Burst Control Incorporated in Switching Period for Bidirectional Series Resonant Converter Achieving Small Voltage Ripple and Fully Soft Switching

This paper proposes a novel burst control where both ON period and OFF period are incorporated in a single switching cycle for a bidirectional series resonant converter (BSRC). The burst frequency can be increased up to a resonant frequency, hence the power pulse and the voltage ripple can be significantly reduced. The burst ON period operates at the resonant frequency to realize zero current switching ON/OFF in all switches. Such characteristic of fully soft switching is independent of the load conditions and enables minimized resonant current. The power transfer function is linear to the switching frequency and regardless of the voltage gain and the power flow direction. A 1 kVA prototype of BSRC that interfaces a high-voltage bus ranging from 240 V to 480 V and a low-voltage of 48 V is developed to validate the performance of the proposed method.