A charging voltage line loss compensation control method and system based on BMS closed-loop feedback and a medium

Abstract

The application relates to a charging voltage line loss compensation control method and system based on BMS closed-loop feedback and a medium, and relates to the technical field of charging control. The charging voltage line loss compensation control method comprises the following steps: a BMS at a battery end collects a total voltage of a battery pack, generates a transparent data packet, and transmits the transparent data packet to a charger controller; the charger controller receives and analyzes the transparent data packet, extracts an actual total voltage, and obtains an output end voltage inside the charger; according to the actual total voltage and the output end voltage, a real-time line loss voltage drop is calculated, an output correction voltage is generated in combination with a line loss correction mechanism; the closed-loop precise control of the charging voltage is realized through the line loss correction mechanism, the influence of the line loss on the charging accuracy is eliminated, capacity attenuation of the battery caused by undercharging is avoided, and a safety risk caused by overvoltage is avoided.

Description

Technical Field

[0001] This application relates to the field of charging control technology, and in particular to a charging voltage line loss compensation control method, system and medium based on BMS closed-loop feedback. Background Technology

[0002] During high-current AGV charging, a significant voltage drop (line loss) occurs in the connection lines (cables and brush contacts) between the charger and the battery. In existing technologies, the charger typically performs constant voltage control based solely on its own output voltage, while the battery management system (BMS) determines whether the battery is fully charged based on the actual voltage at the battery terminals.

[0003] Existing patents disclose an electric vehicle charger charging system and method. The charging system includes a DC module and a charger management system (CMS). The charger management system (CMS) includes a charger battery management system (CBMS) and a charger charging management system (CCMS). The charger battery management system (CBMS) is connected to the charger charging management system (CCMS) and the DC module via CAN bus 1. The charger battery management system (CBMS) is also connected to the vehicle battery management system (BMS) via CAN bus 2. Based on the collected data from the vehicle battery management system (BMS) and the current charger charging voltage and current, the system changes from passive to active charging. According to a certain strategy, it performs logical calculations and outputs a more reasonable charging voltage and charging current within the requirements of the vehicle battery management system (BMS), thus solving the safety hazards of the existing passive charging mode of the charger.

[0004] The existing technical solutions mentioned above have the following drawbacks: 1. Due to line loss, the voltage displayed by the charger is higher than the actual voltage received by the battery, and the battery is in a state of undercharging for a long time and cannot reach full capacity; 2. When the BMS determines that the cutoff voltage requirement has been reached and stops charging, the charger is mistakenly judged as abnormal because the output voltage is not up to standard, resulting in charging interruption or error. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the purpose of this application is to provide a charging voltage line loss compensation control method, system, and medium based on BMS closed-loop feedback. Through the line loss correction mechanism, the charging voltage is controlled in a closed loop with precision, eliminating the impact of line loss on charging accuracy, avoiding capacity decay caused by undercharging, and safety risks caused by overvoltage.

[0006] This was achieved using the following technical solutions: In a first aspect, this application provides a charging voltage line loss compensation control method based on BMS closed-loop feedback, including: The battery-side BMS collects the total voltage of the battery pack, generates and transmits transparent data packets to the charger controller; The charger controller receives and parses the transparent data packet, extracts the actual total voltage, and obtains the output voltage inside the charger. Based on the actual total voltage and the output voltage, the real-time line loss voltage drop is calculated, and the output correction voltage is generated by combining the line loss correction mechanism.

[0007] By adopting the above technical solution, the total voltage of the battery pack is collected in real time by the BMS and transmitted to the charger controller. The controller analyzes and obtains the actual total voltage, and at the same time samples the output voltage inside the charger. Based on the difference between the two, the real-time line loss voltage drop is dynamically calculated, and the output voltage is adaptively compensated based on the closed-loop feedback line loss correction algorithm to generate an accurate output correction voltage. This effectively offsets the voltage deviation caused by the change in charging line impedance, ensuring that the charging voltage at the battery end is always consistent with the target value, and significantly improving charging accuracy, battery cycle life and system safety.

