An article from the Proceedings of the 2018 Nebraska Extension Crop Production Clinics summarizes research to evaluate variable frequency drives (VFDs) on center pivots and the most effective placement of the pressure sensor.
Dilshad Brar, a graduate student in the UNL Biological Systems Engineering Department, looked at 1000 center pivot installations in 10 Nebraska counties to determine if placing a variable frequency drive (VFD) on the system would be economical. He also looked at the best location for the VFD pressure sensor. Brar breaks it down to four common scenarios, outlining when it pays and when it doesn't.
Heavy spring rains may have leached nitrogen from some soils. In-season chemigation applications can provide nitrogen when the plant most needs it and reduce the potential for leaching. To use chemigation, users must meet two major requirements: they must be certified to use chemigation and pollution prevention equipment must be installed at each injection location and inspected and approved by the local NRD.