughout the charging process, as the battery charge increases, the battery terminal voltage continuously rises. Therefore, whether the battery can be fully charged depends not only on the battery's own parameters but also directly on the maximum output voltage that the charging pile can provide.

[0057] For new energy logistics vehicles using high-voltage power batteries, the power batteries have a wide operating voltage range. Initially, the battery voltage is relatively low, but as charging continues, the internal charge of the power battery increases, and the battery terminal voltage rises accordingly, gradually approaching the full charge voltage. If the charging station can provide a sufficiently high output voltage, the vehicle can continuously charge according to the actual needs of the power battery until it reaches a full charge. If the maximum output voltage of the charging station is lower than the voltage required for a full charge, the charging process will be limited by the charging station's output capacity.

[0058] To illustrate the actual charging process, a typical power battery is used as an example. A typical battery has a 202kWh capacity, a rated voltage of 733V, and a voltage range of 548V-844V. As the charge level steadily increases, the voltage gradually rises. That is, in the initial stage of charging, the battery terminal voltage is at a low level. As charging continues, the battery's state of charge increases, and the battery terminal voltage gradually rises from 548V, eventually approaching the full charge voltage of 844V. Throughout the charging process, the voltage fluctuation of the power battery is a normal charging characteristic; therefore, the requested charging voltage needs to be matched to the actual state of the power battery.

[0059] When the vehicle detects a maximum output voltage of 750V in the CML message sent by the charging pile, it first checks whether the maximum charging voltage of the power battery exceeds 750V. If the maximum charging voltage of the power battery is higher than 750V, it indicates that the current output capacity of the charging pile is insufficient to support a full charge of the power battery. In this case, charging is not terminated directly, nor is a matching fault immediately reported due to insufficient output capacity of the charging pile. Instead, the current charging process continues. The BMS does not set a charging stop function, but requests the charging pile output voltage according to 750V, that is, it adjusts the requested voltage sent to the charging pile to 750V, so that the charging pile continuously outputs voltage according to its maximum output capacity.

[0060] During the 750V charging request process, the power battery continuously receives charge, and its voltage gradually increases with charging time. While the actual battery voltage has not yet reached 750V, the charging process continues normally, with the charging station maintaining a 750V output voltage. Charging stops when the actual voltage reaches 750V. This termination is not due to an abnormality in the charging process, but rather because the power battery has reached the maximum output voltage that the charging station can provide, and further charging cannot increase the battery voltage; therefore, the current charging process ends.

[0061] The above control method makes full use of the existing output capacity of the charging pile. When the output capacity of the charging pile is insufficient to support the full charge of the power battery, the vehicle is still allowed to continue to complete the charging process that can be achieved at present, thereby improving the vehicle's energy replenishment capability. Instead of directly terminating the charging because the maximum output voltage of the charging pile is lower than the full charge voltage of the power battery, the vehicle's compatibility with charging piles of different specifications is improved.

[0062] For example, if the charging station's matching parameters are 750V, the battery will not fully charge. If the State of Charge (SOC) is 60% and the battery voltage exceeds 750V, the charging will stop at 60% SOC. In other words, when the battery's state of charge increases to approximately 60%, the battery's terminal voltage is close to or reaches 750V, but the current charging station's maximum output voltage can only provide 750V. Therefore, the battery cannot continue to increase its terminal voltage to complete the subsequent charging, and the charging process ends, with the vehicle maintaining its current SOC. Although the battery is not fully charged, it has fully utilized the current charging station's output capacity to achieve maximum energy replenishment, avoiding the inability to continue charging at the beginning due to voltage mismatch.

[0063] In the above situation, the inability of the power battery to further increase its State of Charge (SOC) is not due to a fault in the power battery or an abnormality in the charging process, but rather a normal result caused by the limitation of the maximum output capacity of the charging station. The vehicle can still complete partial charging, improving its driving range, and at the same time, it improves the compatibility between different charging stations, enabling the vehicle to utilize more existing charging resources for charging.

[0064] When the charging station has a higher output capacity, the charging control method remains consistent with the power battery's requirements. For example, if the charging station outputs 1000V and the BMS requests a voltage of 844V, charging will stop when fully charged. Since the charging station can provide a maximum output voltage of 1000V, while the power battery's maximum charging voltage is only 844V, the charging station's output capacity already meets all the power battery's charging needs. In this case, the BMS sends a voltage request to the charging station according to the power battery's maximum charging voltage of 844V. The charging station continues charging according to the 844V request, and the power battery voltage gradually increases from the current voltage to 844V. Once the power battery reaches full charge, charging ends, achieving a fully charged power battery.

