Performance of a five-phase boost inverter-fed submersible induction machine

An electrical submersible pump (ESP) motor is preferably fed from a low voltage variable-frequency drive (VFD) followed by a step-up transformer. The motor and drive connection through a long feeder usually causes over voltage problems due to the travelling wave phenomenon, hence, filter networks on motor or inverter terminals are mandatory. The so-called boost-inverter intrinsically solves this problem as it offers a direct sinusoidal output voltage with voltage boosting capability. Hence, the conventional boosting stage and the filters can be dispensed with. This paper investigates the performance of a five-phase modular winding induction machine fed from a boost-inverter through a long feeder. The possible automated winding of a five-phase modular induction machine has stimulated its worthiness as an alternative to the conventional manually wound machines typically used in such applications. A simulation study using a 1000Hp system and experimental investigation on a 1Hp prototype machine are used to support the presented theory.