Storage battery charging control method and system and new energy engineering machinery

Abstract

The invention discloses a storage battery charging control method and system and a new energy engineering machine, and relates to the vehicle control technology. The method comprises the following steps: when a DCDC controller stops receiving a VCU enable signal, entering a sampling evaluation stage, detecting the current and voltage of a low-voltage loop, and calculating the SOH of the storage battery based on a temperature self-adaptive SOC-voltage characteristic curve; if the SOH is lower than the threshold value, entering a primary energy complementing stage, and enabling the DCDC to work and control the power complementing duration based on the detection data; entering a precise checking stage after energy supplementation, detecting the voltage to obtain a checking SOC, and supplementing energy again if the SOC does not reach the standard. The system comprises a VCU, a BMS, a PDU, a DCDC controller and other components. According to the invention, precise self-adaptive power compensation is realized, and particularly, the evaluation precision is improved through temperature compensation, and the service life of the storage battery is prolonged.

Description

Technical Field

[0001] This invention relates to the field of new energy vehicle control technology, and in particular to a battery charging control method, system, and new energy engineering machinery. Background Technology

[0002] In new energy construction machinery vehicles (such as new energy heavy trucks), reliable low-voltage battery charging is crucial for the normal operation of the entire vehicle. Traditional charging strategies often employ simple timed charging methods, charging at fixed time intervals or for fixed durations. This method has significant drawbacks: because the output voltage of the DC-DC converter is the highest point in the vehicle's low-voltage circuit during operation, it is impossible to directly detect the actual battery voltage, making it difficult to accurately judge the charging progress. This can easily lead to two adverse situations: first, insufficient charging, leaving the battery in a chronically undercharged state, affecting its lifespan; second, overcharging, where the DC-DC converter continues to operate inefficiently even when the battery is fully charged, resulting in energy waste.

[0003] While some intelligent charging solutions exist in the current technology, most fail to fully consider changes in the battery's state of health (SOH), particularly the impact of temperature on the SOC-voltage characteristic curve, leading to inaccurate SOH assessments. Furthermore, traditional solutions cannot accurately assess the actual amount of electricity required for charging, especially in effectively addressing dynamic changes in the current consumed by the vehicle's low-voltage controller.

[0004] In summary, the existing technology has the following problems:

[0005] (1) The problem that the charging process cannot accurately reflect the true state of the battery;

[0006] (2) Traditional SOH assessment does not consider the effect of temperature, which leads to inaccurate assessment;

[0007] (3) The problem that the charging strategy cannot adapt to batteries in different health states;

[0008] (4) The problem of not being able to dynamically adjust the power replenishment cycle during the power replenishment process.

[0009] Therefore, there is an urgent need in this field for an intelligent power replenishment method that can achieve precise power replenishment, adapt to changes in battery status and temperature, dynamically adjust the power replenishment cycle, and has a fault-prevention cycle mechanism. Summary of the Invention

[0010] The purpose of this invention is to overcome the shortcomings of the prior art and provide a battery charging control method, system and new energy engineering machinery that can achieve precise charging, adapt to changes in battery status and temperature, dynamically adjust charging parameters and have a fault-prevention cycle mechanism.

[0011] To achieve the above objectives, the present invention is implemented using the following technical solution:

[0012] In a first aspect, the present invention provides an integral DC-DC intelligent power replenishment method for new energy engineering machinery, wherein the method uses a DC-DC controller as the execution subject and includes the following steps:

[0013] Step A: When the DC-DC enable signal sent by the vehicle controller VCU is stopped, the DC-DC is controlled to stop working, and the real-time voltage of the battery and the total current of the vehicle's low-voltage circuit are detected and recorded in real time when the DC-DC is not working.

[0014] Step B: Obtain the ambient temperature, and query the SOC-voltage characteristic curve based on the real-time voltage and ambient temperature to obtain the real-time SOC when the DC-DC converter is not working;

[0015] Step C: If the real-time SOC is lower than the preset startup charging threshold, then proceed to step D;

[0016] Step D: Calculate and obtain the battery's state of health (SOH) based on the recorded real-time battery voltage and total low-voltage circuit current of the vehicle when the DC-DC converter is not working.

[0017] Step E: Request the VCU to perform high-voltage power distribution, so that the DC-DC converter starts working and charges the low-voltage battery. Obtain and determine whether the charging completion conditions are met based on the battery voltage, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter at the moment before it starts working, and the battery's state of health (SOH). If the conditions are met, proceed to step F; otherwise, continue to step E.

[0018] Step F: The DC-DC controller requests the VCU to stop high-voltage power distribution, causing the DC-DC to stop working; the battery voltage is detected again, and the SOC is verified based on the SOC-voltage characteristic curve;

[0019] Step G: If the verified SOC does not reach the preset charging completion threshold, then repeat steps D-F.

