An LED control method, device, electronic device and storage medium

Abstract

The present application provides an LED control method, device, electronic device and storage medium, relating to the technical field of LED control. The key points of the technical solution are as follows: The method includes: when the visibility is lower than a threshold, obtaining the real-time working parameters of the LED signal lamp group; dividing the dimming cycle into a dimming window, a detection window and a protection window according to the real-time working parameters; within the dimming window, performing dynamic dimming operations and suppressing the triggering of overload protection; within the detection window, performing fault scanning; within the protection window, calculating a dynamic overload protection threshold according to the data of the dimming window and the detection window; and performing overload protection on the LED signal lamp group according to the dynamic overload protection threshold. The LED control method, device, electronic device and storage medium provided by the present application have the advantage of being able to avoid misoperation of overload protection caused by increased brightness.

Description

Technical Field

[0001] This application relates to the field of LED control technology. Specifically, it relates to an LED control method, device, electronic device, and storage medium. Background Art

[0002] In the complex road network of multiple intersections in the city, the traffic signal system faces multiple challenges. The existing traffic signal protection circuit has defects under special weather conditions. When visibility decreases due to factors such as heavy rain and fog, the LED light group needs to increase its brightness to ensure visibility. However, the increase in brightness may trigger the malfunction of the overload protection module with a fixed threshold, affecting the normal operation of the signal light. In addition, there may be a timing conflict between the pulse width modulation signal of the dynamic dimming circuit and the pulse detection of the protection circuit, further affecting the stability of the system operation.

[0003] In terms of fault detection, the existing circuit is prone to false alarms when the brightness changes suddenly, resulting in the activation of unnecessary protection mechanisms. The superposition of multiple protection mechanisms will also cause a sharp increase in system power consumption, exceeding the original design limit. The traditional solution uses independent redundant modules to process the dimming, protection, and detection functions respectively. Although the functions are separated, the circuit structure is complex and it is difficult to meet the strict requirements of signal interruption limits.

[0004] Under extreme weather conditions, on the one hand, it is necessary to dynamically enhance visibility to ensure traffic safety, on the other hand, it is necessary to achieve precise fault isolation, and at the same time, maintain the stability of the overall system power consumption.

[0005] In view of the above problems, the existing technology urgently needs to be improved. Summary of the Invention

[0006] The purpose of this application is to provide an LED control method, device, electronic device, and storage medium, which has the advantages of being able to avoid the malfunction of overload protection caused by increased brightness under special weather conditions, and realizing dynamic dimming and precise fault isolation.

[0007] In a first aspect, this application provides an LED control method for controlling an LED signal light group in the case of decreased visibility. The technical solution is as follows:

[0008] The method includes:

[0009] When the visibility is lower than the threshold, obtain the real-time working parameters of the LED signal light group;

[0010] According to the real-time working parameters, divide the dimming period into a dimming window, a detection window, and a protection window;

[0011] Within the dimming window, perform dynamic dimming operations and suppress the triggering of overload protection;

[0012] Within the detection window, perform a fault scan;

[0013] Within the protection window, calculate the dynamic overload protection threshold according to the data of the dimming window and the detection window;

[0014] According to the dynamic overload protection threshold, perform overload protection on the LED signal lamp group.

[0015] Further, in the present application, the step of dividing the dimming cycle into a dimming window, a detection window, and a protection window according to the real-time working parameters includes:

[0016] Obtain the current change rate and voltage fluctuation parameter of the LED signal lamp group;

[0017] Based on the current change rate and voltage fluctuation parameter, determine the timing allocation rule of each functional window;

[0018] According to the timing allocation rule, divide the dimming cycle into an isolated dimming window, a detection window, and a protection window.

[0019] Further, in the present application, the step of determining the timing allocation rule of each functional window based on the current change rate and voltage fluctuation parameter includes:

[0020] Calculate the degree of deviation from the preset threshold based on the obtained current change rate and voltage fluctuation parameter;

[0021] According to the degree of deviation from the preset threshold, determine the priority relationship between the dimming window and the detection window;

[0022] When the current change rate exceeds the first critical value, preferentially extend the duration of the dimming window and shorten the duration of the detection window;

[0023] When the voltage fluctuation parameter exceeds the second critical value, preferentially allocate the duration of the protection window and dynamically compress the proportion of the dimming window;

[0024] Generate a dynamic timing allocation rule based on the priority relationship.

[0025] Further, in the present application, the steps of the method further include:

[0026] When the current change rate and the voltage fluctuation parameter both exceed their respective critical values, calculate a dimming urgency index reflecting the degree of visibility decline and a protection urgency index reflecting the circuit safety risk;

[0027] Compare the dimming urgency index with the protection urgency index, and dynamically adjust the window allocation according to the comparison result:

[0028] When the dimming urgency index is higher, preferentially extend the dimming window and compress the protection window;

[0029] When the protection urgency index is higher, suspend the current dimming operation and immediately start the protection window;

[0030] When both the current change rate and the voltage fluctuation parameter do not exceed the critical value, allocate the duration of each window according to a preset ratio, and at the same time ensure that the detection window duration is not less than the safety threshold.

[0031] Further, in the present application, the step of calculating the dynamic overload protection threshold according to the data of the dimming window and the detection window includes:

[0032] Obtain the current data I(t), voltage data V(t) within the dimming window, and the fault feature data F(t) within the detection window;

[0033] Obtain the current visibility Vis, historical fault data H(t), and preset safety parameter S;

[0034] Set the basic protection threshold Pbase, emergency threshold Visemerg, emergency mode coefficient β, normal mode coefficient γ, and historical fault influence attenuation coefficient λ;

[0035] When the current visibility Vis is less than the emergency threshold Visemerg, enter the emergency mode and perform the following steps:

[0036] Calculate the current change rate ΔI(t)=(I(t)-Iavg) / Iavg, where Iavg is the historical average current;

[0037] Calculate the voltage change rate ΔV(t)=(V(t)-Vavg) / Vavg, where Vavg is the historical average voltage;

[0038] Calculate the dynamic correction coefficient:

[0039] α(t)=1+β*(ΔI(t)+ΔV(t)-F(t)-(1-Vis / Visemerg))*exp(-λH(t));

[0040] Calculate the dynamic overload protection threshold Pth(t)=Pbase*α(t)*S in the emergency mode;

[0041] When the current visibility Vis is greater than or equal to the emergency threshold Visemerg, enter the normal mode and perform the following steps:

[0042] Calculate the current change rate ΔI(t)=(I(t)-Iavg) / Iavg;

[0043] Calculate the dynamic overload protection threshold Pth(t)=Pbase*(1+γ*ΔI(t)) in the normal mode;

[0044] Apply the calculated dynamic overload protection threshold Pth(t) to the overload protection of the LED signal light group.

[0045] Furthermore, in this application, the step of performing the overload protection of the LED signal light group according to the dynamic overload protection threshold includes:

[0046] When the real-time working current exceeds the dynamic overload protection threshold, determine the overload response coefficient according to the deviation degree between the current visibility parameter and the threshold;

[0047] Based on the overload response coefficient and the exceeding amplitude of the real-time working current, select and execute the corresponding dynamic protection measures, and the dynamic protection measures include at least one of current regulation, circuit switching, and load optimization operations;

[0048] When implementing the dynamic protection measures, synchronously monitor the change trend of visibility;

[0049] When the real-time working current drops back to the dynamic overload protection threshold and the visibility parameter returns to the safe range, gradually restore the working state of the LED signal light group according to the preset recovery curve.

