Photoinduction self-adaptive headlight system of electric vehicle

Abstract

The invention relates to the technical field of vehicle lighting, in particular to an electric vehicle photoinduction self-adaptive headlight system which comprises a deceleration state recognition module, an illumination trend judgment module, a charge state division module, a lighting power setting module and an output control execution module. According to the method, a deceleration state identification result is established by synchronously analyzing a current change direction and a brake signal state, a continuous sampling illuminance change rate is introduced to construct a trend judgment index, a low-illuminance approaching trend is judged in combination with an illumination decline intensity and a continuous period, and then the real-time charge state of a battery is collected and affiliated to a grading label; a target output power and an adjusting rhythm are set by matching a power regulation and control strategy, a linearly or non-linearly increasing lightening power sequence is set under different electric quantity conditions, a power control result is converted into a PWM instruction to be dynamically output to a headlight driving circuit, and self-adaptive adjustment of the brightness of the headlight of the electric vehicle under the conditions of illumination decreasing and electric quantity changing is achieved.

Description

Technical Field

[0001] This invention relates to the field of vehicle lighting technology, and in particular to a light-sensing adaptive headlight system for electric vehicles. Background Technology

[0002] The field of vehicle lighting technology encompasses various devices and systems for providing visual illumination and signal indication, including headlights, taillights, turn signals, brake lights, and their automatic control, power supply, light source adjustment, and heat dissipation. It aims to improve driving safety and signal recognition accuracy at night or in low-visibility environments. Specifically, it covers research and design of light source types (such as halogen lamps, xenon lamps, and LED lamps), beam control methods, automatic sensing systems, lamp structure design and installation layout, and electrical control circuits. Among these, the electric vehicle headlight system refers to a lighting system installed at the front of an electric vehicle to provide forward illumination in low-light environments. Powered by the vehicle battery, it uses LEDs as the primary light source, limits the beam divergence angle through physical structures, and controls the lights' on / off state using manual switches or mechanical light sensors. Some systems also use motors to adjust the vertical or horizontal angle of the lamps to adapt to different road slopes or vehicle speeds. The overall system consists of a lamp housing, light source, lens assembly, and connecting circuits.

[0003] Existing electric vehicle headlight systems primarily rely on light sensors or manual switches to control the lights, lacking a comprehensive perception of vehicle operating status and environmental changes. They cannot achieve dynamic light response in low-light and sudden deceleration scenarios, making it difficult for drivers to obtain sufficient lighting support in time when the light dims. At the same time, existing systems lack effective monitoring and adjustment mechanisms for battery charge status, and cannot intelligently allocate headlight power output when the battery is low, which may accelerate power consumption or affect lighting performance. In addition, traditional systems lack the ability to judge the trend of light changes and cannot predict changes in the lighting environment, resulting in lag in headlight adjustment, reducing adaptability and driving safety in complex road conditions. Summary of the Invention

[0004] To address the technical problems existing in the prior art, this invention provides a light-sensing adaptive headlight system for electric vehicles. The technical solution is as follows: On the one hand, a light-sensing adaptive headlight system for electric vehicles is provided, including: The deceleration state recognition module reads the electric vehicle drive current change direction parameters and braking control signal status parameters, performs synchronous joint judgment operation, identifies whether the electric vehicle is currently in a deceleration state, and establishes a deceleration state judgment result. Based on the deceleration state judgment result, the illumination trend judgment module collects the illumination data of the illumination sensor in two consecutive sampling periods, calculates the illumination change rate index, judges whether there is a continuous illumination decreasing trend, and obtains the low illumination approach trend judgment result. Based on the low illumination proximity trend judgment result, the state of charge classification module collects real-time state of charge percentage data of electric vehicle batteries, performs classification judgment with the set classification threshold range, establishes level labels and maps them with the preset power control strategy table to generate charge level matching label results. The headlight power setting module, based on the power regulation strategy mapped by the charge level matching tag result, pre-matches the target power value and adjustment cycle duration, and adjusts the power accordingly according to different charge states to construct the headlight power sequence control result. The output control execution module inputs corresponding control commands to the PWM control module of the electric vehicle headlight drive circuit based on the headlight illumination power sequence control result, dynamically adjusts the headlight brightness, and outputs the adaptive adjustment result of the electric vehicle headlight.

[0005] As a further aspect of the present invention, when performing the synchronous joint judgment operation, the values ​​of the drive current in two consecutive sampling periods are collected, the difference between the values ​​is calculated and the sign is determined. If the value is negative, it indicates that the drive current is decreasing. At the same time, it is detected whether the braking control signal is in an active state. If both conditions are met, it is identified that the electric vehicle is in a deceleration state.

[0006] As a further aspect of the present invention, in the process of determining whether there is a continuous decreasing trend in illuminance, a time series of the illuminance change rate index for three or more consecutive sampling periods is constructed, all negative values ​​in the time series are extracted, and the maximum absolute value is calculated as the illuminance decrease intensity benchmark value. If the illuminance decrease intensity benchmark value is greater than the set illuminance decrease threshold, and the number of periods in which the negative slope state continuously occurs is greater than or equal to three, then it is determined that there is a continuous decreasing trend in illuminance.

[0007] As a further aspect of the present invention, when performing the attribution determination, if the percentage is greater than or equal to 70%, it is marked as a high-charge state; if the percentage is between 30% and 70%, it is marked as a medium-charge state; and if the percentage is less than 30%, it is marked as a low-charge state.

