Analysis of a ZVDS Class-DE current-driven full- bridge rectifier to compensation network capacitance design for WPT system

Abstract

The accurate, systematic, and effective design method of compensation network capacitance based on the series-series resonant topology is presented for reducing the reactive power of the wireless power transfer system. The design procedure uses a principle of a current-driven Class-DE full-bridge zero-voltage and zero-derivative-switching rectifier, a Class-D full-bridge zero-voltage-switching inverter, and a tightly coupled transformer. The key parameters of the Class-DE current-driven full-bridge zero-voltage and zero-derivative-switching rectifier as a function of diode conduction duty ratio are derived from the time-domain analysis with Fourier series, such as the normalized input resistance, the normalized input reactance, and the relationship of the input current and output voltage. Moreover, the advantages of the Class-DE current-driven full-bridge rectifier are that the diodes turn ON with zero-voltage-switching at low dυ/dt, turn OFF with zero-current switching and zero-voltage and zero-derivative switching at low di/dt. As a result, the switching losses and the switching noise considerably reduced. The simulation and experimental results were in good agreement with those predicted theoretically, and the maximum transfer power and the system efficiency at a transfer distance of 50 mm are 1.8 kW and 93.38 %, respectively. Therefore, the rectifier is especially suitable for high-frequency and high-efficiency resonant DC/DC converters in wireless power transfer applications.