[0008] This application further specifies that: the battery-side BMS collects the total voltage of the battery pack, generates and transmits a transparent data packet to the charger controller, including: The battery-side BMS samples the voltage between the positive and negative terminals of the battery pack through a voltage sampling circuit to obtain the total voltage of the battery pack. The battery-side BMS filters and denoises the total voltage of the battery pack according to the sampling period to obtain the standard total voltage. If the standard total voltage is within the preset effective voltage range, the current standard total voltage is determined to be the actual total voltage, and a transparent data packet is generated in conjunction with the preset communication protocol. The communication interface of the battery-side BMS transmits transparent data packets to the charger controller.

[0009] By adopting the above technical solution, the battery-side BMS uses a mean filtering algorithm to smooth and denoise the voltage sampling signal, and performs threshold judgment based on the effective voltage range to filter reliable data. Then, it encapsulates and generates transparent data packets according to the communication protocol and transmits them to the charger controller, thus realizing accurate acquisition and efficient transmission of the total battery pack voltage.

[0010] This application further specifies that: the charger controller receives and parses the transparent data packet, extracts the actual total voltage, and obtains the output terminal voltage inside the charger, including: The charger controller receives transparent data packets through the communication interface and temporarily stores them in the buffer. In the buffer, frame header verification, frame trailer verification, and checksum verification are performed on the transparent data packets according to the communication protocol. If all verifications are successful, the transparent data packet is parsed according to the data packet format to locate and extract the payload; The charger controller converts the payload according to the byte order and data type to obtain the actual total voltage; The charger controller detects the charger output terminal through a voltage sampling circuit to obtain the analog voltage signal at the output terminal; The charger controller filters and transforms the analog voltage signal at the output terminal to obtain the output voltage.

[0011] By adopting the above technical solution, the controller receives and verifies the transparent data packets, and after verifying the frame header, frame tail and check code, it parses the payload and converts it according to byte order to obtain the actual total voltage. At the same time, the sampling circuit detects the analog signal at the output end, and obtains the output voltage through filtering and transformation. This ensures the accuracy of the data and realizes the accurate acquisition of the output voltage, providing a reliable input for the calculation of line loss voltage drop, thereby significantly improving the accuracy and stability of charging control.

[0012] This application is further configured to: calculate the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generate the output correction voltage in conjunction with the line loss correction mechanism, including: Match the sampling timestamps of the actual total voltage and the output voltage, and calculate the timestamp difference. If the timestamp difference is greater than or equal to the preset synchronization tolerance threshold, it is determined to be voltage data at different times, and the sampling timestamp of the output voltage is interpolated and calculated to the sampling timestamp of the actual total voltage. If the timestamp difference is less than the synchronization tolerance threshold, it is determined to be voltage data at the same time, and the initial line resistance reference value is calculated based on the preset calibration current. For the actual total voltage With output voltage Perform the difference calculation to obtain the current line loss voltage drop value. ; Based on the total resistance of the charging circuit and the initial line resistance reference value, calculate the dynamic offset of the line resistance and the line resistance ratio. Based on the dynamic offset of the line resistance and the thermal drift coefficient of the line resistance, the current line loss voltage drop value is corrected to obtain the temperature-compensated line loss voltage drop value: , in, V loss_comp To compensate for line loss voltage drop, R ref This is the initial reference value for the line resistance. ΔR This represents the dynamic offset of the line resistance. α This is the thermal drift coefficient of the line resistance. ΔT This refers to the change in temperature. If the temperature compensation line loss voltage drop is less than the preset line loss voltage drop safety threshold and the line resistance ratio is less than the preset resistance drift threshold, the charging circuit is determined to be normal, and a corresponding correction strategy is matched according to the charging status. According to the preset fixed voltage value By combining the temperature-compensated line loss voltage drop value, the output voltage is corrected to obtain the corrected output voltage. for: ; According to the preset charging curve target value By combining the temperature-compensated line loss voltage drop value, a corrected output voltage is generated. for: ; If not, it is determined that the charging circuit is abnormal, triggering a line loss abnormality alarm and reducing power output.