[0065] This demonstrates that charging stations with different output capabilities result in different charging outcomes. When the maximum output voltage of the charging station is lower than the full-charge voltage of the battery, the vehicle continues charging according to the maximum output voltage of the charging station, eventually reaching the highest charging state supported by the current charging station. When the maximum output voltage of the charging station is higher than or meets the full-charge requirement of the battery, charging is requested according to the maximum charging voltage of the battery, ultimately completing a full charge. Throughout the entire charging process, the requested voltage always matches the output capability of the charging station, ensuring that the charging process remains executable at all times.

[0066] With the above-mentioned charging voltage control method, the charging control no longer uses a single fixed requested voltage, but dynamically adjusts the requested voltage according to the maximum output voltage sent by the charging pile. When the output capacity of the charging pile is insufficient, charging does not stop, but continues to complete the energy replenishment according to the current maximum output voltage; when the output capacity of the charging pile meets the needs of the power battery, the entire charging process is completed according to the full charging voltage of the power battery. This can make full use of 750V-level charging piles to replenish vehicle energy, and also make full use of the high-voltage charging capacity of 1000V-level charging piles.

[0067] Throughout the charging process, by continuously identifying CML messages sent by the charging pile, obtaining the maximum output voltage of the charging pile in real time, dynamically adjusting the BMS request voltage, and executing corresponding charging strategies according to different output capabilities, the vehicle can be compatible with charging piles of different output voltage platforms. When the output capacity of the charging pile is limited, the vehicle can continue to complete the current charging without prematurely exiting the charging process; when the output capacity of the charging pile meets the needs of the power battery, the power battery can be fully charged. This method improves the charging compatibility of new energy logistics vehicles with charging piles of different voltage platforms such as 750V and 1000V without changing the charging characteristics of the power battery, making full use of existing charging infrastructure and improving the vehicle's charging success rate and actual energy replenishment efficiency.

[0068] This invention, by setting an overcurrent threshold control strategy for dual-gun charging of new energy light trucks, can effectively meet the adaptation needs of output deviation superposition during dual-gun charging of different brands and regions. In dual-gun charging mode, the two charging piles output current separately. Due to differences in the adjustment accuracy of the power modules of different charging piles, the output deviation of a single charging pile may occur within a certain range. When both guns work simultaneously, the output deviations of the two charging piles will superimpose, causing the actual charging current to exceed the requested current. By adjusting the overcurrent threshold under dual-gun charging conditions, the charging system can adapt to the superposition of output current changes between the two guns. This reduces the false charging stoppage caused by normal output deviations of the charging piles while ensuring battery safety, improves the compatibility of new energy light trucks with charging piles of different brands and regions, and enables stable and efficient dual-gun rapid energy replenishment using existing charging facilities.

[0069] This invention improves the charging compatibility of new energy light trucks with charging piles of different output voltage levels by actively adjusting the requested voltage value sent to the charging pile based on its output voltage. During charging, the maximum output voltage provided by the charging pile is identified and adjusted according to the actual full-charge voltage requirement of the power battery. When the charging pile's output voltage cannot meet the battery's full-charge requirement, charging is not stopped directly; instead, a request is made for the maximum output voltage that the charging pile can provide, allowing the vehicle to continue the current charging process. When the charging pile's output voltage can meet the battery's full-charge requirement, a request is made for the full-charge voltage of the battery, achieving a full charge. Through this dynamic voltage adaptation method, the charging success rate of new energy light trucks is improved in charging environments with different voltage platforms, expanding the vehicle's charging applicability and enhancing charging convenience and infrastructure utilization efficiency.

[0070] The foregoing has only described certain exemplary embodiments of the present invention by way of illustration. Undoubtedly, those skilled in the art can modify the described embodiments in various ways without departing from the spirit and scope of the present invention. Therefore, the foregoing drawings and descriptions are illustrative in nature and should not be construed as limiting the scope of protection of the claims of the present invention.

Claims

1. A dual-gun charging compatibility strategy and a new energy logistics vehicle, characterized in that, This includes a dual-gun input module, a charging compatibility control module, and a voltage request adjustment module. With the dual-gun access module, the new energy logistics vehicle enters the dual-gun charging state, using two charging guns to connect to the charging piles simultaneously for charging. The two charging piles output charging power simultaneously, and the output currents of the two charging guns are superimposed to obtain the actual charging current of the battery. The actual charging current of the battery is then used as the data basis for subsequent charging control. The charging compatibility control module performs charging current compatibility control based on the actual charging current of the battery. When the actual charging current of the battery exceeds 10% of the requested charging current, the requested charging current is reduced; when the actual charging current of the battery exceeds 20% of the requested charging current, charging is stopped to protect battery safety. Dual-gun charging is maintained as long as the actual charging current of the battery does not exceed 20% of the requested charging current. After completing the charging current compatibility control, the voltage request adjustment module obtains the maximum output voltage sent by the charging pile. When the maximum output voltage is lower than the maximum charging voltage of the battery, the battery management system requests the charging pile to output voltage according to the maximum output voltage and stops charging when the actual charging voltage reaches the maximum output voltage. When the maximum output voltage reaches or exceeds the maximum charging voltage of the battery, the battery management system requests the charging pile to output voltage according to the maximum charging voltage of the battery and stops charging when the battery is fully charged.

