Modified EPS Control with Magnetizing Current Injection to Achieve Full Load Range ZVS for Dual Active Bridge Converters

摘要

A modified extended-phase-shift (EPS) control is proposed to decrease the control complexity and achieve full load range zero-voltage-switching (ZVS) for dual-active-bridge dc-dc converters. In the proposed solution, a fixed duty cycle is added, and the magnetizing current is utilized to achieve full load range ZVS. In addition, two control variables are decoupled, because the control of duty cycle is only determined by the voltage conversion ratio, which is not affected by the phase shift angle. The ZVS models considering junction capacitors and magnetizing inductance, ZVS regions under full load range, and derivation of control law are analyzed in detail. Finally, the effectiveness of the proposed solution is verified by experimental results from a 500W, 250kHz GaN-Based prototype.