<b>Use of the frequency inverter on center pivot irrigation system and its effects on water depth and water distribution uniformity</b>

Abstract

This study aimed to evaluate the uniformity of distribution and water depth applied with a center pivot irrigation systems according to the change in speed of rotation of set motor pump with a frequency inverter and the effect of the position of the lateral line in these parameters. Three positions of lines of collecting water were tested: incline of 3.45%, level and slope of 11.78%. The experimental design was completely randomized, with three replications made at each position tested. Analysis of variance was applied followed by Tukey test. The average value of the coefficient of uniformity of Heermann e Hein was 88.85%, describing the uniformity of water distribution as good. The mean weighed depth of irrigation applied was 5.71 mm, varying significantly within each test (5%) between the positions of slope versus incline and level. It was concluded that the position of the lateral line influenced significantly in the rotation the set motor pump, water depth applied and energy consumption. However, in the values of uniformity of water distribution there was no difference.