Projeto e compensação de parâmetros de transformador de núcleo separado destinado ao carregamento de baterias de veículos subaquáticos autônomos

Abstract

This work presents a study on contactless electrical energy power transfer for charging batteries of autonomous underwater vehicles (AUV - Autonomous Underwater Vehicles) using transformers with separated core (TNS). Initially, a project is made for building a transformer with separated core. After, the equations that model the operation of the transformer, based on its electrical equivalent circuit, are developed. Then, the work proposes an alternative to estimate the parameters of the equivalent circuit of the transformer operating with different gap values, validating its mathematical model with simulations in PSIM software, version 9.0. With the mathematical model of TNS, an evaluation of its ability to transfer power is made, showing that, because of the air gap, the transformer has a low efficiency and low output voltage. Therefore, methodologies to compensate for the effects of voltage drop in the leakage impedance and increase the efficiency of the transformer are investigated by introducing capacitances in the equivalent circuit and varying the of operating frequency. Applying the results of optimization methodology is shown, through laboratory experiments, that the TNS is capable of transmitting power through an air gap of 10 mm, given the voltage and load power conditions, with relatively high efficiency. Then, an experiment is done with seawater in order to verify the applicability of TNS for underwater vehicles. Finally, the work presents a simulation in PSIM with a d.c./d.c. charge controller for battery. The results demonstrate the operation of the system, verifying the methodology for estimation of the model and optimization methodology of TNS.