考虑安全性和经济性的连锁故障预防控制策略

为阻止源头性故障引发连锁故障的安全问题,文章提出一种考虑安全性和经济性的连锁故障预防控制策略。首先,根据继电保护的动作特性给出一种判别连锁故障的数学形式。其次,以电网安全裕度和发电运行成本分别评价系统的安全性和经济性,以支路脆弱性评估方法选取初始故障,构建了针对不同初始故障作用下的连锁故障预防控制模型。该模型是一种双层优化的数学模型,内层模型采用粒子群算法求解出电网安全裕度;外层模型采用改进的多目标粒子群算法求解出最小化发电成本和最大化电网安全裕度。最后,利用模糊集理论对计算出的Pareto集合进行评估,确定最优发电机出力策略。以IEEE 39节点系统和IEEE 118节点系统为例进行仿真研究,验证了所提方法的可行性。

Preventive Control Strategy of Cascading Failure Considering Security and Economy

To prevent the security problem of cascading failures caused by source faults, this paper proposes a preventative control strategy of cascading failure considering security and the economy. Firstly, according to the action characteristics of the relay protection, a mathematical form is given to discriminate the cascading failure. Secondly, the security and economy of the system are evaluated in terms of power grid security margin and operating cost of power generation, respectively. The initial failure is selected by the branch vulnerability assessment method to construct a preventive control model of cascading failure for different initial failures actions. The model is a two-layer optimization mathematical model. The inner model is solved by the particle swarm optimization algorithm to get the power grid security margin. The outer model is solved by the improved multi-objective particle swarm optimization algorithm to minimize generation cost and maximize power grid security margin. Finally, the calculated Pareto set is evaluated using fuzzy set theory to determine the optimal output strategy of generators. Simulation studies are conducted with the IEEE 39-bus system and IEEE 118-bus system to verify the feasibility of the proposed method in this paper.