暂态稳定约束下极限传输能力的计算

Total Transfer Capability with Transient Stability Constraints

提出了计算暂态稳定性约束下极限输电能力(TTC)的模型和方法。该TTC模型把求解过 程分解为暂态稳定最优控制和最优潮流意义上的TTC两个子问题。暂态稳定最优控制把故障暂 态稳定功角约束转变为其相关机组的有功输出不等式约束。交替求解上述两个子问题,可最终求 得暂态稳定性约束下的TTC值。该方法的特点可用成熟的静态TTC方法计算暂态稳定性约束 下的TTC。同时提出了"故障分层"和"有效故障"的概念。所提出的TTC方法仅对"有效故障"进 行,有效地减轻了计算负担,提高了计算速度。在典型的10机新英格兰系统上的计算结果表明了 该算法的有效性和合理性。

New model and approach for calculating total transfer capability (TTC) with transient stability constraints is proposed. The TTC problem is divided into two sub-problems, the optimal control and the steady TTC evaluation by using conventional optimal power flow approach. By solving the optimal control sub-problem, constraints of angle stability for harmful contingencies are converted into inequality-constraints of power outputs of the correlative machines for the same harmful contingencies, and then the inequality-constraints are used in the steady TTC evaluation. Two optimal sub-problems are alternately solved in iteration for the TTC solution. The paper also proposes the concepts of hierarchical contingencies and effective contingency. By using the effective contingencies, computation burden in TTC evaluation can be significantly reduced. Simulation results on the 10-generator New England test system are given to validate efficiency and effectiveness of the TTC approach.