[0008] As a further aspect of the present invention, when adjusting the corresponding power, if the level label is in the high charge state, the headlight is set to be lit with a constant upper limit of output power; if the level label is in the medium charge state, within the total adjustment cycle, the initial power value is set to 50% of the constant upper limit of output power, and linearly increased at equal intervals, with a fixed step size for each time interval until the constant upper limit of output power is reached; if the level label is in the low charge state, the initial power value is set to 30% of the target upper limit of power, and the power is gradually increased in a non-linear manner.

[0009] As a further aspect of the present invention, the deceleration state recognition module includes: The drive current monitoring submodule acquires the drive current value of the electric vehicle in the current sampling period and the previous sampling period, calculates the difference in drive current change by subtracting the drive current value of the previous period from the current drive current value, and determines whether the sign of the difference in drive current change is negative. If it is negative, it is determined that the current drive current is in a downward trend and generates a drive current decreasing trend status record. The braking signal detection submodule acquires the braking control signal status parameters, determines whether the current signal is active, and if it is active, it indicates that the current braking function has been triggered and generates a braking control signal activation status identifier. The deceleration state determination submodule calls the drive current decreasing trend state record and the brake control signal activation state identifier to make a joint judgment. If the drive current shows a decreasing trend and the brake signal is in an active state, the current electric vehicle is determined to be in a deceleration state, and a deceleration state determination result is generated.

[0010] As a further aspect of the present invention, the illumination trend determination module includes: The illumination rate calculation submodule obtains the illumination data of the illumination sensor in the current and previous sampling cycles based on the deceleration state judgment result, calculates the current illumination value minus the illumination value of the previous cycle, and combines the time interval between the two sampling cycles to output the ratio as the illumination change rate index, and establishes the illumination change rate value. The decreasing intensity extraction submodule constructs a time series for the current period and the previous two periods based on the illuminance change rate value, filters all data points with negative values ​​in the time series, takes the absolute value of each negative value and compares them, and selects the maximum value as the reference benchmark for the decreasing illuminance intensity to obtain the illuminance decreasing intensity benchmark value. The trend state determination submodule calls the light intensity reduction benchmark value to determine whether it is greater than the set light intensity reduction threshold. At the same time, it counts the number of consecutive negative values ​​in the time series. If the number of cycles is greater than or equal to three, it determines that the current environment is in a state of continuous light intensity reduction and establishes a low light intensity approach trend judgment result.

[0011] As a further aspect of the present invention, the state of charge division module includes: Based on the low illumination proximity trend judgment result, the charge data acquisition submodule collects real-time state of charge percentage data of the electric vehicle battery in the current sampling period, uses the percentage value as the interval judgment input variable, and establishes the state of charge percentage value. The level range judgment submodule calls the state of charge percentage value and compares it with the set state of charge classification threshold range to determine its classification. If the percentage value is greater than or equal to 70%, it is classified as a high state of charge; if it is between 30% and 70%, it is classified as a medium state of charge; if it is less than 30%, it is classified as a low state of charge, and a state of charge level label is generated. The level strategy mapping submodule queries the power control configuration parameter item corresponding to the level label in the preset power control strategy table according to the state of charge level label, extracts the mapping result content that matches the level label, and establishes the state of charge level matching label result.

[0012] As a further aspect of the present invention, the lighting power setting module includes: Based on the charge level matching tag results, the power strategy reading submodule extracts the target power upper limit and adjustment cycle duration of the corresponding level in the power regulation strategy table, extracts the upper limit and cycle as input parameters for lighting control, and generates a target power control parameter set. The power curve generation submodule calls the target power control parameter set, determines the category corresponding to the level label, and sets a constant value as the upper limit power if it is a high charge state, sets the initial power to 50% of the upper limit value and increases linearly at equal intervals if it is a medium charge state, and sets the initial power to 30% of the upper limit value and increases it according to a non-linear law if it is a low charge state, thus obtaining the time-segmented power regulation curve. The output sequence construction submodule extracts the lighting power value for each time segment based on the segmented power control curve of the time period, and forms an ordered lighting control sequence by matching time and power one by one, outputting a continuous timing control structure and establishing the headlight lighting power sequence control result.

[0013] As a further aspect of the present invention, the output control execution module includes: Based on the headlight illumination power sequence control results, the control instruction generation submodule extracts the corresponding power values ​​at each time node, performs formatted encoding conversion, generates a digital control instruction sequence for the PWM control module, and establishes a PWM control input instruction set. The PWM signal conditioning submodule calls the PWM control input instruction set, dynamically adjusts the duty cycle of the PWM waveform according to the power value specified in the instruction, sets the pulse width parameter to correspond to the power instruction precision, forms a continuous pulse width modulation signal, and generates a PWM dynamic adjustment signal sequence. The headlight brightness output submodule drives the electric vehicle headlight circuit control unit to perform brightness change operation according to the PWM dynamic adjustment signal sequence, so that the electric vehicle headlight outputs a lighting brightness level that matches the power at each time period, and establishes the adaptive adjustment result of the electric vehicle headlight.

