Electronic Filter Level Offset (EL-FLO) Plus RESET Equipment for Automatic Downstream Control of Canals

摘要

A prototype Electric Filter Level Offset (EL-FLO) plus RESET analog computer-controller for automatic downstream control of canal check gates was designed, constructed, and laboratory-tested at the Engineering and Research Center's Hydraulic Laboratory, Denver, CO. The EL-FLO plus RESET control system is designed to accommodate complex irrigation water delivery schedules with a high degree of self-regulation and maintains near constant water levels in a canal system. The sustained water level oscillations inherent in automatic flow regulation schemes are eliminated through the use of an electronic time delay circuit developed in this study. Laboratory tests of equipment performance under simulated canal bank environmental conditions were performed to ensure satisfactory operation at high temperatures, 65C (150F) and high humidity, 100 percent at 18C (64F). Laboratory simulation tests were performed to confirm that the prototype EL-FLO plus RESET analog computer-controller was designed and constructed as mathematically modeled. Upon completion of the laboratory development and testing, the prototype equipment was installed on the South Gila Canal near Yuma, AZ., to confirm equipment performance and reliability on an actual operating canal system. From the results of laboratory and field tests, specifications were written and 21 EL-FLO plus RESET controls units were procured for permanent installation on the Corning and Coalinga Canals in California. Initial installation of the procured units was made on the first four reaches of the Corning Canal near Red Bluff, CA., and field operation was continued to establish equipment performance and reliability. Field test data of the prototype and permanent installations are included in this report to demonstrate that the mathematical model does simulate the 'real' operating canal system with reasonable accuracy.