[0020] Furthermore, in step D, based on the recorded real-time battery voltage when the DC-DC converter is not operating and the total current of the vehicle's low-voltage circuit, the battery's state of health (SOH) is calculated, including:

[0021] Obtain the total low-voltage circuit current of the vehicle and the real-time battery voltage V1 at each moment. a ;

[0022] Record the initial and final voltages of the battery within a preset unit time t after the DC-DC converter stops working;

[0023] Based on the ambient temperature, the SOC-voltage characteristic curve corresponding to the ambient temperature is selected from the pre-stored SOC-voltage characteristic curves at multiple temperatures;

[0024] Based on the initial voltage and the final voltage, the SOC-voltage characteristic curve of the corresponding ambient temperature is queried to obtain the initial SOC and the final SOC, and the change in SOC ΔSOC = initial SOC - final SOC is calculated;

[0025] The total current of the vehicle's low-voltage circuit and the recorded real-time voltage of the battery are superimposed over a preset unit time t to estimate the energy consumption ΔW.

[0026]

[0027] Where Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples taken per unit time t; I1 a V1 is the total low-voltage circuit current of the entire vehicle at time a. a Let I1 be the real-time voltage of the battery at time a. a-1 V1 represents the total low-voltage circuit current of the entire vehicle at time a-1. a-1 Let be the real-time voltage of the battery at time a-1;

[0028] The SOH is calculated using the following formula:

[0029] SOH = ΔW / (ΔSOC × total battery capacity) × 100%.

[0030] Furthermore, the SOC-voltage characteristic curve is obtained from the battery product manual and includes the correspondence between SOC and voltage under different temperature conditions.

[0031] Furthermore, the preset unit time t is 10 minutes.

[0032] Furthermore, in step E, based on the battery voltage just before the DC-DC converter operates, the total current of the vehicle's low-voltage circuit, and the output voltage and current of the DC-DC converter during operation, combined with the battery's state of health (SOH), it is determined whether the conditions for completing the charging process are met, including:

[0033] Obtain the output voltage V2 at various times during the operation of the DC-DC converter. a and output current I2 a ;

[0034] Obtain the battery voltage V1 just before the DCDC starts operating based on the recorded real-time battery voltage. N ;

[0035] The total current I1 of the vehicle's low-voltage circuit at the moment before the DCDC starts operating is obtained based on the recorded total current of the vehicle's low-voltage circuit. N ;

[0036] Based on the battery voltage V1 at the moment before the operation N Query the SOC-voltage characteristic curve for the corresponding ambient temperature to obtain the real-time SOC;

[0037] The theoretically required SOC difference ΔSOC = 100% - real-time SOC;

[0038] Calculate the required energy ΔW 补 =ΔSOC × Total battery capacity × SOH;

[0039] Calculate the actual energy replenishment W using the following formula. 补 :

[0040]

[0041] Where Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples. V1 N and I1 N These are the battery output voltage and output current just moments before the DC-DC converter starts operating; I2 a V2 is the output current of the DC-DC converter at time a during operation. a Let I2 be the output voltage of the DC-DC converter at time a. a-1 V2 is the output current of the DC-DC converter at time a-1. a-1 The output voltage of the DC-DC converter at time a-1 is the output voltage when it is operating.

[0042] If and only if the actual energy replenishment W 补 Greater than or equal to the required energy ΔW 补 When the conditions for completing the power replenishment are met, it is determined that the conditions for completing the power replenishment are met.

[0043] Furthermore, step E also includes a dual-mode power selection step:

[0044] When the SOH is lower than the preset SOH threshold, the intelligent charging mode is activated. Based on the battery voltage just before the DC-DC converter starts working, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter when it is working, and the battery's health status SOH, it is determined whether the charging completion conditions are met.

[0045] When the SOH is higher than or equal to the preset SOH threshold, a quantitative charging mode is adopted, and charging is performed according to the preset fixed charging energy required.

[0046] Furthermore, in step 3, the preset charging completion threshold is 95%, and the charging start threshold is 80%.

[0047] Furthermore, if the verified SOC still fails to reach the preset power replenishment completion threshold after three consecutive re-executions of steps D-F, the power replenishment process is interrupted.

[0048] Furthermore, if the real-time SOC is greater than or equal to the preset start-up charging threshold, the battery is determined to be sufficiently charged, the charging process ends, and the system enters hibernation mode.

[0049] In a second aspect, the present invention provides a battery charging control system, comprising:

[0050] The vehicle control unit (VCU) is used to control the vehicle's high-voltage power supply and the transmission of DC-DC enable signals.

[0051] A battery management system (BMS) is used to manage the status of high-voltage batteries.

[0052] High-voltage distribution unit (PDU) is used for high-voltage power distribution management;

[0053] Low-voltage batteries are used as a source of supplementary power.

[0054] Temperature sensor, used to detect ambient temperature;

[0055] The DC-DC converter is connected to the high-voltage distribution cabinet PDU and the low-voltage battery respectively, and is used to charge the low-voltage battery.

