Light color shift control method and system

Abstract

The invention relates to the technical field of intelligent lighting control, and discloses a light color shift control method and system, and the method comprises the following steps: S1, receiving target color data and shift parameters through a user interaction interface; s2, acquiring an environment color temperature Tamb by using an environment light sensor, and monitoring an LED module junction temperature Tled through a PT1000 type temperature sensor; s3, calculating a color compensation parameter based on the offset parameter in the step S1 and the sensor data in the step S2; and S4, generating a PWM driving signal through an improved HSV-RGB bidirectional conversion model. By receiving the target color data and the offset parameters and collecting the environmental color temperature and the LED module junction temperature data, basic input and real-time state information are provided for color compensation calculation, so that the system can dynamically adjust the color parameters in combination with user requirements and environmental equipment states, and the pertinence and environmental adaptability of color control are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of intelligent lighting control, and in particular to a method and system for controlling light color shift. Background Art

[0002] In today's lighting applications, whether it's interior decorative ambient lighting, traffic lights, or professional stage lighting, precise control of light color is crucial. With technological advancements, multicolor lighting systems, such as RGB ambient lighting, have gained widespread adoption. These systems can produce rich colors and achieve diverse functions by blending different LED colors. However, factors such as the structural design of the lamp, environmental changes, and lamp aging can affect the light mixing effect, leading to a shift in light color, a phenomenon known as chromaticity drift. Currently, common solutions to this light color shift include optimizing the optical structure, adjusting materials, adding temperature compensation modules, and manually adjusting LED parameters.

[0003] Traditional lighting control can often only achieve fixed color output or simple static color adjustment, and lacks support for users' diverse dynamic color needs. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a method and system for controlling light color offset, which solves the problem that only fixed color output or simple static color adjustment can be achieved, and there is a lack of support for users' diverse dynamic color needs.

[0005] To achieve the above objectives, the present invention is implemented through the following technical solutions: A method for controlling light color shift, comprising the following steps:

[0006] S1. Receive target color data and offset parameters through a user interface;

[0007] S2. Use the ambient light sensor to collect the ambient color temperature T amb , monitor the LED module junction temperature T through the PT1000 temperature sensor led ;

[0008] S3, based on the offset parameter of step S1 and the ambient color temperature T collected in step S2 amb and LED module junction temperature T led , calculate color compensation parameters;

[0009] S4, generating three-channel RGB PWM signals and white light channel PWM signals through the improved HSV-RGB bidirectional conversion model, totaling four-channel driving signals;

[0010] S5. Use the spectrophotometer to feedback the actual color coordinates and adjust the color error through double closed-loop control.

[0011] Preferably, in S1, the target color data is based on the CIE1931 standard, and the offset parameters are used to generate a dynamic color offset effect, and the offset parameters include:

[0012] Periodic function parameters: using the formula Generates periodic color fluctuations, where f is the frequency, which is used to control the periodic rate of color shift. is the initial phase, which is used to determine the starting phase of color fluctuation;

[0013] Random perturbation parameter: A random value in the range of δ∈[-3%,+3%] is used to superimpose a random offset on the target color;

[0014] Gradient slope parameter: Use the formula Defines the hue gradient rate, where ΔH is the hue change amount and Δt is the change time.

[0015] Preferably, in S3, the color compensation parameter is calculated by predicting the color coordinate offset using the following regression model:

[0016] ΔC=f(T amb ,T led ,C hist ), where C list For historical color coordinate data, T is established through fuzzy logic algorithm amb 、T led Nonlinear mapping relationship with RGBW four-channel color mixing weights.

[0017] Preferably, in S4, the improved HSV-RGB bidirectional conversion model includes:

[0018] Hue calculation: H = (target hue angle + offset) % 360, where the offset includes the periodic function of step S1, random perturbation, and compensation offset of step S3;

[0019] Saturation calculation: S = basic saturation × (1 + environmental compensation coefficient), where the environmental compensation coefficient is calculated by T amb Sure;

[0020] Luminance calculation: V = initial luminance × luminance attenuation factor, where the luminance attenuation factor is equal to T led Positive correlation;

[0021] Through the four-dimensional lookup table LUT (H, S, T amb ,T led ) compensates for LED discreteness and combines the brightness calculation result V to generate three-channel RGB PWM signals and a white light channel PWM signal, totaling four-channel drive signals, corresponding to the RGBW four-color LED module.

