含暂态能量裕度约束多故障最优潮流计算

Optimal Power Flow Calculation With Transient Energy Margin Constraints Under Multi-contingency Conditions

借助暂态能量裕度对发电机有功和无功出力的解析灵敏度,将暂态能量裕度约束直接加入最优潮流模型中,建立含暂态能量裕度约束多故障最优潮流逐次线性规划模型,采用单纯形法求解,取得了较好的效果。此外,还提出了根据大步长单故障最优潮流近似计算获得的暂态能量裕度进行故障扫描方法,并寻找到同一失稳模式下影响系统稳定的关键故障,验证了满足关键故障稳定性要求的最优潮流解可以同时满足同失稳模式下的其它故障的稳定约束。新英格兰10机39节点系统的最优潮流及暂态稳定计算验证了所提方法的有效性。所有优化结果均用一个在电力系统中广泛使用的暂态稳定仿真程序进行了验证。

Based on analytical sensitivity between transient energy margin and the active and reactive power of generators, constraints of transient energy margin are directly incorporated into optimal power flow （OPF） model, and hence a successive linear programming model of optimal power flow problem with transient energy margin constraints under multi-contingency conditions is formulated. The simplex algorithm is applied to solving the proposed model and some satisfying results are obtained. Furthermore, this paper proposes a method for screening contingencies by the transient energy margin obtained from approximate OPF calculation in large step length, and finds its key contingency which affects system stability largely for a certain unstable mode. Also, it is shown that the optimal power solution which satisfies stability constraints of the key contingency can also satisfy that of others which belong to the same unstable mode. Results on New England 10-machine and 39-bus system validate the proposed algorithm. Moreover, based on a widely used transient stability program, the optimization results obtained are verified.