[0056] The DC-DC controller is communicatively connected to the VCU, the BMS, the PDU, and the temperature sensor. The DC-DC controller is configured to automatically execute the integral DC-DC intelligent power replenishment method described in the first aspect after stopping and receiving the DC-DC enable signal from the VCU, thereby controlling the DC-DC to perform power replenishment.

[0057] Thirdly, the present invention provides a new energy engineering machinery, including a battery charging control system as described in the second aspect.

[0058] Compared with the prior art, the beneficial effects achieved by the present invention are as follows:

[0059] 1. Real-time Precise Status Monitoring: By employing a technology that detects and records the battery voltage in real time when the DC-DC converter is not operating, combined with an ambient temperature-compensated SOC query mechanism, precise real-time monitoring of the battery status is achieved. The control strategy involved in this invention enables precise recharging, improves control accuracy, reduces ineffective power consumption during recharging compared to existing recharging methods, enhances the accuracy of recharging initiation timing, and avoids unnecessary recharging operations.

[0060] 2. The control strategy involved in this invention is divided into three stages, which can adapt to batteries with different health levels. Compared with existing charging strategies, it can make adaptive charging strategies for batteries with different health levels. Due to the use of integral power calculation in the intelligent charging mode, combined with the SOH calculation method based on the integral of total current I1 and voltage change, by recording the voltage drop process and calculating the SOC change, and combining the current time integral to estimate energy consumption, the accurate assessment of battery health status is achieved.

[0061] 3. By adopting the technical feature of incorporating ambient temperature into the selection of the SOC-voltage characteristic curve, the problem of SOC evaluation deviation caused by temperature changes in traditional methods is solved, the accuracy of SOC evaluation remains stable, and the evaluation error under extreme temperature conditions is significantly reduced.

[0062] 4. This invention evaluates the varying power consumption of the vehicle's low-voltage controller, calculates the actual energy required for replenishment, and adaptively adjusts the replenishment current based on the vehicle's actual power consumption, improving accuracy. Furthermore, this invention can precisely verify and compensate for any additional controller power consumption during the replenishment process. By employing real-time monitoring of the low-voltage circuit current and voltage and dynamically calculating the required replenishment power, it effectively reduces ineffective power consumption. Actual testing shows that compared to traditional timed replenishment, this invention reduces ineffective charging time and improves overall vehicle energy efficiency.

[0063] 5. To prevent battery damage from causing endless charging, this invention incorporates an anti-cycle fault warning strategy. Compared to existing charging methods, this avoids battery damage leading to continuous charging and excessively low battery power. It employs a cyclic mechanism combined with a three-failure interruption feature, ensuring effective charging while preventing dead-cycle charging due to battery failure. System reliability is improved compared to traditional solutions, effectively avoiding the risks of battery over-discharge and DC-DC controller overload.

[0064] 6. System integration advantages: Due to the technical features of using a DC-DC controller as the main actuator and having built-in SOC-voltage characteristic curve data, the hardware resources are optimized and there is no need to add an additional dedicated power supply controller, which reduces system cost and complexity.

[0065] 7. Due to the adoption of a dual-mode charging mechanism based on SOH threshold judgment, this invention can intelligently select the optimal charging strategy according to the actual health status of the battery. When SOH is lower than the preset threshold, the intelligent charging mode is activated, and the charging duration is dynamically controlled based on the total current I1 and the current voltage V1 to achieve precise maintenance of the aging battery; when SOH is higher than or equal to the preset threshold, the conventional fixed-duration charging mode is adopted to improve charging efficiency.

[0066] 8. The control strategy involved in this invention has high versatility and can be used in vehicles with low-voltage batteries of different capacities. Attached Figure Description

[0067] Figure 1 This is a flowchart of the intelligent power replenishment method according to an embodiment of the present invention;

[0068] Figure 2 This is a schematic diagram of the intelligent power replenishment system for new energy engineering machinery according to an embodiment of the present invention. Detailed Implementation

[0069] The present invention will be further described below with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and should not be used to limit the scope of protection of the present invention.

[0070] Example 1:

[0071] This embodiment provides an integral DC-DC intelligent charging method for new energy construction machinery. The method uses a DC-DC controller as the main actuator and works in conjunction with the vehicle control unit (VCU), battery management system (BMS), high-voltage distribution unit (PDU), low-voltage battery, and temperature sensor. The method includes the following steps:

[0072] like Figure 1 As shown in the figure, this embodiment provides a battery charging control method, and the specific implementation process is as follows:

[0073] Step A: When the DC-DC enable signal sent by the vehicle controller VCU is stopped, the DC-DC is controlled to stop working, and the real-time voltage of the battery and the total current of the vehicle's low-voltage circuit are detected and recorded in real time when the DC-DC is not working.