[0013] By adopting the above technical solution, the real-time difference between the actual total battery voltage sampled by the BMS and the output voltage of the charger is used to eliminate time delay errors by combining the sampling timestamp synchronization judgment and interpolation alignment algorithm. The initial line resistance reference value is calculated using the calibration current, and line resistance thermal drift compensation is introduced to correct the line loss fluctuation caused by dynamic temperature rise. According to the segmented adaptive strategy of using fixed voltage correction in the pre-charge / constant current stage and charging curve target value correction in the fast charge / saturation stage, the corrected output voltage is accurately generated under the premise of ensuring that the temperature compensation line loss value is lower than the safety threshold and the resistance ratio is stable, thereby improving the environmental adaptability, control accuracy and system safety of the charging process.

[0014] Secondly, this application also provides a charging voltage line loss compensation control system based on BMS closed-loop feedback, which adopts the following technical solution: A charging voltage line loss compensation control system based on BMS closed-loop feedback is used to implement a charging voltage line loss compensation control method, including: The data acquisition and transmission module is used by the battery-side BMS to acquire the total voltage of the battery pack, generate and transmit transparent data packets to the charger controller. The receiving and parsing module is used by the charger controller to receive and parse the transparent data packets, extract the actual total voltage, and obtain the output voltage inside the charger. The line loss correction module is used to calculate the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generate the output correction voltage in conjunction with the line loss correction mechanism.

[0015] By adopting the above technical solution, the total battery voltage is collected by the BMS and transmitted to the charger controller. After parsing and extracting the actual total voltage, the difference between the actual total voltage and the charger output voltage is calculated in real time. Combined with the sampling timestamp synchronization and thermal drift compensation algorithm, the line loss voltage drop is dynamically corrected, realizing adaptive closed-loop adjustment of the output correction voltage, which improves the voltage control accuracy and system safety of the charging process under complex working conditions.

[0016] Thirdly, this application also provides a storage medium storing at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, at least one program, code set, or instruction set is loaded and executed by a processor to implement the charging voltage line loss compensation control method based on BMS closed-loop feedback as described above.

[0017] In summary, the beneficial technical effects of this application are as follows: By collecting the total battery voltage through the BMS and transmitting it to the charger controller, the actual total voltage is extracted and then the difference between the actual total voltage and the charger output voltage is calculated in real time. Combined with sampling timestamp synchronization and thermal drift compensation algorithm, the line loss voltage drop is dynamically corrected, and the adaptive closed-loop adjustment of the output correction voltage is realized, which improves the voltage control accuracy and system safety of the charging process under complex working conditions. The line loss correction mechanism enables closed-loop precise control of the charging voltage, eliminating the impact of line loss on charging accuracy, avoiding capacity decay caused by undercharging, and safety risks caused by overvoltage. Attached Figure Description

[0018] Figure 1 This is a flowchart illustrating the charging voltage line loss compensation control method in this application; Figure 2 This is a flowchart illustrating step S2 in this application; Figure 3 This is a flowchart illustrating step S3 in this application; Figure 4 This is a schematic diagram of the charging voltage line loss compensation control system in this application. Detailed Implementation

[0019] The present application will be further described in detail below with reference to the accompanying drawings.

[0020] This application discloses a charging voltage line loss compensation control method based on BMS closed-loop feedback, including: S1: The battery-side BMS collects the total voltage of the battery pack, generates and transmits transparent data packets to the charger controller; S2: The charger controller receives and parses the transparent data packet, extracts the actual total voltage, and obtains the output voltage inside the charger. S3: Calculate the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generate the output correction voltage by combining the line loss correction mechanism.