[0022] Preferably, in S5, the dual closed-loop control includes:

[0023] Current inner loop: The current stability is controlled to <0.5% and the response time is <200μs by the PID algorithm. The PID algorithm uses the following formula:

[0024] Where e(t) is the current error;

[0025] Color outer ring: The color coordinates are adjusted by the above fuzzy PID algorithm, and the parameters are

[0026] K P =0.8, K I =0.05, K D =0.12, the temperature compensation coefficient is 0.3%;

[0027] When the color coordinate error ΔE ≥ 2 fed back by the spectrophotometer, recalibration is triggered.

[0028] Preferably, the RGBW four-channel color mixing weight ratio is 5:3:3:2, wherein the white light channel is used to compensate for color temperature drift, and the weight coefficient is related to T amb The relationship is

[0029] Preferably, in said S1, the user interaction interface supports storing preset scenes, and stores ≥1000 sets of three-dimensional color trajectory data with time axis in NVRAM through index compression algorithm, each set of data includes time axis. i And the corresponding (H i ,S i ,V i ).

[0030] Preferably, in step S4, the color conversion and compensation calculation are performed by an FPGA hardware acceleration unit.

[0031] Preferably, the output power is distributed to the bus power through a dynamic load balancing algorithm, using the following formula:

[0032] P bus =∑(P i ×α i ), where P i is the power demand of each channel, and the red channel priority coefficient α R =1.2, blue channel alpha B =0.8, the over-temperature protection threshold is 85℃ for the red channel and 75℃ for the blue channel.

[0033] Preferably, a control system for light color shift includes the following modules:

[0034] User interaction module: includes a TFTLCD operation panel that supports HSL / RGB input, is used to receive CIE1931 standard color coordinates and offset parameters, and store preset scenes;

[0035] Main control processing module: equipped with ARMCortex-M3 processor and FPGA acceleration unit, used to execute multi-sensor data fusion algorithm, improved HSV-RGB conversion model and dual closed-loop control algorithm;

[0036] Drive execution module: contains four-channel PWM constant current driver, used to generate PWM signal with frequency of 500Hz-25kHz according to the main control instruction;

[0037] Lighting array module: uses RGBW four-color LED module, integrates optical lens, diffuser and PT1000 temperature sensor, and supports 5:3:3:2 weighted color mixing;

[0038] Sensor feedback module: includes ALS ambient light sensor and spectrophotometer, used to collect T amb 、T led And color coordinate error data:

[0039] Storage module: Contains NVRAM memory and index compression unit, used to store ≥1000 sets of three-dimensional color trajectory data with time stamps.

[0040] The present invention provides a method and system for controlling light color shift, which has the following beneficial effects:

[0041] 1. The present invention receives target color data and offset parameters, and collects ambient color temperature and LED module junction temperature data to provide basic input and real-time status information for color compensation calculation, enabling the system to dynamically adjust color parameters based on user needs and environmental equipment status, thereby improving the targetedness and environmental adaptability of color control.

[0042] 2. The present invention calculates color compensation parameters based on offset parameters and sensor data, and then uses an improved HSV-RGB bidirectional conversion model to generate PWM drive signals. It deeply integrates dynamic effect parameters with environmental compensation parameters to achieve precise conversion and compensation of color parameters, ensuring that the generated drive signal can accurately present the target color and dynamic offset effect.

[0043] 3. The present invention uses a spectrophotometer to feedback the actual color coordinates and adopts dual closed-loop control to adjust the color error, forming a real-time closed-loop feedback mechanism, continuously monitoring the color output error and automatically correcting it, effectively overcoming the color deviation caused by environmental changes and equipment operation, and ensuring the stability and accuracy of the light color.

