Effects of Toshka Pumping Station Operations on Power Quality and Stability of Electrical Grid

Abstract

Abstract:Toshka is a large water pumping stations in Egypt. This station contains 21 units (18+3 Extentions) each 12MW. At a full capacity the full power consumptions can reach 200MW. The electrical feeding system for the stations contains; transformer, substations and Overhead transmission line (its long 300km), so the operations of the stations causes some problem for the electrical grid due to large value of power consumptions. In this paper, some problems were studied during the operations of the station. Effect of starting time on the station running and current consuming were studied. Also the effect of water level variations on the suctions side in Nasser Lake, speed changing, and power quality of the grid on the power consumptions. It was focused on the voltage and current variations, and the flicker occurred during the station operation. Finally the effects of number of harmonic filters used depending on the power rating of the unit, and effective short circuit ratio (ESCR) values on the stability of the electrical grid during the full load operations. The analyses of the results are obtained from actual measurement on the stations using modern power quality analyzers during different cases of operation are explained. This study is more useful for studying the problem occurred on the electrical grid during running of Toshka Stations, as it's a large station in Egypt and has special design, at different cases and conditions of operation.