[0021] In this embodiment, in the wireless charging application of lithium battery packs in an industrial AGV (Automated Guided Vehicle), the AGV's onboard battery management system (BMS) collects the total voltage (nominal voltage 25.2V) of the 24V lithium battery pack at a frequency of 1Hz, and generates a transparent data packet containing the battery pack ID, temperature, current, and total voltage via CAN messages. This data packet is then sent to the charger controller via a charging gun connection cable (5 meters long, 2.5mm² cross-sectional area). The charger controller receives and parses the data packet, extracts the actual total voltage of the battery (e.g., 23.8V), and simultaneously obtains the voltage at the charger's internal output terminal (e.g., 24.2V). It calculates the real-time line loss voltage drop ΔV = 24.2V - 23.8V = 0.4V. This line loss value is related to the charging current (50A) and the cable loop resistance. The system incorporates a preset line loss correction mechanism. When the line loss voltage drop ΔV ≤ 0.2V, the line contact is considered good and no compensation is needed. When 0.2V < ΔV ≤ 0.8V, it is considered normal cable impedance loss, and the system adjusts the output voltage to 24.2V + (24.2V - 23.8V) = 24.6V to offset the cable voltage drop and restore the actual battery voltage to the target value. When ΔV > 0.8V, it is considered a cable abnormality (such as connector oxidation or excessively thin cable), and the system triggers charging stop and reports an alarm. At the same time, this compensation mechanism updates every 100ms and can be dynamically adjusted according to changes in charging current. For example, when the current drops from 50A to 10A, the line loss voltage drop drops from 0.4V to 0.08V, and the compensation amount is automatically reduced to prevent overcharging. In this way, through the closed-loop feedback of the BMS, the terminal voltage output by the charger is always adjusted after line loss compensation, ensuring that the battery pack is accurately charged at the target voltage (such as 24V) in each stage of constant current-constant voltage charging. This effectively avoids undercharging or overcharging caused by cable voltage drop in the traditional open-loop method, and improves charging efficiency and battery cycle life.

[0022] Preferably, step S1 includes: The battery-side BMS samples the voltage between the positive and negative terminals of the battery pack through a voltage sampling circuit to obtain the total voltage of the battery pack. The battery-side BMS filters and denoises the total voltage of the battery pack according to the sampling period to obtain the standard total voltage. If the standard total voltage is within the preset effective voltage range, the current standard total voltage is determined to be the actual total voltage, and a transparent data packet is generated in conjunction with the preset communication protocol. The communication interface of the battery-side BMS transmits transparent data packets to the charger controller.

[0023] In this embodiment, the battery-side BMS acquires the total voltage of the battery pack in real time through a voltage sampling circuit. This process typically uses a high-precision analog-to-digital converter to sample the voltage between the positive and negative terminals of the battery pack, with the sampling period matching the control period of the BMS.

[0024] The BMS filters the acquired raw voltage data to eliminate sampling noise and instantaneous fluctuations. Simultaneously, the BMS compares the filtered voltage values ​​with a preset effective range to determine if the acquired values ​​are reasonable.

[0025] The BMS encapsulates the verified voltage value into a transparent data packet according to the communication protocol agreed upon by the charger controller or the system. The transparent data packet typically contains the following fields: frame header, destination address, data length, payload, and checksum. The payload is filled with the voltage value and the data acquisition timestamp.

[0026] The encapsulated transparent data packet is sent through the BMS communication interface. After receiving the data packet, the charger controller checks the data integrity using a checksum.

[0027] The charger controller parses the data packets according to the agreed communication protocol, extracting the voltage value and the acquisition timestamp. The controller then performs a validity check on the parsed voltage value.

[0028] The charger controller stores the received total battery pack voltage value in an internal variable and updates the corresponding status flag. Based on the voltage value, the controller adjusts the charging strategy and generates corresponding status feedback information.

[0029] If the charger controller determines that the current voltage value exceeds the preset range, it triggers an exception handling procedure, sends an error status to the BMS, and performs corresponding actions according to the error level. If the voltage value is determined to be normal, the charging process continues.

