Abstract-Renewable energy sources such as wind and solar have received much attention in recent years, and large amount of renewable generation is being integrated to the electricity networks. A fundamental challenge in a power system operation is to handle the intermittent nature of the renewable generation. In this paper we present a stochastic programming approach to solve a multiperiod optimal power flow problem under renewable generation uncertainty. The proposed approach consists of two stages. In the first stage, operating points for the conventional power plants are determined. The second stage realizes generation from the renewable resources and optimally accommodates it by relying on the demand-side flexibilities and limited available flexibilities from the conventional generating units. The proposed model is illustrated on a 4-bus and a 39-bus system. Numerical results show that with small flexibility on the demand-side substantial benefits in terms of re-dispatch costs can be achieved. The proposed approach is tested on all standard IEEE test cases upto 300 buses for a wide variety of scenarios.Index Terms-Demand response; optimal power flow; power system modelling; linear stochastic programming; smart grids; uncertainty; wind energy.
NOMENCLATURE
Sets
BBuses, indexed by b. T Discrete set of time intervals, indexed by t .
Parameters b lSusceptance of line l .τ l Off-nominal tap ratio of line l .Min., max. real power outputs of conventional generator g .Real power demand of load d .Cost function for generator g . Cost of renewable generation spillage.Min., max. load flexibility of demand atMin., max. change in operating point ofMin., max. regulation of generator g .Downward, upward regulation cost for generator g .Cost of decreasing, increasing demand in the time period t .
P max lMax power flow capacity of line l .
Variables pReal power output of generator g .