The EEI AC/DC Transmission Model

The electric utility industry under the auspices of the Edison Electric Institute (EEI) is engaged in a research project to study the parallel operation of ac and dc transmission lines. An intermediate-power-level model, the major facet of this project, is described in this paper. The system model includes complete representation of a power system from generation to load and the system buses are interconnected by both ac and dc transmission lines. The model generation includes analog simulation of a steam turbine as well as alternator excitation and regulation. Transmission lines are represented by distributed parameters. The converter stations include 50-kW mercury-arc rectifier bridges and complete automatic controls similar to those used on actual dc transmission lines.