[0074] Step B: Obtain the ambient temperature, and query the SOC-voltage characteristic curve based on the real-time voltage and ambient temperature to obtain the real-time SOC when the DC-DC converter is not working;

[0075] Step C: If the real-time SOC is lower than the preset startup charging threshold, then proceed to step D;

[0076] Step D: Based on the recorded real-time battery voltage and total low-voltage circuit current of the vehicle when the DC-DC converter is not working, calculate and obtain the battery's State of Health (SOH).

[0077] Obtain the total low-voltage circuit current of the vehicle and the real-time battery voltage V1 at each moment. a ;

[0078] Record the initial and final voltages of the battery within a preset unit time t after the DC-DC converter stops working;

[0079] Based on the ambient temperature, the SOC-voltage characteristic curve corresponding to the ambient temperature is selected from the pre-stored SOC-voltage characteristic curves at multiple temperatures;

[0080] Based on the initial voltage and the final voltage, the SOC-voltage characteristic curve of the corresponding ambient temperature is queried to obtain the initial SOC and the final SOC, and the change in SOC ΔSOC = initial SOC - final SOC is calculated;

[0081] The total current of the vehicle's low-voltage circuit and the recorded real-time voltage of the battery are superimposed over a preset unit time t to estimate the energy consumption ΔW.

[0082]

[0083] Where Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples taken per unit time t; I1 a V1 is the total low-voltage circuit current of the entire vehicle at time a. a Let I1 be the real-time voltage of the battery at time a. a-1 V1 represents the total low-voltage circuit current of the entire vehicle at time a-1. a-1 Let be the real-time voltage of the battery at time a-1;

[0084] The SOH is calculated using the following formula:

[0085] SOH = ΔW / (ΔSOC × total battery capacity) × 100%.

[0086] The SOC-voltage characteristic curve is obtained from the battery product manual and includes the correspondence between SOC and voltage under different temperature conditions.

[0087] If the real-time SOC is greater than or equal to the preset start-up charging threshold, the battery is deemed to have sufficient power, the current charging process ends, and the system enters hibernation mode.

[0088] Step E: Request the VCU to perform high-voltage power distribution, so that the DC-DC converter starts working and charges the low-voltage battery. Obtain and determine whether the charging completion conditions are met based on the battery voltage, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter at the moment before it starts working, and the battery's state of health (SOH). If the conditions are met, proceed to step F; otherwise, continue to step E.

[0089] Methods for determining whether the conditions for completing the power replenishment are met include:

[0090] Obtain the output voltage V2 at various times during the operation of the DC-DC converter. a and output current I2 a ;

[0091] Obtain the battery voltage V1 just before the DCDC starts operating based on the recorded real-time battery voltage. N ;

[0092] The total current I1 of the vehicle's low-voltage circuit at the moment before the DCDC starts operating is obtained based on the recorded total current of the vehicle's low-voltage circuit. N ;

[0093] Based on the battery voltage V1 at the moment before the operation N Query the SOC-voltage characteristic curve for the corresponding ambient temperature to obtain the real-time SOC;

[0094] The theoretically required SOC difference ΔSOC = 100% - real-time SOC;

[0095] Calculate the required energy ΔW 补 =ΔSOC × Total battery capacity × SOH;

[0096] Calculate the actual energy replenishment W using the following formula. 补 :

[0097]

[0098] Where Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples. V1 N and I1 N These are the battery output voltage and output current just moments before the DC-DC converter starts operating; I2 a V2 is the output current of the DC-DC converter at time a during operation. a Let I2 be the output voltage of the DC-DC converter at time a. a-1 V2 is the output current of the DC-DC converter at time a-1. a-1 The output voltage of the DC-DC converter at time a-1 is the output voltage when it is operating.

[0099] If and only if the actual energy replenishment W 补 Greater than or equal to the required energy ΔW 补 When the conditions for completing the power replenishment are met, it is determined that the conditions for completing the power replenishment are met.

[0100] Step E also includes a dual-mode power selection step:

[0101] When the SOH is lower than the preset SOH threshold, the intelligent charging mode is activated. Based on the battery voltage just before the DC-DC converter starts working, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter when it is working, and the battery's health status SOH, it is determined whether the charging completion conditions are met.

[0102] When the SOH is higher than or equal to the preset SOH threshold, a quantitative charging mode is adopted, and charging is performed according to the preset fixed charging energy required.

[0103] Preferably, if the verified SOC still fails to reach the preset power replenishment completion threshold after three consecutive re-executions of steps D-F, the power replenishment process is interrupted.

[0104] Step F: The DC-DC controller requests the VCU to stop high-voltage power distribution, causing the DC-DC to stop working; the battery voltage is detected again, and the SOC is verified based on the SOC-voltage characteristic curve;

[0105] Step G: If the verified SOC does not reach the preset charging completion threshold, then repeat steps D-F.

[0106] The intelligent power replenishment mode in this embodiment is divided into three stages: sampling and evaluation stage, primary power replenishment stage, and precise verification stage.

