Day-ahead Unit Commitment Considering of Wind Power and Bilateral Energy Contract

摘要

The operation of power system is transforming from traditional dispatching mode to market, and coupled with the uncertainty of intermittent energy, day-ahead electric power and energy balance will be a multi-objective coordination problem of new energy consumption, contract execution, grid security and generation economy in market transition phase. Studying day-ahead power balance coordination optimization model under new conditions is important to promote the consumption of wind power and ensure the fair execution of transactions. This paper used confidence interval method to model the uncertainty of wind power, established objective function and constraints to ensure the execution of contracts, and considered grid security and generation economy to establish the multi-objective coordinated unit commitment model. The paper used a test system to study the effect of confidence intervals on unit portfolio reliability and contract completion rate, to verify the validity of confidence intervals and fairness of allocation of reductions among power plants, to study the effect of power flow constraints on contract execution and the interplay among wind energy consumption, grid congestion, and contract execution. Results show that power plants reduce contracts according to their reduction factors, it will inhibit contract execution when wind power is small scale and causes a positive power flow in the blocking line, resulting in a 61.15% higher contract reduction than that without wind power; it will promote contract execution, when wind power causes reverse power flow in blocking line, leading to a 42.73% down in contract reduction compared to no wind power. It shows that the unit commitment model is effective in wind power consumption, contracts fairly execution, power grid security and the economy of power generation.