Design of intelligent lighting system for plants with high uniformity

At present, the plant light sources in most plant factories have problems such as low uniformity of illumination and single supplementary light mode, which lead to the failure of plants to achieve the best growth state during the growth process. Aiming at such problems, this paper studies and designs an intelligent supplementary light system with high uniformity and spectral adjustment at different growth stages of plants. The system can monitor the ambient temperature and light intensity, change the pulse-width modulation output according to the system’s preset value, and control the brightness of the red and white LEDs by changing the current of the LED so as to achieve the purpose of adjusting the spectrum. According to the plant light formula, the light quality ratio of red light to blue light in the light spectrum should reach 7:1 at most, and the proportion of green light should not be more than 25%, and the maximum luminous quantum flux density of a single LED flat panel light source should be around 100 μmol·m−2·s−1 at the receiving surface at a vertical distance of 30 cm. The test results show that the illumination uniformity of the system reaches 91.67%, the light source system can be accurately changed according to the set light formula, and the light quality ratio in the light source spectrum is consistent with the preset value, which shows that the light system can be well used in the field of plant growth lighting.