The Mechanism And Method Of Real-time Feedback Control Border Irrigation Process Based On Surface Water Advance Data

At present, surface irrigation is still the most widely used field irrigation method in China. The irrigation management in field is extensive,and the control of irrigation process is poor,so it results in low field irrigation efficiency and surface irrigation performance indexes. this problem has become a bottleneck to restrict the development of surface irrigation technology in China. It has important theoretical and practical significance which studying on real-time precision control technology of surface irrigation process to trengthen the control and management of the irrigation process.Through the analysis of error condition for using partial data to estimate whole process based on a large number of measured flow data typical field, this paper researches on the adaptation of basin irrigation process real-time precision control technology; To explore the reasonable amount of data for accurately predicting irrigation process according to prior irrigaiton information based on Bayesian statistical methods; To establish the reverse optimization soil infiltration parameter model which used genetic algorithm to solve; Based on the observed data from typical field experiment and applied surface irrigation simulation model, this paper analyzes the effect on irrigation simulation account of the differences of dry and wet surface roughness or not; Through pre determine the water depth control objective which enables irrigation performance indexes to be optimized based on different irrigation elements, it can directly choose suitable water depth control objective according to irrigation elements in real-time control process.To build the system of basin irrigation process real-time precision control technology which considers obtaining information in real-time as support conditions, simulating and predicting irrigation process as core, decision and implementation of irrigation schemes as application platform.Through the study of the above content, the main conclusions and innovation point this paper lies in:(1)The average relative error between simulation value and measured values can be controlled about 40%,25%,15%,25% and 7%, when adopt the data amount of irrigation information is respectively 40%,50%,60%,70% and 80%;(2)This paper has established optimized reverse model for infiltration parameters, chosen the minimum average relative error (AREadv and AREh) for the measured and simulated values of advance time and surface water depth as the object function of the optimized reverse method of infiltration parameters, and adopted Genetic algorithm to solve the model which could satisfy the requirement of real-time control that calculation accuracy and timeliness;(3)Suitable irrigation depth control objective value needs to meet the irrigation performance indexes comprehensive optimal. Overall, Ea can achieve the optimum when the irrigation water depth control objective Zmin>0, while CU and ES can achieve optimum when the irrigation water depth control objective Zmin=Zreq. Ea, CU, and Es cannot simultaneously achieve optimum under the same control objective. The real-time control objectives for different irrigation conditions are different, when(L=50m), Zlq=Zreq is the best; When(L=100m,S0=0), Zmin>0 is the best;When(L=100m, S0≠ 0), Zlq=Zreq is the best; When(L=150m, S0≠ 0), clay loam,Sd=2cm, Zlq=Zreq is the best; but for other conditions, Zmin>0 is the best.;Through carried out the compared validation trail between basins implemented real-time control technology and adopted traditional technology, the results showed that irrigation performance indexes of basin implemented real-time control technology were superior to the basin adopted traditional technology, and it has enhanced the irrigation process management and increased the water efficiency.