Improved Modulation Strategy for Single-Phase Integrated Wireless Charging System

Wireless charging systems are widely used in electric vehicles (EVs) and often employ a two-stage structure. However, this structure often leads to increased losses and necessitates the use of bulky electrolytic capacitors with limited lifespans. To address these issues, matrix converters have been introduced to wireless charging systems. Nevertheless, the use of conventional sinusoidal pulse width modulation (SPWM) in the matrix converter-based system can lead to excessive total harmonic distortion (THD). Therefore, this study focuses on improving the modulation strategy for matrix converter-based wireless charging systems. By reallocating the dwell time of active states and zero states, the system can provide a more precise synthesized current to follow the grid sinusoidal envelope, ultimately improving the THD performance. Finally, a simulation model is built to verify the theoretical analysis, and a THD of 2.57 % is achieved.