[0030] Reference Figure 2 Preferably, step S2 includes: S21: The charger controller receives the transparent data packet through the communication interface and temporarily stores it in the buffer; S22: In the buffer, perform frame header verification, frame trailer verification, and checksum verification on the transparent data packets according to the communication protocol. If all verifications are successful, the transparent data packet is parsed according to the data packet format to locate and extract the payload; S23: The charger controller converts the payload according to the byte order and data type to obtain the actual total voltage; S24: The charger controller detects the output terminal of the charger through the voltage sampling circuit to obtain the analog voltage signal of the output terminal; S25: The charger controller filters and transforms the analog voltage signal at the output terminal to obtain the output voltage.

[0031] In this embodiment, the charger controller continuously listens for transparent data packets from the battery management system (BMS) through its communication interface. When a data packet is received, the controller temporarily stores it in a receive buffer, preparing it for subsequent parsing processing.

[0032] The controller performs integrity checks on the received data packets according to the agreed communication protocol, including frame header verification, frame trailer verification, and checksum verification. If the data packet passes the integrity check, it proceeds to the next step of the parsing process.

[0033] The controller locates the starting position of the payload according to the data packet format agreed upon in the protocol, and extracts the valid information fields carried therein.

[0034] The controller extracts the actual total voltage value of the battery pack from the payload according to a predefined bit sequence and data type definition. This process involves byte order conversion and unit conversion, transforming the raw data into actual physical quantities.

[0035] The controller synchronously extracts the acquisition timestamp and battery status information from the data packet to ensure the correspondence between the voltage data and the acquisition time.

[0036] The charger controller collects the charger output voltage in real time through an internal voltage sampling circuit (such as a resistor divider network in conjunction with an ADC sampling channel).

[0037] The controller performs digital filtering on the original AD values ​​obtained from sampling, and converts the filtered values ​​into actual physical quantities by combining the transformation coefficients of the voltage sampling circuit.

[0038] Reference Figure 3 Preferably, step S3 includes: Match the sampling timestamps of the actual total voltage and the output voltage, and calculate the timestamp difference. If the timestamp difference is greater than or equal to the preset synchronization tolerance threshold, it is determined to be voltage data at different times, and the sampling timestamp of the output voltage is interpolated and calculated to the sampling timestamp of the actual total voltage. If the timestamp difference is less than the synchronization tolerance threshold, it is determined to be voltage data at the same time, and the initial line resistance reference value is calculated based on the preset calibration current. For the actual total voltage With output voltage Perform the difference calculation to obtain the current line loss voltage drop value. ; Based on the total resistance of the charging circuit and the initial line resistance reference value, calculate the dynamic offset of the line resistance and the line resistance ratio. Based on the dynamic offset of the line resistance and the thermal drift coefficient of the line resistance, the current line loss voltage drop value is corrected to obtain the temperature-compensated line loss voltage drop value: , in, V loss_comp To compensate for line loss voltage drop, R ref This is the initial reference value for the line resistance. ΔR This represents the dynamic offset of the line resistance. α This is the thermal drift coefficient of the line resistance. ΔT This refers to the change in temperature. If the temperature compensation line loss voltage drop is less than the preset line loss voltage drop safety threshold and the line resistance ratio is less than the preset resistance drift threshold, the charging circuit is determined to be normal, and a corresponding correction strategy is matched according to the charging status. According to the preset fixed voltage value By combining the temperature-compensated line loss voltage drop value, the output voltage is corrected to obtain the corrected output voltage. for: ; According to the preset charging curve target value By combining the temperature-compensated line loss voltage drop value, a corrected output voltage is generated. for: ; If not, it is determined that the charging circuit is abnormal, triggering a line loss abnormality alarm and reducing power output.

[0039] In this embodiment, the charger controller parses the actual total battery pack voltage VBMS from the transparent data packet uploaded by the BMS and records the corresponding acquisition timestamp tBMS.

[0040] The charger controller acquires the output voltage VOUT in real time through its internal voltage sampling circuit and records the sampling timestamp tOUT.

[0041] The controller compares tBMS with tOUT. If the difference is within the preset synchronization tolerance range, it is determined that the data is from the same time and proceeds directly to the next calculation step; if the difference exceeds the tolerance, the controller uses interpolation to extrapolate VOUT to the equivalent value at the time of tBMS, ensuring that the calculation benchmark is consistent.

