An Improved High-Frequency Resonant Converter With Design Considerations of Voltage-Driven Class-E Resonant Rectifier

Resonant inverter and resonant rectifier are indispensable for high-frequency resonant converters to achieve high power density, high conversion efficiency, and low electromagnetic interference. However, multiple inductors and capacitors excite complex resonances, impeding the precise parameter design through numerical computations. For the resonant rectifier, the trial method by sweeping resonant frequency and impedance parameters in simulation tools is commonly adopted, which simplifies the design procedure. Nevertheless, it relies heavily on the accuracy of simulation tools and considers only the fundamental wave. This article aims to provide a design methodology for the voltage-driven class-E resonant rectifier based on accurate calculation and comprehensive consideration. Furthermore, both harmonic factors and different connections between the inverter stage and the rectifier stage are taken into considerations. A family of improved high frequency resonant converters is presented, which enhances efficiency significantly. The operating principles analysis is expounded, and the circuit characteristics are summarized. The experimental results on the prototypes built in the laboratory demonstrate the feasibility of the theoretical analysis.