Controle de conversor multinível modular para acionamento de um sistema de propulsão naval baseado em motor síncrono de ímãs permanentes

Abstract

This work presents a control strategy for a modular multilevel converter used to drive a marine propulsion system based on a permanent magnet synchronous motor. Initially, a review of the main architectures of electrical energy distribution in alternating current and direct current for naval applications is made. The mathematical model of the modular multilevel converter is presented, as well as the control strategies for the suppression of circulating currents and energy balance between converter arms. Additionally, the algorithm used to equalize the dc voltages of the submodules of the converter is shown. Next, the dynamic models of the motor-propeller set are presented and its strategy for controlling the speed of the permanent magnet motor used to drive the propeller is discussed. Altough the propulsion system is driven with variable speed, all controllers are designed in the synchronous coordinate frame. Results of digital simulations obtained with the PSIM program are used to validate the modeling and control strategies implemented for dierent operating conditions of the system