Modeling and stability analysis for two paralleled UPS with no control interconnection

This paper presents a small-signal model for two single-phase paralleled UPS with no control interconnection. Basing on the proposed model, it is easy for the designer to select the slope of droop characteristics to meet the demand for stability and performance. The simulation in MATLAB confirms the validity of the small-signal model, and experiments are presented to verify the model with two single-phase 3 kVA UPS modules employed TMS320F240.