Modeling and validation of an unbalanced LV network using Smart Meter and SCADA inputs

Abstract

As new technologies such as Photovoltaics (PVs), Embedded Generators (EGs) and Electric Vehicles (EVs) penetrate Low Voltage (LV) distribution networks, the need to understand the constraints and real time system state of LV networks becomes essential for smart grid development. This paper demonstrates that, given household Smart Meter demand data combined with 66kV/22kV zone substation SCADA voltage data, it is possible to model LV networks on a per-phase basis to a high degree of accuracy in near real time. Our model is based on a real suburb in urban northern Melbourne consisting of 113 customers, and is populated with real conductor properties, route lengths and customer phase allocations to create a true unbalanced three-phase, four-wire model. Time stepped load flow simulations of the model are compared with data loggers installed on the LV network for validation, and on average simulated results differ from real measurements by less than 0.5% for phase voltages and less than 10% for phase currents. Such accuracy allows for evaluation of PV, EV and EG impact mitigation strategies and planning in reference to the Electricity Distribution Code with a strong degree of confidence. This LV model is unique as it has been validated and is the only bottom-up load model that utilizes near real time Smart Meter and SCADA inputs to analyse impacts on distribution assets on a per phase, unbalanced basis.