Performance prediction of annular linear induction pump under constant slip frequency operation

Abstract This paper predicts the performance of annular linear induction pumps (ALIPs) under constant slip frequency operation mode. Predictions are made using a two-dimensional finite element method (FEM) based model. Two pumps, one with medium gap and other of large gap, are analyzed. Effect of constant slip frequency operation on important parameters like developed pressure, input current, efficiency has been studied. Comparison with normal constant frequency fixed voltage operation of ALIP is also presented. It is observed that constant slip frequency operation leads to higher efficiencies due to lower losses. Operation at constant slip frequency makes skin depth and magnetic Reynolds number constant even when flow decreases. Using different V / f modes with constant slip frequency, the pressure-flow characteristics of ALIP can be modified to meet different load characteristics.