Stability Analysis of Partial Power Systems Based on Impedance Remodeling

In a battery energy storage system based on partial power conversion, the battery series end and the bus end are coupled to each other. After fully considering this effect, this paper performs impedance modeling for this topology. Aiming at the system instability under the battery discharge condition, an impedance remodeling control strategy is proposed by equivalent transformation of the system control block diagram. This method adjusts the intersection range between the output impedance of the source converter and the input impedance of the load converter in a small frequency range to meet the stabilization requirement of matching the system impedance. Finally, the effectiveness and practicability of the proposed battery energy storage converter scheme and control method are verified by completing the system simulation and building an experimental platform.