[0107] The sampling phase includes the DC-DC controller detecting the total current of the vehicle's low-voltage circuit and the current voltage of the battery;

[0108] The first energy replenishment phase includes:

[0109] When entering intelligent charging mode, the DC-DC controller first requests the VCU. The VCU controls the BMS and PDU to achieve high-voltage power distribution to the DC-DC. The DC-DC starts working to charge the low-voltage battery and controls the charging duration based on the detection phase data.

[0110] The precise verification stage includes: Since the current used by the low-voltage controllers of the vehicle changes during the charging process, the current battery voltage needs to be re-verified after one charging cycle. Based on the battery voltage, the SOC after one charging cycle is obtained by looking up the table. If the SOC is less than 95%, the charging cycle is repeated. The charging algorithm is the same as the first charging cycle.

[0111] To avoid repeated charging cycles caused by battery failure, if the battery still falls short of the preset value after three consecutive accurate calibrations, the current intelligent charging process will be interrupted.

[0112] Example 2:

[0113] This embodiment details the specific implementation process of the integral DC-DC intelligent power replenishment method. For example... Figure 1 As shown, the method uses a DC-DC controller as the execution entity and includes the following specific steps:

[0114] Before the system starts, the following initialization configurations must be completed:

[0115] 1. Establishment of SOC-Voltage Characteristic Curve Library: Based on the battery product manual, the SOC-voltage correspondence under different temperature conditions is stored in the non-volatile memory of the DCDC controller, covering a temperature range of -30℃ to 60℃, with a temperature interval of 5℃. Each curve contains at least 100 data points to ensure the accuracy of interpolation calculations.

[0116] 2. System parameter presets:

[0117] Start-up charging threshold: Set to 80% SOC (adjustable within the range of 70%-95%).

[0118] Recharge completion threshold: Set to 95% SOC (can be adjusted within the range of 90%-98%).

[0119] SOH judgment threshold: set to 80% (can be adjusted within the range of 70%-90%);

[0120] Sampling period Δt: set to 100ms (corresponding to a 10Hz sampling frequency);

[0121] Preset unit time t: Set to 10 minutes (can be adjusted within 5-15 minutes);

[0122] Step A: Data Acquisition and DC-DC Working Status Monitoring:

[0123] When the DC-DC controller detects via the CAN bus that the VCU has stopped sending the DC-DC enable signal:

[0124] Immediately send a stop command to the DC-DC converter to ensure that the DC-DC converter completely stops outputting;

[0125] Start the high-precision data acquisition system:

[0126] The voltage across the battery terminals is acquired at a frequency of 10Hz using a 16-bit ADC, with a measurement range of 0-20V and an accuracy of ±0.1%.

[0127] The total current of the vehicle's low-voltage circuit is collected synchronously using a Hall current sensor with a range of ±100A and an accuracy of ±1%.

[0128] Establish a circular data buffer to store voltage and current data and corresponding timestamps for the most recent 15 minutes;

[0129] The collected data is digitally filtered, and a median filtering combined with a moving average algorithm is used to effectively suppress impulse interference and random noise.

[0130] Step B: Precise calculation of SOC with ambient temperature compensation:

[0131] The ambient temperature is acquired in real time using a temperature sensor with a sampling frequency of 1Hz and an accuracy of ±0.5℃.

[0132] Temperature data is transmitted to the DC-DC controller via a single-bus protocol;

[0133] SOC calculation process:

[0134] 1. Calculate the average of the 10 most recent temperature samples to obtain the current ambient temperature.

[0135] 2. Select the closest temperature curve from the characteristic curve library using the nearest neighbor method.

[0136] 3. Perform linear interpolation calculations on the selected characteristic curve for the current voltage value.

[0137] Step C: Intelligent decision-making for power replenishment and startup:

[0138] Compare the calculated real-time SOC with the startup power-up threshold:

[0139] If the real-time SOC is less than 80%, generate a power-on start flag and proceed to step D;

[0140] If the real-time SOC is ≥80%, record the monitoring data and the system enters low-power standby mode;

[0141] The decision-making process takes into account historical data trends. If the rate of decline of SOC exceeds the set value, the power replenishment will be initiated even if the current SOC is higher than the threshold.

[0142] Step D: Precise assessment of battery health status:

[0143] During the DCDC shutdown period, the system performs a complete SOH assessment process:

[0144] 1. Data preprocessing:

[0145] Extract the voltage and current time series from the buffer for the most recent 10 minutes;

[0146] Remove and interpolate abnormal data;

[0147] Calculate the rate of voltage change and identify the stable voltage drop range.

[0148] 2. Calculation of SOC change:

[0149] Take the average voltage of the first 30 seconds as the initial voltage;

[0150] Take the average voltage over the last 30 seconds as the final voltage;

[0151] Select the corresponding SOC-voltage characteristic curve based on the current ambient temperature;

[0152] The initial SOC and the final SOC are obtained through interpolation calculation;

[0153] ΔSOC = Initial SOC - Final SOC.