[0044] 4. The present invention constructs a complete control process from color parameter input, data calculation, drive signal generation to error feedback adjustment through the coordinated operation of modules such as user interaction, main control processing, drive execution, and sensor feedback in the system, thereby realizing automated and intelligent control of light color deviation, meeting the needs of diverse scenarios for precise dynamic color effects, and improving the system's operational convenience and application flexibility. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 This is a flow chart of a method for controlling light color shift according to the present invention;

[0046] Figure 2 This is a system architecture diagram of a light color shift control system according to the present invention. DETAILED DESCRIPTION

[0047] The following will clearly and completely describe the technical solution of the present invention in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0048] Please see the attached Figure 1 , an embodiment of the present invention provides a method for controlling light color shift, comprising the following steps:

[0049] S1. Receive target color data and offset parameters through a user interface;

[0050] S2. Use the ambient light sensor to collect the ambient color temperature T amb , monitor the LED module junction temperature T through the PT1000 temperature sensor led ;

[0051] S3, based on the offset parameter of step S1 and the ambient color temperature T collected in step S2 amb and LED module junction temperature T led , calculate color compensation parameters;

[0052] S4, generating three-channel RGB PWM signals and white light channel PWM signals through the improved HSV-RGB bidirectional conversion model, totaling four-channel driving signals;

[0053] S5. Use the spectrophotometer to feedback the actual color coordinates and adjust the color error through double closed-loop control.

[0054] Specifically, in step S1, human-computer interaction is implemented through a user interface, allowing the user to input target color data and offset parameters, providing basic input for subsequent color offset control, and ensuring that the system can generate corresponding color effects according to user needs;

[0055] In step S2, the ambient light sensor and PT1000 temperature sensor collect the ambient color temperature and LED module junction temperature in real time, providing real-time environmental data and device status data for the system to calculate color compensation parameters, so that the color offset control can adapt to environmental changes and device operating status;

[0056] In step S3, the color compensation parameters are calculated by combining the offset parameters input by the user and the real-time sensor data collected. This combines user needs with the environment and device status to achieve accurate prediction and compensation of color offset, thereby improving the accuracy of color control.

[0057] In step S4, the color parameters are converted using the improved HSV-RGB bidirectional conversion model to generate a PWM drive signal, which provides a specific control signal for driving the LED module to ensure accurate output of the target color and offset effect.

[0058] In step S5, the actual color coordinates are fed back by the spectrophotometer, and the color error is adjusted in combination with the dual closed-loop control mechanism to form a closed-loop feedback control, correct the color offset in real time, and ensure the accuracy and stability of the output color.

[0059] In S1, the target color data is based on the CIE1931 standard, and the offset parameters are used to generate a dynamic color offset effect. The offset parameters include:

[0060] Periodic function parameters: using the formula Generates periodic color fluctuations, where f is the frequency, which is used to control the periodic rate of color shift. is the initial phase, which is used to determine the starting phase of color fluctuation;

[0061] Random perturbation parameter: A random value in the range of δ∈[-3%,+3%] is used to superimpose a random offset on the target color;

[0062] Gradient slope parameter: Use the formula Defines the hue gradient rate, where ΔH is the hue change amount and Δt is the change time.

[0063] Specifically, the CIE1931 standard is a color measurement standard developed by the International Commission on Illumination. The target color data based on this standard has a unified and standardized color expression basis, which can ensure the accuracy and consistency of color description, making the understanding and presentation of color more accurate in different devices and different scenarios, and facilitating the system to accurately receive and process the user's expected color target. The offset parameter can generate a dynamic color offset effect, giving the light color a dynamic change attribute, breaking through the limitations of static color, and meeting diverse and personalized lighting needs. For example, in scenes such as stage lighting and atmosphere creation, it can create rich and varied visual effects. For example, in the scene where stage lighting simulates the breathing light effect, setting f = 0.5Hz means that the color fluctuation period is 2 seconds. Then the light color will fluctuate regularly from the initial color in a 2-second cycle according to the sine function. By controlling the cycle rate of color shift by f, the number of light color fluctuations per unit time can be accurately adjusted to meet the dynamic needs of different rhythms. Determining the starting phase of color fluctuations allows multiple lighting devices to have different starting points for color fluctuations, creating a more layered and staggered dynamic lighting effect. For example, simulating a natural flame lighting effect, we randomly superimpose δ values ​​on a target yellow light. Assuming the target color brightness is 100, when δ is randomly set to +2%, the brightness becomes 102, and when δ is randomly set to -1%, the brightness becomes 99. Adding a random offset to the target color can make the light color appear to flicker naturally and irregularly, simulating a random dynamic effect similar to natural flames and enhancing the realism and visual appeal of the lighting. For example, when simulating the lighting changes in a sunset scene, we set ΔH to 30° and Δt to 30 seconds for the hue to gradually change from orange to red. Using the formula, we obtain k = 1° / s, indicating a hue gradient of 1° per second. ΔH, as the hue change amount, determines the color gradient span, and Δt, as the change time, combines these two to precisely control the hue gradient rate, achieving delicate adjustment of the light color gradient process and creating a realistic scene atmosphere.

