Abstract: The large-scale application of energy storage can provide important support for the high proportion of renewable energy in the new power system. The high-voltage battery storage system with cascade topology distributes batteries on the DC side of each H bridge, which is an effective way to increase energy storage capacity. The control of the power conversion system can be categorized as the grid following control（GFL） and the grid forming control（GFM）. The GFL has the fast power response capability but weak grid instability risk, while the GFM has the active grid support capability but strong grid adaptability issue. This paper proposes a type-merged control method to improve the grid strength adaptability of the high-voltage large-capacity battery energy storage systems, where the flexible integration and adjustment of GFL and GFM characteristics are achieved. Simulation analysis shows the practicality and effectiveness of the proposed control method.