VSI loss evaluation of DFIM drives for electrical naval propulsion

In this paper, the authors suggest a new design of propulsion system mainly based on a Doubly Fed Induction Machine (DFIM), operating in motor mode and supplied by two Voltage Source Inverters (VSIs). The modeling of the marine propeller is reported and the equations defining its behavior are established. A Stator Flux Oriented Control (SFOC) and Sliding Mode Control (SMC) are developed and associated to different modulators (PWM) to control the system. These control methods are applied considering taking into considerations a real naval propulsion operating cycle. In order to choose the optimal law to control the system described, these laws are evaluated with regard to switching loss during a cruise cycle.