Unit Commitment Considering Regional Synchronous Reactive Power Requirements : Costs and Effects

Abstract

11th International Workshop on Large-scale Integration of Wind Power into Power Systems as well as on Transmission Networks for Offshore Wind Power Plants, 13-15 November, 2012, Lisbon, PortugalHighly renewable power systems may have to impose regional minima on the number of online synchronous units to ensure appropriate availability of controllable reactive power. Given the declining net loads associated with increasing wind penetration levels, these regional constraints are anticipated to come into effect with greater frequency. Such constraints have a tangible effect on the total cost of unit commitment schedules, with out-of-merit units being committed solely to preserve secure voltage regimes. The use of novel reactive power resources may make regional constraints less necessary, and the voltage-control capabilities of distribution-connected wind farms will be examined in this role. Harnessing these resources may not require any roll-out of new technology, but would be an operational change to utilise the pre-existing voltage-control capabilities implicit in the power electronic topology of modern wind turbine generators. Given the capital costs of new dedicated VAr sources, and the generating costs associated with using synchronous plant for voltage control, it appears vital to derive the greatest possible value from existing assets.Science Foundation IrelandAuthor has checked copyrightDM, 9/12/201