[0154] 3. Precise energy consumption calculation:

[0155] The energy consumption ΔW is calculated using the trapezoidal integral method:

[0156]

[0157] Where a ranges from 1 to N, and N = 6000 (corresponding to 10 minutes, with a sampling period of 100ms).

[0158] 4. SOH Calculation:

[0159] SOH = ΔW / (ΔSOC × total battery capacity) × 100%.

[0160] The rated capacity of the battery varies depending on the specific vehicle model configuration, with a typical value of 100Ah.

[0161] Step E: Intelligent power replenishment execution and real-time monitoring:

[0162] The DC-DC controller sends a power-up request to the VCU via the CAN bus, executing the following process:

[0163] 1. High-voltage power-on sequence:

[0164] After receiving the power replenishment request, the VCU first checks the status of the high-voltage battery through the BMS;

[0165] Send a pre-charge command to control the PDU to execute the pre-charge process;

[0166] After pre-charging is complete, the main contactor is engaged to establish high-voltage power supply.

[0167] 2. Dual-mode charging selection:

[0168] If SOH < 80%, activate the intelligent power replenishment mode.

[0169] If SOH ≥ 80%, activate the quantitative (or timed) power replenishment mode and replenish power according to a fixed amount.

[0170] 3. Implementation of intelligent power replenishment mode:

[0171] The DC-DC converter is activated, and the controller is monitoring at a frequency of 10Hz.

[0172] Output voltage V2 a (DC-CDC output terminal);

[0173] Output current I2 a (DC-CDC output terminal);

[0174] Judgment of the completion condition of supplementary charging:

[0175] a. Obtain the battery voltage V1 at the moment before the DCDC works N and the total current I1 N ;

[0176] b. Query the SOC-voltage curve to obtain the real-time SOC

[0177] c. Calculate the required supplementary energy: ΔW_supplementary = (100% - real-time SOC) × battery rated capacity × SOH

[0178] d. Calculate the actual supplementary charging in real time:

[0179]

[0180] e. When W_supplementary ≥ ΔW_supplementary, it is determined that the supplementary charging completion condition is met; otherwise, continue to perform supplementary charging.

[0181] Step F: Ordered shutdown and preliminary verification

[0182] The DCDC controller requests the VCU to execute the high-voltage power-down sequence:

[0183] 1. First, stop the DCDC from working;

[0184] 2. Disconnect the PDU main contactor after a 100ms delay;

[0185] 3. Execute the discharge process to ensure high-voltage safety;

[0186] Wait for the voltage stabilization period (30 seconds) to fully recover the battery voltage;

[0187] Detect the battery voltage again and calculate the preliminary verified SOC.

[0188] Step G: Loop verification and safety protection

[0189] If the verified SOC ≥ 95%, the supplementary charging is successful, and record the data of this supplementary charging;

[0190] If the verified SOC < 95%, re-execute steps D - F for supplementary charging /

[0191] Safety protection mechanism:

[0192] If the verified SOC still does not meet the standard after re-executing three times continuously, it is determined that the battery is faulty;

[0193] Immediately terminate the supplementary charging process and send a fault code through the CAN bus;

[0194] The fault code includes information such as the battery health status, cycle count, and final SOC value;

[0195] The system records detailed fault logs for subsequent diagnostic analysis.

[0196] The control strategy involved in this invention can achieve precise charging and improve control accuracy. Compared with existing charging methods, it can reduce ineffective power consumption during charging. The control strategy involved in this invention is divided into three stages, which can adapt to batteries with different health levels. Compared with existing charging strategies, it can implement an adaptive charging strategy for batteries with different health levels. The control strategy involved in this invention has high versatility and can be used in vehicles with low-voltage batteries of different capacities.

[0197] To prevent battery damage from causing endless charging, this invention implements an anti-cycle fault warning strategy. Compared to existing charging methods, this avoids battery damage leading to continuous charging and resulting in excessively low battery power. This invention also assesses the different power consumption of the vehicle's low-voltage controller, calculates the actual energy required for charging, and adaptively adjusts the charging current based on the vehicle's actual power consumption, improving accuracy. Furthermore, this invention can accurately verify and compensate for any additional controller power consumption during the charging process.

[0198] This invention establishes a novel intelligent battery maintenance system through an innovative integral DC-DC intelligent charging method. The system employs a real-time voltage detection combined with an ambient temperature-compensated SOC (State of Charge) precise query mechanism, achieving accurate perception of battery status and significantly improving the accuracy of charging timing judgment. By utilizing a library of characteristic curves under multiple temperature conditions and a current integral algorithm, a complete battery health assessment system is constructed, providing a reliable basis for formulating charging strategies. This real-time data-driven monitoring method effectively avoids the blindness of traditional charging strategies, ensuring the scientific rigor and reliability of battery status assessment.

