计及N-1安全准则的智能配电网多目标重构策略

智能配电网背景下,N-1安全准则是配电网安全运行中的重要准则,而现有文献中的配电网重构模型均未计及N-1安全准则,所得重构结果未必满足安全性要求。为解决这一基础性问题,文中提出了一种计及N-1安全准则的配电网多目标重构新策略。首先,基于配电系统安全域(DSSR)中安全距离这一概念,定义了安全距离均值、安全距离均衡度、安全距离均衡比3个量化描述N-1安全的指标。其次,给出了以降低网损和减小安全距离均衡比为综合优化目标的配电网多目标重构模型。然后,应用改进遗传和动态小生境差分进化的混合算法对该配电网多目标重构模型进行求解。最后,考虑静态重构和动态重构两种情境,通过算例对比所提模型与现有文献模型,结果均表明,文中模型所得重构结果满足N-1安全准则,综合考虑系统经济性、安全性下更优,验证了所提模型和求解算法的正确有效性。

A Multi-objective Reconfiguration Strategy for Smart Distribution Network Considering N-1 Security Criterion

The N-1 security criterion is a key principle for distribution operation in the background of smart distribution network. However, no N-1 criterion is taken into account in any existing distribution network reconfiguration model. The results obtained may not necessarily satisfy the security requirements. In order to solve this fundamental problem, a new multi-objective reconfiguration strategy for distribution network considering the N-1 security criterion is proposed. Firstly, three indices-average value, equilibrium degree and equilibrium ratio are defined to describe N-1 security based on the concept of security distance in the distribution system security region (DSSR). Secondly, the multi-objective reconfiguration model for distribution network is given with the aim of minimizing net loss and equilibrium ratio of security distance. Thirdly, the model is solved by the improved genetic algorithm and dynamic niche differential evolution algorithm. Finally, considering static reconfiguration and dynamic reconfiguration, the model proposed is compared with the existing model. The results show that the reconfiguration strategy can satisfy the N-1 security criterion and is better than existing models when considering economics and security of power systems, which prove the correctness and effectiveness of the model and solving method proposed. This work is supported by National High Technology Research and Development Program of China (863 Program) (No. 2014AA051901) and National Natural Science Foundation of China (No. 51477112).