[0064] In S3, the color compensation parameter calculation predicts the color coordinate offset through the following regression model:

[0065] ΔC=f(T amb ,T led ,C hist ), where C list For historical color coordinate data, T is established through fuzzy logic algorithm amb 、T led Nonlinear mapping relationship with RGBW four-channel color mixing weights.

[0066] Specifically, in the light color deviation control, the regression model ΔC=f(Tamb ,T led ,C list ) predicts the color coordinate offset, for example, in an indoor lighting scene, as the ambient temperature T amb Increase, LED module junction temperature T led will also change, and combined with the previously recorded historical color coordinate data C hist , the model can calculate the excellent coordinate offset ΔC, and the fuzzy logic algorithm establishes T amb 、T led The nonlinear mapping relationship with the RGBW four-channel color mixing weights can intelligently adjust the RGBW four-channel color mixing weights according to changes in the environment and device temperature. When used in conjunction, it can comprehensively consider factors such as ambient color temperature, LED junction temperature, and historical color coordinates to accurately predict color coordinate offsets and dynamically adjust the color mixing weights, effectively compensating for color deviations caused by changes in the environment and device status, thereby ensuring that the light color always meets expectations and improving the accuracy and stability of the lighting system's color output.

[0067] In S4, the improved HSV-RGB bidirectional conversion model includes:

[0068] Hue calculation: H = (target hue angle + offset) % 360, where the offset includes the periodic function in step S1, the random perturbation, and the compensation offset in step S3;

[0069] Saturation calculation: S = basic saturation × (1 + environmental compensation coefficient), where the environmental compensation coefficient is calculated by T amb Sure;

[0070] Luminance calculation: V = initial luminance × luminance attenuation factor, where the luminance attenuation factor is equal to T led Positive correlation;

[0071] Through the four-dimensional lookup table LUT (H, S, T amb ,T led ) compensates for LED discreteness and combines the brightness calculation result V to generate three-channel RGB PWM signals and a white light channel PWM signal, totaling four-channel drive signals, corresponding to the RGBW four-color LED module.

[0072] Specifically, in hue calculation, the formula H = (target hue angle + offset) % 360. For example, if the target hue angle is 60°, the offset generated by the periodic function, random perturbation in step S1, and the compensation offset in step S3 is 10°, then the new hue angle calculated is 70°. By integrating multiple offset factors, the hue can accurately reflect user needs and changes in environmental equipment status. In saturation calculation, S = basic saturation × (1 + environmental compensation coefficient). If the ambient color temperature T ambThe determined environmental compensation coefficient increases the saturation appropriately. For example, if the basic saturation is 0.5 and the environmental compensation coefficient is 0.1, the saturation becomes 0.55 after calculation, realizing the adaptive adjustment of saturation with environmental changes. In the brightness calculation, V = initial brightness × brightness attenuation factor. When the junction temperature of the LED module T led As the brightness rises, the brightness attenuation factor increases. If the initial brightness is 0.8 and the brightness attenuation factor is 1.2, the brightness becomes 0.96 after calculation. The brightness can be reasonably adjusted according to the LED junction temperature. Finally, the four-dimensional lookup table LUT (H, S, T amb ,T led ), compensates for LED discreteness, generates four-channel PWM control signals, and comprehensively considers hue, saturation, brightness, as well as environmental and device temperature factors to achieve precise control of LED light color, ensuring that the output color meets expectations and is stable and consistent.

[0073] In S5, dual closed-loop control includes:

[0074] Current inner loop: The current stability is controlled by the PID algorithm to be <0.5% and the response time is <200μs. The PID algorithm uses the following formula:

[0075] Where e(t) is the current error;

[0076] Color outer ring: The color coordinates are adjusted by the above fuzzy PID algorithm, and the parameters are

[0077] K P =0.8, K I =0.05, K D =0.12, the temperature compensation coefficient is 0.3%;

[0078] When the color coordinate error ΔE ≥ 2 fed back by the spectrophotometer, recalibration is triggered.

