Research And Application Of Color Stability And Color Mixing Optimization Of White LEDs

Nowadays,Energy-saving and environmentally-friendly is the strategic direction of development,which is actively promoted around the world.People's pursuit of high quality life continues to improve with the development of economy.As a new generation of light source,LED lamp is gradually replacing the traditional light source with the advantages of high-efficiency,long-lifetime,energy-saving,environmentally-friendly and rapid-response etc.Nowadays,LED lamps are widely used in home lighting,office lighting,atmosphere lighting and special lighting.Due to the low power of single chip LED,multiple LED chips are combined to use in practical applications.In order to improve the color stability of LED lamp in dimming and the color mixing illumination quality of multi color LEDs,in this paper,the color stability of LED lamp and the color mixing illumination of multi color LEDs are studied bases on intelligent control algorithm,and the optimization strategy of LEDs color mixing illumination is applied to solar simulation to achieve high performance solar simulation.In this paper,the research method of combination of theoretical analysis and simulation,experimental verification is adopted.The main research results are as follows:1.Aiming at the color shift of LED lamp in dimming,this paper analysed the main factors affecting the color stability of LED lamp in dimming,and proposed a predictive control strategy based on BP neural network.The strategy can reduce the color shift of LED lamp in PWM dimming through accurately predicting the optimal peak current that can maintain the color stability of LED lamp in PWM dimming.Finally,the effectiveness of the strategy is verified by experiments.2.Aiming at optimization of RGBW four-color LEDs color mixing illumination,this paper derived the relationship between color temperature,luminous flux,color index of mixed light and PWM dimming duty cycle based on RGBW four-color LEDs color mixing illumination equation.Based on this,this paper further proposed using genetic algorithm to optimize the luminous flux and color index of mixed light to obtain optimal lighting performance.Finally,the effectiveness of the strategy is verified by experiments.3.Aiming at optimization of illumination uniformity of LED array,this paper established the mathematical model of illumination distribution of LED array,and proposed using genetic algorithm to optimize the distribution of LED array.The strategy can obtain the optimal distribution of LED array,and the effectiveness of the optimization strategy is verified by simulation and experiment.4.From the practical point of view,The optimization strategy of RGBW four-color LEDs color mixing illumination is applied to solar simulation.By adjusting each LED' PWM duty cycle,not only allow LEDs mixed light to accurately simulate change regulation of color temperature and brightness of diurnal solar light,but also can obtain better solar simulation performance through optimizing the color index of LEDs mixed light by genetic algorithm.Finally,the solar simulation is achieved by experiments.The research results obtained in this paper have a good theoretical guidance and practical reference significance in improving the lighting quality of LED lamps.