[0199] Regarding the power replenishment control strategy, this invention innovatively employs a dual-mode intelligent selection mechanism, which can automatically select the optimal power replenishment scheme based on the actual health status of the battery. When the battery is in good condition, the system uses a high-efficiency power replenishment mode; when the battery shows signs of aging, it activates a precise maintenance mode, dynamically calculating the optimal power replenishment duration through real-time parameters. This adaptive power replenishment strategy ensures precise maintenance of aging batteries while optimizing the power replenishment efficiency of healthy batteries, achieving a perfect balance between precise maintenance and efficient operation.

[0200] The comprehensive benefits of this invention have been fully verified in practical applications. It not only significantly extends the lifespan of the battery but also optimizes operating costs through precise energy consumption control. The system demonstrates significant advantages in environmental adaptability, operational reliability, and economy, providing an innovative technical path for the development of power supply management technology for new energy vehicles and possessing broad application value.

[0201] Example 3:

[0202] The present invention also provides an intelligent power replenishment system for new energy engineering machinery, used to implement the above-mentioned integral DC-DC intelligent power replenishment method.

[0203] like Figure 2 As shown, the system includes: a vehicle control unit (VCU), a battery management system (BMS), a high-voltage distribution unit (PDU), a DC-DC controller, a low-voltage battery, and a temperature sensor.

[0204] The vehicle control unit (VCU) is used to control the vehicle's high-voltage power supply and the transmission of DC-DC enable signals.

[0205] A battery management system (BMS) is used to manage the status of high-voltage batteries.

[0206] High-voltage distribution unit (PDU) is used for high-voltage power distribution management;

[0207] The DC-DC controller serves as the main implementer of the intelligent power replenishment function;

[0208] Low-voltage batteries are used as a source of supplementary power.

[0209] Temperature sensor, used to detect outdoor temperature (ambient temperature);

[0210] The DC-DC controller, as the main body for executing the intelligent power replenishment function, has built-in SOC-voltage characteristic curve data and is used to execute the control method as described in Embodiment 1 or Embodiment 2. After stopping receiving the DC-DC enable signal from the VCU, it can automatically enter the intelligent power replenishment mode and execute the power replenishment process in three stages: sampling evaluation, primary power replenishment, and precise verification.

[0211] The system's reliability and safety are fully guaranteed through multiple protection mechanisms. An innovative cyclic verification mechanism ensures that the charging effect meets predetermined standards, while multiple fault protection designs effectively prevent system risks under abnormal conditions. Simultaneously, this invention optimizes the system structure through integrated design, improving system response speed and operational stability. In extended applications in the field of engineering machinery, the system demonstrates excellent adaptability to operating conditions, providing a complete technical solution for intelligent battery maintenance in new energy commercial vehicles.

[0212] Example 4:

[0213] This embodiment provides a new energy construction machinery, including a battery charging control system as described in Embodiment 3. New energy construction machinery mainly includes new energy heavy trucks, electric excavators, electric loaders, electric forklifts, electric concrete mixers, hydrogen fuel cell loaders, etc., and can be any construction machinery with DC-DC converters and battery functional components.

[0214] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0215] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0216] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0217] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0218] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A battery charging control method, characterized in that, Includes the following steps: Step A: When the DC-DC enable signal sent by the vehicle controller VCU is stopped, the DC-DC is controlled to stop working, and the real-time voltage of the battery and the total current of the vehicle's low-voltage circuit are detected and recorded in real time when the DC-DC is not working. Step B: Obtain the ambient temperature, and query the SOC-voltage characteristic curve based on the real-time voltage and ambient temperature to obtain the real-time SOC when the DC-DC converter is not working; Step C: If the real-time SOC is lower than the preset startup charging threshold, then proceed to step D; Step D: Calculate and obtain the battery's state of health (SOH) based on the recorded real-time battery voltage and total low-voltage circuit current of the vehicle when the DC-DC converter is not working. Step E: Request the VCU to perform high-voltage power distribution, so that the DC-DC converter starts working and charges the low-voltage battery. Obtain and determine whether the charging completion conditions are met based on the battery voltage, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter at the moment before it starts working, and the battery's state of health (SOH). If the conditions are met, proceed to step F; otherwise, continue to step E. Step F: The DC-DC controller requests the VCU to stop high-voltage power distribution, causing the DC-DC to stop working; the battery voltage is detected again, and the SOC is verified based on the SOC-voltage characteristic curve; Step G: If the verified SOC does not reach the preset charging completion threshold, then repeat steps D-F.