[0042] The controller substitutes the synchronized VOUT and VBMS into the formula to calculate the current line loss voltage drop Vloss. The calculation formula is: Vloss = VOUT − VBMS The controller synchronously acquires the current charging current I and calculates the current total line resistance Rtotal based on Vloss, using the formula Rtotal = Vloss / I. The controller compares the current Rtotal with the reference line resistance Rbase obtained from the initial calibration to obtain the dynamic offset ΔR of the current line resistance, which is used to compensate for line resistance drift caused by factors such as temperature changes.

[0043] The controller compares the calculated Vloss with the preset line loss voltage drop safety threshold, and synchronously compares the ratio of Rtotal to Rbase with the preset resistance drift threshold: If Vloss is within a reasonable range and the Rtotal / Rbase ratio does not exceed the threshold, it is determined that the line loss calculation is valid, and the process proceeds to the voltage correction flow; If Vloss exceeds the safety threshold or the Rtotal / Rbase ratio exceeds the drift threshold, it is determined that the line is abnormal, and a line loss abnormality alarm is triggered.

[0044] The controller identifies the current stage according to the current charging state, and the identification rules are as follows: Pre-charging stage: the voltage is lower than the pre-charging threshold, and charging is performed at a small current; Constant current / fast charging stage: the voltage is in the fast charging range, and charging is performed at a constant large current; Constant voltage / saturation charging stage: the voltage is close to the full charge voltage, and the current gradually decreases.

[0045] The controller determines the battery end target voltage Vtarget according to the current charging stage: Pre-charging / constant current / fast charging stage: Vtarget is taken from the target value of the preset charging curve at the current moment; Constant voltage / saturation charging stage: Vtarget is set to the preset full charge voltage value (e.g., 4.2V per cell × number of series connections), and temperature compensation correction is performed in combination with the temperature coefficient.

[0046] The controller selects the corresponding correction formula according to the current charging stage: Pre-charging / constant current stage: VOUT_new=Vtarget+Vloss; Constant voltage / saturation charging stage: VOUT_new=Vtarget+Vloss; The controller calculates the additional voltage drop correction amount Vdrift caused by line resistance drift based on ΔR, which is the difference between the current total line resistance Rtotal and the initial reference resistance Rbase, combined with the current current I: Vdrift=ΔR×I Vdrift is superimposed on the basic correction voltage to obtain the compensated output correction voltage: VOUT_corr=VOUT_new+Vdrift; The controller compares VOUT_corr with the safety output voltage upper limit Vmax and lower limit Vmin of the charger: If VOUT_corr>Vmax, the correction voltage is limited to Vmax, and a limiting alarm is triggered; If VOUT_corr<Vmin, the correction voltage is limited to Vmin; If it is within a safe range, use the calculated value directly.

[0047] At the same time, the controller limits the rate of change of the corrected output voltage, so that the change of the output corrected voltage in adjacent control cycles does not exceed the preset upper limit of the voltage change rate, thus preventing sudden changes in output voltage from impacting the battery.

[0048] The controller writes the final output correction voltage VOUT_corr into the control register of the charger power module, driving the power module to adjust the output voltage.

[0049] In the next control cycle, the controller rereads the actual voltage VOUT_new_actual at the charger output terminal and receives a new BMS data packet to obtain the current actual voltage VBMS_new at the battery terminal. It then performs line loss calculation and correction again, forming a continuous closed-loop control. When Vloss increases, the output voltage automatically rises; When Vloss decreases, the output voltage automatically drops back down.

[0050] The controller repeats the above steps at fixed intervals (e.g., 100ms) to continuously track changes in Vloss and update the output correction voltage, ensuring that the actual battery voltage always accurately follows the target charging curve. Simultaneously, by incorporating a weighted average of historical correction values, the controller avoids drastic changes in the correction voltage caused by instantaneous fluctuations, ensuring a stable and smooth charger output.

