Three-Phase Grid Interface Converter Control System Design to Limit a DC-side Output Impedance

An output impedance of source converters becomes crucial for the stability of a modern power system due to presence of a large number of power converters. In the case of a hybrid power system, not only DC-DC converters but also a grid interface converter must have a limited output impedance at the DC-side. In this paper, the authors implement an output impedance limiting approach for compensators coefficient calculation of a three-phase six switch grid interface converter control system. The mathematical analysis of the converter output impedance is presented and optimal conditions of compensators coefficients for current and voltage loops are obtained. Matlab/Simulink modeling is provided to prove the correctness of the obtained results.