Research And Design Of LED Light Environment Control System In Plant Factory

LED is regarded as one of the important technical means for revolutionary breakthrough in agriculture in the 21 st century.However,LED lighting product with proprietary intellectual property rights is absent in the field of vegetable farming in Chinese plant factory.Therefore,LED plant light source products and light environment control systems with high light evenness are researched,developed and designed in thisresearch.Based on the design standard of LED plant growth light and lighting calculation formula,the optical model of different LED array configuration forms is established with TracePro software in the research,the simulated analysis is implemented.At last,square array is selected as the LED array configuration form with relative high lighting uniformity.Moreover,the modelling for improvement and simulated analysis on square array are implemented in thisresearch.Results show that flexibly configuring LED according to the Spyros value in different positions of LED can enlarge the uniform area for plane of illumination accepting lighting significantly,improve the lighting uniformity of LED plant growth light.In addition,the hardware and software design of light environment control system is completed in thisresearch through selecting STM32 single chip as control chip,adopting PWM dimmer way,and combining with peripheral circuit in thisresearch.In the end,it is applied in the lettuce planting of plant factory,completing the lighting and light environment control on lettuce.It can be known through system measuring,uniform area accounts for about 65.5% of illumination area,red and blue light quality ratio is 5:1,and photoperiod is 12 h,which conforms to the design requirement of LED plant growth light.Meanwhile,the human-computer interaction interface of the designed light environment control system is simple and beautiful,with simple operation.Besides,the lettuce planted with this system has short growth cycle,the growth rate is consistent and the product consistency is pretty good.Therefore,LED plant growth light and light environment control system designed in this research can be applied into plant growth lighting field.