[0050] Furthermore, in this application, the steps of this method further include:

[0051] During the process of extending the dimming window, continuously monitor the remaining time of the protection window;

[0052] When it is detected that the remaining time of the protection window is lower than the preset minimum protection threshold, start the window compensation control:

[0053] Obtain the current visibility decrease rate and the circuit temperature parameter;

[0054] Based on the composite relationship between the visibility decrease rate and the temperature parameter, calculate the maximum allowable extension amplitude of the dimming window;

[0055] In the next dimming cycle, reallocate the duration of each function window according to the maximum allowable extension amplitude of the dimming window;

[0056] When the protection window time of three consecutive dimming cycles is lower than the minimum protection threshold, forcibly insert an independent protection period.

[0057] In a second aspect, this application also proposes an LED control device for controlling an LED signal light group in the case of decreasing visibility, and the device includes:

[0058] A parameter acquisition module, configured to acquire the real-time working parameters of the LED signal light group when the visibility is lower than the threshold;

[0059] A timing division module, configured to divide a dimming period into a dimming window, a detection window, and a protection window according to the real-time working parameters;

[0060] A dimming control module, configured to perform a dynamic dimming operation and suppress the triggering of overload protection within the dimming window;

[0061] A fault detection module, configured to perform a fault scan within the detection window;

[0062] A threshold calculation module, configured to calculate a dynamic overload protection threshold according to the data of the dimming window and the detection window within the protection window;

[0063] A protection execution module, configured to perform overload protection on the LED signal lamp group according to the dynamic overload protection threshold.

[0064] In a third aspect, the present application further provides an electronic device, including a processor and a memory, where the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the steps in the above method are run.

[0065] In a fourth aspect, the present application further provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, the steps in the above method are run.

[0066] As can be seen from the above, a LED control method, device, electronic device, and computer-readable storage medium provided by the present application solve the conflict problem between the brightness increase of the LED lamp group and the misoperation of overload protection in the prior art by dynamically adjusting the dimming, detection, and protection mechanisms of the LED signal lamp group when the visibility decreases. It can avoid the misoperation of overload protection caused by the brightness increase under special weather conditions, realize dynamic dimming and precise fault isolation, and at the same time keep the system power consumption stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0067] Figure 1 It is a schematic flowchart of a LED control method provided by the present application.

[0068] Figure 2 It is a schematic structural diagram of a LED control device provided by the present application.

[0069] In the figure: 210, a parameter acquisition module; 220, a timing division module; 230, a dimming control module; 240, a fault detection module; 250, a threshold calculation module; 260, a protection execution module. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0070] The technical solutions in the present application will be clearly and completely described below with reference to the accompanying drawings in the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The components of the present application described and illustrated in the drawings here can be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of the present application provided in the drawings is not intended to limit the scope of the present application claimed, but only represents the selected embodiments of the present application. All other embodiments obtained by those skilled in the art based on the embodiments of the present application without creative efforts belong to the scope of protection of the present application.

[0071] It should be noted that: similar reference numerals and letters denote similar items in the following drawings. Therefore, once an item is defined in one drawing, it does not need to be further defined and explained in subsequent drawings. At the same time, in the description of the present application, terms such as "first", "second", etc. are only used for distinguishing descriptions and cannot be understood as indicating or implying relative importance.

[0072] In the complex road network of multiple intersections in the city, the LED traffic signal light system faces the technical challenge of how to effectively control when the visibility decreases. When the visibility decreases, the LED lamp group needs to increase the brightness to ensure visibility, but this increase in brightness may trigger the malfunction of the overload protection module with a fixed threshold. At the same time, there may be a timing conflict between the pulse width modulation signal of the dynamic dimming circuit and the pulse detection of the protection circuit. In addition, the fault detection circuit is prone to false alarms when the brightness changes suddenly, and the superposition of multiple protection mechanisms leads to a sharp increase in system power consumption. These problems directly affect the reliability, stability, and energy efficiency performance of the LED signal lamp group under low visibility conditions.

[0073] For example, there is a key intersection equipped with an LED traffic signal lamp group. This system adopts a traditional fixed-threshold overload protection mechanism and independent dimming, protection, and detection modules. When encountering heavy rain weather and the visibility drops sharply to below 50 meters, the system automatically triggers the brightness increase mode. The LED drive current rapidly increases from the normal operating 700 mA to 1200 mA to enhance the visibility of the signal lamp. However, this sudden increase in current may trigger the overload protection threshold fixed at 1000 mA, causing the protection circuit to malfunction and cut off the power supply to the LED lamp group. At the same time, the dynamic dimming module is performing pulse width modulation at a frequency of 1 kHz, while the sampling frequency of the protection circuit is 500 Hz, and the timing mismatch between the two causes signal interference. In addition, the fault detection module detects the sudden change in current and misjudges it as a short-circuit fault, further activating the standby circuit, resulting in the system power consumption increasing suddenly from the original 100 W to 180 W. This complex interaction causes the signal lamp to flicker, go out, or even completely fail at a critical moment, seriously affecting traffic safety and traffic efficiency.

[0074] In response to this, with reference to Figure 1 , this application proposes an LED control method for controlling an LED signal light group in the case of decreased visibility. The method includes:

[0075] S110. When the visibility is lower than the threshold, obtain the real-time working parameters of the LED signal light group;

[0076] S120. According to the real-time working parameters, divide the dimming period into a dimming window, a detection window, and a protection window;

[0077] S130. Within the dimming window, perform dynamic dimming operations and suppress the triggering of overload protection;

[0078] S140. Within the detection window, perform a fault scan;

[0079] S150. Within the protection window, calculate the dynamic overload protection threshold according to the data of the dimming window and the detection window;

[0080] S160. According to the dynamic overload protection threshold, perform overload protection on the LED signal light group.

[0081] Among them, the LED signal light group refers to a traffic signal light device composed of multiple LED lamp beads, which is used to display traffic signals at positions such as road intersections. In this application, the LED signal light group needs to be dynamically controlled when the visibility decreases to ensure the visibility of the signal and the safety of the system.

[0082] Among them, the real-time working parameters refer to the current operating state data of the LED signal light group, such as current, voltage, temperature, etc. The acquisition of these parameters is crucial for subsequent dimming and protection operations, can reflect the real-time state of the system, and provide a basis for dynamic control.

[0083] Among them, the dimming period refers to the time period required to complete a full brightness adjustment. Dividing the dimming period into different functional windows can achieve time-division multiplexing of various functions, avoid mutual interference, and improve the stability and reliability of the system.

[0084] Among them, the dynamic dimming operation refers to adjusting the brightness of the LED signal light group in real time according to the current visibility and other environmental factors. This operation can optimize energy consumption while ensuring the visibility of the signal.

[0085] Among them, the dynamic overload protection threshold refers to the overload protection trigger value dynamically calculated according to the real-time working state. Compared with the fixed threshold, the dynamic threshold can better adapt to different working conditions, reduce false triggering, and ensure the necessary protection function at the same time.

[0086] The core innovation of this application lies in the proposal to divide the dimming cycle into a dimming window, a detection window, and a protection window, achieving effective isolation and coordination of the functions of dynamic dimming, fault detection, and overload protection. This method solves the problem of mutual interference among various functions in traditional control schemes and improves the reliability and stability of the system under low visibility conditions. At the same time, the concept of a dynamic overload protection threshold is introduced, enabling the system to flexibly adjust the protection strategy according to the real-time working state, ensuring the safe operation of the LED signal lamp group while avoiding unnecessary protection triggers.

[0087] The working principle of this application can be described in detail as follows:

[0088] First, the system continuously monitors the environmental visibility through sensors. When the detected visibility is lower than the preset threshold, a special control mode is triggered. In this mode, the real-time working parameters of the LED signal lamp group are first obtained, including but not limited to data such as current, voltage, and temperature. These data are collected in real time through built-in sensors and data acquisition modules.