[0014] The beneficial effects of the technical solutions provided in the embodiments of the present invention include at least the following: By synchronously analyzing the direction of current change and the braking signal status, a deceleration state recognition result is established. A trend judgment index is constructed by continuously sampling the rate of change of illuminance. The trend of approaching low illuminance is judged by combining the decreasing intensity of illuminance and the duration period. Then, the real-time state of charge of the battery is collected and assigned to a graded label. The target output power and adjustment rhythm are set by matching the power regulation strategy. The lighting power sequence is set with linear or nonlinear increments under different power conditions. The power control result is converted into PWM command and dynamically output to the headlight drive circuit. This realizes the adaptive adjustment of the brightness of the electric vehicle headlight under the conditions of decreasing illuminance and changing power, enhances the dual perception capability of the electric vehicle headlight system of the environment and power status, and effectively improves the safety lighting performance in night or low illuminance environments. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of an electric vehicle light-sensing adaptive headlight system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of the system framework of the present invention; Figure 3 This is a flowchart of the deceleration state recognition module of the present invention; Figure 4 This is a flowchart of the illumination trend judgment module of the present invention; Figure 5 This is a flowchart of the charge state division module of the present invention; Figure 6 This is a flowchart of the lighting power setting module of the present invention; Figure 7 This is a flowchart of the output control execution module of the present invention. Detailed Implementation

[0016] The technical solution of the present invention will now be described with reference to the accompanying drawings.

[0017] In embodiments of the present invention, words such as "exemplarily," "for example," etc., are used to indicate that something is an example, illustration, or description. Any embodiment or design described as "exemplary" in the present invention should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of the word "exemplary" is intended to present the concept in a concrete manner. Furthermore, in embodiments of the present invention, the meaning expressed by "and / or" can be both, or either one.

[0018] In the embodiments of this invention, the terms "image" and "picture" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning. Similarly, the terms "of," "corresponding (relevant)," and "corresponding" may sometimes be used interchangeably. It should be noted that, without emphasizing the distinction between them, they convey the same meaning.

[0019] In this embodiment of the invention, sometimes a subscript such as W1 may be written in a non-subscript form such as W1. When the difference is not emphasized, the meaning they express is the same.

[0020] To make the technical problems, technical solutions and advantages of the present invention clearer, a detailed description will be given below in conjunction with the accompanying drawings and specific embodiments.

[0021] This invention provides a light-sensing adaptive headlight system for electric vehicles, such as... Figure 1-2 The diagram shown illustrates a light-sensing adaptive headlight system for electric vehicles. The system includes: The deceleration state recognition module reads the electric vehicle drive current change direction parameter and the braking control signal state parameter, and performs a synchronous joint judgment operation. In this operation, the value of the drive current is collected in two consecutive sampling periods, the difference between the values ​​is calculated and the sign of the difference is determined. If the difference is negative, it indicates that the drive current is decreasing. At the same time, it detects whether the braking control signal is in an active state. If both conditions are met, the electric vehicle is identified as being in a deceleration state, and a deceleration state judgment result is established. The illumination trend judgment module collects illuminance data from the illumination sensor within two consecutive sampling periods based on the deceleration state judgment result. It calculates the ratio of the difference in illuminance between the two sampling periods to the time interval as an indicator of the rate of change of illuminance. It constructs a time series of three or more consecutive sampling periods, extracts all negative values ​​in the time series, and calculates the maximum absolute value as the benchmark value of the illuminance decrease intensity. If it is greater than the set illuminance decrease threshold and the number of periods in which the negative slope state continues to appear is greater than or equal to three, it is judged that there is a continuous illuminance decrease trend, and the low illuminance approach trend judgment result is obtained. The state of charge (SCC) classification module collects real-time SCC percentage data of electric vehicle batteries based on the low-light proximity trend judgment results, and classifies them against a set classification threshold range. Specifically, when the percentage is greater than or equal to 70%, it is marked as a high SCC; when the percentage is between 30% and 70%, it is marked as a medium SCC; and when the percentage is less than 30%, it is marked as a low SCC. The module establishes a level label and maps it to a preset power control strategy table to generate SCC level matching label results. The headlight power setting module uses a power control strategy mapped by the charge level matching label results to pre-determine the target power value and adjustment cycle duration. When the charge level label is high, the headlight is set to be lit with a constant upper limit of output power. When the charge level label is medium, the initial power value is set to 50% of the constant upper limit of output power within the total adjustment cycle, and linearly increased at equal intervals, with a fixed step size for each time interval until the constant upper limit of output power is reached. When the charge level label is low, the initial power value is set to 30% of the target upper limit of power, and the power is gradually increased in a non-linear manner to construct the headlight lighting power sequence control result. The output control execution module inputs corresponding control commands to the PWM control module of the electric vehicle headlight drive circuit based on the headlight illumination power sequence control results, dynamically adjusts the headlight brightness, and outputs the adaptive adjustment results of the electric vehicle headlight.

[0022] The deceleration state judgment results include the driving current decreasing trend indicator, the braking signal activation state indicator, and the synchronization judgment establishment indicator. The low illumination approach trend judgment results include the illuminance decreasing intensity benchmark value, the number of negative slope duration cycles, and the trend identification indicator. The charge level matching label results include high charge level label, medium charge level label, and low charge level label. The headlight illumination power sequence control results include the constant power output upper limit value, linear increasing power sequence, and nonlinear increasing power sequence. The electric vehicle headlight adaptive adjustment results include the PWM control instruction set, dynamic brightness adjustment parameters, and electric vehicle headlight brightness status record.

