Reduction of distribution feeders for simplified PV impact studies

With increasing connections of distributed rooftop PV to the distribution system, a method for simplifying the complex system to an equivalent representation of the feeder is useful to streamline the interconnection impact studies. This paper presents a method of reducing feeders to specified buses of interest while retaining equivalent electrical characteristics of the system. These buses of interest can be potential interconnection locations or buses where distribution engineers want to evaluate circuit performance. A methodology is presented showing equivalence of the reduction method with supporting equations and examples. Validation is performed for snapshot and time-series simulations with variable load and solar energy to demonstrate equivalent performance of the reduced circuit with the interconnection of PV.