Network power-flow analysis for a high penetration of distributed generation

Summary form only given. The connection of large numbers of small or micro-generators to low voltage distribution networks may put at risk traditional network designs. Such designs are based on traditional assumptions such as historical diversity factors and other simplifying assumptions that may no longer be appropriate. This paper describes on-going research, based on a detailed examination of a typical low voltage distribution system with increasing penetrations of distributed generation, mostly in the form of micro-generators (micro-clip, building integrated wind, and building integrated photovoltaics) connected at domestic properties. Modelling techniques have been developed that are applicable to complete distribution feeders: from primary substations, through medium and low-voltage networks to individual single-phase customer connection points. The modelling uses accurate unbalanced power-flow analysis (load-flow) and 1-minute time-series load data. Provisional results show that statistically, in terms of voltage quality and line limits, higher than expected penetrations of distributed generation can be accommodated without modifications to the distribution system. System evolution is discussed with even higher penetrations in mind