An application of four‐wire grid‐forming power inverter in unbalanced distribution network

The modelling of a three-phase four-leg four-wire grid-forming inverter in low voltage distribution system 18-bus European Cigré under unbalanced conditions an autonomous network is presented. case study has two types inverters control strategy: (i) to supply all the demand interval intentional interruption and (ii) grid-following integrate photovoltaic renewable energy resources into power systems. model suggests scheme with loops: An inner current loop proportional-integral controller outer proportional controller, both synchronous reference frame (dq0), which dq-axis are decomposed positive negative sequences. Simulation results, carried out using PSCAD software, showed effectiveness suggested strategy smooth synchronization where was able form degree lower than 2%, sinusoidal frequency within standard limits 49.5–50.5 Hz.