Abstract: To improve the dynamic performance, steady-state accuracy and engineering applicability of current control for a cascaded H-bridge battery energy storage converter during grid-connected charging and discharging operation, a fixed-switching-frequency two-step model predictive current control method considering digital control delay is proposed. A discrete grid-side current model is first established in the synchronous rotating reference frame, and a two-step prediction mechanism is introduced to compensate for the digital control delay. A cost function with current tracking errors and control voltage increments as optimisation objectives is then designed, and an analytical expression of the optimal control voltage is derived. The proposed method avoids the exhaustive search of switching states required in finite-control-set model predictive control and enables real-time control with low computational burden. A four-cell cascaded H-bridge battery energy storage converter experimental platform is built, and comparative tests with conventional proportional-integral control are carried out under charging/discharging current steps, mild grid-voltage unbalance disturbances and parameter deviation conditions. Experimental results show that the proposed method improves the dynamic response of the current loop while maintaining steady-state current quality, and retains good control accuracy and robustness under mild grid-voltage unbalance and parameter deviations.