[0051] Reference Figure 4 A charging voltage line loss compensation control system based on BMS closed-loop feedback, applied to a charging voltage line loss compensation control method, includes: The data acquisition and transmission module is used by the battery-side BMS to acquire the total voltage of the battery pack, generate and transmit transparent data packets to the charger controller. The receiving and parsing module is used by the charger controller to receive and parse the transparent data packets, extract the actual total voltage, and obtain the output voltage inside the charger. The line loss correction module is used to calculate the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generate the output correction voltage in conjunction with the line loss correction mechanism.

[0052] In this embodiment, in a high-frequency wireless charging system for lithium-ion forklifts in a large smart logistics park, the system is composed of a data acquisition and transmission module, a receiving and parsing module, and a line loss correction module. The data acquisition and transmission module includes a voltage detection unit (responsible for acquiring the total battery pack voltage at a 10kHz sampling rate), a temperature compensation unit (correcting temperature drift in the sampled values), a data encoding unit (packaging the corrected voltage and battery ID into a CAN transparent frame), and a CAN communication unit (transmitting data to the charger at a 1Mbps rate via the charging gun cable). The receiving and parsing module includes a link decoding unit (stripping the CAN message frame header and checksum), a data extraction unit (restoring the actual total voltage), a charger internal sampling unit (reading the terminal voltage measured by the Hall sensor at the output end), and a status synchronization unit (aligning the timestamps of the two voltages to ensure data is compared at the same time). The line loss correction module includes a voltage drop calculation unit (calculating the voltage drop at the output end...). The system consists of a voltage compensation unit (ΔV = 0.45V at this moment), a range determination unit (which compares ΔV with three preset thresholds: ΔV ≤ 0.15V indicates good line contact, 0.15V < ΔV ≤ 0.75V indicates normal line loss, and ΔV > 0.75V indicates line abnormality), a compensation generation unit (which generates a voltage compensation value of 0.45V for the normal line loss range at a ratio of ΔV × 1.0), and an output update unit (which adjusts the charger output voltage to 24.2V + 0.45V = 24.65V). Ultimately, the compensated output voltage is transmitted to the battery via cable, and the actual voltage recovers to the target value of 24.2V. The entire compensation process cycles every 100ms, dynamically adapting to line loss fluctuations caused by changes in charging current (e.g., 80A → 15A), effectively ensuring the charging accuracy and long-term cycle life of the forklift battery pack during rapid charging.

[0053] Fourthly, a storage medium storing at least one instruction, at least one program, code set, or instruction set, wherein the at least one instruction, at least one program, code set, or instruction set is loaded and executed by a processor to implement the charging voltage line loss compensation control method based on BMS closed-loop feedback as described above.

[0054] The embodiments described in this specific implementation are preferred embodiments of this application and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A charging voltage line loss compensation control method based on BMS closed-loop feedback, characterized in that, include: The battery-side BMS collects the total voltage of the battery pack, generates and transmits transparent data packets to the charger controller; The charger controller receives and parses the transparent data packet, extracts the actual total voltage, and obtains the output voltage inside the charger. Based on the actual total voltage and the output voltage, the real-time line loss voltage drop is calculated, and the output correction voltage is generated by combining the line loss correction mechanism.

2. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 1, characterized in that, The battery-side BMS collects the total voltage of the battery pack, generates and transmits transparent data packets to the charger controller, including: The battery-side BMS samples the voltage between the positive and negative terminals of the battery pack through a voltage sampling circuit to obtain the total voltage of the battery pack. The battery-side BMS filters and denoises the total voltage of the battery pack according to the sampling period to obtain the standard total voltage. If the standard total voltage is within the preset effective voltage range, the current standard total voltage is determined to be the actual total voltage, and a transparent data packet is generated in conjunction with the preset communication protocol. The communication interface of the battery-side BMS transmits transparent data packets to the charger controller.

3. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 1, characterized in that, The charger controller receives and parses the transparent data packet, extracts the actual total voltage, and obtains the output voltage inside the charger, including: The charger controller receives transparent data packets through the communication interface and temporarily stores them in the buffer. In the buffer, frame header verification, frame trailer verification, and checksum verification are performed on the transparent data packets according to the communication protocol. If all verifications are successful, the transparent data packet is parsed according to the data packet format to locate and extract the payload; The charger controller converts the payload according to the byte order and data type to obtain the actual total voltage; The charger controller detects the charger output terminal through a voltage sampling circuit to obtain the analog voltage signal at the output terminal; The charger controller filters and transforms the analog voltage signal at the output terminal to obtain the output voltage.

4. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 1, characterized in that, The process of calculating real-time line loss voltage drop based on the actual total voltage and output voltage, and generating an output correction voltage using a line loss correction mechanism, includes: Match the sampling timestamps of the actual total voltage and the output voltage, and calculate the timestamp difference. If the timestamp difference is greater than or equal to the preset synchronization tolerance threshold, it is determined to be voltage data at different times, and the sampling timestamp of the output voltage is interpolated and extrapolated to the sampling timestamp of the actual total voltage. If the timestamp difference is less than the synchronization tolerance threshold, it is determined to be voltage data at the same time, and the initial line resistance reference value is calculated based on the preset calibration current. For the actual total voltage With output voltage Perform the difference calculation to obtain the current line loss voltage drop value. ; Based on the total resistance of the charging circuit and the initial line resistance reference value, calculate the dynamic offset of the line resistance and the line resistance ratio. Based on the dynamic offset of the line resistance and the thermal drift coefficient of the line resistance, the current line loss voltage drop value is corrected to obtain the temperature-compensated line loss voltage drop value: , in, V loss_comp To compensate for line loss voltage drop, R ref This is the initial reference value for the line resistance. ΔR This represents the dynamic offset of the line resistance. α This is the thermal drift coefficient of the line resistance. ΔT This represents the change in temperature.

5. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 4, characterized in that, The process of calculating the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generating the output correction voltage using the line loss correction mechanism, also includes: If the temperature compensation line loss voltage drop is less than the preset line loss voltage drop safety threshold and the line resistance ratio is less than the preset resistance drift threshold, the charging circuit is determined to be normal, and a corresponding correction strategy is matched according to the charging status. If the current charging state is the pre-charge / constant current stage, the output voltage is corrected according to the preset fixed voltage value and the temperature compensation line loss voltage drop value to obtain the corrected output voltage. If the current charging state is fast charging / saturated charging stage, a corrected output voltage is generated based on the preset charging curve target value and the temperature compensation line loss voltage drop value. If not, it is determined that the charging circuit is abnormal, triggering a line loss abnormality alarm and reducing power output.

6. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 5, characterized in that, The method is based on a preset fixed voltage value. By combining the temperature-compensated line loss voltage drop value, the output voltage is corrected to obtain the corrected output voltage. for: .

7. The charging voltage line loss compensation control method based on BMS closed-loop feedback according to claim 5, characterized in that: The target value based on the preset charging curve By combining the temperature-compensated line loss voltage drop value, a corrected output voltage is generated. for: 。 8. A charging voltage line loss compensation control system based on BMS closed-loop feedback, used to implement the charging voltage line loss compensation control method based on BMS closed-loop feedback as described in any one of claims 1-7, characterized in that, include: The data acquisition and transmission module is used by the battery-side BMS to acquire the total voltage of the battery pack, generate and transmit transparent data packets to the charger controller. The receiving and parsing module is used by the charger controller to receive and parse the transparent data packets, extract the actual total voltage, and obtain the output voltage inside the charger. The line loss correction module is used to calculate the real-time line loss voltage drop based on the actual total voltage and the output voltage, and generate the output correction voltage in conjunction with the line loss correction mechanism.

9. A storage medium storing at least one instruction, at least one program, a code set, or an instruction set, wherein the at least one instruction, the at least one program, the code set, or the instruction set is loaded and executed by a processor to implement the charging voltage line loss compensation control method based on BMS closed-loop feedback as described in any one of claims 1 to 7.

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