[0023] Specifically, such as Figure 2 , 3 As shown, the deceleration state recognition module includes: The drive current monitoring submodule acquires the drive current value of the electric vehicle in the current sampling period and the previous sampling period, calculates the difference in drive current change by subtracting the drive current value of the previous period from the current drive current value, and determines whether the sign of the difference in drive current change is negative. If it is negative, it is determined that the current drive current is in a downward trend and generates a drive current decreasing trend status record. The drive current monitoring submodule uses a high-precision Hall current sensor to sample the bus input of the electric vehicle motor controller in real time. The sampling frequency is set to 100 Hz, meaning current data is collected every 10 milliseconds. During execution, the analog voltage signal fed back by the sensor at the current moment (time t) is first read, converted into a digital value by an analog-to-digital converter, and mapped to a specific current value according to the sensor's range coefficient (e.g., each volt represents 50 amperes), obtaining the drive current value for the current sampling period, for example, 55 amperes. Next, the drive current value stored in the previous sampling period (time t-1) is retrieved from the internal circular buffer; let's assume this value is 60 amperes. Then, the processor performs a subtraction operation, subtracting 60 amperes from 55 amperes, resulting in a drive current change difference of -5 amperes. This difference is compared to zero; since -5 amperes is less than zero, the difference is determined to be negative. To eliminate interference from current fluctuation noise, it is further confirmed whether the absolute value of the negative difference exceeds the preset noise tolerance value (e.g., 0.5 amperes). In this example, 5 amperes is much larger than 0.5 amperes, thus confirming that the current is in the effective decreasing range. This state is then written to the register, locking the current dynamic characteristics within the current time window and generating a record of the driving current decreasing trend.

[0024] The braking signal detection submodule acquires the braking control signal status parameters, determines whether the current signal is active, and if it is active, it indicates that the current braking function has been triggered and generates a braking control signal activation status identifier. The brake signal detection submodule polls the status register of the vehicle's brake control unit (BCU) in real time via hardwired connection or CAN bus communication. During execution, the module first reads the voltage value of the brake pedal position sensor or the digital level signal of the brake switch, and parses the brake message (Brake_Status) on the vehicle bus. Assuming the currently acquired brake switch signal is high (logic 1), or the flag bit in the brake message displays "Active," the signal is debouncing; that is, the signal is detected as active for three consecutive sampling periods (e.g., 30 milliseconds) to confirm signal stability. Once braking is confirmed, the physical signal is mapped to a logical status parameter, and this parameter is compared with a preset activation status code (e.g., 0x01). If the comparison result matches, it indicates that the driver has pressed the brake pedal or activated the regenerative braking function. At this time, the module sets the brake flag bit in the status table. This flag bit serves as the basis for subsequent logical judgments, clearly indicating that the vehicle is currently performing a braking operation, thereby generating a brake control signal activation status identifier.

[0025] The deceleration state determination submodule calls the drive current decreasing trend state record and the brake control signal activation state identifier to make a joint judgment. If the drive current shows a decreasing trend and the brake signal is in an active state, the current electric vehicle is determined to be in a deceleration state, and a deceleration state determination result is generated. The deceleration state determination submodule establishes a logic AND operation unit. The two inputs of this unit are connected to the output register of the drive current decreasing trend state record and the status bit of the brake control signal activation status identifier, respectively. During logic judgment, the module first reads the drive current record and checks if it is marked "True" (i.e., a decreasing trend exists), and simultaneously reads the brake signal identifier and checks if it is marked "Active" (i.e., brake activation). Only when both conditions are met simultaneously—that is, the current is decreasing and the brake signal is valid—does the logic unit output a high-level signal. For example, in a certain detection, the drive current shows a decrease of five amperes every ten milliseconds, and the brake signal bit is 1, indicating that the electric vehicle is undergoing deceleration caused by the driver's active braking, rather than simple coasting or uphill resistance deceleration. Based on this dual confirmation mechanism, the current vehicle motion state is classified as "active deceleration," and the judgment result is encapsulated into a structured data packet containing a timestamp and state type to generate the deceleration state judgment result.

[0026] Specifically, such as Figure 2 , 4 As shown, the illumination trend judgment module includes: The illumination rate calculation submodule obtains the illuminance data of the light sensor in the current and previous sampling periods based on the deceleration state judgment result, calculates the current illuminance value minus the illuminance value of the previous period, and combines the time interval between the two sampling periods to output the ratio as the illuminance change rate index and establishes the illuminance change rate value. After determining that the electric vehicle is decelerating, the illuminance rate calculation submodule activates the illuminance sensor array and synchronously collects ambient illuminance data according to a preset sampling period (e.g., every 200 milliseconds). During execution, the module reads the illuminance value of the current sampling period (t), for example, 1,500 lux, and reads the value stored in the previous sampling period (t-1), for example, 1,800 lux. It performs arithmetic subtraction, subtracting 1,500 from 1,800, resulting in an illuminance difference of -300 lux. Simultaneously, it obtains the time interval constant between the two sampling points, i.e., 0.2 seconds. Subsequently, the module performs division, dividing -300 lux by 0.2 seconds to calculate the illuminance change rate as -1,500 lux per second. This value quantifies the rate at which the ambient light dims. To comprehensively analyze illuminance changes, the calculated rate values ​​are stored in a first-in-first-out (FIFO) queue. Table 1 below shows the illuminance acquisition and rate calculation data for three consecutive sampling periods. These calculated rate data were formatted and stored as the basis for subsequent trend analysis to establish the illuminance change rate value.

[0027] Table 1 Illuminance Acquisition and Rate Calculation Table Sampling period number Current illuminance (lux) Illuminance in the previous cycle (lux) Time interval (seconds) Rate of change (lux / second) T-2 2100 2300 0.2 -1000 T-1 1800 2100 0.2 -1500 T-0 1500 1800 0.2 -1500 As shown in Table 1, the data demonstrates the rapid decrease in illuminance over time. The calculated rate of change is negative, reflecting the physical fact that the ambient light dims rapidly. Based on this, the output ratio is used as an indicator of the rate of change of illuminance.

