Investigation And Modeling Of Voltage And Current Unbalance On A Three-phase Submersible Pump

Abstract

During the summer months of 2011, a North Texas subdivision experienced tripping difficulty with the submersible pump which is used to transfer water from an underground well to an above ground water storage tank. The tripping events were random in nature but occurred often. Under the suspicion that unbalanced phase voltages/currents are to blame, the local electrical cooperative sampled the line voltages/currents for several days in order to confirm the suspicions and better understand what the cause of the tripping events were. This thesis will discuss the analysis of that data and the development of a Simulink® based computer aided model which can be used to predict the behavior of both the submersible pump and the motor controller which is used to monitor and control the motor operation. It will be shown through analysis of the data that the motor protection system trips as a result of current unbalances repeatedly and that the computer aided model can accurately predict this as well as normal modes of operation.