A novel partitioning strategy for distribution networks featuring many small scale generators

The modern power distribution network is constantly changing with the introduction of small scale distributed generators (DG). DG offer great opportunities such as voltage support and reduced customer costs. However, high DG penetration can give rise to network constraint breaches such as voltage and frequency limits, fault ride through capability, system security, reliability and stability. To avoid these breaches regulation of DG is essential. With the introduction of vast numbers of DG, common regulation approaches can lead to under utilisation of DG resources, requiring unnecessary high voltage (HV) grid imports and increasing line losses.

In this study we aim to design a network partitioning strategy that enables the efficient management of DG, and maximises DG output and reduces costs. We introduce a subnet partitioning strategy that maximises the utilisation of DG power by balancing it with local demand, where locality is quantified in a modified electrical distance. We also present a case study that compares three partitioning strategies under a variety of network demands. Results show that the proposed power balanced partitioning technique can provide a structure to the DG regulation that offers better efficiency of DG operation than other partitioning strategies. In addition, the adaptive nature of the partitioning can make it capable of reducing HV grid power imports, reducing line losses, and improving voltage profiles. Furthermore, such a partitioning approach can add robustness over a range of network conditions.