Secondary distribution network power-flow analysis

Existing design methods for sizing conductors in secondary distribution networks (LV networks – typically below 500V) often employ Diversity Factors and rely heavily on a wealth of experience with similar networks and similar loads. The introduction of photovoltaic (PV) systems and micro co-generation (domestic combined heat and power: DCHP) will inevitably alter power flows in these networks, but since, at present, these distributed generators are few and far between, there is little data or experience on which to predict any effects they may have when widely installed. This paper describes on-going development of thorough and detailed modelling techniques, applicable to secondary distribution networks, using 1-minute time-series data and accurate unbalanced power-flow analysis (load-flow). These modelling techniques will provide a sound basis for the consideration of micro distributed generators.