Increasing distributed generation penetration in multiphase distribution networks considering grid losses, maximum loading factor and bus voltage limits

This study proposes a new iterative algorithm to improve the performance of multiphase distribution networks by proper placement and sizing of distributed generation (DG) units and single-phase capacitors. The approach consists of utilising the positive-sequence voltage ratio V_collapse/V_no-load to identify the weakest three-phase and single-phase buses for the installation of DG units and shunt capacitors, respectively. DG penetration levels are increased by evaluating their impacts on voltage profile, grid losses and voltage stability margin while considering the voltage limits at all buses. Detailed simulations are performed for the placement and sizing of a doubly fed induction generator (DFIG) and single-phase capacitors in the IEEE multiphase 34 node test feeder using the DIgSILENT PowerFactory software. The impacts of DFIG on voltage profile, active power loss, maximum loading factor and voltage unbalance factor are highlighted.