2. The dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 1, characterized in that, Dual-gun charging means that the new energy light truck is connected to two charging piles at the same time. The charging current output from the two charging piles is obtained through the two charging guns respectively, and the charging current output from the two charging guns is superimposed to form the actual charging current of the vehicle. The two charging piles output power independently, and the vehicle completes high-power energy replenishment based on the superimposed charging power output from the two guns. This improves the overall charging power of the new energy light truck and meets the needs of rapid energy replenishment without the need to configure supercharging piles.

3. The dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 2, characterized in that, In dual-gun charging mode, the output current of the two charging piles is obtained respectively, and the actual charging current of the battery is determined according to the output current adjustment characteristics of the two charging piles. When there is an adjustment deviation in the output current of a single charging pile, the output current of two charging piles is superimposed for judgment, so that the charging control can adapt to the output current deviation caused by the difference in the adjustment accuracy of the power modules of charging piles of different brands and regions, thereby improving the compatibility between the vehicle and the charging pile during dual-gun charging.

4. The dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 1, characterized in that, During the charging current compatibility control process, a first current control threshold and a second current protection threshold are set. When the actual charging current of the battery exceeds the first current control threshold of the requested charging current, the requested charging current is reduced to reduce the actual output current of the charging pile. When the actual charging current of the battery exceeds the second current protection threshold, charging is stopped and charging overcurrent fault information is output to ensure the charging safety of the power battery while improving the compatibility of dual-gun charging.

5. A dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 4, characterized in that, The first current control threshold corresponds to 10% of the requested charging current. When the actual charging current of the battery exceeds 10% of the requested charging current, the requested charging current value is actively reduced to avoid accidental charging stop caused by the superposition of the output adjustment deviations of the two charging piles. The second current protection threshold corresponds to 20% of the requested charging current. When the output current value of the dual guns exceeds 20% of the requested charging current, charging is stopped to protect the power battery and the vehicle's high-voltage charging circuit.

6. The dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 1, characterized in that, During the charging voltage adaptation control process, the maximum output voltage information sent by the charging pile is obtained, and the maximum output voltage of the charging pile is compared with the maximum charging voltage of the power battery. When the maximum output voltage of the charging pile is lower than the maximum charging voltage of the power battery, the requested voltage sent to the charging pile is adjusted according to the maximum output voltage of the charging pile to enable the vehicle to continue charging. When the maximum output voltage of the charging pile meets the maximum charging voltage requirement of the power battery, the requested voltage is sent according to the maximum charging voltage of the power battery.

7. A dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 6, characterized in that, When the maximum output voltage sent by the charging pile is detected to be 750V, and the maximum voltage of the power battery exceeds 750V, the vehicle does not stop the charging process, but sends a request voltage to the charging pile according to 750V, so that the charging pile can charge according to the 750V output voltage; when the actual voltage of the power battery reaches 750V, the charging process ends, so as to improve the vehicle's adaptability to charging piles with voltages lower than the full charge voltage of the power battery.

8. A dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 6, characterized in that, When it is detected that the maximum output voltage of the charging pile exceeds the full charge voltage of the power battery, a maximum voltage request value is sent to the charging pile according to the full charge voltage of the power battery, so that the charging pile outputs voltage according to the charging needs of the power battery; when the power battery voltage gradually rises to the full charge voltage, the charging process ends, the power battery is fully charged, and the utilization efficiency of high voltage level charging piles is improved.

9. A dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 1, characterized in that, The new energy light truck includes a power battery, a battery management system, and a dual-gun charging interface. The battery management system is used to obtain dual-gun charging status information, collect charging pile output current and charging pile output voltage information, and adjust the requested charging current and requested charging voltage according to the obtained information to achieve current compatibility control during dual-gun charging and charging adaptation control between charging piles with different output voltages.

10. A dual-gun charging compatibility strategy and new energy logistics vehicle according to claim 1, characterized in that, The charging control method achieves compatible charging for new energy light trucks in different brands, regions, and charging pile environments with different output capabilities by superimposing the output power of the dual guns, current deviation compensation control, and active output voltage adaptation control. In particular, by adjusting the dual-gun charging overcurrent protection strategy, it avoids abnormal charging stoppage caused by the superposition of charging pile output deviations, and by adjusting the requested voltage, it avoids charging failure due to insufficient charging pile voltage, thereby improving the charging stability and energy replenishment efficiency of new energy light trucks.

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