计及不确定性的输配电网协调恢复全并行分布式优化方法

Fully Parallel Distributed Optimization Method for Coordinated Recovery of Transmission and Distribution Networks Considering Uncertainty

极端事件频发导致大停电,在此期间协调优化输、配电网的恢复进程,对于提高恢复速度、减少恢复成本至关重要。然而,输、配电网分属于不同运营商,之间交互信息有限。为了在负荷恢复阶段实现二者协调运行,该文提出计及不确定性的输配电网协调恢复全并行分布式优化方法。以恢复成本最小为目标函数构建输配电网恢复运行模型,考虑风电不确定性引入模糊理论和可信性理论将确定性约束转化为模糊机会约束,并采用目标级联分析法将全局输配电网恢复问题分解为输电网恢复与配电网恢复两类子问题进行协调优化。在此基础上,引入对角二次近似对耦合变量一致性约束的惩罚函数松弛处理,从而全并行求解各子问题,提高每次迭代的计算效率。以IEEE 30节点输电网和IEEE 33节点配电网构成的输配系统为例,验证了所提方法的有效性、收敛性以及计算效率。

The frequent occurrence of the extreme events has led to major outages in recent years.It is critical that the restoration process of the transmission and distribution networks should be coordinated and optimized at this time to improve the restoration speed and reduce the costs.However,the transmission and distribution networks belong to different operators between which the information exchange is limited.In order to the achieve coordinated operation of these two networks during the load recovery phase,a fully parallel distributed optimization method is proposed.A transmission and distribution network restoration operation model is established to minimize the restoration costs,introducing the fuzzy theory and the credibility theory to transform the deterministic constraints into the fuzzy chance constraints considering the uncertainties.The analytical target cascading method is used to realize the decomposition and coordination optimization of the transmission and distribution network restoration subproblems.On this basis,a diagonal quadratic approximation is applied to relax the penalty function of the consistency constraint of the coupling variables,solving the subproblems in a fully parallel manner and improving the computational efficiency of each iteration.The effectiveness,convergence,and computational efficiency of the proposed method are verified using a transmission and distribution system consisting in an IEEE 30-bus transmission grid and an IEEE 33-bus distribution grid as an example.