1.Farmland Irrigation Research Institute, MWR, CAAS, Xinxiang, Henan 453003, China; 2.Conservancy Bureau of Weihai City, Huancui District, Weihai, Shandong 264200, China
Abstract：In this paper the structure of automatic irrigaton system of distributing contant pressure,the design method of softwares and hardwares,and engineering examples are studied.The phenomenon of pipe explosion because of "water hammer"is avoided effectively through the applying of variable frequency speed regulation of multi-function and the implement of means of soft start and shut.The cost of engineering structure,maintainment and management are reduced greatly through the adoption of some measures,such as the distributing system structure,the combination of wire and wireless.By using the special circuit and the abnormal means of handlement,adding 100 V alternate current to the commom circuit point,we can solve the difficult problem of decayed circuit point which affect the long-term credibility of the system in the bad sitution.constant irrigation;automatic controlled system;variable frequency speed regulation;construction cost;maintain expenses
