计及风电不确定性的含UPFC电力系统的两阶段最优潮流

风速具有随机性和不确定性,大规模风电场的并网会影响电力系统的稳定性,而统一潮流控制器(UPFC)具有实时潮流控制能力,有利于系统稳定。建立计及风电不确定性的含UPFC的最优潮流模型,由日内滚动调度和实时调度两阶段组成。日内滚动调度阶段不考虑风电出力预测误差,制定机组出力计划,优化运行成本;实时调度阶段根据风电出力预测误差调节UPFC参数,实时修正运行计划,并进行潮流优化,以保证系统安全可靠。以IEEE 14节点系统和某实际系统为例进行算例分析,结果表明,所提模型可以通过UPFC的参数控制有效减少风电预测误差带来的影响,从而提高系统的经济性和安全性。

Two-stage OPF considering wind-power uncertainty for power system with UPFC

The grid-connection of large-scale wind farm may impact the stability of power system because of the randomness and uncertainty of wind speed, while UPFC(Unified Power Flow Controller) can be used to stabilize the system due to its real-time capability of power-flow control. With the consideration of wind-power uncertainty, an OPF(Optimal Power Flow) model with UPFC is built, which consists of the intraday rolling scheduling stage and the real-time scheduling stage. Without the consideration of wind-power prediction error, the intraday rolling scheduling plans the unit outputs to optimize the operational cost. The real-time scheduling regulates the UPFC parameters according to the wind-power prediction error, modifies the operational plan in real time and carries out the power-flow optimization to ensure the safety and reliability of system. The results of case analysis for IEEE 14-bus system and a practical system show that, the proposed model can effectively reduce the impact of wind-power prediction error by controlling the UPFC parameters to enhance the economy and safety of system.