Abstract: By analyzing the operational modes of the three-level converter, A bidirectional three-level DC-DC converter is designed for high-power energy storage applications.The proposed converter employs an ON/OFF hybrid control technique to address the efficiency degradation issue at high switching frequencies under light-load conditions.the resonance parameters and timing logic under steady-state conditions are derived.Based on the derived zero voltage switching（ZVS） principle is proposed to enhance performance during light-load conditions.Finally, the proposed DNPC-DAB converter is modeled and tested in Simulink and LTspice.The simulation results validate the effectiveness of soft switching in the bidirectional operating mode of the converter.The experimental findings demonstrate that the designed DNPC-DAB converter can reliably achieve ZVS under a 20% rated power load condition, thereby ensuring efficient energy conversion in energy storage units.