Circulating Current in Parallel Connected Active Front End (AFE) Converters - Simulation Study

Paralleling active front end (AFE) two-level converters is a good solution when high power and redundancy are needed. The connection of multiple converters in parallel raises challenges regarding electrical energy quality and operating conditions of converters. Converters connected in parallel create paths for circulating current (CC) when converters' control systems are not synchronized. Hardware variances can also influence the converters' performance as examined in simulations. The paper contains simulation and experimental results of two 15kVA paralleled AFE converters working with different power factors.