Modelling and analysis of practical options to improve the hosting capacity of low voltage networks for embedded photo-voltaic generation

Dwindling fossil fuel resources and concern of climate change resulting from the burning of fossil fuels have led to significant development of renewable energy in many countries. While renewable energy takes many forms, solar and wind resources are being harvested in commercial scale in many parts of the world. Government incentives such as renewable energy certificates and feed-in tariffs have contributed to the rapid uptake. In Australia many residential customers have taken up roof-top photo-voltaic (PV) systems. These residential PV generations are embedded in the low voltage (LV) networks that are not designed to take intermittent, two-way flow of electricity. Utility engineers are faced with the challenge of a legacy electricity distribution network to connect increasing amount of embedded PV generation. This study focuses on two aspects of the technical limitation - steady state voltage delivery and phase imbalance - and proposes how the technical limitations can be improved by optimising the existing voltage control schemes, the balancing of loads and generations between the supply phases, and finally the adoption of smart grid methodologies. This prioritised approach provides a cost effective means of addressing the impact of embedded PV generation. The proposed method is verified by computer simulation on a realistic LV distribution network in the state of Victoria, Australia.