[0089] Next, according to the obtained real-time working parameters, the dimming cycle is divided into three functional windows: a dimming window, a detection window, and a protection window. This division is dynamic and is adjusted in real time according to the current working state and environmental conditions. For example, in the case of extremely low visibility, the proportion of the dimming window may be increased to ensure sufficient brightness adjustment time. This division method allows the system to focus on different tasks at different time periods, effectively avoiding mutual interference between functions. By determining the division through real-time working parameters, the matching of the timing arrangement with the current working state is ensured, improving the system's adaptability to environmental changes.

[0090] Within the dimming window, the system performs dynamic dimming operations. This includes calculating the required brightness level according to the current visibility and achieving brightness changes by adjusting the LED drive current. At the same time, within this window, the system temporarily suppresses the triggering of overload protection to ensure the continuity and effectiveness of the dimming operation.

[0091] Within the detection window, the system performs a fault scan. This includes checking the working state of the LED lamp beads, the performance of the drive circuit, temperature changes, etc. Through this regular inspection, potential faults can be detected in a timely manner, improving the overall reliability.

[0092] Within the protection window, the dynamic overload protection threshold is calculated based on the data collected in the previous window. This calculation process takes into account factors such as the current working current, voltage, temperature, etc., as well as historical operation data. The calculated dynamic threshold can better adapt to the current working conditions, ensuring the necessary protection function while avoiding false triggers.

[0093] Finally, the system performs overload protection on the LED signal light group according to the calculated dynamic overload protection threshold. If it detects that the actual working parameters exceed this dynamic threshold, the system will take corresponding protection measures, such as reducing the drive current or activating the standby circuit.

[0094] As a specific embodiment, an LED traffic signal light group installed at a major urban intersection. The signal light group consists of multiple high-brightness LED lamp beads, with a normal operating current of 700 mA and a rated power of 100 W. The system is equipped with a visibility sensor, a current sensor, a voltage sensor, and a temperature sensor.

[0095] When the visibility sensor detects that the visibility has decreased to 30 meters (below the preset threshold of 50 meters), the system enters the special control mode. First, the system obtains the real-time working parameters: the current working current is 680 mA, the voltage is 24 V, and the temperature is 45 °C.

[0096] Based on these parameters, the system divides a 1-second dimming cycle into three windows: a 500-ms dimming window, a 300-ms detection window, and a 200-ms protection window.

[0097] Within the 500-ms dimming window, the system calculates that in order to ensure visibility, the brightness needs to be increased by 30%. Therefore, the drive current is gradually increased to 884 mA. During this process, the overload protection function is temporarily suppressed to ensure the smooth completion of the dimming operation.

[0098] Within the subsequent 300-ms detection window, the system performs a quick fault scan. The inspection results show that all LED lamp beads are working normally, the performance of the drive circuit is stable, and the temperature has risen to 48 °C, which is within the acceptable range.

[0099] Within the 200-ms protection window, the system calculates the dynamic overload protection threshold based on the collected data. Considering the current high-brightness working state and the rising temperature, the system dynamically adjusts the overload protection threshold from the original 1000 mA to 1100 mA.

[0100] Finally, the system performs overload protection according to this new dynamic threshold. Since the current working current (884 mA) is lower than the new protection threshold (1100 mA), the system continues to maintain its current working state while closely monitoring the changes in various parameters.

[0101] In this way, the LED signal light group can provide sufficient brightness under low visibility conditions while maintaining the stability and safety of the system. The dynamically adjusted overload protection threshold ensures that the system will not accidentally trigger the protection mechanism due to temporary high-power operation, thus ensuring the continuity and reliability of traffic signals.

[0102] In some of the above embodiments of the present application, a dimming period is divided into a dimming window, a detection window, and a protection window according to real-time operating parameters to control an LED signal lamp group when visibility decreases. However, in this process, there are still challenges in accurately dividing each functional window according to real-time operating parameters and determining appropriate timing allocation rules. Simple fixed timing division may not be able to adapt to complex and changeable actual working conditions, affecting the performance and reliability of the LED signal lamp group.

[0103] In response, the present application further proposes that the steps of dividing the dimming period into a dimming window, a detection window, and a protection window according to real-time operating parameters include: obtaining the current change rate and voltage fluctuation parameters of the LED signal lamp group; determining the timing allocation rules for each functional window based on the current change rate and voltage fluctuation parameters; and dividing the dimming period into mutually isolated dimming windows, detection windows, and protection windows according to the timing allocation rules.

[0104] This solution uses the obtained current change rate and voltage fluctuation parameters of the LED signal lamp group as the basis for dividing the functional windows. These two parameters can reflect the real-time operating state and potential risks of the LED signal lamp group. Determining the timing allocation rules based on these parameters can make the window division more flexible and accurate.

[0105] Specifically, the current change rate can be obtained by continuously sampling the current values of the LED signal lamp group and calculating the ratio of the current change amount between adjacent sampling points to the time interval. For example, the current change rate can be represented by the formula ΔI / Δt, where ΔI is the current change amount and Δt is the sampling time interval. The voltage fluctuation parameter can be characterized by calculating the standard deviation or peak value of the voltage over a certain period of time.

[0106] When determining the timing allocation rules based on the current change rate and voltage fluctuation parameters, various strategies can be adopted. For example, when the current change rate is large, it may mean that the LED signal lamp group is experiencing rapid brightness changes. At this time, the proportion of the dimming window can be increased to ensure the smoothness of the dimming operation. When the voltage fluctuation parameter is large, it may indicate unstable power supply or potential faults. At this time, the proportion of the detection window and the protection window can be appropriately increased to enhance the security of the system.

[0107] Furthermore, the timing allocation rules can adopt a dynamic weight algorithm. For example, thresholds for the current change rate and voltage fluctuation parameters can be set, and when the parameters exceed the thresholds, the weights of the corresponding windows are increased accordingly. The specific weight allocation can use the following formula:

[0108] W_dimming = α * (ΔI / Δt) / (ΔI / Δt + σV);

[0109] W_Detection = β * σV / (ΔI / Δt + σV);

[0110] W_Protection = 1 - W_Dimming - W_Detection;

[0111] Where, W represents the weight of each window, α and β are adjustable coefficients, and σV represents the standard deviation of the voltage.

[0112] According to the calculated weights, the dimming cycle can be divided into isolated dimming windows, detection windows, and protection windows. For example, if a dimming cycle is 100 ms, and the calculated weights are W_Dimming = 0.5, W_Detection = 0.3, and W_Protection = 0.2 respectively, then the dimming window can be set to the first 50 ms, the detection window to the middle 30 ms, and the protection window to the last 20 ms.

[0113] Through this dynamic adjustment mechanism, the technical solution of this application can flexibly allocate the timing of each functional window according to the real-time working state of the LED signal lamp group, effectively solving the problem that fixed timing division cannot adapt to complex working conditions. This method can maximize the visibility and reliability of the LED signal lamp group in case of reduced visibility while ensuring system safety.

[0114] As a preferred implementation, the dynamic division of the above functional windows can be implemented in a microcontroller. The microcontroller can collect the current and voltage data of the LED signal lamp group in real time through an analog-to-digital converter (ADC), and calculate the current change rate and voltage fluctuation parameters. Then, the microcontroller calculates the weights of each window according to a preset algorithm and controls the switching of each functional window through timer interrupts.

[0115] For example, assuming a microcontroller is used, a basic timer with a period of 100 μs can be set to sample the current and voltage. Each time an interrupt occurs, the conversion result of the ADC is read, and the current change rate and voltage fluctuation parameters are updated. The weights are calculated every 1000 interrupts (i.e., 100 ms), and the allocation of the functional windows is updated.

[0116] In specific implementation, three independent timers can be used to control the start and end of each functional window. When entering the dimming window, the PWM output is started to perform the dimming operation; when entering the detection window, the PWM output is paused and the fault scanning program is started; when entering the protection window, the overload protection calculation and threshold update are performed.