[0079] Specifically, the current inner loop uses the PID algorithm Calculation is based on the current error e(t). For example, when the actual current has an error of e(t) = 0.1A, K P =0.2,K I =0.05, K D =0.1, the control quantity u(t) can be calculated by the formula, and then the current is adjusted to achieve a current stability of less than 0.5% and a response time of less than 200μs, ensuring the stable power supply of the LED module and providing a basis for stable color output. The color outer loop uses a fuzzy PID algorithm, and the parameter K P =0.8, K I =0.05, K D=0.12, with a temperature compensation coefficient of 0.3%. The color coordinates are adjusted based on the color coordinate error reported by the spectrophotometer. If the color coordinate error ΔE ≥ 2, recalibration is triggered to correct color deviations in real time to ensure the accuracy of light color. This collaborative effort from both current and color dimensions ensures the stability and accuracy of the lighting system's color output.

[0080] The RGBW four-channel color mixing weight ratio is 5:3:3:2, where the white light channel is used to compensate for color temperature drift, and the weight coefficient is related to T amb The relationship is

[0081] Specifically, the RGBW four-channel color mixing weight ratio is set to 5:3:3:2, which can reasonably coordinate the color mixing effects of the red, green, blue and white channels. The white light channel is specifically used to compensate for color temperature drift. Combined with the weight coefficient and T amb The relationship formula For example, when the ambient color temperature T amb =4200K, we can get By dynamically adjusting the white light channel weight coefficient according to the ambient color temperature, the color temperature drift caused by ambient temperature changes can be effectively compensated, ensuring that the light can maintain stable and accurate color temperature output under different environmental conditions, and improving the color stability and environmental adaptability of the lighting system.

[0082] In S1, the user interface supports the storage of preset scenes, and stores ≥1000 sets of 3D color trajectory data with time axis in NVRAM through index compression algorithm. Each set of data contains time axis. i And the corresponding (H i ,S i ,V i ).

[0083] Specifically, the user interface supports the storage of preset scenes, and uses the index compression algorithm to store no less than 1000 sets of three-dimensional color trajectory data with time axis in NVRAM, each set of data contains a timestamp t i And the corresponding (H i ,S i ,V i ), this function can realize the recording and storage of various lighting scenes. For example, in a stage performance, the lighting engineer can set up and store lighting scenes corresponding to multiple different performance links in advance, such as the warm and cheerful lighting scene at the beginning of the performance. The timestamp is t1 when the performance starts, and the corresponding hue H1, saturation S1, and brightness V1 are specific numerical combinations. As the performance progresses, the corresponding scene can be quickly called according to the timeline, which greatly improves the convenience and flexibility of lighting control and meets the needs of complex and changing scenes. At the same time, the index compression algorithm effectively saves storage space and ensures efficient storage and fast retrieval of large amounts of data.

[0084] In step S4, the color conversion and compensation calculation are performed by the FPGA hardware acceleration unit.

[0085] Specifically, color conversion and compensation calculations are performed by the FPGA hardware acceleration unit. The FPGA has parallel processing characteristics. For example, when processing a large number of color data conversion and compensation calculation tasks, it can calculate multiple color parameters at the same time, which greatly shortens the processing time compared to traditional software calculation methods. By performing related calculations through it, it can achieve μs-level response, meeting the needs of real-time and rapid adjustment of light color. Especially in scenarios with high requirements for timeliness of color changes, such as rapid switching of stage lights, real-time adjustment of lights on film and television shooting, it can quickly and accurately convert the calculation results into PWM drive signals, ensuring the efficiency and accuracy of light color offset control, and improving the performance of the entire lighting system.

[0086] The output power is distributed across the bus using a dynamic load balancing algorithm using the following formula:

[0087] P bus =∑(P i ×α i ), where P i is the power demand of each channel, and the red channel priority coefficient α R =1.2, blue channel alpha B =0.8, the over-temperature protection threshold is 85℃ for the red channel and 75℃ for the blue channel.

[0088] Specifically, through the dynamic load balancing algorithm P bus =∑(P i ×α i ) distributes bus power according to the power requirements of each channel P i and priority coefficient α i Reasonable power allocation, for example, assuming the red channel requires power P R =100W, blue channel power requirement P B =80W, according to the formula, the red channel has a priority coefficient α R =1.2, the allocated power is relatively more, the blue channel α B =0.8 allocates relatively less power. This allocation method ensures that under limited bus power, the power supply of important channels is prioritized while taking other channels into consideration. In addition, the over-temperature protection threshold of the red channel is set at 85°C and that of the blue channel is set at 75°C. When the channel temperature reaches the threshold, the power allocation can be adjusted in time to avoid damage to the equipment due to overheating, ensure the stable and safe operation of the lighting system, and extend the service life of the equipment.