2. The battery charging control method according to claim 1, characterized in that, In step D, the battery's state of health (SOH) is calculated based on the recorded real-time battery voltage when the DC-DC converter is not operating and the total current of the vehicle's low-voltage circuit, including: Obtain the total low-voltage circuit current of the vehicle and the real-time battery voltage V1 at each moment. a ; Record the initial and final voltages of the battery within a preset unit time t after the DC-DC converter stops working; Based on the ambient temperature, the SOC-voltage characteristic curve corresponding to the ambient temperature is selected from the pre-stored SOC-voltage characteristic curves at multiple temperatures; Based on the initial voltage and the final voltage, the SOC-voltage characteristic curve of the corresponding ambient temperature is queried to obtain the initial SOC and the final SOC, and the change in SOC ΔSOC = initial SOC - final SOC is calculated; The total current of the vehicle's low-voltage circuit and the recorded real-time voltage of the battery are superimposed over a preset unit time t to estimate the energy consumption ΔW.

3. Among them, Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples taken per unit time t; I1 a V1 is the total low-voltage circuit current of the entire vehicle at time a. a Let I1 be the real-time voltage of the battery at time a. a-1 V1 represents the total low-voltage circuit current of the entire vehicle at time a-1. a-1 Let be the real-time voltage of the battery at time a-1; The SOH is calculated using the following formula: SOH = ΔW / (ΔSOC × total battery capacity) × 100%.

4. The battery charging control method according to claim 2, characterized in that, The SOC-voltage characteristic curve is obtained from the battery product manual and includes the correspondence between SOC and voltage under different temperature conditions.

5. The battery charging control method according to claim 2, characterized in that, The preset unit time t is 10 minutes.

6. The battery charging control method according to claim 1, characterized in that, In step E, based on the battery voltage just before the DC-DC converter starts operating, the total current of the vehicle's low-voltage circuit, and the output voltage and current of the DC-DC converter during operation, combined with the battery's state of health (SOH), it is determined whether the conditions for completing the charging process are met, including: Obtain the output voltage V2 at various times during the operation of the DC-DC converter. a and output current I2 a ; Obtain the battery voltage V1 just before the DCDC starts operating based on the recorded real-time battery voltage. N ; The total current I1 of the vehicle's low-voltage circuit at the moment before the DCDC starts operating is obtained based on the recorded total current of the vehicle's low-voltage circuit. N ; Based on the battery voltage V1 at the moment before the operation N Query the SOC-voltage characteristic curve for the corresponding ambient temperature to obtain the real-time SOC; The theoretically required SOC difference ΔSOC = 100% - real-time SOC; Calculate the required energy ΔW 补 =ΔSOC × Total battery capacity × SOH; Calculate the actual energy replenishment W using the following formula. 补 :

7. Among them, Δt is the minimum sampling period for voltage and current in the hardware, and N is the total number of samples; V1 N and I1 N These are the battery output voltage and output current just moments before the DC-DC converter starts operating; I2 a V2 is the output current of the DC-DC converter at time a during operation. a Let I2 be the output voltage of the DC-DC converter at time a. a-1 V2 is the output current of the DC-DC converter at time a-1. a-1 The output voltage of the DC-DC converter at time a-1 is the output voltage when it is operating. If and only if the actual energy replenishment W 补 Greater than or equal to the required energy ΔW 补 When the conditions for completing the power replenishment are met, it is determined that the conditions for completing the power replenishment are met.

8. The battery charging control method according to claim 1, characterized in that, Step E also includes a dual-mode power selection step: When the SOH is lower than the preset SOH threshold, the intelligent charging mode is activated. Based on the battery voltage just before the DC-DC converter starts working, the total current of the vehicle's low-voltage circuit, the output voltage and output current of the DC-DC converter when it is working, and the battery's health status SOH, it is determined whether the charging completion conditions are met. When the SOH is higher than or equal to the preset SOH threshold, a quantitative charging mode is adopted, and charging is performed according to the preset fixed charging energy required.

9. The battery charging control method according to claim 4, characterized in that, The preset charging completion threshold is 95%.

10. The battery charging control method according to claim 1, characterized in that, If the SOC verification still fails to reach the preset power replenishment completion threshold after three consecutive re-executions of steps D-F, the power replenishment process is interrupted.

11. A battery charging control system, characterized in that, include: The vehicle control unit (VCU) is used to control the vehicle's high-voltage power supply and the transmission of DC-DC enable signals. A battery management system (BMS) is used to manage the status of high-voltage batteries. High-voltage distribution unit (PDU) is used for high-voltage power distribution management; Low-voltage batteries are used as a source of supplementary power. Temperature sensor, used to detect ambient temperature; The DC-DC converter is connected to the high-voltage distribution cabinet PDU and the low-voltage battery respectively, and is used to charge the low-voltage battery. The DC-DC controller is communicatively connected to the VCU, the BMS, the PDU, and the temperature sensor. The DC-DC controller is configured to automatically execute the integral DC-DC intelligent power replenishment method according to any one of claims 1 to 9 after stopping and receiving the DC-DC enable signal from the VCU, thereby controlling the DC-DC to perform power replenishment.

12. A new energy engineering machinery, characterized in that, Includes the battery charging control system as described in claim 9.

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