Controle da Tensão ou Corrente de Saída por Meio da Estimativa de Parâmetros em Sistema de Transferência de Energia Sem Fio Com Topologia Duplo-LCC

Abstract

Wireless Power Transfer (WPT) has emerged as a strategic technology of iinnovation, with strong potential impact on applications such as electric vehicle charging, micromobility systems, and portable electronic devices. Advances in efficient and robust WPT solutions play an important role in promoting sustainable mobility and supporting technological development. In Wireless Power Transfer Systems (WPTS), variations in the load connected to a receiver can cause instability in the waveforms of output voltage and current due to their sensitivity to changes in load impedance. To overcome such drawbacks, this paper presents a control scheme for regulating voltage and current at the output of a WPTS system with the double LCC topology, employing concentric solenoidal coils. The main contribution of this work lies in the development of a control strategy based on the estimation of the equivalent load impedance and the output voltage at the secondary side, under the assumption that the coupling coefficient of the concentric coils remains close to its design value during operation. As a result, the control system relies solely on measurements at the primary side, eliminating the need for communication between the primary and secondary sides of the system. The proposed method is based on estimating secondary-side parameters while assuming that the coupling coefficient of the concentric coils remains close to its design value during operation. The methodology begins with the mathematical modeling of the primary and secondary resonant circuits. By measuring the input voltage and current, the system estimates the load impedance, which is then used to derive the expected output voltage and a reference for the input voltage. To maintain a stable output, the system dynamically adjusts the input voltage, ensuring that it aligns with the theoretical reference value. Analytical calculations and simulations were performed using the MATLAB®/Simulink® platform to validate the proposed approach. Simulations confirmed the theoretical predictions for a wireless system operating at 120 kHz with a power transfer of 100 W. The results demonstrated that the load voltage remains stable at 32 V, even under varying load conditions, while the output current remains at 3 A despite fluctuations in battery voltage.