Load characterization of electric radial distribution feeders

Accurate information on the real and reactive load characteristics of an electric radial distribution feeder is required for a variety of feeder applications such as power flow analysis, voltage calculations, and system expansion planning. This paper presents a new load characterization method that uses a new voltage-current-angle-logger (VCAL) which has been developed to collect data from a typical feeder. The VCAL gathers data at a few selected nodes along the distribution feeder. The VCAL samples the voltage, current, and the phase angle between the voltage and current signals. The thirty-minute average values are stored over a period of several weeks. The average values stored in the VCAL are later retrieved and used to build load duration curves for the feeder area. Load multipliers are derived from the load duration curves for a specified loading level. These multipliers are used to scale the connected kVA loads to obtain the real power and reactive power demands at the nodes for the given area. The results of laboratory tests on the VCAL and the application of the load characterization scheme to a distribution feeder of the local utility are presented