考虑分布式电源影响的分层分区精细化切负荷方法

Hierarchical Load Shedding Method Considering Influence of Distributed Generators

直流输电故障或失去大电源时,需要快速切除部分负荷以保持受端系统稳定。传统紧急切负荷策略比较粗放,同时受端系统可能存在大量分布式电源,不恰当的切负荷控制会引起配电网过电压导致分布式电源脱网,从而引起更大停电风险。提出了一种分层分区的紧急切负荷系统架构,将待切负荷配电网划分成若干个分区。针对每个分区,通过本地测量辨识外网等值的模型参数,并建立考虑外网等值的切负荷优化模型。利用二阶锥松弛技术将该模型转化为可被有效求解的二阶锥规划模型。

When a DC transmission line or a large generator is tripped, load shedding scheme should be conducted to maintain receiving system stable. Traditional load shedding strategy is not suitable for distribution networks with high penetration of distributed generations(DGs), possibly leading to unexpected DG tripping. This paper proposes a hierarchal load shedding architecture, where the receiving system is divided into several control areas. For each control area, its external equivalent network model is identified using local measurements and incorporated into optimization model for load shedding. Furthermore, the second-order cone relaxation technique is used to transform the original non-convex model into the second-order cone programming(SOCP). This SOCP model could be solved with CPLEX efficiently. Numerical tests on integrated transmission and distribution networks validate the proposed method.