Stability analysis for S3R-architecture Power Conditioning Units interconnection system using impedance-based methods

Abstract

Power Conditioning Unit (PCU) interconnection system solves the problem of insufficient power supply capacity of a single PCU. However, due to the complexity of the system control strategy, it is necessary to analyze the stability of the system. Based on the impedance-based method, this paper first establishes the small-signal model of the grid-connected controller (GCC) and then uses the impedance-based method to obtain the transfer function of the PCU subsystem. The stability of the PCU interconnected system composed of three PCUs is analyzed under specific working conditions. Finally, simulation and experiments verify the correctness of the analysis.

Keywords

• PCU interconnection system
• Grid-connected controller (GCC)
• Stability analysis
• Impedance-based method