考虑N-1故障的安全约束机组组合模型及约束削减方法

考虑N-1故障的安全约束机组组合问题规模庞大,对其进行数值求解十分困难.为此,基于直流潮流和线路开断分布因子,建立混合整数线性规划模型并提出约束削减方法.约束削减方法包括两步:根据并联支路潮流之间的关系选出需要监视的支路,以减少并联支路的安全约束;推导故障态潮流的上界,将其与故障态支路容量进行比较,以消除冗余的故障态安全约束.该约束削减方法可以在不改变最优解的前提下,大幅缩减安全约束机组组合问题的规模以及求解时间.IEEE 30和IEEE 118节点测试系统的仿真分析结果验证了所提模型及约束削减方法的有效性.

Model and constraint-reduction method for security-constrained unit commitment considering N-1 contingency

The scale of SCUC(Security-Constrained Unit Commitment) problem considering N-1 contingency is huge, and its numerical solution is very difficult, for which, a mixed-integer linear programming model is built and a constraint-reduction method is proposed. The constraint-reduction method includes two steps: the branches needed to be monitored are selected according to the relationship of power flow between parallel branches, so that the security constraints of parallel branches are reduced; the upper bound of post-contingency power flow is deduced and compared with the branch capacity of post-contingency to remove redundant post-contingency security constraints. The constraint-reduction method can greatly reduce the scale and solution time of SCUC problem without changing the optimal solution. The simulative and analysis results of IEEE 30-and 118-bus test systems verify the effectiveness of the proposed model and constraint-reduction method.