[0089] Please see the attached Figure 2, a control system for light color shift, the system includes the following modules:

[0090] User interaction module: includes a TFTLCD operation panel that supports HSL / RGB input, is used to receive CIE1931 standard color coordinates and offset parameters, and store preset scenes;

[0091] Main control processing module: equipped with ARMCortex-M3 processor and FPGA acceleration unit, used to execute multi-sensor data fusion algorithm, improved HSV-RGB conversion model and dual closed-loop control algorithm;

[0092] Drive execution module: contains four-channel PWM constant current driver, used to generate PWM signal with frequency of 500Hz-25kHz according to the main control instruction;

[0093] Lighting array module: uses RGBW four-color LED module, integrates optical lens, diffuser and PT1000 temperature sensor, and supports 5:3:3:2 weighted color mixing;

[0094] Sensor feedback module: includes ALS ambient light sensor and spectrophotometer, used to collect T amb 、T led And color coordinate error data:

[0095] Storage module: Contains NVRAM memory and index compression unit, used to store ≥1000 sets of three-dimensional color trajectory data with time stamps.

[0096] Specifically, the user interaction module includes a TFTLCD operation panel that supports HSL / RGB input and can receive CIE1931 standard color coordinates and offset parameters, providing users with an intuitive and convenient interaction method, allowing users to easily input desired color targets and dynamic effect parameters. It can also store preset scenes to meet users' needs for quick call of different lighting scenes, improving flexibility and convenience of use.

[0097] The main control processing module, equipped with an ARM Cortex-M3 processor and an FPGA acceleration unit, can execute multi-sensor data fusion algorithms, improved HSV-RGB conversion models, and dual closed-loop control algorithms. Its powerful hardware configuration and rich algorithm support can efficiently process data collected by sensors, accurately implement color conversion and compensation calculations, and closed-loop control, ensuring the accuracy and real-time performance of light color offset control.

[0098] The driver execution module includes a four-channel PWM constant-current driver that can generate PWM signals with a frequency of 500Hz-25kHz according to the master control instructions. This provides a stable and adjustable drive signal for the LED module, achieving precise control of light color, brightness and other parameters. It is the key execution link that converts the master control instructions into actual lighting effects.

[0099] The lighting array module uses RGBW four-color LED modules, integrated with optical lenses, diffusers, and PT1000 temperature sensors. It supports 5:3:3:2 weighted color mixing. RGBW four-color combinations and specific weighted color mixing can achieve rich color output. The optical lens and diffuser optimize the lighting effect, and the temperature sensor monitors the junction temperature in real time to ensure stable system operation.

[0100] Sensor feedback module, including ALS ambient light sensor and spectrophotometer, for real-time acquisition of T amh 、T ed Color coordinate error data provides the system with environmental and equipment status information, enabling the system to adjust color parameters in a timely manner according to actual conditions to ensure the accuracy and stability of lighting color;

[0101] The storage module includes NVRAM memory and index compression unit, which is used to store ≥1000 sets of three-dimensional color trajectory data with timestamps. It can record and save a large amount of lighting scene data. The index compression unit improves storage efficiency and facilitates users to call historical scene data at any time to meet diverse lighting control needs.

[0102] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the invention, and the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A method for controlling light color shift, characterized in that: The following steps are involved: S1. Receive target color data and offset parameters through a user interface; S2. Use the ambient light sensor to collect the ambient color temperature T amb , monitor the LED module junction temperature T through the PT1000 temperature sensor led ; S3, based on the offset parameter of step S1 and the ambient color temperature T collected in step S2 amb and LED module junction temperature T led , calculate the color compensation parameters: S4, generating a PWM driving signal through an improved HSV-RGB bidirectional conversion model; S5. Use the spectrophotometer to feedback the actual color coordinates and adjust the color error through double closed-loop control.