[0028] The decreasing intensity extraction submodule constructs a time series of the current period and the previous two periods based on the rate of change of illuminance. It filters out all data points with negative values ​​in the time series, takes the absolute value of each negative value and compares them. The maximum value is selected as the reference benchmark for the decreasing intensity of illuminance, thus obtaining the reference value for the decreasing intensity of illuminance. The decreasing intensity extraction submodule accesses the FIFO queue storing the rate of change of illuminance values, extracts the rate data for the current period (T-0) and the previous two periods (T-1, T-2), and constructs a time series array of length three, namely [-1500, -1500, -1000]. During execution, the array is traversed, filtering out all values ​​with negative signs; if a positive value is encountered, it is discarded or set to zero. For the filtered set of negative values, the absolute value function is called one by one to convert them, resulting in a positive value sequence [1500, 1500, 1000]. Subsequently, the module executes a maximum value search algorithm, comparing all values ​​in the sequence: first, comparing 1500 with 1500, taking 1500; then comparing 1500 with 1000, finally determining the maximum value as 1500. This maximum value represents the intensity index at the moment when the ambient light decreases most drastically within the last three sampling periods. This value is locked and defined as the core parameter for measuring the degree of current ambient light deterioration, serving as the direct input for subsequent threshold determination, thus obtaining the baseline value for the decreasing illuminance intensity.

[0029] The trend state determination submodule calls the illuminance decrease intensity benchmark value to determine whether it is greater than the set illuminance decrease threshold. At the same time, it counts the number of consecutive negative values ​​in the time series. If the number of cycles is greater than or equal to three, it determines that the current environment is in a state of continuous illuminance decrease and establishes a low illuminance approach trend judgment result. The trend state determination submodule first loads a preset illuminance decrease threshold, which was determined through numerous tunnel entry experiments and is set to 800 lux per second. This means that when the illuminance decrease rate exceeds this value, there is a high probability that the vehicle has entered a tunnel or culvert. During execution, the module compares the illuminance decrease intensity baseline value (1500) obtained in the previous step with the set threshold (800). Since 1500 is greater than 800, the first determination condition is met. Next, the module counts the number of negative values ​​in the time series array [-1500, -1500, -1000], confirming that there are three. This statistical value is compared with the preset threshold for the number of consecutive periods (three) to determine whether it is greater than or equal to three. In this example, the condition is met, indicating that the illuminance is in a decreasing trend for 0.6 seconds. Combining the determination results of the two conditions: the intensity exceeds the threshold and the trend is continuous, it is confirmed that the vehicle is in the process of rapidly entering a low-illuminance area (such as a tunnel entrance), and a low-illuminance proximity sign is immediately set to establish a low-illuminance proximity trend determination result.

[0030] Specifically, such as Figure 2 , 5 As shown, the state-of-charge (SOC) partitioning module includes: Based on the low illumination proximity trend judgment result, the charge data acquisition submodule collects real-time state of charge percentage data of electric vehicle battery under the current sampling period, uses the percentage value as the interval judgment input variable, and establishes the state of charge percentage value. Upon receiving the trigger signal indicating an approaching low-light trend, the charge data acquisition submodule immediately sends a status query request frame to the Battery Management System (BMS) via the CAN bus. The BMS responds by returning a data packet containing the current total battery voltage, current, and an estimated state of charge (SOC). The module parses this data packet, extracting the SOC byte, which is typically an integer between 0 and 100, representing the percentage of remaining battery capacity. For example, a real-time value of 65 indicates that the current remaining battery capacity is 65%. To ensure data accuracy, the module performs range verification on the acquired value, confirming it falls within the valid range of 0 to 100. If the data is valid, the value (65%) is temporarily stored in volatile memory as a basis for subsequent classification judgments. This process achieves a data transition from environmental perception to energy management, transforming physical electricity into a decision variable and establishing a state of charge percentage value.

[0031] The level range judgment submodule calls the state of charge percentage value and compares it with the set state of charge classification threshold range to determine its classification. If the percentage value is greater than or equal to 70%, it is classified as a high state of charge; if it is between 30% and 70%, it is classified as a medium state of charge; if it is less than 30%, it is classified as a low state of charge, and a state of charge level label is generated. The level range judgment submodule reads the temporarily stored state of charge percentage value (65%) and loads the pre-set level threshold parameters in non-volatile memory. The preset threshold ranges are defined as follows: high charge range is [70%, 100%], medium charge range is [30%, 70%), and low charge range is [0%, 30%). During execution, 65 is first compared with 70. 65 is less than 70, therefore it does not belong to the high charge state. Then, 65 is compared with 30, and combined with the judgment result of less than 70, it is confirmed that the value falls within the half-open and half-closed range of 30 to 70. According to the range definition, the current battery state is determined to belong to "medium charge state". Then, the corresponding level code (e.g., Level_2) is generated. This code is used as an index key value for subsequent strategy table lookup. This step discretizes the continuous analog quantity (charge percentage) into three specific control levels, providing a logical basis for differentiated power allocation and generating charge state level labels.

