Acoustic noise reduction in VSI-DFIM for electrical naval propulsion

In this paper, the authors treat one of the major problems noted in the association of electrical motors fed by the inverters, it is well known as the acoustic and vibratory noise. An electrical propulsion system mainly based on a Doubly Fed Induction Machine (DFIM), operating in motor mode and supplied by two Voltage Source Inverters (VSIs) is introduced. The modeling of the marine propeller is reported and the equations defining its behavior are established. A Stator Flux Oriented Control (SFOC) associated to different modulators (PWM) is chosen 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 in term of acoustic noise, these laws are evaluated during a cruise cycle.