A novel dual active bridge(DAB)DC-DC converter based on LCL resonant network is analyzed. According to the basic characteristics of LCL resonant network

AC side voltage and current in primary and secondary full-bridges have the same phase under the dual phase shift(DSP)control

and unit power factor is achieved. Thus the backflow power generally existing in the DAB converter can be eliminated. Based on a time-domain waveform analysis

AC equivalent model of each harmonic has been developed

and the transmission power ratio of each harmonic relative to fundamental active power is calculated. The power transmission characteristics of the converter are further investigated through fundamental harmonic approximation. Finally

a 3. 6 kW experimental prototype has been designed

and waveform characteristics and backflow power experiment data are in good agreement with the theoretical analysis. Experimental results also verify its excellent properties over a wide load voltage and power range. This work is supported by Science and Technology Program of Beijing City(No. Z141100004014019).