Integrated Control with Energy Optimization Management of Frequency and Load Tracking for Wireless Power Transfer Systems
Revista Técnica de la Facultad de Ingeniería Universidad del Zulia
Wireless power transfer (WPT) systems are desired to provide constant output voltage with the highest possible efficiency as power supplies. In order to solve the problem of reducing the transmission efficiency caused by the dynamic change of the load condition, the coupling coefficient, the inductance coil, the compensation capacitor and the frequency offset, a method for frequency and load tracking control for WPT systems was presented in this paper. The efficiency of WPT system is analyzed
... ystem is analyzed through the equivalent model of transmitter and receiver circuit, the optimized value of the load impedance matching under the maximum efficiency of the system was obtained. The efficiency expression was deduced when the coil detuned by normalized inductance change, then we reveal that the inductance of transmitter coil was one of the main influencing factors of system efficiency. An efficiency evaluation method is put forward to evaluate the closed-loop control schemes. Based on integrated control strategy of average current polarity and phase-shifted pulse width modulation, the frequency and load tracking can be achieved at the same time. The MATLAB/Simulink experimental results show that the resonant frequency was tracked and output voltage was maintained constant. A very high overall efficiency was achieved over wide ranges of the inductance, coupling coefficient and load resistance.