[0117] Through this implementation, the technical solution of this application can achieve precise timing control, ensure the isolation between each functional window, and avoid mutual interference. At the same time, due to the adoption of the dynamic allocation mechanism, the system can quickly respond to the changes in the working state of the LED signal lamp group, improving the overall control accuracy and reliability.

[0118] In some of the above embodiments of the present application, a timing allocation rule for determining each functional window based on the current change rate and voltage fluctuation parameters is proposed to optimize the control method of the LED signal light group. However, in this process, there are still challenges in how to dynamically adjust the allocation ratio of each functional window according to the changes of real-time electrical parameters, and how to balance the dimming demand and circuit protection demand under different working states. Especially under extreme weather conditions, the current and voltage may fluctuate violently at the same time, and how to quickly respond and make a reasonable window allocation decision has become an urgent problem to be solved.

[0119] In response to this, the present application further proposes to calculate the degree of deviation from a preset threshold based on the current change rate and voltage fluctuation parameters; determine the priority relationship between the dimming window and the detection window according to the degree of deviation from the preset threshold; when the current change rate exceeds the first critical value, preferentially extend the duration of the dimming window and shorten the duration of the detection window; when the voltage fluctuation parameter exceeds the second critical value, preferentially allocate the duration of the protection window and dynamically compress the proportion of the dimming window; generate a dynamic timing allocation rule based on the priority relationship.

[0120] The present application realizes the flexible allocation of each functional window by introducing a dynamic priority mechanism based on real-time electrical parameters. Specifically, first, calculate the degree of deviation of the current change rate and voltage fluctuation parameters from the preset threshold. This step can be achieved in various ways, such as using methods like percentage deviation, standard deviation, or adaptive threshold. The calculated degree of deviation directly reflects the current electrical state of the system and provides a quantitative basis for subsequent decisions.

[0121] According to the calculated degree of deviation, the present application determines the priority relationship between the dimming window and the detection window. This process can adopt methods such as a weighted scoring system or a fuzzy logic controller. For example, weight coefficients for the current change rate and voltage fluctuation parameters can be set, and a priority index is calculated comprehensively. When this index exceeds a certain threshold, the corresponding window adjustment strategy is triggered.

[0122] Furthermore, the present application introduces two key critical values: the first critical value is for the current change rate, and the second critical value is for the voltage fluctuation parameter. When the current change rate exceeds the first critical value, the system will preferentially extend the duration of the dimming window and shorten the duration of the detection window. The purpose of this strategy is to ensure sufficient time for precise dimming to maintain the stable output of the LED signal light group when the current changes violently. When specifically implemented, a dynamic proportional adjustment algorithm can be used to linearly or non-linearly increase the duration of the dimming window according to the exceeding degree of the current change rate.

[0123] Accordingly, when the voltage fluctuation parameter exceeds the second critical value, the system will preferentially allocate the protection window duration and dynamically compress the proportion of the dimming window. This mechanism aims to cope with possible voltage anomalies and ensure system safety by promptly initiating protection measures. The implementation method can include using a preset protection window duration increment table and selecting the corresponding increment value according to the degree of voltage fluctuation. At the same time, to maintain the overall balance of the system, the compression ratio of the dimming window can be inversely proportional to the increase ratio of the protection window.

[0124] Finally, based on the above priority relationship, this application generates a dynamic timing allocation rule. This rule is not static but continuously updated with the real-time changes of electrical parameters. The generated rule needs to consider the continuity and stability of the system and avoid frequent window switching from interfering with the normal operation of the LED signal light group.

[0125] The technical solution of this application realizes the dynamic optimization of the LED signal light group control system by real-time monitoring and analyzing the current change rate and voltage fluctuation parameters. This method can flexibly allocate resources under different working conditions, effectively balancing the dimming demand and circuit protection demand. Especially under extreme weather conditions, when the current and voltage fluctuate violently at the same time, the solution of this application can quickly respond and make reasonable window allocation decisions.

[0126] In some of the above embodiments of this application, a timing allocation rule for each functional window is proposed based on the current change rate and voltage fluctuation parameters to reasonably allocate the dimming, detection, and protection windows when the visibility decreases. However, in this process, when the current change rate and voltage fluctuation parameter exceed their respective critical values at the same time, a conflict may occur between the dimming demand and the protection demand. In this case, simply allocating the window duration according to the preset rule may not meet the actual needs of the system, neither ensuring sufficient dimming time to improve the visibility of the signal light nor being able to promptly initiate the protection mechanism to ensure system safety.

[0127] In response to this, this application further proposes that when the current change rate and voltage fluctuation parameter exceed their respective critical values at the same time, calculate the dimming urgency index reflecting the degree of visibility decrease and the protection urgency index reflecting the circuit safety risk; compare the dimming urgency index with the protection urgency index and dynamically adjust the window allocation according to the comparison result: when the dimming urgency index is higher, preferentially extend the dimming window and compress the protection window; when the protection urgency index is higher, suspend the current dimming operation and immediately initiate the protection window; when both the current change rate and voltage fluctuation parameter do not exceed the critical value, allocate the duration of each window according to the preset ratio while ensuring that the detection window duration is not less than the safety threshold.

[0128] This application introduces a dimming urgency index and a protection urgency index, which respectively reflect the degree of visibility decrease and the circuit safety risk. By calculating and comparing these two indexes, the system can make more intelligent and flexible decisions in complex situations.

[0129] Specifically, the dimming urgency index can be calculated in various ways. For example, it can be calculated based on the difference between the current visibility and the preset safe visibility threshold, combined with the ratio of the current brightness of the LED signal light group to the maximum adjustable brightness. The calculation formula can be expressed as:

[0130] Dimming urgency index = α1 * (1 - current visibility / safe visibility threshold) + β1 * (1 - current brightness / maximum adjustable brightness);

[0131] Among them, α1 and β1 are weight coefficients that can be adjusted according to the actual application scenario.

[0132] The protection urgency index can be calculated based on the current change rate, voltage fluctuation parameters, and historical fault data. The calculation formula can be expressed as:

[0133] Protection urgency index = γ1 * (current change rate / current critical value) + δ * (voltage fluctuation parameter / voltage critical value) + ε * historical fault frequency;

[0134] Among them, γ1, δ, and ε are weight coefficients that can be adjusted according to the system characteristics. The historical fault frequency can be obtained by counting the number of faults within a certain time window.

[0135] By comparing these two indexes, the system can make more reasonable decisions. When the dimming urgency index is higher, the dimming window is preferentially extended and the protection window is compressed, which ensures that the LED signal light group can increase its brightness in time in case of a sharp decrease in visibility and guarantees traffic safety. For example, the dimming window can be extended to 1.5 times the original, while the protection window is compressed to 0.8 times the original.

[0136] When the protection urgency index is higher, the system will immediately suspend the dimming operation and start the protection window. This fast response mechanism can effectively prevent circuit overload or other potential safety risks. In this case, the protection window can be extended to 2 times the original, and the dimming operation is suspended for a complete cycle.

[0137] Under normal circumstances, that is, when both the current change rate and the voltage fluctuation parameter do not exceed the critical value, the system will allocate the duration of each window according to a preset ratio, while ensuring that the duration of the detection window is not lower than the safety threshold. For example, the duration ratio of the dimming window, the detection window, and the protection window can be set to 6:2:2, and ensure that the duration of the detection window is not lower than 10 ms.

[0138] This dynamic adjustment mechanism can find the best balance point between the visibility reduction and the circuit safety risk, which not only ensures the visibility of the LED signal lamp group but also ensures the safe and stable operation of the system. By calculating and comparing the dimming urgency index and the protection urgency index in real time, the system can flexibly adjust the allocation of each function window according to the actual situation, so as to better cope with complex environmental changes.

