Three-Phase Converter Models for Unbalanced Radial Power Flow Studies

This paper presents a power converter model intended for both balanced and unbalanced radial power flow studies. A three-phase steady state model of a power converter (ac/dc-dc/ac) composed of a diode rectifier, a loss-less dc link, and a pulse-width-modulated inverter is presented. Both the three-phase rectifier and the three-phase inverter are modeled as three equivalent Y-connected single-phase rectifiers and single-phase inverters, respectively. The model is implemented within a three-phase power flow solver with phase representation. Simulation results on a balanced and an unbalanced 15-bus system are presented.