DIRECTLY-CONNECTED HIGH-VOLTAGE BATTERY ENERGY STORAGE SYSTEM (BESS) AND CONTROL METHOD THEREOF

A directly-connected high-voltage battery energy storage system (BESS) and a control method thereof are provided. The directly-connected high-voltage BESS includes a battery module, a direct current (DC)/DC converter, a DC bus capacitor, a DC/alternating current (AC) converter, and a grid-side filter inductor. A plurality of battery modules is connected in series to form a battery cluster. The battery cluster is connected in series to the DC/DC converter to form a battery branch, and a plurality of battery branches is connected in parallel to form a battery stack. The battery stack is connected in parallel to the DC bus capacitor and then connected to a DC port of the DC/AC converter to form a battery energy storage submodule. AC ports of a plurality of battery energy storage submodules are connected in series to form a chain-type phase converter.