PCSs are used in battery energy storage systems (such as energy storage power stations and microgrids) and require collaboration with a battery management system (BMS) to implement peak load shaving and off-peak load shifting, power ancillary services, and more. The PCS is located between the battery pack and the grid, enabling bidirectional energy conversion. During discharge, it converts the battery's DC power into AC power and transmits it to the grid; during charging, it rectifies the grid's AC power into DC power for charging.

Energy Storage Inverters: Suitable for scenarios such as photovoltaic power generation, directly connected to the grid for power supply, independent of energy storage systems. They draw DC power from the battery pack, condition and control it, and then convert it into AC power for input into the grid.

Structure: PCSs are complex, consisting of a DC/AC bidirectional converter, a control unit, and communication interfaces (such as a CAN bus). Energy storage inverters have a simpler structure, primarily consisting of an inverter bridge and filter circuits.