基于安全约束机组组合的中长期电量安全校核两阶段优化

Two-stage Optimization of Medium-and Long-term Electricity Security Check Based on Security-constrained Unit Commitment

为量化评估中长期电量计划和交易合同可能对电网运行带来的安全风险,解决电量合同执行的受限因素定位与调整难题,提出了一种基于安全约束机组组合的中长期电量安全校核两阶段优化方法。阶段1严格考虑电厂的电量约束,以断面潮流越限量最小为目标建立电量校核优化模型,获得电量约束下的最优机组组合方案;阶段2则考虑电网运行约束,建立电量安全校正优化模型,通过调整机组组合方案来消除断面越限。通过统筹电力电量平衡和电网安全的两阶段优化调度,获得电量合同的可执行性结论,以及不可行时的原因定位和调整方案。实际系统算例分析验证了该方法的有效性和实用性。

A two-stage optimization method for medium-and long-term electricity security check based on security-constrained unit commitment(SCUC)is proposed to quantify and evaluate the security risks that the medium-and long-term electricity plan and trading contract may bring to the operation of power grid,and to solve the problems of locating and adjustment of the restrictive factors in the implementation of the electric quantity contract.In the first stage,the electricity constraints of the power plant are strictly analyzed.In order to minimize the over-limit of section power flow,the optimization model of electricity security check is established to obtain the optimal plan of unit commitment scheme.In the second stage,the power grid operation constraints are considered and the optimization model of electricity correction is established to eliminate the over-limit of the section by adjusting the plan of unit commitment.By coordinating the two-stage optimal dispatch of electricity balance and power grid security,the conclusion of feasibility for electricity contract can be acquired,or the orientation of causes and adjustment schemes can be obtained when it is not feasible.The effectiveness and practicability of the method are verified by the analysis of the practical systems.