[0032] The level strategy mapping submodule queries the power control configuration parameter items corresponding to the level labels in the preset power control strategy table based on the state of charge level labels, extracts the mapping result content that matches the level labels, and establishes the state of charge level matching label result. The level-based policy mapping submodule accesses the power regulation policy table pre-stored in the microcontroller's Flash space based on the generated state of charge level label (Level_2). This table is a structured key-value database, with each row corresponding to a state of charge level and its associated control parameters. During execution, the module searches using "medium state of charge" as the index keyword to match the corresponding policy row. As shown in Table 2 below, this table details the power regulation configurations corresponding to different state of charge levels.

[0033] Table 2 Power Regulation Strategy Table Charge rating label Target power upper limit (watt) Adjustment cycle duration (Second) Curve Type | Initial Power Ratio | High Charge State | 45 | 1.0 | Constant / Step | 100% | Medium Charge State | 40 | 2.0 | Linear Increasing | 50% | Low Charge State | 25 | 3.0 | Nonlinear / Exponential | 30% As shown in Table 2, the configuration items corresponding to the medium charge state are extracted: the target power limit is 40 watts, the adjustment period is 2 seconds, the curve type is linearly increasing, and the initial ratio is 50%. These parameters are packaged and loaded into the policy runtime memory area, completing the mapping from state labels to specific control parameters and establishing the charge level matching label results.

[0034] Specifically, such as Figure 2 , 6 As shown, the lighting power setting module includes: The power strategy reading submodule extracts the target power upper limit and adjustment cycle duration of the corresponding level from the power regulation strategy table based on the charge level matching tag results, and uses the upper limit and cycle as input parameters for lighting control to generate a target power control parameter set. The power strategy reading submodule unpacks the strategy data packet extracted in the previous step. During execution, the module reads the target power upper limit variable and assigns it a value of 40 watts; it reads the adjustment cycle duration variable and assigns it a value of 2 seconds; and it extracts the initial power ratio parameter (0.5). The initial power value is calculated using arithmetic multiplication: 40 watts multiplied by 0.5 equals 20 watts. Next, the time step is defined, for example, setting the control update frequency to 10 Hz, i.e., a time step of 0.1 seconds. Based on the adjustment cycle of 2 seconds and the time step of 0.1 seconds, the total number of adjustment steps is calculated to be 20 steps. These specific values ​​(initial power 20W, final power 40W, total steps 20) are identified as the core boundary conditions for generating the specific control curve, ensuring that the subsequent lighting process strictly follows the battery's energy supply capacity, and generating the target power control parameter set.

[0035] The power curve generation submodule calls the target power control parameter set, determines the category corresponding to the level label, and sets a constant value as the upper limit power if it is a high charge state, sets the initial power to 50% of the upper limit value and increases linearly at equal intervals if it is a medium charge state, and sets the initial power to 30% of the upper limit value and increases it according to a non-linear law if it is a low charge state, thus obtaining the time-segmented power regulation curve. The power curve generation submodule performs specific interpolation calculations based on the target power control parameter set to generate the power curve. Given the current condition is determined to be a medium-load state, an equal-interval linear incremental algorithm (i.e., a linear function) is used. First, calculate the power increment slope k: subtract the initial power of 20 watts from the final power of 40 watts to obtain a difference of 20 watts; then divide the difference by the total number of steps of 20 steps to obtain a power increment of 1 watt for each step. Perform the iterative calculation process: the power in step 0 is the initial value of 20 watts; the power in step 1 is 20 plus one, i.e., 21 watts; the power in step 2 is 22 watts; and so on, until the upper limit of 40 watts is reached in step 20. If it is determined to be a high-charge state, a constant sequence of 45 watts is directly generated throughout the entire time period; if it is a low-charge state, an exponential function (such as...) is used. The module calculates the power value at each time point, ensuring a slow increase in the early stages and a rapid increase in the later stages to mitigate the instantaneous impact on the battery. In this example, the module ultimately generates a linearly increasing array containing twenty-one data points, resulting in a segmented power regulation curve for each time period.

[0036] The output sequence construction submodule extracts the lighting power value of each time segment according to the segmented power control curve of the time period, and forms an ordered lighting control sequence by matching time and power one by one, outputs a continuous timing control structure, and establishes the headlight lighting power sequence control result. The output sequence construction submodule strictly aligns the calculated power value array with the time axis to construct a timing control table. During execution, the module creates a two-dimensional array containing two columns: "timestamp" and "power value". The first row records (T=0.0s, Power=20W), the second row records (T=0.1s, Power=21W), ..., and the last row records (T=2.0s, Power=40W). To adapt to the input requirements of the subsequent PWM controller, the power values ​​also need to be normalized or quantized. Assuming the maximum rated power of the lamp is fifty watts, the corresponding PWM duty cycle is 100% (or a digital value of 255), and the power value at each step is converted into the corresponding digital value. For example, 20W corresponds to a ratio of 0.4, which is converted to the digital value 255 multiplied by 0.4 equals 102 (rounded down); 40W corresponds to a ratio of 0.8, which is converted to 204. Table 3 below shows a portion of the constructed output sequences.

[0037] Table 3. Headlight Power Control Sequence Table (Partial) Time point (seconds) Target power (watts) Normalized ratio Digital control values ​​(0-255) 0.0 20 0.40 102 0.5 25 0.50 127 1.0 30 0.60 153 1.5 35 0.70 178 2.0 40 0.80 204 As shown in Table 3, in this way, the module outputs a set of control command streams that are continuous in time and precisely correspond in value, ensuring that the changes in headlight brightness completely conform to the preset strategy curve and establishing the headlight lighting power sequence control result.