[0139] In some of the above embodiments of the present application, a dynamic overload protection threshold is calculated based on the data of the dimming window and the detection window to perform overload protection on the LED signal lamp group. However, in this process, the prior art lacks a method for dynamically adjusting the overload protection threshold according to real-time working parameters and environmental conditions. Especially in the case of reduced visibility, a fixed overload protection threshold may not meet the dynamic dimming requirements of the LED signal lamp group and cannot effectively cope with the circuit safety risks under different working modes.

[0140] In response to this, the present application further proposes that the steps of calculating the dynamic overload protection threshold according to the data of the dimming window and the detection window include: obtaining the current data I(t) and voltage data V(t) within the dimming window, and the fault feature data F(t) within the detection window; obtaining the current visibility Vis, historical fault data H(t), and preset safety parameter S; setting the basic protection threshold Pbase, emergency threshold Visemerg, emergency mode coefficient β, normal mode coefficient γ, and historical fault influence attenuation coefficient λ; when the current visibility Vis is less than the emergency threshold Visemerg, enter the emergency mode and perform the following steps: calculate the current change rate ΔI(t) = (I(t) - Iavg) / Iavg, where Iavg is the historical average current; calculate the voltage change rate ΔV(t) = (V(t) - Vavg) / Vavg, where Vavg is the historical average voltage; calculate the dynamic correction coefficient: α(t) = 1 + β*(ΔI(t) + ΔV(t) - F(t) - (1 - Vis / Visemerg))*exp(-λH(t)); calculate the dynamic overload protection threshold Pth(t) = Pbase*α(t)*S in the emergency mode; when the current visibility Vis is greater than or equal to the emergency threshold Visemerg, enter the normal mode and perform the following steps: calculate the current change rate ΔI(t) = (I(t) - Iavg) / Iavg; calculate the dynamic overload protection threshold Pth(t) = Pbase*(1 + γ*ΔI(t)) in the normal mode; apply the calculated dynamic overload protection threshold Pth(t) to the overload protection of the LED signal light group.

[0141] Among them, the fault feature data F(t) refers to the quantitative data obtained by performing a fault scan within the detection window, and is used to characterize the current fault state or potential fault risk of the LED signal light group. This is a real-time collected parameter that reflects the fault characteristics of the system at the current moment t. It is a numerical index obtained by comprehensively examining factors such as the working state of the LED lamp beads, the performance of the drive circuit, and temperature changes. The larger the value, the more obvious the current fault characteristics of the system or the higher the fault risk.

[0142] The historical fault data H(t) refers to the statistical value of the cumulative fault conditions of the system in the past period of time, and is used to characterize the fault frequency or severity in the historical operation of the LED signal light group. This is a cumulative parameter that is updated over time and reflects the comprehensive situation of the system's historical faults. In the calculation of the dynamic overload protection threshold, it is used in combination with the historical fault influence attenuation coefficient λ to form the term exp(-λH(t)), so that the system with more historical faults is more cautious when adjusting the dynamic overload protection threshold.

[0143] The technical solution of the present application effectively solves the problem that fixed thresholds cannot adapt to different working conditions by dynamically adjusting the overload protection threshold. In the case of reduced visibility, this method can effectively prevent the occurrence of overload while ensuring the normal operation of the signal light group. Specifically, when visibility decreases, the system will enter emergency mode, and the calculation of the dynamic overload protection threshold will consider more factors, including the rate of change of current and voltage, fault characteristics, visibility changes, and historical fault data. This comprehensive consideration enables the system to more accurately control the overload protection of the LED signal light group under low visibility conditions.

[0144] For example, when visibility suddenly drops to 30 meters, the system will immediately switch to emergency mode. In this case, the LED signal light group needs to increase the brightness to ensure visibility, which may cause significant changes in current and voltage. By dynamically calculating the correction factor α(t), the system is able to appropriately increase the overload protection threshold according to these changes, allowing the LED signal light group to operate at a higher power for a short period of time without triggering unnecessary protection actions. At the same time, because the fault characteristic data F(t) and historical fault data H(t) are taken into account in the calculation, the system can still maintain sensitivity to potential faults, ensuring that the safety of the equipment is not compromised while increasing the brightness.

[0145] When visibility returns to normal levels (such as 100 meters), the system automatically switches back to normal mode. In this mode, the calculation of the overload protection threshold is mainly based on the current change rate. This simplified calculation method can provide adequate protection under normal working conditions, while reducing unnecessary calculation complexity, which is conducive to the long-term stable operation of the system.

[0146] Through this dynamic adjustment mechanism, the technical solution of the present application can maintain the reliability and safety of the LED signal light group under various environmental conditions. In particular, under severe weather conditions, the method can effectively prevent the occurrence of overload while ensuring the normal operation of the signal light group, thereby improving the overall reliability of the traffic signal system.

[0147] As a preferred implementation, assume that the LED signal light group in a city traffic signal light system is configured as follows:

[0148] Basic protection threshold Pbase = 100W;

[0149] Emergency threshold Visemerg = 50m;

[0150] The emergency mode coefficient β = 0.2;

[0151] Normal mode coefficient γ = 0.1;

[0152] The attenuation coefficient of historical fault impact λ = 0.05;

[0153] The preset safety parameter S = 1.1;

[0154] On a rainy day, the visibility gradually decreases. When the visibility drops to 45 meters, the system enters the emergency mode. At this time, the system obtains the following data:

[0155] The current current I(t) = 2.2A, and the historical average current Iavg = 2.0A;

[0156] The current voltage V(t) = 48V, and the historical average voltage Vavg = 45V;

[0157] The fault characteristic data F(t) = 0.02;

[0158] The current visibility Vis = 45m;

[0159] The historical fault data H(t) = 0.1;

[0160] Execute the following calculation steps:

[0161] Calculate the current change rate: ΔI(t) = (2.2 - 2.0) / 2.0 = 0.1;

[0162] Calculate the voltage change rate: ΔV(t) = (48 - 45) / 45 ≈ 0.067;

[0163] Calculate the dynamic correction coefficient:

[0164] α(t) = 1 + 0.2 * (0.1 + 0.067 - 0.02 - (1 - 45 / 50)) * exp(-0.05 * 0.1)

[0165] ≈ 1.0296;

[0166] Calculate the dynamic overload protection threshold in the emergency mode:

[0167] Pth(t) = 100 * 1.0296 * 1.1 ≈ 113.256W.

[0168] Through this dynamic adjustment, the system increases the overload protection threshold from the original 110W (100W * 1.1) to approximately 113.256W. This small but important adjustment allows the LED signal light group to operate at a slightly higher power under low visibility conditions to increase brightness and visibility, while still maintaining effective protection for the device.

[0169] In some of the above embodiments of the present application, an overload protection of the LED signal lamp group is performed according to a dynamic overload protection threshold to meet the LED control requirements in case of reduced visibility. However, in this process, there are still challenges in how to flexibly adjust the protection measures according to the changes of the real-time working current and visibility parameters, and how to continuously monitor the system state during the protection process and achieve a smooth recovery. Simply implementing a fixed overload protection strategy may not be able to adapt to complex and changeable environmental conditions, and it is also difficult to balance the protection of system safety and the maintenance of the signal lamp function.

[0170] In response to this, the present application further proposes that the steps of performing the overload protection of the LED signal lamp group according to the dynamic overload protection threshold include: when the real-time working current exceeds the dynamic overload protection threshold, determining an overload response coefficient according to the deviation degree between the current visibility parameter and the threshold; based on the overload response coefficient and the exceeding amplitude of the real-time working current, selecting and executing corresponding dynamic protection measures, and the dynamic protection measures include at least one of current regulation, circuit switching, and load optimization operations; when implementing the dynamic protection measures, synchronously monitoring the change trend of visibility; when the real-time working current drops back to the dynamic overload protection threshold and the visibility parameter returns to the safe range, gradually restoring the working state of the LED signal lamp group according to a preset recovery curve.