2. The method for controlling light color shift according to claim 1, wherein: In S1, the target color data is based on the CIE1931 standard, and the offset parameters are used to generate a dynamic color offset effect. The offset parameters include: Periodic function parameters: using the formula Generates periodic color fluctuations, where f is the frequency, which is used to control the periodic rate of color shift. is the initial phase, which is used to determine the starting phase of color fluctuation; Random perturbation parameter: A random value in the range of δ∈[-3%,+3%] is used to superimpose a random offset on the target color; Gradient slope parameter: Use the formula Defines the hue gradient rate, where ΔH is the hue change amount and Δt is the change time.

3. The method for controlling light color shift according to claim 1, wherein: In S3, the color compensation parameter calculation predicts the color coordinate offset through the following regression model: ΔC=f(T amb ,T led ,C hist ), where C list For historical color coordinate data, T is established through fuzzy logic algorithm amb 、T led Nonlinear mapping relationship with RGBW four-channel color mixing weights.

4. The method for controlling light color shift according to claim 1, wherein: In S4, the improved HSV-RGB bidirectional conversion model includes: Hue calculation: H = (target hue angle + offset) % 360, where the offset includes the periodic function of step S1, random perturbation, and compensation offset of step S3; Saturation calculation: S = basic saturation × (1 + environmental compensation coefficient), where the environmental compensation coefficient is calculated by T amb Sure; Luminance calculation: V = initial luminance × luminance attenuation factor, where the luminance attenuation factor is equal to T led Positive correlation; Through the four-dimensional lookup table LUT (H, S, T amb ,T led ) compensates for LED discreteness and combines the brightness calculation result V to generate three-channel RGB PWM signals and a white light channel PWM signal, totaling four-channel drive signals, corresponding to the RGBW four-color LED module.

5. The method for controlling light color shift according to claim 1, wherein: In S5, the dual closed-loop control includes: Current inner loop: The current stability is controlled to <0.5% and the response time is <200μs by the PID algorithm. The PID algorithm uses the following formula: Where e(t) is the current error; Color outer ring: The color coordinates are adjusted by the above fuzzy PID algorithm, and the parameter is K P =0.8, K I =0.05, K D =0.12, the temperature compensation coefficient is 0.3%; When the color coordinate error ΔE ≥ 2 fed back by the spectrophotometer, recalibration is triggered.

6. The method for controlling light color shift according to claim 3, wherein: The RGBW four-channel color mixing weight ratio is 5:3:3:2, where the white light channel is used to compensate for color temperature drift, and the weight coefficient is related to T amb The relationship is 7. The method for controlling light color shift according to claim 1, wherein: In the S1, the user interface supports the storage of preset scenes, and stores ≥1000 sets of three-dimensional color trajectory data with time axis in NVRAM through index compression algorithm, each set of data contains time axis. i And the corresponding (H i ,S i ,V i ).

8. The method for controlling light color shift according to claim 1, wherein: In step S4, the color conversion and compensation calculation are performed by the FPGA hardware acceleration unit.

9. The method for controlling light color shift according to claim 1, wherein: The output power is distributed through the bus power through a dynamic load balancing algorithm, using the following formula: P bus =∑(P i ×α i ), where P i The power required for each channel, the red channel priority coefficient α R =1.2, blue channel alpha B =0.8, the over-temperature protection threshold is 85℃ for the red channel and 75℃ for the blue channel.

10. A light color shift control system, used in a light color shift control method according to any one of claims 1 to 9, characterized in that: The system includes the following modules: User interaction module: includes a TFTLCD operation panel that supports HSL / RGB input, is used to receive CIE1931 standard color coordinates and offset parameters, and store preset scenes; Main control processing module: equipped with ARMCortex-M3 processor and FPGA acceleration unit, used to execute multi-sensor data fusion algorithm, improved HSV-RGB conversion model and dual closed-loop control algorithm; Drive execution module: contains four-channel PWM constant current driver, used to generate PWM signal with frequency of 500Hz-25kHz according to the main control instruction; Lighting array module: uses RGBW four-color LED module, integrates optical lens, diffuser and PT1000 temperature sensor, and supports 5:3:3:2 weighted color mixing; Sensor feedback module: includes ALS ambient light sensor and spectrophotometer, used to collect T amb 、T led And color coordinate error data: Storage module: Contains NVRAM memory and index compression unit, used to store ≥1000 sets of three-dimensional color trajectory data with time stamps.

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