Abstract: Power Electronic Transformer (PET) consists of cascaded H-bridge (CHB) converters and dual active bridge (DAB) converters. However, the fluctuation of load causes large voltage fluctuation of high voltage DC (HVDC) and low voltage DC (LVDC) buses of PET. To address this problem, a load current feedforward control strategy for cascaded systems is proposed, which consists of two parts: the load current feedforward of DAB stage and CHB stage. The former obtains the compensated phase shift ratio of the DAB stage through calculation of the load current at the low voltage side, while the latter feeds forward the load current to the CHB stage with consideration of the power conservation of the cascade system. Moreover, considering the delay of the inner current loop of the CHB stage, the first order differential is introduced to the feedforward strategy in CHB stage, which further suppresses the voltage fluctuation on HVDC buses. The proposed control strategy only needs to sample the load current of LVDC bus, which saves the system cost greatly. In addition, the proposed strategy is easy to operate and implement. Simulation and Starsim experimental results verify the correctness and effectiveness of the proposed control method.