Wind Plant Modeling and Interconnection
System Integration researchers at NREL are engaged in wind plant modeling and interconnection analysis as explained below.
NREL Supplies WAPA with Wind Farm Training Simulator
The Western Area Power Administration (WAPA) provides electric power system operations training to power system operators and dispatchers throughout the United States and Canada at its Electric Power Training Center in Golden, Colorado. A significant portion of this training is performed with the Miniature Power System (MPS), an actual power system consisting of three synchronous generators (scaled up to 500 MW total), five loads, two ties to the western electrical grid, and a simulation of more than 500 miles of transmission lines. To enable WAPA to integrate wind energy into its training program, NREL's National Wind Technology Center supplied WAPA with a wind farm simulator in 2006 that successfully simulated power delivery to the MPS grid from a time-series file of real wind-farm data for a 50-MW wind farm.
The program is working with the wind industry to provide utilities and grid operation organizations that evaluate interconnection and system impacts of proposed wind farms with better wind generator electrical output models. Without better wind generator models, the grid evaluations will use generic induction generator parameters. By using non-wind-specific models, these evaluations will not capture the advantages of variable-speed power electronics, including their ability to provide VARs (i.e., volt-amperes reactive) and their fault ride-through capability. Without these better models, the amounts of wind capacity that will be allowed access to transmission interconnection because of concerns about system impact will be unnecessarily low.
The problem at the moment for wind developers is that existing practice for interconnection requires the same level of interconnection studies for a 25-MW wind plant as for a 1000-MW coal-steam plant, and as each study is completed the dynamics of the network often change, rendering any earlier study invalid. This is an expensive, time-consuming hurdle for most wind projects. NREL's Systems Integration staff seeks to provide the technical information required and to provide assistance where needed.
