Improving Dynamic Response in Wireless Power Transfer Receiver Buck Converters via DC-Link Peak Voltage-Based Loop Control

In wireless power transfer (WPT) systems employing series–series or dual-sided LCC compensation, the receiver-side buck converter exhibits a current-source characteristic, resulting in a right-half-plane (RHP) zero in its power-stage small-signal model. This RHP zero imposes a fundamental tradeoff between control bandwidth and system stability, often leading to slow transient response or oscillatory behavior under conventional control schemes. To address this challenge, this article proposes a dc-link peak voltage-based loop control. Frequency-domain analysis demonstrates that the proposed method effectively decouples the dominant poles from the RHP zero, enabling the design of a higher crossover frequency to improve dynamic response. A type-III compensator is employed to shape the loop gain, achieving a 4 kHz crossover frequency with a 50◦ phase margin. Simulation and experimental results validate the effectiveness of the proposed strategy, confirming its capability to enhance dynamic performance. These findings highlight the potential of the proposed method for high-performance WPT receiver applications.