[0038] Specifically, such as Figure 2 , 7 As shown, the output control execution module includes: The control instruction generation submodule extracts the corresponding power values ​​at each time node based on the headlight illumination power sequence control results, performs formatted encoding conversion, generates a digital control instruction sequence for the PWM control module, and establishes a PWM control input instruction set. The control instruction generation submodule is responsible for converting the abstract digital quantities in the headlight illumination power sequence control results into register operation instructions at the microcontroller's lower level. During execution, the module traverses each time point in the sequence list, extracting the corresponding digital control quantity (e.g., 102 at T=0.0s). It constructs a data frame according to the PWM controller's communication protocol. The data frame includes a frame header, a channel address (pointing to the headlight drive channel), a data payload (value 102), and a checksum. For example, the generated instruction code is "0xAA0x010x660xCS", where 0xAA is the frame header, 0x01 is the channel number, and 0x66 is the hexadecimal representation of 102. These instructions are stored sequentially in a direct memory access (DMA) buffer or in the interrupt service routine's send queue, ensuring that one instruction is accurately triggered every 0.1 seconds, thus establishing the PWM control input instruction set.

[0039] The PWM signal conditioning submodule calls the PWM control input instruction set, dynamically adjusts the duty cycle of the PWM waveform according to the power value specified in the instruction, sets the pulse width parameter to correspond to the power instruction precision, forms a continuous pulse width modulation signal, and generates a PWM dynamic adjustment signal sequence. The PWM signal conditioning submodule directly controls the hardware timer / counter unit, dynamically adjusting the output waveform according to the input instruction set. During execution, the PWM base frequency is set to 1 kHz, i.e., the period is one millisecond. For the first data (102) in the instruction set, the module calculates the high-level duration: divide 102 by 255 (total resolution), then multiply by one millisecond to obtain 0.4 milliseconds. The module writes this time value into the Compare-Capture Register (CCR). As the counter runs, when the count value is less than the CCR value, the output is high; otherwise, it toggles to low, thus generating a square wave signal with a duty cycle of 40%. In the next time step (after 0.1 seconds), the module reads the next instruction (127), recalculates and updates the register, adjusting the duty cycle to 50%. This cycle repeats, and the module continuously adjusts the pulse width twenty times within two seconds, forming a continuous pulse width modulation signal with a duty cycle smoothly transitioning from 40% to 80%, generating a PWM dynamic adjustment signal sequence.

[0040] The headlight brightness output submodule drives the electric vehicle headlight circuit control unit to perform brightness change operation according to the PWM dynamic adjustment signal sequence, so that the electric vehicle headlight outputs a lighting brightness level that matches the power at each time period, and establishes the adaptive adjustment result of the electric vehicle headlight. The headlight brightness output submodule receives the electrical signal from the PWM signal adjustment submodule and applies it to the gate of the power MOSFET in the headlight drive circuit. During execution, when the PWM signal is high, the MOSFET is turned on, the battery voltage is applied to the LED headlight terminals, generating current and emitting light; when the signal is low, the MOSFET is turned off, and the current is interrupted. Because the PWM frequency is as high as 1 kHz, far exceeding the persistence of vision frequency of the human eye, the human eye perceives not flicker, but a change in average brightness. During the time period from T=0 to T=2.0 seconds, as the PWM duty cycle linearly increases from 40% to 80%, the average effective current flowing through the headlight also increases linearly. Ultimately, the actual output luminous flux of the electric vehicle headlight smoothly increases from the initial approximately 800 lumens to 1600 lumens (assuming a maximum luminous flux of 2000 lumens), achieving a "gradual brightening" lighting effect that matches the mid-charge state strategy, effectively avoiding sudden drops in battery voltage, and establishing an adaptive adjustment result for the electric vehicle headlight.

[0041] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of protection of the described technical solutions.

Claims

1. A light-sensing adaptive headlight system for electric vehicles, characterized in that, include: The deceleration state recognition module reads the electric vehicle drive current change direction parameters and braking control signal status parameters, performs synchronous joint judgment operation, identifies whether the electric vehicle is currently in a deceleration state, and establishes a deceleration state judgment result. Based on the deceleration state judgment result, the illumination trend judgment module collects the illumination data of the illumination sensor in two consecutive sampling periods, calculates the illumination change rate index, judges whether there is a continuous illumination decreasing trend, and obtains the low illumination approach trend judgment result. Based on the low illumination proximity trend judgment result, the state of charge classification module collects real-time state of charge percentage data of electric vehicle batteries, performs classification judgment with the set classification threshold range, establishes level labels and maps them with the preset power control strategy table to generate charge level matching label results. The headlight power setting module, based on the power regulation strategy mapped by the charge level matching tag result, pre-determines the target power value and adjustment cycle duration, and adjusts the power accordingly according to different charge states to construct the headlight power sequence control result. The output control execution module inputs corresponding control commands to the PWM control module of the electric vehicle headlight drive circuit based on the headlight illumination power sequence control result, dynamically adjusts the headlight brightness, and outputs the adaptive adjustment result of the electric vehicle headlight.

2. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that: When performing the synchronous joint judgment operation, the values ​​of the drive current in two consecutive sampling periods are collected, the difference between the values ​​is calculated and the sign is determined. If the value is negative, it indicates that the drive current is decreasing. At the same time, it is detected whether the braking control signal is in an active state. If both conditions are met, it is identified that the electric vehicle is in a deceleration state.

3. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that: In the process of determining whether there is a continuous decreasing trend in illuminance, a time series of the illuminance change rate index for three or more consecutive sampling periods is constructed. All negative values ​​in the time series are extracted, and the maximum absolute value is calculated as the illuminance decrease intensity benchmark value. If the illuminance decrease intensity benchmark value is greater than the set illuminance decrease threshold, and the number of periods in which the negative slope state continues to appear is greater than or equal to three, then it is determined that there is a continuous decreasing trend in illuminance.

4. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that: When performing the attribution determination, if the percentage is greater than or equal to 70%, it is marked as a high-charge state; if the percentage is between 30% and 70%, it is marked as a medium-charge state; and if the percentage is less than 30%, it is marked as a low-charge state.

5. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that: When adjusting the power accordingly, if the level label indicates a high charge state, the headlights are set to illuminate with a constant upper limit of output power. If the level label indicates a medium charge state, within the total adjustment cycle, the initial power value is set to 50% of the constant upper limit of output power, and linearly increased at equal intervals, with a fixed step size for each time interval until the constant upper limit of output power is reached. If the level label indicates a low charge state, the initial power value is set to 30% of the target upper limit of power, and the power is gradually increased in a non-linear manner.

6. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that, The deceleration state recognition module includes: The drive current monitoring submodule acquires the drive current values ​​of the electric vehicle in the current sampling period and the previous sampling period, calculates the difference in drive current change by subtracting the drive current value from the drive current value of the previous period, and determines whether the sign of the difference in drive current change is negative. If it is negative, it is determined that the current drive current is in a downward trend and generates a drive current decreasing trend status record. The braking signal detection submodule acquires the braking control signal status parameters, determines whether the current signal is active, and if it is active, it indicates that the current braking function has been triggered and generates a braking control signal activation status identifier. The deceleration state determination submodule calls the driving current decreasing trend state record and the braking control signal activation state identifier to make a joint judgment. If the driving current shows a decreasing trend and the braking signal is in an active state, the current electric vehicle is determined to be in a deceleration state, and a deceleration state determination result is generated.

7. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that, The illumination trend determination module includes: The illumination rate calculation submodule obtains the illumination data of the illumination sensor in the current and previous sampling cycles based on the deceleration state judgment result, calculates the current illumination value minus the illumination value of the previous cycle, and combines the time interval between the two sampling cycles to output the ratio as the illumination change rate index, and establishes the illumination change rate value. The decreasing intensity extraction submodule constructs a time series of the current period and the previous two periods based on the illuminance change rate value, filters all data points with negative values ​​in the time series, takes the absolute value of each negative value and compares them, and selects the maximum value as the reference benchmark for the decreasing illuminance intensity to obtain the illuminance decreasing intensity benchmark value. The trend state determination submodule calls the light intensity reduction benchmark value to determine whether it is greater than the set light intensity reduction threshold. At the same time, it counts the number of consecutive negative values ​​in the time series. If the number of cycles is greater than or equal to three, it determines that the current environment is in a state of continuous light intensity reduction and establishes a low light intensity approach trend judgment result.

8. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that, The state of charge division module includes: Based on the low illumination proximity trend judgment result, the charge data acquisition submodule collects real-time state of charge percentage data of the electric vehicle battery under the current sampling period, uses the percentage value as the interval judgment input variable, and establishes the state of charge percentage value. The level range judgment submodule calls the state of charge percentage value and compares it with the set state of charge classification threshold range to determine its classification. If the percentage value is greater than or equal to 70%, it is classified as a high state of charge; if it is between 30% and 70%, it is classified as a medium state of charge; if it is less than 30%, it is classified as a low state of charge, and a state of charge level label is generated. The level strategy mapping submodule queries the power control configuration parameter item corresponding to the level label in the preset power control strategy table according to the state of charge level label, extracts the mapping result content that matches the level label, and establishes the state of charge level matching label result.

9. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that, The lighting power setting module includes: Based on the charge level matching tag results, the power strategy reading submodule extracts the target power upper limit and adjustment cycle duration of the corresponding level in the power regulation strategy table, extracts the upper limit and cycle as input parameters for lighting control, and generates a target power control parameter set. The power curve generation submodule calls the target power control parameter set, determines the category corresponding to the level label, and sets a constant value as the upper limit power if it is a high charge state, sets the initial power to 50% of the upper limit value and increases linearly at equal intervals if it is a medium charge state, and sets the initial power to 30% of the upper limit value and increases it according to a non-linear law if it is a low charge state, thus obtaining the time-segmented power regulation curve. The output sequence construction submodule extracts the lighting power value for each time segment based on the segmented power control curve of the time period, and forms an ordered lighting control sequence by matching time and power one by one, outputting a continuous timing control structure and establishing the headlight lighting power sequence control result.

10. The electric vehicle light-sensing adaptive headlight system according to claim 1, characterized in that, The output control execution module includes: Based on the headlight illumination power sequence control results, the control instruction generation submodule extracts the corresponding power values ​​at each time node, performs formatted encoding conversion, generates a digital control instruction sequence for the PWM control module, and establishes a PWM control input instruction set. The PWM signal conditioning submodule calls the PWM control input instruction set, dynamically adjusts the duty cycle of the PWM waveform according to the power value specified in the instruction, sets the pulse width parameter to correspond to the power instruction precision, forms a continuous pulse width modulation signal, and generates a PWM dynamic adjustment signal sequence. The headlight brightness output submodule drives the electric vehicle headlight circuit control unit to perform brightness change operation according to the PWM dynamic adjustment signal sequence, so that the electric vehicle headlight outputs a lighting brightness level that matches the power at each time period, and establishes the adaptive adjustment result of the electric vehicle headlight.

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