A multi-time scale tie-line energy and reserve allocation model considering wind power uncertainties for multi-area systems

Continued expansion of the power grid and the increasing proportion of wind power centralized integration leads to requirements in sharing both energy and reserves among multiple areas under a hierarchical control structure, which successively requires a correction between schedule plans within multi-time scale. In order to address this problem, this paper develops an information integration method integrating complicated relationships among fuel cost, total thermal power output, reserve capacity, owned reserves and expectations of load shedding and wind curtailment, into three types of time-related relationship curves. Furthermore, a multi-time scale tieline energy and reserves allocation model is proposed, which contains two levels in the control structure, two time scales in dispatch sequence and multiple areas integrated within wind farms as scheduling objects. The efficiency of the proposed method is tested in a 9-bus test system and IEEE 118-bus system. The results show that a cross-regional control center is able to approach the optimal scheduling results of the whole system with the integrated uploaded relationship curves. The proposed model not only relieves energy and reserve shortages in partial areas but also allocates them to more urgent need areas in a high effectivity manner in both day-ahead and intraday time scales.