[0171] The present application introduces an overload response coefficient to achieve dynamic adjustment of the protection measures. The overload response coefficient can be calculated in various ways. For example, a linear mapping method can be used to map the deviation degree between the visibility parameter and the threshold to the range of 0-1.

[0172] When selecting and executing dynamic protection measures based on the overload response coefficient and the current exceeding amplitude, multiple threshold intervals can be set. For example, when the overload response coefficient is between 0-0.3, current regulation is mainly performed; when it is between 0.3-0.7, circuit switching is performed; when it is above 0.7, load optimization operations are performed. This hierarchical response mechanism ensures the pertinence and flexibility of the protection measures. For example, using a two-dimensional matrix, with the horizontal axis being the overload response coefficient and the vertical axis being the current exceeding amplitude, each unit in the matrix corresponds to a protection measure. When the overload response coefficient is between 0-0.3 and the current exceeding amplitude <5%, the mildest current regulation is performed; when the overload response coefficient is between 0-0.3 but the current exceeding amplitude is between 5%-15%, stricter current regulation is performed; when the overload response coefficient is between 0.3-0.7 or the current exceeding amplitude is between 15%-25%, circuit switching is performed; when the overload response coefficient >0.7 or the current exceeding amplitude >25%, load optimization operations are performed.

[0173] While implementing the protection measures, this application introduces a real-time monitoring mechanism for the visibility change trend. The short-term trend can be calculated using the sliding window method, or time series analysis methods such as exponential smoothing can be used to predict future changes. This continuous monitoring ensures that the system can respond promptly to environmental changes, avoiding overprotection or underprotection situations.

[0174] Finally, this application designs a progressive recovery mechanism based on a preset recovery curve. The recovery curve can be linear or non-linear, such as an S-shaped curve, to adapt to different recovery requirements. This gentle recovery process helps to avoid sudden changes when the LED signal light group returns to the normal working state, improving the stability and reliability of the system.

[0175] Through the above technical means, this application effectively solves the flexibility and adaptability problems of the overload protection of the LED signal light group under changing visibility conditions. It can not only dynamically adjust the protection strategy according to the real-time situation, but also continuously monitor the system status during the protection process and achieve a smooth recovery. This method not only ensures system safety but also maximally maintains the normal function of the signal lights, providing an efficient and reliable solution for the control of LED signal lights in complex and changeable environments.

[0176] This application realizes the dynamic adjustment of the protection measures by introducing an overload response coefficient. The overload response coefficient takes into account the deviation degree between the current visibility and the threshold, enabling the protection measures to be precisely adjusted according to the actual environmental conditions. Specifically, the overload response coefficient can be calculated in the following way:

[0177] First, define the visibility deviation δ = (Vis_threshold - Vis_current) / Vis_threshold, where Vis_threshold is the visibility threshold and Vis_current is the current visibility.

[0178] Then, a non-linear mapping function can be used to calculate the overload response coefficient α:

[0179] α = 1 / (1 + e^(-k * δ));

[0180] Where k is an adjustment coefficient used to control the steepness of the response curve. This S-shaped curve mapping can provide a small response when the visibility is close to the threshold, and quickly increase the response intensity when the visibility is significantly reduced.

[0181] Based on the overload response coefficient α and the excess amplitude ΔI of the real-time working current, this application selects and executes the corresponding dynamic protection measures. For example, the following rules can be set:

[0182] When α < 0.3 and ΔI < 10%, perform mild current regulation, such as reducing the operating current by 5%.

[0183] When 0.3 ≤ α < 0.7 or 10% ≤ ΔI < 20%, perform circuit switching, such as activating a standby circuit or reallocating the load.

[0184] When α ≥ 0.7 or ΔI ≥ 20%, perform load optimization operations, such as turning off some non-critical LED light groups.

[0185] When implementing dynamic protection measures, this application synchronously monitors the visibility change trend. The exponential weighted moving average (EWMA) method can be used to calculate these trends:

[0186] EWMA(t) = λ1 * Value(t) + (1 - λ) * EWMA(t-1);

[0187] where λ is the smoothing factor (0 < λ1 < 1), and Value(t) is the measured value at the current moment. This method can effectively filter short-term fluctuations while maintaining sensitivity to long-term trends.

[0188] When the real-time operating current drops back to the dynamic overload protection threshold and the visibility parameter returns to the safe range, this application gradually restores the operating state of the LED signal light group according to the preset recovery curve. The following S-shaped recovery curve can be adopted:

[0189] I(t) = Imax / (1 + e^(-r * (t - t0)));

[0190] where Imax is the target operating current, r is the recovery rate parameter, and t0 is the recovery midpoint time. This curve can provide a slower change rate at the beginning and end of the recovery, and quickly approach the target value in the middle, thus achieving a smooth transition.

[0191] Through the synergistic effect of these technical means, this application can not only flexibly adjust the protection strategy according to the visibility change, but also continuously optimize the system state during the protection process and achieve a smooth recovery. This method maximally maintains the normal function of the signal lights while ensuring system safety, providing an efficient and reliable solution for the control of LED signal lights in complex and changeable environments.

[0192] As a preferred implementation, this application can be implemented in a traffic signal control system as follows:

[0193] First, the system is equipped with a high-precision visibility sensor that can measure the environmental visibility in real time with an accuracy of ±1 meter. At the same time, a current detection module is integrated into the drive circuit of the LED signal light group, with a sampling frequency of 1 kHz, which can accurately capture current fluctuations.

[0194] The system sets the initial visibility threshold Vis_threshold to 100 meters. When the detected visibility is lower than this value, the dynamic overload protection mechanism is activated. Suppose the current measured visibility Vis_current is 80 meters at a certain moment, then the calculated visibility deviation δ = (100 - 80) / 100 = 0.2.

[0195] Use the aforementioned S-shaped curve mapping function to calculate the overload response coefficient α, and set k = 10:

[0196] α = 1 / (1 + e^(-10 * 0.2)) ≈ 0.62;

[0197] At the same time, assume that the detected real-time working current is 2.2A, while the dynamic overload protection threshold is 2A, then the excess amplitude ΔI = (2.2 - 2) / 2 = 10%.

[0198] Based on the values of α and ΔI, the system selects to perform a circuit switching operation. Specifically, activate the standby LED drive circuit and transfer part of the load to this circuit to disperse the power burden.

[0199] While implementing the protection measures, the system uses the EWMA method to monitor the changing trends of visibility and current, and sets λ = 0.1:

[0200] EWMA_vis(t) = 0.1 * 80 + 0.9 * EWMA_vis(t - 1);

[0201] EWMA_current(t) = 0.1 * 2.2 + 0.9 * EWMA_current(t - 1);

[0202] The system updates the EWMA value once per second and continuously monitors the trend changes.

[0203] When it is detected that the real-time working current drops below 2A and the visibility rises back to 95 meters, the system starts the recovery program. Adopt an S-shaped recovery curve, set Imax = 2A, r = 0.5, t0 = 10s:

[0204] I(t) = 2 / (1 + e^(-0.5 * (t - 10)));

[0205] The system smoothly restores the normal working state of the LED signal light group according to this curve within 20 seconds, ensuring the continuity and stability of traffic signals.

[0206] Through this implementation manner, the present application can accurately control the working state of the LED signal light group under harsh weather conditions, effectively prevent the occurrence of overload situations, and at the same time ensure the visibility and functionality of the signal lights. This not only improves the reliability of the traffic signal system but also provides a safer traffic environment for road users.

