Abstract:Aiming at the problems of low environmental perception accuracy, lagged control response, poor communication reliability, weak system integration and high operation cost in large-scale multi-span greenhouses in China, taking a 22000m2 Venlo-type glass multi-span greenhouse in Tongzhou District, Beijing as the experimental platform, an edge intelligent controller was designed based on STM32H750. A four-layer IoT architecture, including perception, control, transmission, and application, was constructed, and an intelligent collaborative environmental monitoring system was developed with multidimensional perception, zonal linkage, hybrid communication self-healing and cloud-edge collaborative management. The system adopted key technologies such as hardware modular photoelectric isolation, software redundancy and fault tolerance, temperature-humidity coupling decoupling, hierarchical collaborative fuzzy PID control, zonal energy consumption optimization, offline data transmission and adaptive link switching, which solved the problem of long-term stable operation under high temperature, high humidity and strong electromagnetic interference. The 72-hour continuous test and full growth period experiment showed that the data acquisition cycle was 1s, the control response time was (0.7±0.2)s, the equipment execution lag was 4.2~8.5s, the communication packet loss rate was no more than 0.1% , the steady-state error of temperature control was controlled within a ±0.4℃, and the control error of relative humidity was controlled within a ±2.7%. The temperature fluctuation was controlled within a ±0.5℃ and humidity fluctuation was controlled within a ±3% under day-night conditions. Compared with the traditional scheme, the energy consumption was reduced by 18.6% , the manual operation and maintenance cost was decreased by 62.3% , the tomato yield was increased by 12.7% , and the disease incidence was reduced by 41.3% (P<0.01), with a static payback period of 1.7 years. The research results could provide technical support for intelligent production in large-scale multi-span greenhouses.