The sub-modules of the multi-level DC-link power electronic transformer(PET) are usually composed of half bridge and double active bridge circuits. Different structures and control strategies will cause fluctuation and instability for DC-link voltage of the power electronic transformers. Traditional control strategy require a large number of current sensors, and the low-pass filter on the control link affects the dynamic response of the system. A control strategy for the multi-level DC-link power electronic transformer is proposed. The voltage sharing of DC link between power modules is realized by half-bridge circuit, and the current sharing of output current between modules is realized by DAB circuit. At the same time, the proposed control strategy only needs a current sensor at the inductance of the medium voltage DC port. All power modules do not use current sensors, which saves the cost of the system. The simulation results verify the correctness and effectiveness of the proposed control strategy.