[0207] In some of the above embodiments of the present application, an extended dimming window is proposed to optimize the dimming effect of the LED signal light group when the visibility decreases. However, during this process, it may lead to insufficient protection window time, affecting the safety and stability of the system. Specifically, when the dimming window is overly extended, it may squeeze the time of the protection window, causing the system to be unable to execute necessary protection measures in a timely manner, thus increasing the risk of overload or failure of the LED signal light group.

[0208] In response to this, the present application further proposes to monitor the remaining time of the protection window in real time during the process of extending the dimming window; when it is detected that the remaining time of the protection window is lower than a preset minimum protection threshold, start window compensation control: obtain the current visibility decrease rate and circuit temperature parameters; calculate the maximum allowable extension amplitude of the dimming window based on the composite relationship between the visibility decrease rate and the temperature parameters; in the next dimming cycle, re - allocate the duration of each functional window according to the maximum allowable extension amplitude of the dimming window; when the protection window time in three consecutive dimming cycles is lower than the minimum protection threshold, forcibly insert an independent protection period.

[0209] The technical solution proposed by the present application effectively solves the problem of insufficient protection window time caused by overly extended dimming windows by monitoring the remaining time of the protection window in real time and starting window compensation control when the remaining time is lower than the preset minimum protection threshold. Monitoring the remaining time of the protection window in real time can be achieved by setting a timer or a counter, and when the remaining time is lower than the preset minimum protection threshold, the window compensation control mechanism is triggered.

[0210] The window compensation control mechanism first obtains the current visibility decrease rate and circuit temperature parameters. The visibility decrease rate can be obtained by continuously sampling the data of the ambient light sensor and calculating its change rate. The circuit temperature parameter can directly measure the temperature of the LED driving circuit through a temperature sensor. These two parameters reflect the current environmental conditions and the working state of the LED signal light group, providing a basis for calculating the maximum allowable extension amplitude of the dimming window.

[0211] Based on the composite relationship between the visibility decrease rate and the temperature parameter, calculate the maximum allowable extension amplitude of the dimming window. This step can adopt a preset algorithm or a look-up table method. For example, a basic extension amplitude can be set and then adjusted according to the visibility decrease rate and the temperature parameter. Specifically, when the visibility decrease rate is high, the extension amplitude can be appropriately increased to ensure sufficient dimming effect; when the temperature parameter is high, the extension amplitude needs to be restricted to prevent system overheating.

[0212] In the next dimming cycle, reallocate the duration of each functional window according to the calculated maximum extension amplitude of the dimming window. This step can be achieved by dynamically adjusting the time ratios of the dimming window, the detection window, and the protection window. For example, if the maximum extension amplitude of the dimming window is 20% of the original dimming window, the time of the dimming window can be increased by 20%, and the times of the detection window and the protection window can be shortened proportionally, but it is necessary to ensure that the time of the protection window is not lower than the minimum protection threshold.

[0213] When the protection window time in three consecutive dimming cycles is lower than the minimum protection threshold due to factors such as rapid deterioration of environmental conditions, system response delay, sudden change of system state, inaccurate sensor data, etc., this application proposes to forcibly insert an independent protection period. This can be achieved by inserting a dedicated protection period in the dimming cycle, which is specifically used to execute necessary protection measures and is not affected by other functional windows. For example, a complete dimming cycle can be temporarily converted into a protection period, or an additional protection period can be inserted between multiple dimming cycles.

[0214] Through the above technical solutions, this application realizes the dynamic balance between the dimming demand and the protection demand. In the case of decreasing visibility, the system can extend the dimming window according to the actual situation to improve the visibility of the LED signal light group. At the same time, through real-time monitoring and dynamic adjustment, it is ensured that the protection window has sufficient time to execute necessary protection measures, thereby maintaining the safety and stability of the system.

[0215] As a preferred implementation manner, this application can be implemented in an LED traffic signal control system. The system includes an LED signal light group, a controller, an ambient light sensor, and a temperature sensor. The controller can be an embedded system based on a microprocessor or an FPGA, running the control algorithm of this application.

[0216] In practical applications, when the ambient light sensor detects that the visibility is lower than the preset threshold, the system enters the low visibility mode. The controller starts to perform dynamic dimming operations and simultaneously starts monitoring the remaining time of the protection window. Assume that under normal circumstances, the time ratios of the dimming window, the detection window, and the protection window are 6:2:2, and each dimming cycle is 100 ms.

[0217] When the system detects that the remaining time of the protection window is lower than a preset minimum protection threshold (e.g., 15 ms), window compensation control is triggered. The controller reads the data of the ambient light sensor, calculates the visibility degradation rate, and simultaneously obtains the data of the temperature sensor. Assume that the current visibility degradation rate is 5% / min and the circuit temperature is 60 °C.

[0218] Based on these parameters, the controller calculates that the maximum allowable dimming window extension amplitude is 15%. In the next dimming cycle, the controller increases the dimming window time from 60 ms to 69 ms, while reducing the detection window time to 16 ms, and the protection window time remains at 15 ms (not lower than the minimum protection threshold). The new time allocation becomes 69:16:15, and the sum is still 100 ms.

[0219] Although the system has tried to maintain the protection window not lower than the minimum threshold, as the environmental conditions continue to deteriorate, the protection window time may be further compressed in subsequent dimming cycles. If the system detects that the protection window time for three consecutive dimming cycles (i.e., 300 ms) is lower than 15 ms, the controller will forcibly insert an independent protection period of 50 ms. During these 50 ms, the system pauses the dimming operation and focuses on performing protection measures, such as checking the circuit temperature, current monitoring, etc.

[0220] In this way, while ensuring the dimming effect of the LED signal light group, this application effectively avoids the safety risks caused by insufficient protection window time. The system can dynamically adjust the time allocation of the functional windows according to the actual environment and working conditions, achieving a balance between improving the visibility of the signal lights and maintaining the system security, thereby improving the overall performance and reliability of the traffic signal light system under adverse weather conditions. In the second aspect, referring to Figure 2 , this application also proposes an LED control device for controlling an LED signal light group in the case of decreasing visibility. The device includes:

[0221] A parameter acquisition module 210, configured to acquire the real-time working parameters of the LED signal light group when the visibility is lower than the threshold;

[0222] A timing division module 220, configured to divide the dimming cycle into a dimming window, a detection window, and a protection window according to the real-time working parameters;

[0223] A dimming control module 230, configured to perform dynamic dimming operations and suppress the triggering of overload protection within the dimming window;

[0224] A fault detection module 240, configured to perform fault scanning within the detection window;

[0225] A threshold calculation module 250, configured to calculate a dynamic overload protection threshold according to the data of the dimming window and the detection window within the protection window;

[0226] A protection execution module 260 is configured to perform overload protection on the LED signal light group according to a dynamic overload protection threshold.

[0227] By dynamically adjusting the dimming, detection, and protection mechanisms of the LED signal light group when visibility decreases, the conflict problem between the brightness increase of the LED light group and the misoperation of overload protection in the prior art under special weather conditions is solved. It can avoid the misoperation of overload protection caused by brightness increase under special weather conditions, achieve dynamic dimming and precise fault isolation, and at the same time keep the system power consumption stable.

[0228] In a third aspect, the present application further provides an electronic device, including a processor and a memory. The memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the above method are run.

[0229] Through the above technical solution, the processor and the memory are interconnected and communicate with each other through a communication bus and / or other forms of connection mechanisms (not marked). The memory stores computer-readable instructions executable by the processor. When the electronic device runs, the processor executes the computer-readable instructions to execute the method in any optional implementation manner of the above embodiments to achieve the following functions: when the visibility is lower than the threshold, obtain the real-time working parameters of the LED signal light group; divide the dimming cycle into a dimming window, a detection window, and a protection window according to the real-time working parameters; perform dynamic dimming operations and suppress the triggering of overload protection within the dimming window; perform fault scanning within the detection window; calculate the dynamic overload protection threshold according to the data of the dimming window and the detection window within the protection window; perform overload protection on the LED signal light group according to the dynamic overload protection threshold.

[0230] In a fourth aspect, the present application further provides a storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above method are run.

[0231] Through the above technical solution, when the computer program is executed by the processor, the method in any optional implementation manner of the above embodiments is executed to achieve the following functions: when the visibility is lower than the threshold, obtain the real-time working parameters of the LED signal light group; divide the dimming cycle into a dimming window, a detection window, and a protection window according to the real-time working parameters; perform dynamic dimming operations and suppress the triggering of overload protection within the dimming window; perform fault scanning within the detection window; calculate the dynamic overload protection threshold according to the data of the dimming window and the detection window within the protection window; perform overload protection on the LED signal light group according to the dynamic overload protection threshold.

[0232] Among them, the computer-readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM for short), electrically erasable programmable read-only memory (EEPROM for short), erasable programmable read-only memory (EPROM for short), programmable read-only memory (PROM for short), read-only memory (ROM for short), magnetic memory, flash memory, magnetic disk or optical disk.

[0233] In the embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division, and there can be other division methods in actual implementation. For another example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed mutual coupling or direct coupling or communication connection can be through some communication interfaces. The indirect coupling or communication connection of the devices or units can be electrical, mechanical or other forms.

[0234] In addition, the units described as separate components may or may not be physically separated, and the components displayed as units may or may not be physical units. They can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0235] Furthermore, in each embodiment of the present application, the various functional modules can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0236] The above are only the embodiments of the present application and are not used to limit the protection scope of the present application. For those skilled in the art, the present application can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A LED control method for controlling an LED signal light assembly in the case of reduced visibility, characterized in that: The method includes: When visibility is lower than the threshold, the real-time working parameters of the LED signal light group are obtained; According to the real-time working parameters, the dimming cycle is divided into a dimming window, a detection window and a protection window; In the dimming window, a dynamic dimming operation is performed and overload protection triggering is suppressed; Performing fault scanning within the detection window; In the protection window, a dynamic overload protection threshold is calculated according to data of the dimming window and the detection window; The overload protection of the LED signal light group is performed according to the dynamic overload protection threshold.

2. The LED control method according to claim 1, characterized in that: The step of dividing the dimming cycle into a dimming window, a detection window and a protection window according to the real-time working parameters comprises: Obtaining the current change rate and voltage fluctuation parameters of the LED signal light group; Determining a timing allocation rule for each functional window based on the current change rate and voltage fluctuation parameters; According to the timing allocation rule, the dimming cycle is divided into a dimming window, a detection window and a protection window which are isolated from each other.

3. The LED control method according to claim 2, characterized in that: The step of determining the timing allocation rules of each functional window based on the current change rate and the voltage fluctuation parameter comprises: Calculating the degree of deviation from a preset threshold value based on the acquired current change rate and voltage fluctuation parameters; Determining the priority relationship between the dimming window and the detection window according to the degree of deviation from the preset threshold; When the current change rate exceeds the first critical value, the dimming window duration is preferentially extended and the detection window duration is shortened; When the voltage fluctuation parameter exceeds the second critical value, the protection window duration is allocated preferentially and the dimming window ratio is dynamically compressed; A dynamic timing allocation rule is generated based on the priority relationship.

4. The LED control method according to claim 3, characterized in that: The method also includes the steps of: When the current change rate and the voltage fluctuation parameter simultaneously exceed their respective critical values, a dimming urgency index reflecting the degree of visibility reduction and a protection urgency index reflecting the circuit safety risk are calculated; Compare the dimming urgency index with the protection urgency index, and dynamically adjust the window allocation according to the comparison result: When the dimming urgency index is higher, priority is given to extending the dimming window and compressing the protection window; When the protection urgency index is higher, the current dimming operation is suspended and the protection window is started immediately; When the current change rate and the voltage fluctuation parameters do not exceed the critical value, the duration of each window is allocated according to a preset ratio, while ensuring that the duration of the detection window is not less than the safety threshold.

5. The LED control method according to claim 1, characterized in that: The step of calculating the dynamic overload protection threshold according to the data of the dimming window and the detection window comprises: Acquire current data I(t), voltage data V(t) within the dimming window, and fault characteristic data F(t) within the detection window; Obtain current visibility Vis, historical fault data H(t) and preset safety parameters S; Set the basic protection threshold Pbase, emergency threshold Visemerg, emergency mode coefficient β, normal mode coefficient γ and historical fault impact attenuation coefficient λ; When the current visibility Vis is less than the emergency threshold Visemerg, the emergency mode is entered and the following steps are performed: Calculate the current change rate ΔI(t)=(I(t)-Iavg) / Iavg, where Iavg is the historical average current; Calculate the voltage change rate ΔV(t)=(V(t)-Vavg) / Vavg, where Vavg is the historical average voltage; Calculate the dynamic correction factor: α(t)=1+β*(ΔI(t)+ΔV(t)-F(t)-(1-Vis / Visemerg))*exp(-λH(t)); Calculate the dynamic overload protection threshold Pth(t)=Pbase*α(t)*S in emergency mode; When the current visibility Vis is greater than or equal to the emergency threshold Visemerg, the system enters the normal mode and performs the following steps: Calculate the current change rate ΔI(t)=(I(t)-Iavg) / Iavg; Calculate the dynamic overload protection threshold Pth(t)=Pbase*(1+γ*ΔI(t)) in normal mode; The calculated dynamic overload protection threshold value Pth(t) is applied to the overload protection of the LED signal light group.

6. The LED control method according to claim 1, characterized in that: The step of performing overload protection of the LED signal light group according to the dynamic overload protection threshold comprises: When the real-time working current exceeds the dynamic overload protection threshold, the overload response coefficient is determined according to the degree of deviation between the current visibility parameter and the threshold; Based on the overload response coefficient and the excess amplitude of the real-time working current, select and execute a corresponding dynamic protection measure, wherein the dynamic protection measure includes at least one of current regulation, circuit switching and load optimization operation; When implementing the dynamic protection measures, the visibility change trend is monitored simultaneously; When the real-time working current drops back to the dynamic overload protection threshold and the visibility parameters recover to a safe range, the working state of the LED signal light group is gradually restored according to the preset recovery curve.

7. The LED control method according to claim 4, characterized in that: The method also includes the steps of: Real-time monitoring of the remaining time of the protection window during the process of extending the dimming window; When it is detected that the remaining time of the protection window is lower than the preset minimum protection threshold, the window compensation control is started: Obtain current visibility decrease rate and circuit temperature parameters; Based on the composite relationship between visibility decrease rate and temperature parameters, the maximum allowable dimming window extension is calculated; In the next dimming cycle, reallocate the duration of each functional window according to the maximum dimming window extension amplitude; When the protection window time of three consecutive dimming cycles is lower than the minimum protection threshold, an independent protection period is forcibly inserted.

8. An LED control device for controlling an LED signal light assembly in the case of reduced visibility, characterized in that: The device includes: A parameter acquisition module, used to obtain the real-time working parameters of the LED signal light group when the visibility is lower than the threshold; A timing division module, used to divide the dimming cycle into a dimming window, a detection window and a protection window according to the real-time working parameters; A dimming control module, used to perform dynamic dimming operations and suppress overload protection triggering within the dimming window; A fault detection module, used to perform fault scanning within the detection window; A threshold calculation module, used to calculate a dynamic overload protection threshold within the protection window according to data of the dimming window and the detection window; The protection execution module is used to execute overload protection of the LED signal light group according to the dynamic overload protection threshold.

9. An electronic device, characterized in that: The method comprises a processor and a memory, wherein the memory stores computer-readable instructions. When the computer-readable instructions are executed by the processor, the steps in the method according to any one of claims 1 to 7 are executed.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 7 are executed.

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